Staff directory Daniel Ruiz Molina

Daniel Ruiz Molina

CSIC Research Professor and Group Leader
dani.ruiz(ELIMINAR)@icn2.cat
Nanostructured Functional Materials

ORCID: 0000-0002-6844-8421

Publications

2024

Bioinspired phenol-based coatings for medical fabrics against antimicrobial resistance
Jose Bolaños-Cardet; Daniel Ruiz‐Molina; Vı́ctor J. Yuste; Salvio Suárez–García Chemical Engineering Journal; 481: 148674 - 148674. 2024. 10.1016/j.cej.2024.148674. IF: 13.300
Melanin-inspired conductive thin films for multimodal-sensing wearable on-skin electronics
Contreras-Pereda, Noemi; Suarez-Garcia, Salvio; Pfattner, Raphael; Ruiz-Molina, Daniel Materials Today Chemistry; 35: 101855. 2024. 10.1016/j.mtchem.2023.101855. IF: 6.700
Multidimensional Data Encoding Based on Multicolor Microencapsulated Thermoresponsive Fluorescent Phase Change Materials
Otaegui, Jaume Ramon; Ruiz-Molina, Daniel; Hernando, Jordi; Roscini, Claudio Advanced Functional Materials; 2024. 10.1002/adfm.202402510. IF: 18.500
Self-Degradable Photoactive Micromotors for Inactivation of Resistant Bacteria
Yuan, Xiaojiao; Suarez-Garcia, Salvio; De Corato, Marco; Munoz, Andres Camilo; Pagonabarraga, Ignacio; Ruiz-Molina, Daniel; Villa, Katherine Advanced Optical Materials; 12 (16): 2303137 - -. 2024. 10.1002/adom.202303137. IF: 8.000
Wearable, battery-free, wireless multiplexed printed sensors for heat stroke prevention with mussel-inspired bio-adhesive membranes
Maroli, Gabriel; Rosati, Giulio; Suarez-Garcia, Salvio; Bedmar-Romero, Daniel; Kobrin, Robert; Gonzalez-Laredo, Alvaro; Urban, Massimo; Alvarez-Diduk, Ruslan; Ruiz-Molina, Daniel; Merkoci, Arben Biosensors & Bioelectronics; 260: 116421. 2024. 10.1016/j.bios.2024.116421. IF: 10.700

2023

A mussel-inspired coating for cost-effective and environmentally friendly CO2 capture
Suárez-García, S; Nicotera, I; Ruiz-Molina, D; Simari, C Chemical Engineering Journal; 473: 145280. 2023. 10.1016/j.cej.2023.145280. IF: 15.100
Design and synthesis of unnatural coordination glycopolymer particles (CGPs): unleashing the potential of catechol-saccharide derivatives
Bideplán-Moyano, C; Lo Fiego, MJ; Calmels, JJ; Alonso, B; Radivoy, G; Ruiz-Molina, D; Mancebo-Aracil, J; Nador, F Rsc Advances; 13 (39): 27491 - 27500. 2023. 10.1039/d3ra05316d. IF: 3.900
Multistimuli-responsive smart windows based on paraffin-polymer composites
Otaegui, JR; Ruiz-Molina, D; Hernando, J; Roscini, C Chemical Engineering Journal; 463: 142390. 2023. 10.1016/j.cej.2023.142390. IF: 15.100
Mussel-Inspired Lego Approach for Controlling the Wettability of Surfaces with Colorless Coatings
Casagualda, C; Mancebo-Aracil, J; Moreno-Villaecija, M; Lopez-Moral, A; Alibes, R; Busque, F; Ruiz-Molina, D Biomimetics (Basel); 8 (1): 3. 2023. 10.3390/biomimetics8010003. IF: 4.500
Platinum-Based Nanoformulations for Glioblastoma Treatment: The Resurgence of Platinum Drugs?
Alfonso-Triguero, P; Lorenzo, J; Candiota, AP; Arus, C; Ruiz-Molina, D; Novio, F Nanomaterials; 13 (10): 1619. 2023. 10.3390/nano13101619. IF: 5.300
Roadmap on nanomedicine for the central nervous system
Ciofani, G; Campisi, M; Mattu, C; Kamm, RD; Chiono, V; Raynold, AAM; Freitas, JS; Riva, ER; Micera, S; Pucci, C; Novio, F; Lorenzo, J; Ruiz-Molina, D; Sierri, G; Re, F; Wunderlich, H; Kumari, P; Kozielski, KL; Chami, M; Marino, A; Ferreira, L Journal Of Physics-Materials; 6 (2): 22501. 2023. 10.1088/2515-7639/acab88. IF: 4.800
Water-Stable Upconverting Coordination Polymer Nanoparticles for Transparent Films and Anticounterfeiting Patterns with Air-Stable Upconversion
Zhang, JD; Ruiz-Molina, D; Novio, F; Roscini, C Acs Applied Materials & Interfaces; 15 (6): 8377 - 8386. 2023. 10.1021/acsami.2c16354. IF: 9.500

2022

Advances in Preclinical/Clinical Glioblastoma Treatment: Can Nanoparticles Be of Help?
Ruiz-Molina, D; Mao, XM; Alfonso-Triguero, P; Lorenzo, J; Bruna, J; Yuste, VJ; Candiota, AP; Novio, F Cancers; 14 (19) 2022. 10.3390/cancers14194960. IF: 6.575
Conductive properties of triphenylene MOFs and COFs
Contreras-Pereda N., Pané S., Puigmartí-Luis J., Ruiz-Molina D. Coordination Chemistry Reviews; 460 (214459) 2022. 10.1016/j.ccr.2022.214459. IF: 22.315

Triphenylene (TP) based materials have experienced a great expansion in the latest years. TP molecules have interesting optoelectronic properties, arising from the aromatic core, which have been exploited in functional two-dimensional (2D) Metal-Organic Frameworks (MOFs) and Covalent Organic Frameworks (COFs) aside other organic polymers. In this review we summarize synthetic approaches of TP-based 2D MOFs and COFs emphasizing on the resulting morphology, crystalline domains and orientation, proven to have great impact on the properties and performance of these materials in functional devices. Specifically, we report a detailed description on the different TP-based 2D structures detailing the influence of the chemical and crystalline structure on the electronic properties, specially the in-plane and out-of-plane contribution to the electrical conductivity. Finally, we give also attention and present several examples of functional devices made out with these electronic materials with great impact in the literature as well as in future technological applications. © 2022 The Authors

View abstract
Influence of modified nano-copper oxide particles on the reaction between nitrocobalamin and ascorbic acid
Polaczek, J; Stochel, G; Molina, DR; Vazquez, FN; van Eldik, R Polyhedron; 223 2022. 10.1016/j.poly.2022.115942. IF: 2.975
Intranasal Administration of Catechol-Based Pt(IV) Coordination Polymer Nanoparticles for Glioblastoma Therapy
Mao X., Calero-Pérez P., Montpeyó D., Bruna J., Yuste V.J., Candiota A.P., Lorenzo J., Novio F., Ruiz-Molina D. Nanomaterials; 12 (7, 1221) 2022. 10.3390/nano12071221. IF: 5.076

Cisplatin has been described as a potent anticancer agent for decades. However, in the case of glioblastomas, it is only considered a rescue treatment applied after the failure of second-line treatments. Herein, based on the versatility offered by coordination chemistry, we engineered nanoparticles by reaction of a platinum (IV) prodrug and iron metal ions showing in vitro dual pH-and redox-sensitivity, controlled release and comparable cytotoxicity to cisplatin against HeLa and GL261 cells. In vivo intranasal administration in orthotopic preclinical GL261 glioblastoma tumor-bearing mice demonstrated increased accumulation of platinum in tumors, leading in some cases to complete cure and prolonged survival of the tested cohort. This was corroborated by a magnetic resonance imaging follow-up, thus opening new opportunities for intranasal glioblastoma therapies while minimizing side effects. The findings derived from this research showed the potentiality of this approach as a novel therapy for glioblastoma treatment. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

View abstract
Multimodal Fluorescence Switching Materials: One Dye to Have Them All
Otaegui J.R., Carrascull-Marín A., Ruiz-Molina D., Hernando J., Roscini C. Advanced Optical Materials; 2022. 10.1002/adom.202200083.

Off/on, on/off, and on1/on2 fluorescence switching systems find application in a variety of areas, for each of which a particular dye or dye-switch tether must be specifically designed and synthesized. Herein it is demonstrated that such tight requirement can be avoided by using easily prepared mixtures of readily available emitters and phase change materials (PCMs). By proper selection of the PCM and, if needed, additives, thermo- and photothermoresponsive materials showing all classes of emission switching modes can be prepared from a single dye and without chemical modifications. This strategy can be generalized to distinct emitters and, thanks to the facile and versatile printability of dye–PCM mixtures, it can be used for the fabrication of fluorescent patterns showing complex (photo)thermal responses with direct applicability in sensing and anti-counterfeiting. © 2022 The Authors. Advanced Optical Materials published by Wiley-VCH GmbH.

View abstract
Synthesis and Validation of a Bioinspired Catechol-Functionalized Pt(IV) Prodrug for Preclinical Intranasal Glioblastoma Treatment
Mao X., Wu S., Calero-Pérez P., Candiota A.P., Alfonso P., Bruna J., Yuste V.J., Lorenzo J., Novio F., Ruiz-Molina D. Cancers; 14 (2, 410) 2022. 10.3390/cancers14020410. IF: 6.639

Glioblastoma is the most malignant and frequently occurring type of brain tumors in adults. Its treatment has been greatly hampered by the difficulty to achieve effective therapeutic concentration in the tumor sites due to its location and the blood–brain barrier. Intranasal administration has emerged as an alternative for drug delivery into the brain though mucopenetration, and rapid mucociliary clearance still remains an issue to be solved before its implementation. To address these issues, based on the intriguing properties of proteins secreted by mussels, polyphenol and catechol functionalization has already been used to promote mucopenetration, intranasal delivery and transport across the blood–brain barrier. Thus, herein we report the synthesis and study of complex 1, a Pt(IV) prodrug functionalized with catecholic moieties. This complex considerably augmented solubility in contrast to cisplatin and showed a comparable cytotoxic effect on cisplatin in HeLa, 1Br3G and GL261 cells. Furthermore, preclinical in vivo therapy using the intranasal administration route suggested that it can reach the brain and inhibit the growth of orthotopic GL261 glioblastoma. These results open new opportunities for catechol-bearing anticancer prodrugs in the treatment for brain tumors via intranasal administration. © 2022 by the authors. Licensee MDPI, Basel, Switzerland.

View abstract
Tunable Thermofluorochromic Sensors Based on Conjugated Polymers
Bellacanzone C., Otaegui J.R., Hernando J., Ruiz-Molina D., Roscini C. Advanced Optical Materials; 10 (10, 2102423) 2022. 10.1002/adom.202102423. IF: 9.926

Even though thermofluorochromic materials are eternal candidates for their use in multiple applications, they are still limited as they require complex synthetic strategies to accomplish tunable optical properties and/or provide optical changes only over a very wide temperature range. By taking advantage of the high sensitivity of the optical properties of conjugated polymers and oligomers to the external environment, herein phase change material (PCM)-based thermofluorochromic mixtures are created, where the solid-to-liquid transition of the PCM host triggers a sharp fluorescence color change of the dispersed polymers/oligomers. Fluorophore conjugation length, concentration, and PCM nature can be used to vary the spectral properties of the resulting materials along the visible region, covering a large part of the CIE 1931 color space. For the preparation of functional devices, this behavior can be directly transferred to the solid state by soaking or printing cellulose papers with the obtained thermofluorochromic mixtures as well as by structuring them into solid lipid particles that can be dispersed within polymer matrices. The resulting materials show very promising features as thermal sensors and anticounterfeiting labels. © 2022 The Authors. Advanced Optical Materials published by Wiley-VCH GmbH.

View abstract
Water-Stable Carborane-Based Eu3+/Tb3+Metal-Organic Frameworks for Tunable Time-Dependent Emission Color and Their Application in Anticounterfeiting Bar-Coding
Li Z., Núñez R., Light M.E., Ruiz E., Teixidor F., Viñas C., Ruiz-Molina D., Roscini C., Planas J.G. Chemistry of Materials; 2022. 10.1021/acs.chemmater.2c00323.

Luminescent lanthanide metal-organic frameworks (Ln-MOFs) have been shown to exhibit relevant optical properties of interest for practical applications, though their implementation still remains a challenge. To be suitable for practical applications, Ln-MOFs must be not only water stable but also printable, easy to prepare, and produced in high yields. Herein, we design and synthesize a series of mCB-EuyTb1-y (y = 0-1) MOFs using a highly hydrophobic ligand mCBL1: 1,7-di(4-carboxyphenyl)-1,7-dicarba-closo-dodecaborane. The new materials are stable in water and at high temperature. Tunable emission from green to red, energy transfer (ET) from Tb3+ to Eu3+, and time-dependent emission of the series of mixed-metal mCB-EuyTb1-y MOFs are reported. An outstanding increase in the quantum yield (QY) of 239% of mCB-Eu (20.5%) in the mixed mCB-Eu0.1Tb0.9 (69.2%) is achieved, along with an increased and tunable lifetime luminescence (from about 0.5 to 10 000 μs), all of these promoted by a highly effective ET process. The observed time-dependent emission (and color), in addition to the high QY, provides a simple method for designing high-security anticounterfeiting materials. We report a convenient method to prepare mixed-metal Eu/Tb coordination polymers (CPs) that are printable from water inks for potential applications, among which anticounterfeiting and bar-coding have been selected as a proof-of-concept. © 2022 The Authors. Published by American Chemical Society.

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2021

Antitumour activity of coordination polymer nanoparticles
Suárez-García S., Solórzano R., Alibés R., Busqué F., Novio F., Ruiz-Molina D. Coordination Chemistry Reviews; 441 (213977) 2021. 10.1016/j.ccr.2021.213977. IF: 22.315

Nanoscale coordination polymers (NCPs) have fascinated researchers over the last years. Their intrinsic theranostic properties of metal ions and organic ligands, the encapsulation of several drugs/biomolecules with excellent yields and the surface functionalisation, enhancing their biocompatibility and targeting, have remarkably impacted in prospective drug delivery alternatives in medicine. Moreover, the properties and characteristics of these nanoparticles (NPs) can be fine-tuned thanks to the synthetic flexibility of coordination chemistry. For all these reasons, the number of examples published has grown exponentially over the last years, embracing different disciplines such as molecular electronics, sensors or nanomedicine, among others. Specifically, significant advances in antitumoural applications are reported, one of the areas where this novel family of NPs has experienced a considerable advance. NCPs have accomplished a high sophistication degree and efficiency as theranostic nanoplatforms (i.e., drug delivery carriers and bioimaging probes) with long residence time in the bloodstream, targeting capacities and remarkable cellular internalisation. In this review, an introduction emphasizing the advantages of NPs for cancer treatment is included. Later on, the most representative examples of NCPs for antitumoural applications are described grouped into six mean representative areas: i) encapsulation approaches, ii) stimuli-responsive NCPs, iii) metal chemotherapy, iv) photodynamic therapy (PDT), v) unconventional therapeutic approaches and vi) theranostics. Particular emphasis is given to understand the encapsulation/release properties of these particles at the nanoscale and their interaction with biological environments, highlighting any limitation and challenges that these systems are facing from a clinical translation perspective and envisioning possible future trends and areas that will deserve further attention for the following years. © 2021 The Authors

View abstract
Bioinspired theranostic coordination polymer nanoparticles for intranasal dopamine replacement in parkinson's disease
García-Pardo J., Novio F., Nador F., Cavaliere I., Suárez-García S., Lope-Piedrafita S., Candiota A.P., Romero-Gimenez J., Rodríguez-Galván B., Bové J., Vila M., Lorenzo J., Ruiz-Molina D. ACS Nano; 15 (5): 8592 - 8609. 2021. 10.1021/acsnano.1c00453. IF: 15.881

Dopamine (DA) is one of the main neurotransmitters found in the central nervous system and has a vital role in the function of dopaminergic (DArgic) neurons. A progressive loss of this specific subset of cells is one of the hallmarks of age-related neurodegenerative disorders such as Parkinson's disease (PD). Symptomatic therapy for PD has been centered in the precursor l-DOPA administration, an amino acid precursor of DA that crosses the blood-brain barrier (BBB) while DA does not, although this approach presents medium- to long-term side effects. To overcome this limitation, DA-nanoencapsulation therapies are actively being searched as an alternative for DA replacement. However, overcoming the low yield of encapsulation and/or poor biodistribution/bioavailability of DA is still a current challenge. Herein, we report the synthesis of a family of neuromelanin bioinspired polymeric nanoparticles. Our system is based on the encapsulation of DA within nanoparticles through its reversible coordination complexation to iron metal nodes polymerized with a bis-imidazol ligand. Our methodology, in addition to being simple and inexpensive, results in DA loading efficiencies of up to 60%. In vitro, DA nanoscale coordination polymers (DA-NCPs) exhibited lower toxicity, degradation kinetics, and enhanced uptake by BE(2)-M17 DArgic cells compared to free DA. Direct infusion of the particles in the ventricle of rats in vivo showed a rapid distribution within the brain of healthy rats, leading to an increase in striatal DA levels. More importantly, after 4 days of nasal administrations with DA-NCPs equivalent to 200 μg of the free drug per day, the number and duration of apomorphine-induced rotations was significantly lower from that in either vehicle or DA-treated rats performed for comparison purposes. Overall, this study demonstrates the advantages of using nanostructured DA for DA-replacement therapy. © 2021 American Chemical Society.

View abstract
Coordination polymers nanoparticles for bioimaging
Suárez-García S., Solórzano R., Novio F., Alibés R., Busqué F., Ruiz-Molina D. Coordination Chemistry Reviews; 432 (213716) 2021. 10.1016/j.ccr.2020.213716. IF: 22.315

Early diagnosis of patient diseases is subjected to the appropriate use of bioimaging techniques. For this reason, the development of contrast agents that improve and enhance the response of current clinical imaging practices is a pressing concern. Non-invasive bioimaging techniques most often need specific probes to follow and measure biological routes in living systems. These molecular imaging agents must exhibit: I) a remarkable contrast effect, i.e. a high signal-to-noise ratio under real physiological conditions, II) pronounced in vivo stability under the effect of numerous enzymes or proteases present in serum or targeted tissue equilibrated with a fast clearance from healthy organs and III) low cost and eco-friendly production. To overcome current drawbacks that hindrance the full development of the different bioimaging techniques, several groups are exploring nanoparticles as contrast agents. In this scenario, coordination polymer nanoparticles have emerged as a handy platform offering predesigned unique advantages thanks to their chemical flexibility, structural diversity and tailoring skills. Indeed, these systems reveal high metal cargos, low toxicity and multifunctional character by adequately selecting the combination of metal ions and ligands. Moreover, in a reminiscent way of organic polymeric nanoparticles, coordination polymer nanoparticles have also demonstrated its ability to encapsulate therapeutic-active molecules, thus combining diagnostic and therapeutic functionalities, the so-called Theranostic nanomedicine. For all these reasons, the use of this family of nanoparticles as imaging contrast agents has attracted broad interest over the last years with numerous examples being reported. Herein, we review main accomplishments in the area grouped according to the used technology, including magnetic resonance imaging, computed tomography, optical imaging, radioimaging or photoacoustic imaging. © 2020 Elsevier B.V.

View abstract
Encapsulation and sedimentation of nanomaterials through complex coacervation
González-Monje P., Ayala García A., Ruiz-Molina D., Roscini C. Journal of Colloid and Interface Science; 589: 500 - 510. 2021. 10.1016/j.jcis.2020.12.067. IF: 8.128

Hypothesis: Nanoparticles removal from seawage water is a health and environmental challenge, due to the increasing use of these materials of excellent colloidal stability. Herein we hypothesize to reach this objective through complex coacervation, a straightforward, low-cost process, normally accomplished with non-toxic and biodegradable macromolecules. Highly dense polymer-rich colloidal droplets (the coacervates) obtained from a reversible charge-driven phase separation, entrap suspended nanomaterials, allowing their settling and potential recovery. Experiments: In this work we apply this process to highly stable aqueous colloidal dispersions of different surface charge, size, type and state (solid or liquid). We systematically investigate the effects of the biopolymers excess and the nanomaterials concentration and charge on the encapsulation and sedimentation efficiency and rate. This strategy is also applied to real laboratory water-based wastes. Findings: Long-lasting colloidal suspensions are succesfully destabilized through coacervate formation, which ensures high nanomaterials encapsulation efficiencies (~85%), payloads and highly tranparent supernatants (%T ~90%), within two hours. Lower polymer excess induces faster clearance and less sediments, while preserving effective nanomaterials removal. Preliminary experiments also validate the method for the clearance of real water residuals, making complex coacervation a promising scalable, low-cost and ecofriendly alternative to concentrate, separate or recover suspended micro/nanomaterials from aqueous sludges. © 2020 Elsevier Inc.

View abstract
Gossypol treatment restores insufficient apoptotic function of dff40/cad in human glioblastoma cells
Martínez-Escardó L., Alemany M., Sánchez-Osuna M., Sánchez-Chardi A., Roig-Martínez M., Suárez-García S., Ruiz-Molina D., Vidal N., Plans G., Majós C., Ribas J., Baltrons M.A., Bayascas J.R., Barcia C., Bruna J., Yuste V.J. Cancers; 13 (21, 5579) 2021. 10.3390/cancers13215579. IF: 6.639

Glioblastoma (GBM) is a highly aggressive brain tumor and almost all patients die because of relapses. GBM-derived cells undergo cell death without nuclear fragmentation upon treatment with different apoptotic agents. Nuclear dismantling determines the point-of-no-return in the apoptotic process. DFF40/CAD is the main endonuclease implicated in apoptotic nuclear disassembly. To be properly activated, DFF40/CAD should reside in the cytosol. However, the endonuclease is poorly expressed in the cytosol and remains cumulated in the nucleus of GBM cells. Here, by employing commercial and non-commercial patient-derived GBM cells, we demonstrate that the natural terpenoid aldehyde gossypol prompts DFF40/CAD-dependent nuclear fragmentation. A comparative analysis between gossypol-and staurosporine-treated cells evidenced that levels of neither caspase activation nor DNA damage were correlated with the ability of each compound to induce nuclear fragmentation. Deconvoluted confocal images revealed that DFF40/CAD was almost completely excluded from the nucleus early after the staurosporine challenge. However, gossypol-treated cells maintained DFF40/CAD in the nucleus for longer times, shaping a ribbon-like structure piercing the nuclear fragments and building a network of bridged masses of compacted chromatin. Therefore, GBM cells can fragment their nuclei if treated with the adequate insult, making the cell death process irreversible. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Hybrid Metal-Phenol Nanoparticles with Polydopamine-like Coating for PET/SPECT/CT Imaging
SuÃirez-GarcÃ-A S., Esposito T.V.F., Neufeld-Peters J., Bergamo M., Yang H., Saatchi K., Schaffer P., HÃfeli U.O., Ruiz-Molina D., RodrÃ-Guez-RodrÃ-Guez C., Novio F. ACS Applied Materials and Interfaces; 13 (9): 10705 - 10718. 2021. 10.1021/acsami.0c20612. IF: 9.229

The validation of metal-phenolic nanoparticles (MPNs) in preclinical imaging studies represents a growing field of interest due to their versatility in forming predesigned structures with unique properties. Before MPNs can be used in medicine, their pharmacokinetics must be optimized so that accumulation in nontargeted organs is prevented and toxicity is minimized. Here, we report the fabrication of MPNs made of a coordination polymer core that combines In(III), Cu(II), and a mixture of the imidazole 1,4-bis(imidazole-1-ylmethyl)-benzene and the catechol 3,4-dihydroxycinnamic acid ligands. Furthermore, a phenolic-based coating was used as an anchoring platform to attach poly(ethylene glycol) (PEG). The resulting MPNs, with effective hydrodynamic diameters of around 120 nm, could be further derivatized with surface-embedded molecules, such as folic acid, to facilitate in vivo targeting and multifunctionality. The prepared MPNs were evaluated for in vitro plasma stability, cytotoxicity, and cell internalization and found to be biocompatible under physiological conditions. First, biomedical evaluations were then performed by intrinsically incorporating trace amounts of the radioactive metals 111In or 64Cu during the MPN synthesis directly into their polymeric matrix. The resulting particles, which had identical physicochemical properties to their nonradioactive counterparts, were used to perform in vivo single-photon emission computed tomography (SPECT) and positron emission tomography (PET) in tumor-bearing mice. The ability to incorporate multiple metals and radiometals into MPNs illustrates the diverse range of functional nanoparticles that can be prepared with this approach and broadens the scope of these nanoconstructs as multimodal preclinical imaging agents. ©

View abstract
Photoactivable ruthenium-based coordination polymer nanoparticles for light-induced chemotherapy
Zhang J., Ramu V., Zhou X.-Q., Frias C., Ruiz-Molina D., Bonnet S., Roscini C., Novio F. Nanomaterials; 11 (11, 3089) 2021. 10.3390/nano11113089. IF: 5.076

Green light photoactive Ru-based coordination polymer nanoparticles (CPNs), with chemical formula [[Ru(biqbpy)]1.5 (bis)](PF6)3 (biqbpy = 6,6′-bis[N-(isoquinolyl)-1-amino]-2,2′-bipyridine; bis = bis(imidazol-1-yl)-hexane), were obtained through polymerization of the trans-[Ru(biqbpy) (dmso)Cl]Cl complex (Complex 1) and bis bridging ligands. The as-synthesized CPNs (50 ± 12 nm di-ameter) showed high colloidal and chemical stability in physiological solutions. The axial bis(imidazole) ligands coordinated to the ruthenium center were photosubstituted by water upon light irradiation in aqueous medium to generate the aqueous substituted and active ruthenium complexes. The UV-Vis spectral variations observed for the suspension upon irradiation corroborated the photoactivation of the CPNs, while High Performance Liquid Chromatography (HPLC) of irradiated particles in physiological media allowed for the first time precisely quantifying the amount of photoreleased complex from the polymeric material. In vitro studies with A431 and A549 cancer cell lines revealed an 11-fold increased uptake for the nanoparticles compared to the monomeric complex [Ru(biqbpy)(N-methylimidazole)2 ](PF6)2 (Complex 2). After irradiation (520 nm, 39.3 J/cm2), the CPNs yielded up to a two-fold increase in cytotoxicity compared to the same CPNs kept in the dark, indicating a selective effect by light irradiation. Meanwhile, the absence of1 O2 production from both nanostructured and monomeric prodrugs concluded that light-induced cell death is not caused by a photodynamic effect but rather by photoactivated chemotherapy. © 2021 by the authors. Licensee MDPI, Basel, Switzerland.

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Solvent-tuned ultrasonic synthesis of 2D coordination polymer nanostructures and flakes
Pepió B., Contreras-Pereda N., Suárez-García S., Hayati P., Benmansour S., Retailleau P., Morsali A., Ruiz-Molina D. Ultrasonics Sonochemistry; 72 (105425) 2021. 10.1016/j.ultsonch.2020.105425. IF: 7.491

Herein, a new 2-dimensional coordination polymer based on copper (II), {Cu2(L)(DMF)2}n, where L stands for 1,2,4,5-benzenetetracarboxylate (complex 1) is synthesized. Interestingly, we demonstrate that both solvent and sonication are relevant in the top-down fabrication of nanostructures. Water molecules are intercalated in suspended crystals of complex 1 modifying not only the coordination sphere of Cu(II) ions but also the final chemical formula and crystalline structure obtaining {[Cu(L)(H2O)3]·H2O}n (complex 2). On the other hand, ultrasound is required to induce the nanostructuration. Remarkably, different morphologies are obtained using different solvents and interconversion from one morphology to another seems to occur upon solvent exchange. Both complexes 1 and 2, as well as the corresponding nanostructures, have been fully characterized by different means such as infrared spectroscopy, x-ray diffraction and microscopy. © 2020 The Authors

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Synthesis of 2D Porous Crystalline Materials in Simulated Microgravity
Contreras-Pereda N., Rodríguez-San-Miguel D., Franco C., Sevim S., Vale J.P., Solano E., Fong W.-K., Del Giudice A., Galantini L., Pfattner R., Pané S., Mayor T.S., Ruiz-Molina D., Puigmartí-Luis J. Advanced Materials; 33 (30, 2101777) 2021. 10.1002/adma.202101777. IF: 30.849

To date, crystallization studies conducted in space laboratories, which are prohibitively costly and unsuitable to most research laboratories, have shown the valuable effects of microgravity during crystal growth and morphogenesis. Herein, an easy and highly efficient method is shown to achieve space-like experimentation conditions on Earth employing custom-made microfluidic devices to fabricate 2D porous crystalline molecular frameworks. It is confirmed that experimentation under these simulated microgravity conditions has unprecedented effects on the orientation, compactness and crack-free generation of 2D porous crystalline molecular frameworks as well as in their integration and crystal morphogenesis. It is believed that this work will provide a new “playground” to chemists, physicists, and materials scientists that desire to process unprecedented 2D functional materials and devices. © 2021 The Authors. Advanced Materials published by Wiley-VCH GmbH

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Thermoresponsive multicolor-emissive materials based on solid lipid nanoparticles
Otaegui J.R., Ruiz-Molina D., Latterini L., Hernando J., Roscini C. Materials Horizons; 8 (11): 3043 - 3054. 2021. 10.1039/d1mh01050f. IF: 13.266

Despite the recent advances in the field of thermofluorochromism, the fabrication of thermoresponsive multicolor-emissive materials in a simple, low-cost and versatile manner still remains a challenge. Herein we accomplish this goal by expanding the concept of matrix-induced thermofluorochromism, where a sudden two-state variation of dyes' emission is promoted by the solid-liquid transition of a surrounding phase change material (e.g., paraffins). We demonstrate that this behavior can be transferred to the nanoscale by the synthesis of dye-loaded solid lipid nanoparticles, different types of which can then be combined into a single platform to obtain multicolor thermofluorochromism using a single type of emitter. Because of the reduced dimensions of these particles, they can be utilized to prepare transparent nanocomposites and inkjet-printed patterns showing complex thermoresponsive luminescence signals and applications ranging from smart displays to thermal sensing and high-security anti-counterfeiting. © 2021 The Royal Society of Chemistry.

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Thiol-yne click reaction: an interesting way to derive thiol-provided catechols
Nador F., Mancebo-Aracil J., Zanotto D., Ruiz-Molina D., Radivoy G. RSC Advances; 11 (4): 2074 - 2082. 2021. 10.1039/d0ra09687c. IF: 3.361

The hydrothiolation of activated alkynes is presented as an attractive and powerful way to functionalize thiols bearing catechols. The reaction was promoted by a heterogeneous catalyst composed of copper nanoparticles supported on TiO2 (CuNPs/TiO2) in 1,2-dichloroethane (1,2-DCE) under heating at 80 °C. The catalyst could be recovered and reused in three consecutive cycles, showing a slight decrease in its catalytic activity. Thiol derivatives bearing catechol moieties, obtained through a versatile Michael addition, were reacted with different activated alkynes, such as methyl propiolate, propiolic acid, propiolamide or 2-ethynylpyridine. The reaction was shown to be regio- and stereoselective towards anti-Markovnikov Z-vinyl sulfide in most cases studied. Finally, some catechol derivatives obtained were tested as ligands in the preparation of coordination polymer nanoparticles (CNPs), by taking the advantage of their different coordination sites with metals such as iron and cobalt. © 2021 The Royal Society of Chemistry.

View abstract
Ultrasound-assisted exfoliation of a layered 2D coordination polymer with HER electrocatalytic activity
Contreras-Pereda N., Moghzi F., Baselga J., Zhong H., Janczak J., Soleimannejad J., Dong R., Ruiz-Molina D. Ultrasonics Sonochemistry; 70 (105292) 2021. 10.1016/j.ultsonch.2020.105292. IF: 7.491

Large blue rectangular crystals of the 2D layered coordination polymer 1 have been obtained. The interest for this complex is two-fold. First, complex 1 is made of 2D layers packing along the (0–11) direction favored by the presence of lattice and coordinated water molecules. And second, nanostructures that could be derived by delamination are potentially suitable for catalytic purposes. Therefore it represents an excellent example to study the role of interlayer solvent molecules on the ultrasound-assisted delamination of functionally-active 2D metal-organic frameworks in water, a field of growing interest. With this aim, ultrasound-assisted delamination of the crystals was optimized with time, leading to stable nanosheet colloidal water suspensions with very homogeneous dimensions. Alternative bottom-up synthesis of related nanocrystals under ultrasound sonication yielded similar shaped crystals with much higher size dispersions. Finally, experimental results evidence that the nanostructures have higher catalytic activities in comparison to their bulk counterparts, due to larger metallic center exposition. These outcomes confirm that the combination of liquid phase exfoliation and a suitable synthetic design of 2D coordination polymers represents a very fruitful approach for the synthesis of functional nanosheets with an enhancement of catalytic active sites, and in general, with boosted functional properties. © 2020 Elsevier B.V.

View abstract

2020

Highly transparent photochromic films with a tunable and fast solution-like response
Torres-Pierna H., Ruiz-Molina D., Roscini C. Materials Horizons; 7 (10): 2749 - 2759. 2020. 10.1039/d0mh01073a. IF: 12.319

The increasing interest towards photochromic films and their practical applications is driving researchers in the continuous design and synthesis of novel organic photochromic dyes with optimized performances in polymeric matrices. However, whereas their photochromic properties could be readily rationalized in organic liquid solutions, these could not be directly extrapolated to polymers as their performance changes unpredictably upon integration into a solid matrix. This leads to a time-consuming synthetic re-tuning of the dye chemical structure and/or the polymeric medium. To avoid this, herein we report an efficient, straightforward and universal strategy to embed commercial T-type organic photochromic dyes of different nature in a polymeric material without compromising their optimum solution absorption and isomerization kinetics. Our approach is based on trapping emulsified nanodroplets of a hydrophobic solution enclosing the dye into a hydrophilic polymeric matrix. The material is prepared through one single process using commercially available materials, without further modification of the components (the dye and the polymer matrix) nor requiring previous encapsulation steps. The films, which manifest true solution liquid-like and finely tunable photochromic behavior, are also highly transparent, recyclable, and scalable, and show enhanced fatigue resistance, making them highly suitable for different smart glass applications. © 2020 The Royal Society of Chemistry.

View abstract
Luminescent silicon-based nanocarrier for drug delivery in colorectal cancer cells
Marcelo G.A., Montpeyo D., Novio F., Ruiz-Molina D., Lorenzo J., Oliveira E. Dyes and Pigments; 181 (108393) 2020. 10.1016/j.dyepig.2020.108393. IF: 4.613

Nanocarriers sensitive to exogenous or endogenous stimuli emerged as an attractive alternative to target drug delivery, with inorganic silica mesoporous nanoparticles (MNs) playing a core role in the development of a new generation of non-toxic and tuneable nanocarriers. A sensitive nanovector (NANO1) comprising luminescent silicon quantum dots (SiQDs) and functionalized with MNs was synthesised and loaded with doxorubicin (DOX). NANO1 nanoparticles have a size of 74 ± 10 nm and DOX loading percentages of ca. 43%. As a control sample, a similar nanocarrier (NANO2), without SiQDs, was also synthesised and loaded with DOX. Release profile studies, in PBS, revealed the strong NANO1@DOX pH-dependant behaviour, with a pH 5.0 favouring the release of DOX to percentages of ca. 70%. Cytotoxicity assessments of both free and DOX-loaded nanocarriers were evaluated in human cell lines of colon, revealing both free drug and drug-loaded nanoparticles to be concentration-dependent. © 2020 Elsevier Ltd

View abstract
Pathway selection as a tool for crystal defect engineering: A case study with a functional coordination polymer
Abrishamkar A., Suárez–García S., Sevim S., Sorrenti A., Pons R., Liu S.-X., Decurtins S., Aromí G., Aguilà D., Pané S., deMello A.J., Rotaru A., Ruiz–Molina D., Puigmartí-Luis J. Applied Materials Today; 20 (100632) 2020. 10.1016/j.apmt.2020.100632. IF: 8.352

New synthetic routes capable of achieving defect engineering of functional crystals through well-controlled pathway selection will spark new breakthroughs and advances towards unprecedented and unique functional materials and devices. In nature, the interplay of chemical reactions with the diffusion of reagents in space and time is already used to favor such pathway selection and trigger the formation of materials with bespoke properties and functions, even when the material composition is preserved. Following this approach, herein we show that a controlled interplay of a coordination reaction with mass transport (i.e. the diffusion of reagents) is essential to favor the generation of charge imbalance defects (i.e. protonation defects) in a final crystal structure (thermodynamic product). We show that this synthetic pathway is achieved with the isolation of a kinetic product (i.e. a metastable state), which can be only accomplished when a controlled interplay of the reaction with mass transport is satisfied. Accounting for the relevance of controlling, tuning and understanding structure-properties correlations, we have studied the spin transition evolution of a well-defined spin-crossover complex as a model system. © 2020 Elsevier Ltd

View abstract
Shape Memory Polyurethane Microcapsules with Active Deformation
Zhang F., Zhao T., Ruiz-Molina D., Liu Y., Roscini C., Leng J., Smoukov S.K. ACS Applied Materials and Interfaces; 2020. 10.1021/acsami.0c14882. IF: 8.758

From smart self-tightening sutures and expandable stents to morphing airplane wings, shape memory structures are increasingly present in our daily life. The lack of methods for synthesizing intricate structures from them on the micron and submicron level, however, is stopping the field from developing. In particular, the methods for the synthesis of shape memory polymers (SMPs) and structures at this scale and the effect of new geometries remain unexplored. Here, we describe the synthesis of shape memory polyurethane (PU) capsules accomplished by interfacial polymerization of emulsified droplets. The emulsified droplets contain the monomers for the hard segments, while the continuous aqueous phase contains the soft segments. A trifunctional chemical cross-linker for shape memory PU synthesis was utilized to eliminate creep and improve the recovery ratios of the final capsules. We observe an anomalous dependence of the recovery ratio with the amount of programmed strain compared to previous SMPs. We develop quantitative characterization methods and theory to show that when dealing with thin-shell objects, alternative parameters to quantify recovery ratios are needed. We show that while achieving 94-99% area recovery ratios, the linear capsule recovery ratios can be as low as 70%. This quantification method allows us to convert from observed linear aspect ratios in capsules to find out unrecovered area strain and stress. The hollow structure of the capsules grants high internal volume for some applications (e.g., drug delivery), which benefit from much higher loading of active ingredients than polymeric particles. The methods we developed for capsule synthesis and programming could be easily scaled up for larger volume applications. Copyright © 2020 American Chemical Society.

View abstract
Solid Materials with Near-Infrared-Induced Fluorescence Modulation
Otaegui J.R., Rubirola P., Ruiz-Molina D., Hernando J., Roscini C. Advanced Optical Materials; 8 (21, 2001063) 2020. 10.1002/adom.202001063. IF: 8.286

Solid molecular materials modulating their luminescent properties upon irradiation are typically based on photochromic dyes. Despite these are potentially interesting for applications such as anticounterfeiting, bioimaging, optical data storage, and writable/erasable devices, key features are preventing their use in marketable products: the lack of straightforward strategies to obtain near infrared (NIR) radiation-responding photochromic dyes and the dramatic response modification these molecules suffer in solids. Herein a photochrome-free approach is reported to achieve solid materials whose luminescence modulation is induced by NIR radiation. This strategy is based on the capacity of phase change materials (PCMs) to modify the emission properties of fluorescent dyes upon photothermally induced interconversion between their solid and liquid states. The preparation of several NIR-responsive thermofluorochromic materials of high fatigue resistance and nondestructive readout is illustrated and this approach is extended to different commercially available dyes, taking advantage of distinct fluorescence modulation mechanisms, providing, thus, color tunability. The modulation response is straightforwardly tuned by simply varying the irradiation power density, the gold nanoshell concentration, and/or the PCM type. This tunability allows to accomplish NIR-activated multistate thermofluorochromic materials and fast/slow/irreversible responses in NIR-writings/drawings of good spatial resolution, which can be of interest for barcodings, anticounterfeiting technologies and (re)writable devices. © 2020 Wiley-VCH GmbH

View abstract

2019

Bioinspired Functional Catechol Derivatives through Simple Thiol Conjugate Addition
Mancebo-Aracil J., Casagualda C., Moreno-Villaécija M.Á., Nador F., García-Pardo J., Franconetti-García A., Busqué F., Alibés R., Esplandiu M.J., Ruiz-Molina D., Sedó-Vegara J. Chemistry - A European Journal; 25 (53): 12367 - 12379. 2019. 10.1002/chem.201901914. IF: 5.160

The combination of the surface-adhesive properties of catechol rings and functional moieties conveying specific properties is very appealing to materials chemistry, but the preparation of catechol derivatives often requires elaborate synthetic routes to circumvent the intrinsic reactivity of the catechol ring. In this work, functional catechols are synthesized straightforwardly by using the bioinspired reaction of several functional thiols with o-benzoquinone. With one exception, the conjugated addition of the thiol takes place regioselectively at the 3-position of the quinone, and is rationalized by DFT calculations. Overall, this synthetic methodology provides a general and straightforward access to functional and chain-extended catechol derivatives, which are later tested with regard to their hydro-/oleophobicity, colloidal stability, fluorescence, and metal-coordinating capabilities in proof-of-concept applications. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Color-Tunable White-Light-Emitting Materials Based on Liquid-Filled Capsules and Thermally Responsive Dyes
Vázquez-Mera N.A., Otaegui J.R., Sánchez R.S., Prats G., Guirado G., Ruiz-Molina D., Roscini C., Hernando J. ACS Applied Materials and Interfaces; 11 (19): 17751 - 17758. 2019. 10.1021/acsami.9b02169. IF: 8.456

Color-tunable white-light-emitting materials are currently attracting much attention because of their potential applications in artificial lighting, sensing, and imaging. However, preparation of these systems from organic emitters is often cumbersome due to the interchromophoric interactions occurring upon solvent drying in the final solid materials, which can be hardly predicted and may lead to detrimental effects. To circumvent these obstacles, we have developed a new fabrication methodology that relies on dye encapsulation within liquid-filled capsules, thus enabling direct transfer of the luminescent properties from solution to the solid state and as such, rational design of miniaturized white-light-emitting materials. By introducing a thermally responsive chromophore into the capsules, these materials are further endowed with color tunability, which does not only allow ample modulation of the emitted color but also facilitate external fine control of the system so as to ensure precise realization of white light at the desired temperature and excitation wavelength. © 2019 American Chemical Society.

View abstract
Delamination of 2D coordination polymers: The role of solvent and ultrasound
Contreras-Pereda N., Hayati P., Suárez-García S., Esrafili L., Retailleau P., Benmansour S., Novio F., Morsali A., Ruiz-Molina D. Ultrasonics Sonochemistry; 55: 186 - 195. 2019. 10.1016/j.ultsonch.2019.02.014. IF: 7.279

Two novel cadmium-based 2D coordination polymers have been synthesized and characterized. Experimental results evidence that the best delamination processes occurs when weak interactions dominate the cohesion between layers and solvent molecules are occluded within the crystalline network. In this case, the delamination of the crystals occurs spontaneously in water. On top of that, and thanks to the high stability of the resulting (flake) colloidal dispersions, we have completed a detailed study of the sonication assisted delamination impact by: I) comparison of two different sonication approaches (bath vs. tip sonication) and II) optimization of final flake morphology and yield by controlling solvent and sonication time. Our results definitely pave the way for the fabrication and implementation of 2D coordination polymers using ultrasound. © 2019 Elsevier B.V.

View abstract
Solid Materials with Tunable Reverse Photochromism
Julià-López A., Ruiz-Molina D., Hernando J., Roscini C. ACS Applied Materials and Interfaces; 11 (12): 11884 - 11892. 2019. 10.1021/acsami.8b22335. IF: 8.456

Herein, we report a novel, straightforward, and universal strategy to achieve solid materials with highly tunable reverse photochromism. This was accomplished by means of commercially available spiropyran dyes, which can produce different types of stable merocyanine states (i.e., nonprotonated and protonated forms) displaying distinct reverse photochromic properties (i.e., colors and coloration rates). To finely control the concentration ratio of these species and, as such, tailor the optical performance of the photochromes, we exploited their differential interaction with surrounding media of distinctive nature (i.e., nonvolatile protic and aprotic polar solvents). In this way, solutions displaying different photochromic responses were prepared for individual spiropyrans without requiring chemical derivatization, an approach that can be generalized to other spiro dyes with distinct acid-base properties. To transfer this behavior to the solid state, core-shell capsules of these solutions were prepared, which were then used as ink materials for the fabrication of flexible polymeric films with unprecedented tunability of their photochromic properties that can be employed as rewritable multicolored devices. © 2019 American Chemical Society.

View abstract
Sustainable synthesis of luminescent CdTe quantum dots coated with modified silica mesoporous nanoparticles: Towards new protein scavengers and smart drug delivery carriers
Oliveira E., Santos H.M., Jorge S., Rodríguez-González B., Novio F., Lorenzo J., Ruiz-Molina D., Capelo J.L., Lodeiro C. Dyes and Pigments; 161: 360 - 369. 2019. 10.1016/j.dyepig.2018.09.047. IF: 4.018

The synthesis and full characterization of a family of sustainable luminescent nanoparticles, CdTeQDs@MNs, made of quantum dots coated by modified mesoporous silica nanoparticles is reported. The presence of the luminescent QDs allows the imaging of the nanoparticles during cell internalization, as well as the visualization of selective release of doxorubicin inside the cell (via pH stimuli). The modified mesoporous silica nanoparticles lead to pore size improvement allowing better encapsulation and controlled release, of different active principles studied such as, small molecules (rhodamine B), drugs (doxorubicin), and isolated proteins such as bovine serum albumin, lysozyme, carbonic anhydrase, ovalbumin, α-lactalbumin, hemoglobin, myoglobin and cytochrome C. Finally, and as a proof-of-concept the efficacy of these novel platforms was demonstrated through the successful extraction and recognition of proteins in raw serum of osteoarthritis and prosthesis patients, without any previous protein depletion. © 2018 Elsevier Ltd

View abstract
The Chemistry behind Catechol-Based Adhesion
Saiz-Poseu J., Mancebo-Aracil J., Nador F., Busqué F., Ruiz-Molina D. Angewandte Chemie - International Edition; 58 (3): 696 - 714. 2019. 10.1002/anie.201801063. IF: 12.257

The adhesion of some marine organisms to almost any kind of surface in wet conditions has aroused increasing interest in recent decades. Numerous fundamental studies have been performed to understand the scientific basis of this behaviour, with catechols having been found to play a key role. Several novel bio-inspired adhesives and coatings with value-added performances have been developed by taking advantage of the knowledge gained from these studies. To date there has been no detailed overview focusing exclusively on the complex mode of action of these materials. The aim of this Review is to present recent investigations that elucidate the origin of the strong and versatile adsorption capacities of the catechol moiety and the effects of extrinsic factors that play important roles in the overall adhesion process, such as pH value, solvent, and the presence of metal ions. The aim is to detail the chemistry behind the astonishing properties of natural and synthetic catechol-based adhesive materials. © 2019 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Thermal Control of Intermolecular Interactions and Tuning of Fluorescent-State Energies
Massaro G., Zampini G., Ruiz-Molina D., Hernando J., Roscini C., Latterini L. Journal of Physical Chemistry C; 123 (8): 4632 - 4637. 2019. 10.1021/acs.jpcc.8b09774. IF: 4.309

The prospect of tuning the energy of emitting states through external stimuli opens the possibility of shifting the energy of emitting units on demand and controlling the bimolecular processes they are involved in. To prove this concept, the fluorescence properties of three differently 9,10-substituted anthracene (ANT) derivatives are investigated in a phase-change material (eicosane). The liquid-to-solid transition of the medium leads to an increase of the local dye concentration, a shortening of the intermolecular distances, and the establishment of excited- and ground-state interactions. As a result, a new contribution to the overall luminescence that derives from the downshifted emission (up to 0.7 eV) from excimer-like species is observed. The addition of a second dye (a Pt-porphyrin) reduces the efficiency of excited- and ground-state complexes between fluorophore units, although it does not prevent the formation of multichromophoric aggregates where interactions between Pt-porphyrin and the emissive state of ANT derivatives are observed. The emission of excimer-like species, formed upon solidification of the medium, can be exploited to further down-shift the fluorescence through energy-transfer processes to a suitable energy acceptor, such as rubrene. © 2019 American Chemical Society.

View abstract
Versatile iron-catechol-based nanoscale coordination polymers with antiretroviral ligand functionalization and their use as efficient carriers in HIV/AIDS therapy
Solórzano R., Tort O., García-Pardo J., Escribà T., Lorenzo J., Arnedo M., Ruiz-Molina D., Alibés R., Busqué F., Novio F. Biomaterials Science; 7 (1): 178 - 186. 2019. 10.1039/c8bm01221k. IF: 5.251

A novel chemical approach integrating the benefits of nanoparticles with versatility of coordination chemistry is reported herein to increase the effectiveness of well-known HIV antiretroviral drugs. The novelty of our approach is illustrated using a catechol ligand tethered to the known antiretroviral azidothymidine (AZT) as a constitutive building block of the nanoparticles. The resulting nanoscale coordination polymers (NCPs) ensure good encapsulation yields and equivalent antiretroviral activity while significantly diminishing its cytotoxicity. Moreover, this novel family of nanoparticles also offers (i) long-lasting drug release that is dissimilar inside and outside the cells depending on pH, (ii) triggered release in the presence of esterases, activating the antiviral activity in an on-off manner due to a proper chemical design of the ligand and (iii) improved colloidal stabilities and cellular uptakes (up to 50-fold increase). The presence of iron nodes also adds multifunctionality as possible contrast agents. The present study demonstrates the suitability of NCPs bearing pharmacologically active ligands as an alternative to conventional antiretroviral treatments. © The Royal Society of Chemistry.

View abstract

2018

Carbon nanotube-based nanocomposite sensor tuned with a catechol as novel electrochemical recognition platform of uranyl ion in aqueous samples
Muñoz J., Montes R., Bastos-Arrieta J., Guardingo M., Busqué F., Ruíz-Molina D., Palet C., García-Orellana J., Baeza M. Sensors and Actuators, B: Chemical; 273: 1807 - 1815. 2018. 10.1016/j.snb.2018.07.093. IF: 5.667

This article reports a novel electrochemical recognition platform based on a nanocomposite carbon paste electrode containing carbon nanotubes modified with gold nanoparticles carrying a thiolated catechol for the fast amperometric determination of uranyl ion (UO2 2+) in water. Recognition of UO2 2+ is accomplished by supramolecular chemistry due to the formation of an inclusion complex between catechol and UO2 2+. The amperometric device operates at –0.40 V vs. Ag/AgCl, where the reduction of UO2 2+ takes place on the electrode surface, covering a linear range from 0.49 to 170 μg L−1 UO2 2+ in a 0.1 M boric acid buffer solution at pH 5.3. The developed sensing system presents good response towards UO2 2+ in aqueous environmental samples, with good selectivity over other browsed cations and can be easily reset by simple polishing. This platform has demonstrated to be a potential alternative regarding to the common standard bench-top analytical techniques for the development of in-field devices for in-situ monitoring. © 2018 Elsevier B.V.

View abstract
Dual T1/ T2 Nanoscale Coordination Polymers as Novel Contrast Agents for MRI: A Preclinical Study for Brain Tumor
Suárez-García S., Arias-Ramos N., Frias C., Candiota A.P., Arús C., Lorenzo J., Ruiz-Molina D., Novio F. ACS Applied Materials and Interfaces; 10 (45): 38819 - 38832. 2018. 10.1021/acsami.8b15594. IF: 8.097

In the last years, extensive attention has been paid on designing and developing functional imaging contrast agents for providing accurate noninvasive evaluation of pathology in vivo. However, the issue of false-positives or ambiguous imaging and the lack of a robust strategy for simultaneous dual-mode imaging remain to be fully addressed. One effective strategy for improving it is to rationally design magnetic resonance imaging (MRI) contrast agents (CAs) with intrinsic T1/T2 dual-mode imaging features. In this work, the development and characterization of one-pot synthesized nanostructured coordination polymers (NCPs) which exhibit dual mode T1/T2 MRI contrast behavior is described. The resulting material comprises the combination of different paramagnetic ions (Fe3+, Gd3+, Mn2+) with selected organic ligands able to induce the polymerization process and nanostructure stabilization. Among them, the Fe-based NCPs showed the best features in terms of colloidal stability, low toxicity, and dual T1/T2 MRI contrast performance overcoming the main drawbacks of reported CAs. The dual-mode CA capability was evaluated by different means: in vitro phantoms, ex vivo and in vivo MRI, using a preclinical model of murine glioblastoma. Interestingly, the in vivo MRI of Fe-NCPs show T1 and T2 high contrast potential, allowing simultaneous recording of positive and negative contrast images in a very short period of time while being safer for the mouse. Moreover, the biodistribution assays reveals the persistence of the nanoparticles in the tumor and subsequent gradual clearance denoting their biodegradability. After a comparative study with commercial CAs, the results suggest these nanoplatforms as promising candidates for the development of dual-mode MRI CAs with clear advantages. © 2018 American Chemical Society.

View abstract
Dual-Fluorescent Nanoscale Coordination Polymers via a Mixed-Ligand Synthetic Strategy and Their Use for Multichannel Imaging
Nador F., Wnuk K., García-Pardo J., Lorenzo J., Solorzano R., Ruiz-Molina D., Novio F. ChemNanoMat; 4 (2): 183 - 193. 2018. 10.1002/cnma.201700311. IF: 3.173

Two rationally designed strategies for covalent bonding of fluorescent dyes in coordination polymer nanoparticles aiming to achieve bifunctional fluorescent nanostructures have been developed. The first strategy was based on the synthesis of the coordination polymers structured as nanoparticles by coordination of CoII ions to two different catechol ligands containing free functional chemical groups (dopamine and 3,4-dihydroxybenzaldehyde), and a bis(imidazole)-based ligand (1,4-bis(imidazole-1-ylmethyl)benzene, bix). Subsequently, different dyes, namely fluorescein isothiocyanate (FITC), 1-pyrenebutanoic acid hydrazide (PBH) or Alexa Fluor® 568 (A568), could be sequentially attached to the surface of the nanoparticles. The second strategy was focused on the prefunctionalization of catechol ligands with the corresponding dyes and, afterwards, the coordination with the metal ions in presence of bix. In vitro studies demonstrated the internalization of the bifunctional nanoparticles and the persistence of the fluorescent properties after cell uptake without dye leaching. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Off/On Fluorescent Nanoparticles for Tunable High-Temperature Threshold Sensing
Julià López A., Ruiz-Molina D., Landfester K., Bannwarth M.B., Roscini C. Advanced Functional Materials; 28 (28, 1801492) 2018. 10.1002/adfm.201801492. IF: 13.325

Herein, a versatile threshold temperature sensor based on the glass transition temperature-triggered fluorescence activation of a dye/developer duo, encapsulated in polymeric nanoparticles is reported. The emission enhancement, detectable even by unaided eye is completed within a narrow temperature range and activates at adjustable threshold temperatures up to 200 °C. Fluorescence is chosen as sensing probe due to its high detection sensitivity together with an advanced spatial and temporal resolution. The strategy is based on nanoparticles prepared from standard thermoplastic polymers, a fluorescence developer, and the commercially available Rhodamine B base dye, a well-known and widely used fluorescent molecule. By making nanoparticles of different thermoplastic polymers, fast, abrupt, and irreversible disaggregation induced fluorescence enhancement, with tunable threshold temperature depending on the nanoparticles polymer glass transition is achieved. As a proof-of-concept for the versatility of this novel family of NPs, their use for sensing the thermal history of environments and surfaces exposed to the threshold temperature is showed. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Polydopamine-like Coatings as Payload Gatekeepers for Mesoporous Silica Nanoparticles
Moreno-Villaécija M.-A., Sedó-Vegara J., Guisasola E., Baeza A., Regí M.V., Nador F., Ruiz-Molina D. ACS Applied Materials and Interfaces; 10 (9): 7661 - 7669. 2018. 10.1021/acsami.7b08584. IF: 8.097

We report the use of bis-catecholic polymers as candidates for obtaining effective, tunable gatekeeping coatings for mesoporous silica nanoparticles (MSNs) intended for drug release applications. In monomers, catechol rings act as adhesive moieties and reactive sites for polymerization, together with middle linkers which may be chosen to tune the physicochemical properties of the resulting coating. Stable and low-toxicity coatings (pNDGA and pBHZ) were prepared from two bis-catechols of different polarity (NDGA and BHZ) on MSN carriers previously loaded with rhodamine B (RhB) as a model payload, by means of a previously reported synthetic methodology and without any previous surface modification. Coating robustness and payload content were shown to depend significantly on the workup protocol. The release profiles in a model physiological PBS buffer of coated systems (RhB@MSN@pNDGA and RhB@MSN@pBHZ) showed marked differences in the "gatekeeping" behavior of each coating, which correlated qualitatively with the chemical nature of their respective linker moieties. While the uncoated system (RhB@MSN) lost its payload almost completely after 2 days, release from RhB@MSN@pNDGA was virtually negligible, likely due to the low polarity of the parent bis-catechol (NDGA). As opposed to these extremes, RhB@MSN@pBHZ presented the most promising behavior, showing an intermediate release of 50% of the payload in the same period of time. © 2017 American Chemical Society.

View abstract
Pt(IV)-based nanoscale coordination polymers: Antitumor activity, cellular uptake and interactions with nuclear DNA
Adarsh N.N., Frias C., Ponnoth Lohidakshan T.M., Lorenzo J., Novio F., Garcia-Pardo J., Ruiz-Molina D. Chemical Engineering Journal; 340: 94 - 102. 2018. 10.1016/j.cej.2018.01.058. IF: 6.735

Cisplatin has been for many years the gold standard chemotherapeutic drug for the treatment of a wide range of solid tumors, even though its use is commonly associated with serious side effects including non-selective toxicity, myelosuppression or development of cisplatin resistance, among others complications. Over the last decade, a number of nanoparticle formulations were developed to reduce its side effects and improve the selectivity and efficacy of this drug. In this study, we have developed a novel nanoparticle platform based on nanoscale coordination polymer named (Zn-Pt(IV)-NCPs) which contains a Pt(IV) prodrug, Zn and the linker ligand 1,4-Bis(imidazol-1-ylmethyl)benzene (bix). The main objective has been to gain insights into the mechanism of action of this nanostructured material in comparison with cisplatin and the free Pt(IV) prodrug in order to establish a correlation between nanostructuration and therapeutic activity. Zn-Pt(IV)-NCPs nanoparticles displayed an average size close to 200 nm as determined by DLS, a good stability in physiologic environments, and a controlled drug release of Pt. In vitro studies demonstrated that Pt(IV)-NCPs showed an enhanced cytotoxic effect against cell culture of cervical cancer, neuroblastoma and human adenocarcinoma cells in comparison with free Pt(IV) prodrug. Although no difference in cell uptake of Pt was observed for any of the three cell lines assayed, a higher amount of Pt bound to the DNA was found in the cells treated with the nanostructured Pt(IV) prodrug. These studies suggest that the nanostructuration of the prodrug facilitate its activation and induce a change in the mechanism of action related to an increased interaction with the DNA as corroborated by the studies of direct interaction of the Pt(IV) prodrug, nanostructured or not, with DNA. © 2018 Elsevier B.V.

View abstract
Solvent-Tuned Supramolecular Assembly of Fluorescent Catechol/Pyrene Amphiphilic Molecules
Nador F., Wnuk K., Roscini C., Solorzano R., Faraudo J., Ruiz-Molina D., Novio F. Chemistry - A European Journal; 24 (55): 14724 - 14732. 2018. 10.1002/chem.201802249. IF: 5.160

The synthesis and structuration of a novel low-molecular-weight amphiphilic catechol compound is reported. The combination of a hydrophilic tail containing a catechol unit and a pyrene-based hydrophobic head favors solvent-tuned supramolecular assembly. Formation of hollow nanocapsules/vesicles occurs in concentrated solutions of polar protic and nonprotic organic solvents, whereas a fibril-like aggregation process is favored in water, even at low concentrations. The emission properties of the pyrene moiety allow monitoring of the self-assembly process, which could be confirmed by optical and electronic microscopy. In organic solvents and at low concentrations, this compound remains in its nonassembled monomeric form. As the concentration increases, the aggregation containing preassociated pyrene moieties becomes more evident up to a critical micellar concentration, at which vesicle-like structures are formed. In contrast, nanosized twist beltlike fibers are observed in water, even at low concentrations, whereas microplate structures appear at high concentrations. The interactions between molecules in different solvents were studied by using molecular dynamics simulations, which have confirmed different solvent-driven supramolecular interactions. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Sonochemical synthesis of a novel nanoscale 1D lead(II) [Pb2(L)2(I)4]n coordination Polymer, survey of temperature, reaction time parameters
Hayati P., Suárez-García S., Gutiérrez A., Molina D.R., Morsali A., Rezvani A.R. Ultrasonics Sonochemistry; 42: 320 - 326. 2018. 10.1016/j.ultsonch.2017.11.033. IF: 6.012

One new lead(II) coordination supramolecular complex (CSC) (1D), [Pb2(L)2(I)4]n, L = C4H6N2 (1-methyl imidazole), has been synthesized under different experimental conditions. Micrometric crystals (bulk) or nano-sized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complex 1 showed that Pb2+ ion is 4-coordinated. Topological analysis shows that the complex 1 is 2,3,5C2 net. Finally, the role of reaction time and temperature on the growth and final morphology of the structures obtained by sonochemical irradiation have been studied. © 2017 Elsevier B.V.

View abstract
Sonochemical Synthesis of Optically Tuneable Conjugated Polymer Nanoparticles
Bellacanzone C., Roscini C., del Carmen Ruiz Delgado M., Ponce Ortiz R., Ruiz-Molina D. Particle and Particle Systems Characterization; 35 (2, 1700322) 2018. 10.1002/ppsc.201700322. IF: 4.384

The development of novel and simple methodologies for the obtaining of semiconductive polymer nanoparticles with fine-tuned optical properties represents nowadays a challenging research area as it involves a simultaneous chemical modification and nanostructuration of the polymer. Here, starting from poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene], this objective is achieved with the one-pot synthesis of oligomers with tunable conjugation length and their nanostructuration, employing a miniemulsion method. Ultrasound irradiation of heterogeneous mixtures leads to the formation of hypochlorous acid that disrupts the electronic conjugation through polymer chain cleavage. Moreover, control over the degree of the electronic conjugation of the oligomers, and therefore of the optical properties, is achieved simply by varying the polymer concentration of the initial solution. Finally, the presence of surfactants during the sonication allows for the formation of nanoparticles with progressive spectral shift of the main absorption (from λmax = 476 to 306 nm) and emission bands (from λmax = 597 to 481 nm). The integration of conducting polymer nanoparticles into polymeric matrices yields self-standing and flexible fluorescent films. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim

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Sonochemical synthesis of two novel Pb(II) 2D metal coordination polymer complexes: New precursor for facile fabrication of lead(II) oxide/bromide micro-nanostructures
Hayati P., Suárez-García S., Gutierrez A., Şahin E., Molina D.R., Morsali A., Rezvani A.R. Ultrasonics Sonochemistry; 42: 310 - 319. 2018. 10.1016/j.ultsonch.2017.11.037. IF: 6.012

Two new lead(II) coordination polymer complexes (CSCs) (2D), [Pb2(L)2(Br)2]n·H2O (1), [Pb2(HL/)(L/)(H2O)2]n·H2O (2), where L = C6H5NO2 (2-pyridinecarboxylic acid) and L/ = C9H6O6 (1,3,5-tricarboxylic acid), have been synthesized under different experimental conditions. Micrometric crystals (bulk) or microsized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on complexes 1 and 2 shows that Pb2+ ions are 8-coordinated, 7 and 9-coordinated, respectively. Topological analysis shows that the compound 1 and 2 are 4,6L26 and bnn net, respectively. However, neither the shape nor the morphology is maintained, showing the role of sonochemistry to modulate both morphology and dimensions of the resulting crystalline material, independently of whether we have a 2D coordination polymer (CP). Finally, micro structuration of lead(II) bromide oxide and lead(II) oxide have been prepared by calcination of two different lead (II) CPs at 700 °C that were characterized by SEM and XRD. © 2017 Elsevier B.V.

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Spin-Crossover in an Exfoliated 2D Coordination Polymer and Its Implementation in Thermochromic Films
Salvio Suárez-García, Nayarassery N. Adarsh, Gábor Molnár, Azzedine Bousseksou, Yann Garcia, Marinela M. Dîrtu, Javier Saiz-Poseu, Roberto Robles, Pablo Ordejón, and Daniel Ruiz-Molina ACS Applied Nano Materials; 1 (6): 2662 - 2668. 2018. 10.1021/acsanm.8b00341 . IF: 0.000

Development of novel 2D materials with singular and thrilling properties has aroused large interest due to the novel unexpected applications that can be derived from there. In this sense, coordination polymers (CPs) have appeared as matching candidates thanks to their rational chemical design and the added-value properties given by the presence of metal ions. This is the case of switchable spin-crossover systems that have been proposed as excellent candidates for data storage or sensing, among others. Here we report the delamination of crystals of the 2D spin-crossover (SCO) {[Fe(L1)2](ClO4)2}∝ (1) CP by liquid-phase exfoliation (LPE) in water. The application of this top-down technique results in the formation of flakes with controlled thicknesses, down to 1–2 nm thick (mostly mono- and bilayer), that retain the chemical composition and SCO interconversion of the bulk material. Moreover, these flakes can be handled as stable colloidal dispersions for many days. This allows for a controlled transfer to solid substrates and the formation of thermochromic polymeric films as a proof-of-concept of device. These first results will definitely open new venues and opportunities for the investigation and future integration of these original switchable 2D materials in devices.

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Surface functionalization of metal-organic frameworks for improved moisture resistance
Castells-Gil J., Novio F., Padial N.M., Tatay S., Ruíz-Molina D., Martí-Gastaldo C. Journal of Visualized Experiments; 2018 (139, e58052) 2018. 10.3791/58052. IF: 1.184

Metal-organic frameworks (MOFs) are a class of porous inorganic materials with promising properties in gas storage and separation, catalysis and sensing. However, the main issue limiting their applicability is their poor stability in humid conditions. The common methods to overcome this problem involve the formation of strong metal-linker bonds by using highly charged metals, which is limited to a number of structures, the introduction of alkylic groups to the framework by post-synthetic modification (PSM) or chemical vapour deposition (CVD) to enhance overall hydrophobicity of the framework. These last two usually provoke a drastic reduction of the porosity of the material. These strategies do not permit to exploit the properties of the MOF already available and it is imperative to find new methods to enhance the stability of MOFs in water while keeping their properties intact. Herein, we report a novel method to enhance the water stability of MOF crystals featuring Cu2(O2C)4 paddlewheel units, such as HKUST (where HKUST stands for Hong Kong University of Science & Technology), with the catechols functionalized with alkyl and fluoro-alkyl chains. By taking advantage of the unsaturated metal sites and the catalytic catecholase-like activity of CuII ions, we are able to create robust hydrophobic coatings through the oxidation and subsequent polymerization of the catechol units on the surface of the crystals under anaerobic and water-free conditions without disrupting the underlying structure of the framework. This approach not only affords the material with improved water stability but also provides control over the function of the protective coating, which enables the development of functional coatings for the adsorption and separations of volatile organic compounds. We are confident that this approach could also be extended to other unstable MOFs featuring open metal sites. © 2018, Journal of Visualized Experiments. All rights reserved.

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2017

Bioinspired catechol-based systems: Chemistry and applications
d'Ischia M., Ruiz-Molina D. Biomimetics; 2 (4, 25) 2017. 10.3390/biomimetics2040025.

[No abstract available]

View abstract
Copolymerization of a Catechol and a Diamine as a Versatile Polydopamine-Like Platform for Surface Functionalization: The Case of a Hydrophobic Coating
Salvio Suárez-García, Josep Sedó, Javier Saiz-Poseu, Daniel Ruiz-Molina Biomimetics ; 2 (4, 22) 2017. 10.3390/biomimetics2040022.

The covalent functionalization of surfaces with molecules capable of providing new properties to the treated substrate, such as hydrophobicity or bioactivity, has been attracting a lot of interest in the last decades. For achieving this goal, the generation of a universally functionalizable primer coating in one-pot reaction and under relatively mild conditions is especially attractive due to its potential versatility and ease of application. The aim of the present work is to obtain such a functionalizable coating by a cross-linking reaction between pyrocatechol and hexamethylenediamine (HDMA) under oxidizing conditions. For demonstrating the efficacy of this approach, different substrates (glass, gold, silicon, and fabric) have been coated and later functionalized with two different alkylated species (1-hexadecanamine and stearoyl chloride). The success of their attachment has been demonstrated by evaluating the hydrophobicity conferred to the surface by contact angle measurements. Interestingly, these results, together with its chemical characterization by means of X-ray photoelectron spectroscopy (XPS) and Fourier-transform infrared spectroscopy (FT-IR), have proven that the reactivity of the primer coating towards the functionalizing agent can be tuned in function of its generation time.

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Ligand and solvent effects in the formation and self-assembly of a metallosupramolecular cage
Adarsh N.N., Chakraborty A., Tarrés M., Dey S., Novio F., Chattopadhyay B., Ribas X., Ruiz-Molina D. New Journal of Chemistry; 41 (3): 1179 - 1185. 2017. 10.1039/C6NJ03456J. IF: 3.269

Two bis-pyridyl-bis-urea ligands namely N,N′-bis-(3-pyridyl)diphenylmethylene-bis-urea (L1) and N,N′-bis-(3-picolyl)diphenylmethylene-bis-urea (L2) have been reacted with a Cu(ii) salt resulting in the formation of a metallosupramolecular cage [{Cu2(μ-L1)4(DMSO)2(H2O)2}·SO4·X] (1) and a one-dimensional coordination polymer [{Cu(1)(μ-L2)2(H2O)2}{Cu(2)(μ-L2)2(H2O)2}·2SO4·9H2O·X]n (2) (where DMSO = dimethylsulfoxide, and X = disordered lattice included solvent molecules), respectively. The single crystal structures of 1 and 2 are discussed in the context of the effect of the ligands, particularly the hydrogen bonding functionality of the ligand, on the supramolecular structural diversities observed in these metal organic compounds. The supramolecular packing of 1 is clearly influenced by the nature of the solvent and ligand used; mixtures of DMSO/MeOH or DMSO/H2O lead to the formation of blue crystals or a hydrogel, respectively. © The Royal Society of Chemistry and the Centre National de la Recherche Scientifique.

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Recent advances in porous nanoparticles for drug delivery in antitumoral applications: inorganic nanoparticles and nanoscale metal-organic frameworks
Baeza A., Ruiz-Molina D., Vallet-Regí M. Expert Opinion on Drug Delivery; 14 (6): 783 - 796. 2017. 10.1080/17425247.2016.1229298. IF: 5.657

Introduction: Nanotechnology has provided new tools for addressing unmet clinical situations, especially in the oncology field. The development of smart nanocarriers able to deliver chemotherapeutic agents specifically to the diseased cells and to release them in a controlled way has offered a paramount advantage over conventional therapy. Areas covered: Among the different types of nanoparticle that can be employed for this purpose, inorganic porous materials have received significant attention in the last decade due to their unique properties such as high loading capacity, chemical and physical robustness, low toxicity and easy and cheap production in the laboratory. This review discuss the recent advances performed in the application of porous inorganic and metal-organic materials for antitumoral therapy, paying special attention to the application of mesoporous silica, porous silicon and metal-organic nanoparticles. Expert opinion: The use of porous inorganic nanoparticles as drug carriers for cancer therapy has the potential to improve the life expectancy of the patients affected by this disease. However, much work is needed to overcome their drawbacks, which are aggravated by their hard nature, exploiting the advantages offered by highly the ordered pore network of these materials. © 2016 Informa UK Limited, trading as Taylor & Francis Group.

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Replacing nitrogen by sulfur: From structurally disordered eumelanins to regioregular thiomelanin polymers
Iacomino M., Mancebo-Aracil J., Guardingo M., Martín R., D’Errico G., Perfetti M., Manini P., Crescenzi O., Busqué F., Napolitano A., d’Ischia M., Sedó J., Ruiz-Molina D. International Journal of Molecular Sciences; 18 (10, 2169) 2017. 10.3390/ijms18102169. IF: 3.226

The oxidative polymerization of 5,6-dihydroxybenzothiophene (DHBT), the sulfur analog of the key eumelanin building block 5,6-dihydroxyindole (DHI), was investigated to probe the role of nitrogen in eumelanin build-up and properties. Unlike DHI, which gives a typical black insoluble eumelanin polymer on oxidation, DHBT is converted to a grayish amorphous solid (referred to as thiomelanin) with visible absorption and electron paramagnetic resonance properties different from those of DHI melanin. Mass spectrometry experiments revealed gradational mixtures of oligomers up to the decamer level. Quite unexpectedly, nuclear magnetic resonance (NMR) analysis of the early oligomer fractions indicated linear, 4-, and 7-linked structures in marked contrast with DHI, which gives highly complex mixtures of partially degraded oligomers. Density functional theory (DFT) calculations supported the tendency of DHBT to couple via the 4- and 7-positions. These results uncover the role of nitrogen as a major determinant of the structural diversity generated by the polymerization of DHI, and point to replacement by sulfur as a viable entry to regioregular eumelanin-type materials for potential applications for surface functionalization by dip coating. © 2017 by the authors. Licensee MDPI, Basel, Switzerland.

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Sonochemical synthesis, characterization, and effects of temperature, power ultrasound and reaction time on the morphological properties of two new nanostructured mercury(II) coordination supramolecule compounds
Hayati P., Rezvani A.R., Morsali A., Molina D.R., Geravand S., Suarez-Garcia S., Villaecija M.A.M., García-Granda S., Mendoza-Meroño R., Retailleau P. Ultrasonics Sonochemistry; 37: 382 - 393. 2017. 10.1016/j.ultsonch.2017.01.021. IF: 4.218

Two new mercury(II) coordination supramolecular compounds (CSCs) (1D and 0D), [Hg(L)(I)2]n (1) and [Hg2(L′)2(SCN)2]·2H2O (2) (L = 2-amino-4-methylpyridine and L′ = 2,6-pyridinedicarboxlic acid), have been synthesized under different experimental conditions. Micrometric crystals (bulk) or nano-sized materials have been obtained depending on using the branch tube method or sonochemical irradiation. All materials have been characterized by field emission scanning electron microscope (FESEM), scanning electron microscopy (SEM), powder X-ray diffraction (PXRD) and FT-IR spectroscopy. Single crystal X-ray analyses on compounds 1 and 2 show that Hg2+ ions are 4-coordinated and 5-coordinated, respectively. Topological analysis shows that the compound 1 and 2 have 2C1, sql net. The thermal stability of compounds 1 and 2 in bulk and nano-size has been studied by thermal gravimetric (TG), differential thermal analyses (DTA) for 1 and differential scanning calorimetry (DSC) for 2, respectively. Also, by changing counter ions were obtained various structures 1 and 2 (1D and 0D, respectively). The role of different parameters like power of ultrasound irradiation, reaction time and temperature on the growth and morphology of the nano-structures are studied. Results suggest that increasing power ultrasound irradiation and temperature together with reducing reaction time and concentration of initial reagents leads to a decrease in particle size. © 2017 The Authors

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Surface Functionalization of Metal-Organic Framework Crystals with Catechol Coatings for Enhanced Moisture Tolerance
Castells-Gil J., Novio F., Padial N.M., Tatay S., Ruíz-Molina D., Martí-Gastaldo C. ACS Applied Materials and Interfaces; 9 (51): 44641 - 44648. 2017. 10.1021/acsami.7b15564. IF: 7.504

Robust catechol coatings for enhanced moisture tolerance were produced in one step by direct reaction of Hong Kong University of Science and Technology (HKUST) with synthetic catechols. We ascribe the rapid formation of homogeneous coatings around the metal-organic framework particles to the biomimetic catalytic activity of Cu(II) dimers in the external surface of the crystals. Use of fluorinated catechols results in hydrophobic, permeable coatings that protect HKUST from water degradation while retaining close to 100% of its original sorption capacity. © 2017 American Chemical Society.

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Synthesis and Characterization of PtTe2 Multi-Crystallite Nanoparticles using Organotellurium Nanocomposites
Fernández-Lodeiro J., Rodríguez-Gónzalez B., Novio F., Fernández-Lodeiro A., Ruiz-Molina D., Capelo J.L., Santos A.A.D., Lodeiro C. Scientific Reports; 7 (1, 9889) 2017. 10.1038/s41598-017-10239-8. IF: 4.259

Herein, we report the synthesis of new PtTe2 multi-crystallite nanoparticles (NPs) in different sizes through an annealing process using new nanostructured Pt-Te organometallic NPs as a single source precursor. This precursor was obtained in a single reaction step using Ph2Te2 and H2PtCl6 and could be successfully size controlled in the nanoscale range. The resulting organometallic composite precursor could be thermally decomposed in 1,5 pentanediol to yield the new PtTe2 multi-crystallite NPs. The final size of the multi-crystallite spheres was successfully controlled by selecting the nanoprecursor size. The sizes of the PtTe2 crystallites formed using the large spheres were estimated to be in the range of 2.5-6.5 nm. The results provide information relevant to understanding specific mechanistic aspects related to the synthesis of organometallic nanomaterials and nanocrystals based on platinum and tellurium. © 2017 The Author(s).

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Synthesis of Polydopamine-Like Nanocapsules via Removal of a Sacrificial Mesoporous Silica Template with Water
Nador F., Guisasola E., Baeza A., Villaecija M.A.M., Vallet-Regí M., Ruiz-Molina D. Chemistry - A European Journal; 23 (12): 2753 - 2758. 2017. 10.1002/chem.201604631. IF: 5.317

Hollow polymeric polydopamine (PDA) micro-/nanocapsules have been obtained through a very simple, mild, and straightforward method that involves coating of silica mesoporous nanoparticles through an ammonia-triggered polymerization of PDA and the posterior removal of the sacrificial template simply by dispersion in water, without the need of any harsh chemical reagent, either in the presence or absence of active principles, from doxorubicin to iron oxide nanoparticles. To demonstrate the potential of the nanocapsules obtained with this new approach, they have been successfully used as nanocarriers for drug delivery. © 2017 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

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2016

Biocompatible polydopamine-like particles for the removal of heavy metals at extremely low concentrations
Contreras Rodríguez A.R., Saiz-Poseu J., García-Pardo J., García B., Lorenzo J., Ojea-Jiménez I., Komilis D., Sedó J., Busqué F., Sánchez A., Ruiz-Molina D., Font X. RSC Advances; 6 (46): 40058 - 40066. 2016. 10.1039/c6ra03664c. IF: 3.289

A family of catechol-based submicron particles, with sizes between 200 and 300 nm, was tested for the removal of Cd(ii), Pb(ii) and Cr(vi) in water. The highest adsorption capacity was obtained with catechol-based particles in the case of Pb(ii), followed by Cd(ii). However, the catechol particles failed to adsorb Cr(vi). Our results indicate an up to four-fold increase of the adsorption capacity of these particles compared to that of activated carbon under the same experimental conditions. To check the biocompatible character of the submicron particles, their stability was evaluated in a phosphate buffer solution (PBS) and in a cell culture medium. The results confirmed that the presence of proteins in the medium favors their stability. A bioluminescent Vibrio fischeri test and a cytotoxicity assay on the HepG2 cell line were used to determine that the catechol particles did not exhibit any substantial toxicity. The results show that these catechol-based particles can be used as an efficient biocompatible adsorbent to remove heavy metals at extremely low concentrations. © The Royal Society of Chemistry 2016.

View abstract
Coordination polymers build from 1,4-bis(imidazol-1yl-methyl)benzene: From Crystalline to Amorphous
N. N Adarsh, F. Novio, D. Ruiz-Molina Dalton Transactions; 45 (28): 11233 - 11255. 2016. 10.1039/C6DT01157H. IF: 4.177

The supramolecular chemistry of the bis-imidazole ligand 1,4-bis(imidazol-1-ylmethyl)benzene, popularly known as bix, has been explored by various researchers in order to synthesize functional coordination polymers (CPs). The flexibility of the bix ligand, its unpredictable conformation and its coordination behaviour with transition metal ions have resulted in a huge number of structurally diverse and functionally intriguing CPs. In this perspective review we discuss the progress in CPs of bix between 1997 and today. More precisely, this review emphasizes the developments in functional supramolecular coordination polymers built from the bix ligand, from crystalline materials to amorphous nanomaterials.

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Nanoscale coordination polymers obtained in ultrasmall liquid droplets on solid surfaces and its comparison to different synthetic volume scales
Bellido E., González-Monje P., Guardingo M., Novio F., Sánchez A., Montero M., Molnar G., Bousseksou A., Ruiz-Molina D. RSC Advances; 6 (80): 76666 - 76672. 2016. 10.1039/c6ra14368g. IF: 3.289

Synthesis of coordination polymers at femtolitre scales assisted by an AFM tip has become an area of increasing interest due to the astonishing range of implications that derive from it, from gaining basic knowledge of confined reactions in femtolitre droplets to the fabrication of molecular-based devices. However, this field is still in its infancy, a reason why several new basic studies that allow us control over it are highly required. Herein we report the synthesis of [Co(CH3COO)2(μ-4,4′-bpy)] in femtolitre droplets on surfaces and the results are compared with those obtained for the same reaction at different volume scales. ©2016 The Royal Society of Chemistry.

View abstract
Reactions in ultra-small droplets by tip-assisted chemistry
Guardingo M., Busqué F., Ruiz-Molina D. Chemical Communications; 52 (78): 11617 - 11626. 2016. 10.1039/c6cc03504c. IF: 6.567

The confinement of chemical reactions within small droplets has received much attention in the last few years. This approach has been proved successful for the in-depth study of naturally occurring chemical processes as well as for the synthesis of different sets of nanomaterials with control over their size, shape and properties. Different approaches such as the use of self-contained structures or microfluidic generated droplets have been followed over the years with success. However, novel approaches have emerged during the last years based on the deposition of femtolitre-sized droplets on surfaces using tip-assisted lithographic methods. In this feature article, we review the advances made towards the use of these ultra-small droplets patterned on surfaces as confined nano-reactors. © 2016 The Royal Society of Chemistry.

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Switchable colloids, thin-films and interphases based on metal complexes with non-innocent ligands: The case of valence tautomerism and their applications
Vázquez-Mera N.A., Novio F., Roscini C., Bellacanzone C., Guardingo M., Hernando J., Ruiz-Molina D. Journal of Materials Chemistry C; 4 (25): 5879 - 5889. 2016. 10.1039/c6tc00038j. IF: 5.066

Successful nanostructuration approaches developed in the last few years have allowed the preparation of robust valence tautomeric (VT) switchable (micro-/nano-) structures of a variety of dimensions and morphologies. These results are expected to definitely foster the implementation of these materials on hybrid molecular electronic devices but also endorse new applications in other different fields such as sensing, drug delivery or water remediation, among others. © The Royal Society of Chemistry 2016.

View abstract
Synthesis of Nanoscale Coordination Polymers in Femtoliter Reactors on Surfaces
Guardingo M., González-Monje P., Novio F., Bellido E., Busqué F., Molnár G., Bousseksou A., Ruiz-Molina D. ACS Nano; 10 (3): 3206 - 3213. 2016. 10.1021/acsnano.5b05071. IF: 13.334

In the present work, AFM-assisted lithography was used to perform the synthesis of a coordination polymer inside femtoliter droplets deposited on surfaces. For this, solutions of the metal salt and the organic ligand were independently transferred to adjacent tips of the same AFM probe array and were sequentially delivered on the same position of the surface, creating femtoliter-sized reaction vessels where the coordination reaction and particle growth occurred. Alternatively, the two reagents were mixed in the cantilever array by loading an excess of the inks, and transferred to the surface immediately after, before the precipitation of the coordination polymer took place. The in situ synthesis allowed the reproducible obtaining of round-shaped coordination polymer nanostructures with control over their XY positioning on the surface, as characterized by microscopy and spectroscopy techniques. © 2016 American Chemical Society.

View abstract
Temperature-Controlled Switchable Photochromism in Solid Materials
Julià-López A., Hernando J., Ruiz-Molina D., González-Monje P., Sedó J., Roscini C. Angewandte Chemie - International Edition; 55 (48): 15044 - 15048. 2016. 10.1002/anie.201608408. IF: 11.709

A novel strategy to achieve thermally switchable photochromism in solid materials is reported, which relies on the preparation of polymeric core–shell capsules containing solutions of photochromic dyes in acidic phase-change materials. Upon changing the phase (solid or liquid) of the encapsulated medium, one of the two photochromic states of the system is selectively stabilized on demand, allowing for reversible interconversion between direct and reverse photochromism when thermally scanning through the melting temperature of the phase-change material. This strategy, which does not require the addition of external agents or chemical modification of the dyes, proved to be general for different spiropyran photochromes and to be applicable to the fabrication of a variety of functional materials by simply embedding the capsules obtained into a solid matrix of choice. © 2016 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim

View abstract
Thermally Switchable Molecular Upconversion Emission
Massaro G., Hernando J., Ruiz-Molina D., Roscini C., Latterini L. Chemistry of Materials; 28 (3): 738 - 745. 2016. 10.1021/acs.chemmater.5b03532. IF: 9.407

In this work a novel strategy is introduced to achieve thermally switchable emission from photon upconversion (UC) systems based on organic dyes. When these molecules were dissolved at low concentrations in phase-change media, a reversible, sharp, and nearly complete interconversion from blue upconverted emission to red luminescence was observed around the solid-to-liquid transition of the system. This result was rationalized in terms of dye aggregation, which selectively occurs in the solid state and dramatically enhances the inter-chromophoric energy transfer processes leading to UC. Notably, this behavior is extendable to different media and dyes, which allows an easy tuning of the switching temperature and emission colors. In addition, with proper selection of the phase-change medium, our strategy permits facile preparation of solid molecular materials showing photon UC at room temperature and even at sub-micromolar dye concentrations. © 2016 American Chemical Society.

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2015

Covalent Grafting of Coordination Polymers on Surfaces: The Case of Hybrid Valence Tautomeric Interphases
González-Monje P., Novio F., Ruiz-Molina D. Chemistry - A European Journal; 21 (28): 10094 - 10099. 2015. 10.1002/chem.201500671. IF: 5.731

We have developed a novel approach for grafting coordination polymers, structured as nanoparticles bearing surface reactive carboxylic groups, to amino-functionalized surfaces through a simple carbodiimide-mediated coupling reaction. As a proof-of-concept to validate our approach, and on the quest for novel hybrid interphases with potential technological applications, we have used valence tautomeric nanoparticles exhibiting spin transition at or around room temperature. SEM and AFM characterization reveal that the nanoparticles were organized chiefly into a single monolayer while X-ray photoelectron spectroscopy (XPS) measurements confirm that the nanoparticles retain a temperature-induced electronic redistribution upon surface anchorage. Our results represent an effective approach towards the challenging manufacture of coordination polymers. CPPs immobilization: A generic approach for immobilizing coordination polymer nanoparticles (CPPs) on gold surfaces is reported. The protocol involves covalent bonding between amino-terminated alkyl chains on the gold surface and carboxylic groups on the CPPs surface. The thickness of the nanoparticle monolayer is comparable to the nanoparticle size. The nanoparticles used exhibit valence tautomerism in bulk and keep this property after surface attachment, as corroborated by X-ray photoelectron spectroscopy (XPS) measurements. The results represent an effective approach towards the manufacture of coordination polymers. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

View abstract
Design and Synthesis of a Noninnocent Multitopic Catechol and Pyridine Mixed Ligand: Nanoscale Polymers and Valence Tautomerism
Guardingo M., Busqué F., Novio F., Ruiz-Molina D. Inorganic Chemistry; 54 (14): 6776 - 6781. 2015. 10.1021/acs.inorgchem.5b00598. IF: 4.762

The design and synthesis of a new redox-active ligand combining catechol and pyridine units have allowed the achievement of cobalt-based nanoscale coordination polymer particles in a single-step exhibiting a switchable valence tautomeric behavior and thermal hysteresis. The combination of polymerizing capabilities with redox-active responses in a unique ligand leads to the formation of nanoparticles exhibiting a gradual valence tautomeric interconversion in the 35-370 K temperature range. Using one single ligand to obtain these nanoparticles facilitates possible nanostructure formation methodologies. (Chemical Equation Presented). © 2015 American Chemical Society.

View abstract
Dual T1/T2 MRI contrast agent based on hybrid SPION@coordination polymer nanoparticles
Borges M., Yu S., Laromaine A., Roig A., Suárez-García S., Lorenzo J., Ruiz-Molina D., Novio F. RSC Advances; 5 (105): 86779 - 86783. 2015. 10.1039/c5ra17661a. IF: 3.840

We report a novel hybrid T1/T2 dual MRI contrast agent by the encapsulation of SPIONs (T2 contrast agent) into an iron-based coordination polymer with T1-weighted signal. This new hybrid material presents improved relaxometry and low cytotoxicity, which make it suitable for its use as contrast agent for MRI. © 2015 The Royal Society of Chemistry.

View abstract
Liquid-Filled Valence Tautomeric Microcapsules: A Solid Material with Solution-Like Behavior
Vázquez-Mera N.A., Roscini C., Hernando J., Ruiz-Molina D. Advanced Functional Materials; 25 (26): 4129 - 4134. 2015. 10.1002/adfm.201501166. IF: 11.805

The integration of stimuli-responsive valence tautomeric (VT) molecular systems into solid materials without compromising their functionality is a major bottleneck for the use of these compounds in high-added value applications. In this work, an innovative, simple, and universal approach is described to tackle this challenge based on the confinement of the active species into liquid-filled polymeric capsules. A microstructured solid with optimized solution-like behavior is obtained in this way, whose VT properties can be rationally tuned upon variation of the encapsulated solvent. Incorporation of the resulting capsules into thin films or other matrices of interest allows successful transfer of valence tautomerism from the liquid phase to solid materials, thus paving the way to the fabrication of functional devices based on spin transition compounds. © 2015 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

View abstract

2014

Amorphous Coordination Polymer Particles for Biomedicine
Novio F., Ruiz-Molina D., Lorenzo J. Bio- and Bioinspired Nanomaterials; 9783527335817: 113 - 138. 2014. 10.1002/9783527675821.ch05.

This chapter focuses on a specific class of coordination polymeric materials with different dimensionality, but with an amorphous superstructure. The terminology coordination polymer particles (CPPs) is used to designate the new emergent class of amorphous nanoparticles with highly tailorable size and properties that open up new perspectives in different fields, especially in medicine. The chapter outlines the most recent advances in the synthesis, characterization, and properties of CPPs with a high potential to be used as multifunctional platforms for theranostics, including smart drug-delivery systems, active nanostructures for bioimaging, or a combination of both. It compiles currently considerable effort to incorporate theranostics functions into a single nanoscale system for the more effective treatment of medical diseases, especially cancer. The chapter summarizes the most interesting coordination polymer nanodevices in the field of medicine, from encapsulation and drug delivery to bioimaging and sensing. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. All rights reserved.

View abstract
Bio- and Bioinspired Nanomaterials
Ruiz-Molina D., Novio F., Roscini C. Bio- and Bioinspired Nanomaterials; 9783527335817: 1 - 457. 2014. 10.1002/9783527675821.

A comprehensive overview of nanomaterials that are inspired by or targeted at biology, including some of the latest breakthrough research. Throughout, valuable contributions from top-level scientists illustrate how bionanomaterials could lead to novel devices or structures with unique properties. The first and second part cover the most relevant synthetic and bioinspired nanomaterials, including surfaces with extreme wettability properties, functional materials with improved adhesion or structural and functional systems based on the complex and hierarchical organization of natural composites. These lessons from nature are explored in the last section where bioinspired materials are proposed for biomedical applications, showing their potential for future applications in drug delivery, theragnosis, and regenerative medicine. A navigational guide aimed at advanced and specialist readers, while equally relevant for readers in research, academia or private companies focused on high added-value contributions. Young researchers will also find this an indispensable guide in choosing or continuing to work in this stimulating area, which involves a wide range of disciplines, including chemistry, physics, materials science and engineering, biology, and medicine. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. All rights reserved.

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Bioinspired catechol-terminated self-assembled monolayers with enhanced adhesion properties
Guardingo, M.; Bellido, E.; Miralles-Llumà, R.; Faraudo, J.; Sedõ, J.; Tatay, S.; Verdaguer, A.; Busqué, F.; Ruiz-Molina, D. Small; 10 (8): 1594 - 1602. 2014. 10.1002/smll.201302406. IF: 7.514
Carboxyl Group (-CO2H) functionalized coordination polymer nanoparticles as efficient platforms for drug delivery
Novio, F.; Lorenzo, J.; Nador, F.; Wnuk, K.; Ruiz-Molina, D. Chemistry - A European Journal; 20 (47): 15443 - 15450. 2014. 10.1002/chem.201403441. IF: 5.696
Catechol-Based Biomimetic Functional Materials and their Applications
Busqué F., Sedó J., Ruiz-Molina D., Saiz-Poseu J. Bio- and Bioinspired Nanomaterials; 9783527335817: 277 - 308. 2014. 10.1002/9783527675821.ch11.

In recent decades, biomaterials have inspired scientists from different fields to design and develop novel functional materials. One paradigmatic example of this fructiferous approach has been the fabrication of new bioinspired materials based on catechol structures. These aromatic derivatives bearing two ortho hydroxyl groups are ubiquitous in nature, where they display a large variety of functions. This functional versatility can be explained considering that catechols can act simultaneously as weak acids and easily oxidizable reducing agents, along with the fact that the presence of the two aromatic hydroxyl groups in vicinal positions makes them ideal for bidentate coordination and intermolecular noncovalent interactions. Intense research has been aimed at mimicking the natural roles of catechols by developing new functional materials. This chapter is centered on past, recent, and on-going studies involving the design, development, and biomimetic use of synthetic molecules and materials with catechols present in their structure, mainly in the fields of biomedicine, analytical, nanotechnology, and materials science, with special emphasis on these last two disciplines. © 2015 Wiley-VCH Verlag GmbH & Co. KGaA. All rights reserved.

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Controlling spin transition in one-dimensional coordination polymers through polymorphism
Novio, F.; Campo, J.; Ruiz-Molina, D. Inorganic Chemistry; 53 (16): 8742 - 8748. 2014. 10.1021/ic5013928. IF: 4.794
Coordination Polymer Particles with ligand-centred pH-responses and spin transition
Nador, F.; Novio, F.; Ruiz-Molina, D. Chemical Communications; 50 (93): 14570 - 14572. 2014. 10.1039/c4cc05299d. IF: 6.718
Effect of surfactants on the performance of tubular and spherical micromotors-a comparative study
Simmchen, J.; Magdanz, V.; Sanchez, S.; Chokmaviroj, S.; Ruiz-Molina, D.; Baeza, A.; Schmidt, O.G. RSC Advances; 4 (39): 20334 - 20340. 2014. 10.1039/c4ra02202e. IF: 3.708
Hydrophobic coordination polymer nanoparticles and application for oil-water separation
Novio, F.; Ruiz-Molina, D. RSC Advances; 4 (29): 15293 - 15296. 2014. 10.1039/c4ra00850b. IF: 3.708
Improving catalase-based propelled motor endurance by enzyme encapsulation
Simmchen, J.; Baeza, A.; Ruiz-Molina, D.; Vallet-Regí, M. Nanoscale; 6 (15): 8907 - 8913. 2014. 10.1039/c4nr02459a. IF: 6.739
Mussel-inspired hydrophobic coatings for water-repellent textiles and oil removal
García, B.; Saiz-Poseu, J.; Gras-Charles, R.; Hernando, J.; Alibés, R.; Novio, F.; Sedó, J.; Busqué, F.; Ruiz-Molina, D. ACS Applied Materials and Interfaces; 6 (20): 17616 - 17625. 2014. 10.1021/am503733d. IF: 5.900
Synthesis of polydopamine at the femtoliter scale and confined fabrication of Ag nanoparticles on surfaces
Guardingo, M.; Esplandiu, M.J.; Ruiz-Molina, D. Chemical Communications; 50 (83): 12548 - 12551. 2014. 10.1039/c4cc02500h. IF: 6.718

2013

Catechol-based biomimetic functional materials
Sedõ, J.; Saiz-Poseu, J.; Busqué, F.; Ruiz-Molina, D. Advanced Materials; 25: 653 - 701. 2013. 10.1002/adma.201202343. IF: 14.829
Coordination polymer nanoparticles in medicine
Novio, F.; Simmchen, J.; Vázquez-Mera, N.; Amorín-Ferré, L.; Ruiz-Molina, D. Coordination Chemistry Reviews; 257: 2839 - 2847. 2013. 10.1016/j.ccr.2013.04.022. IF: 11.016
Encapsulation and release mechanisms in coordination polymer nanoparticles
Amorín-Ferré, L.; Busqué, F.; Bourdelande, J.L.; Ruiz-Molina, D.; Hernando, J.; Novio, F. Chemistry - A European Journal; 19 (51): 17508 - 17516. 2013. 10.1002/chem.201302662. IF: 5.831
Liquid-filled capsules as fast responsive photochromic materials
Vázquez-Mera, N.; Roscini, C.; Hernando, J.; Ruiz-Molina, D. Advanced Optical Materials; 1: 631 - 636. 2013. 10.1002/adom.201300121. IF: 0.000
Mn12 single molecule magnets deposited on μ-SQUID sensors: The role of interphases and structural modifications
Bellido, E.; González-Monje, P.; Repollés, A.; Jenkins, M.; Sesé, J.; Drung, D.; Schurig, T.; Awaga, K.; Luis, F.; Ruiz-Molina, D. Nanoscale; 5 (24): 12565 - 12573. 2013. 10.1039/c3nr02359a. IF: 6.233
Robust spin crossover platforms with synchronized spin switch and polymer phase transition
Novio, F.; Evangelio, E.; Vazquez-Mera, N.; González-Monje, P.; Bellido, E.; Mendes, S.; Kehagias, N.; Ruiz-Molina, D. Scientific Reports; 3 2013. 10.1038/srep01708. IF: 2.927
Surface-confined molecular coolers for cryogenics
Lorusso, G.; Jenkins, M.; González-Monje, P.; Arauzo, A.; Sesé, J.; Ruiz-Molina, D.; Roubeau, O.; Evangelisti, M. Advanced Materials; 25: 2984 - 2988. 2013. 10.1002/adma.201204863. IF: 14.829
Versatile nanostructured materials via direct reaction of functionalized catechols
Saiz-Poseu, J.; Sedõ, J.; García, B.; Benaiges, C.; Parella, T.; Alibés, R.; Hernando, J.; Busqué, F.; Ruiz-Molina, D. Advanced Materials; 25: 2066 - 2070. 2013. 10.1002/adma.201204383. IF: 14.829

2012

Advances on structuring, integration and magnetic characterization of molecular nanomagnets on surfaces and devices
Domingo, N.; Bellido, E.; Ruiz-Molina, D. Chemical Society Reviews; 41: 258 - 302. 2012. 10.1039/c1cs15096k.
Controlled positioning of nanoparticles on graphene by noninvasive AFM lithography
Bellido, E.; Ojea-Jiménez, I.; Ghirri, A.; Alvino, C.; Candini, A.; Puntes, V.; Affronte, M.; Domingo, N.; Ruiz-Molina, D. Langmuir : the ACS journal of surfaces and colloids; 28: 12400 - 12409. 2012. 10.1021/la3023419.
Self-assembly of a catechol-based macrocycle at the liquid-solid interface: Experiments and molecular dynamics simulations
Saiz-Poseu, J.; Martínez-Otero, A.; Roussel, T.; Hui, J.K.-H.; Montero, M.L.; Urcuyo, R.; MacLachlan, M.J.; Faraudo, J.; Ruiz-Molina, D. Physical Chemistry Chemical Physics; 14: 11937 - 11943. 2012. 10.1039/c2cp41407d.
Self-assembly of alkylcatechols on HOPG investigated by scanning tunneling microscopy and molecular dynamics simulations
Saiz-Poseu, J.; Alcón, I.; Alibés, R.; Busqué, F.; Faraudo, J.; Ruiz-Molina, D. CrystEngComm; 14: 264 - 271. 2012. 10.1039/c1ce06010d.
Structuration and integration of magnetic nanoparticles on surfaces and devices
Bellido, E.; Domingo, N.; Ojea-Jiménez, I.; Ruiz-Molina, D. Small; 8: 1465 - 1491. 2012. 10.1002/smll.201101456.
Switchable self-assembly of a bioinspired alkyl catechol at a solid/liquid interface: Competitive interfacial, noncovalent, and solvent interactions
Saiz-Poseu, J.; Faraudo, J.; Figueras, A.; Alibes, R.; Busqué, F.; Ruiz-Molina, D. Chemistry - A European Journal; 18: 3056 - 3063. 2012. 10.1002/chem.201101940.

2011

Alternating current magnetic susceptibility of a molecular magnet submonolayer directly patterned onto a micro superconducting quantum interference device
Martínez-Pérez, M.J.; Bellido, E.; De Miguel, R.; Sesé, J.; Lostao, A.; Gómez-Moreno, C.; Drung, D.; Schurig, T.; Ruiz-Molina, D.; Luis, F. Applied Physics Letters; 99 2011. 10.1063/1.3609859.
Assisted-assembly of coordination materials into advanced nanoarchitectures by Dip Pen nanolithography
Bellido, E.; Cardona-Serra, S.; Coronado, E.; Ruiz-Molina, D. Chemical Communications; 47: 5175 - 5177. 2011. 10.1039/c1cc10630a.
Multiplexed arrays of chemosensors by parallel dip-pen nanolithography
Martínez-Otero, A.; González-Monje, P.; Maspoch, D.; Hernando, J.; Ruiz-Molina, D. Chemical Communications; 47: 6864 - 6866. 2011. 10.1039/c0cc03838e.
Parallel Dip-Pen Nanolithography as a tool for the fabrication of multiplexed arrays of chemosensors
Bellido, E. ; Cardona-Serra, S.; Coronado, E.; Ruiz-Molina, D. Chemical Communications; 47: 6864 - 6866. 2011. .
Ultrasensitive broad band SQUIDmicrosusceptometer for magnetic measurementsat very low temperatures
Martínez-Pérez, M. J.; Sesé, J.; Luis, F.; Córdoba, R.; Drung, D.; Schurig, Th.; Bellido, E.; de Miguel, R.; Gómez-Moreno, C.; Lostao, A.; Ruíz-Molina, D. IEEE Transactions on Applied Superconductivity; 21 (3): 345 - 348. 2011. .

2010

Coexistence of two thermally induced intramolecular electron transfer processes in a series of metal complexes [M(Cat-N-BQ)(Cat-N-SQ)]/ [M(Cat-N-BQ)2] (M = Co, Fe, and Ni) bearing non-innocent catechol-based ligands: A combined experimental and theoretical study
Evangelio, E.; Bonnet, M.-L.; Cabañas, M.; Nakano, M.; Sutter, J.P.; Dei, A.; Robert, V.; Ruiz-Molina, D. Chemistry - A European Journal; 16: 6666 - 6677. 2010. 10.1002/chem.200902568.
Controlling the number of proteins with dip-pen nanolithography
Bellido, E.; De Miguel, R.; Ruiz-Molina, D.; Lostao, A.; Maspoch, D. Advanced Materials; 22: 352 - 355. 2010. 10.1002/adma.200902372.
Coordination polymer particles as potential drug delivery systems
Imaz, I.; Rubio-Martínez, M.; García-Fernández, L.; García, F.; Ruiz-Molina, D.; Hernando, J.; Puntes, V.; Maspoch, D. Chemical Communications; 46: 4737 - 4739. 2010. 10.1039/c003084h.
Effect of crystalline disorder on quantum tunneling in the single-molecule magnet Mn12 benzoate
Carbonera, C.; Luis, F.; Campo, J.; Sánchez-Marcos, J.; Camón, A.; Chaboy, J.; Ruiz-Molina, D.; Imaz, I.; Van Slageren, J.; Dengler, S.; González, M. Physical Review B - Condensed Matter and Materials Physics; 81: 014427-1 - 014427-10. 2010. 10.1103/PhysRevB.81.014427.
Metal-radical chains based on polychlorotriphenylmethyl radicals: Synthesis, structure, and magnetic properties
Roques, N.; Domingo, N.; Maspoch, D.; Wurst, K.; Rovira, C.; Tejada, J.; Ruiz-Molina, D.; Veciana, J. Inorganic Chemistry; 49: 3482 - 3488. 2010. 10.1021/ic100037z.
Nanoscale positioning of inorganic nanoparticles using biological ferritin arrays fabricated by Dip-Pen Nanolithography
Bellido, E.; De Miguel, R.; Sesé, J.; Ruiz-Molina, D.; Lostao, A.; Maspoch, D. Scanning; 32: 35 - 41. 2010. 10.1002/sca.20162.
Structuration of pH-responsive fluorescent molecules on surfaces by soft lithographic techniques
Martínez-Otero, A.; Busqué, F.; Hernando, J.; Ruiz-Molina, D. Nanoscale; 2: 1781 - 1788. 2010. 10.1039/c0nr00169d.
Ultrasensitive Broad Band SQUID Microsusceptometer for Magnetic Measurements at Very Low Temperatures
Martinez-Perez, M. J.; Sese, J.; Luis, F.; Cordoba, R.; Drung, D.; Schurig, T.; Bellido, E.; de Miguel, R.; Gomez-Moreno, C.; Lostao, A.; Ruiz-Molina, D. IEEE Transactions on Applied Superconductivity; 2010. .

2009

Acetylcholinesterase as an amyloid enhancing factor in PrP82-146 aggregation process
Pera, M.; Martínez-Otero, A.; Colombo, L.; Salmona, M.; Ruiz-Molina, D.; Badia, A.; Clos, M.V. Molecular and Cellular Neurosciences; 40: 217 - 224. 2009. 10.1016/j.mcn.2008.10.008.
Alignment of magnetic anisotropy axes in crystals of Mn12 acetate and Mn12 -tBuAc molecular nanomagnets: Angle-dependent ac susceptibility study
Burzurí, E.; Carbonera, C.; Luis, F.; Ruiz-Molina, D.; Lampropoulos, C.; Christou, G. Physical Review B - Condensed Matter and Materials Physics; 80 2009. 10.1103/PhysRevB.80.224428.
How well aligned are the magnetic anisotropy axes in crystals of Mn12 molecular nanomagnets? An angle-dependent ac susceptibility study
E. Burzuri; Ch. Carbonera; F. Luis; D. Ruiz-Molina; C. Lampropoulos; G. Christou Physical Review B; 80: 224428. 2009. http://dx.doi.org/10.1103/PhysRevB.80.224428.
Metal-organic spheres as functional systems for guest encapsulation
Imaz, I.; Hernando, J.; Ruiz-Molina, D.; Maspoch, D. Angewandte Chemie - International Edition; 48: 2325 - 2329. 2009. .
Morphological investigation of Mn12 single-molecule magnets adsorbed on au(111)
Otero, G.; Evangelio, E.; Rosero, C.; Vázquez, L.; Gómez-Segura, J.; Gago, J.A.M.; Ruiz-Molina, D. Langmuir : the ACS journal of surfaces and colloids; 25: 10107 - 10115. 2009. 10.1021/la900710c.
Particle-size dependence of magnetization relaxation in Mn12 crystals
Domingo, N.; Luis, F.; Nakano, M.; Muntó, M.; Gómez, J.; Chaboy, J.; Ventosa, N.; Campo, J.; Veciana, J.; Ruiz-Molina, D. Physical Review B - Condensed Matter and Materials Physics; 79 2009. 10.1103/PhysRevB.79.214404.
Solvent effects on valence tautomerism: A comparison between the interconversion in solution and solid state
Evangelio, E.; Rodriguez-Blanco, C.; Coppel, Y.; Hendrickson, D.N.; Sutter, J.P.; Campo, J.; Ruiz-Molina, D. Solid State Sciences; 11: 793 - 800. 2009. 10.1016/j.solidstatesciences.2007.11.039.
Specific solvent effects on the intramolecular electron transfer reaction in a neutral ferrocene donor polychlorotriphenylmethyl acceptor radical with extended conjugation
Sporer, C.; Ratera, I.; Ruiz-Molina, D.; Gancedo, J.V.; Ventosa, N.; Wurst, K.; Jaitner, P.; Rovira, C.; Veciana, J. Solid State Sciences; 11: 786 - 792. 2009. 10.1016/j.solidstatesciences.2007.09.028.

2008

A hexacarboxylic open-shell building block: Synthesis, structure and magnetism of a three-dimensional metal-radical framework
Roques, N.; Maspoch, D.; Luis, F.; Camón, A.; Wurst, K.; Datcu, A.; Rovira, C.; Ruiz-Molina, D.; Veciana, J. Journal of Materials Chemistry; 18: 98 - 108. 2008. 10.1039/b713705b.
Catechol derivatives as fluorescent chemosensors for wide-range pH detection
Evangelio, E.; Hernando, J.; Imaz, I.; Bardají, G.G.; Alibés, R.; Busqué, F.; Ruiz-Molina, D. Chemistry - A European Journal; 14: 9754 - 9763. 2008. 10.1002/chem.200800722.
Intramolecular electron transfer in the mixed-valence [Co(3,5-DTBCat)(3,5-DTBSQ)(bpy)] complex: Beyond valence tautomerism
Evangelio, E.; Hendrickson, D.N.; Ruiz-Molina, D. Inorganica Chimica Acta; 361: 3403 - 3409. 2008. 10.1016/j.ica.2008.02.069.
Magnetic behaviour of Mn12 single-molecule magnet nanospheres
Carbonera, C.; Imaz, I.; Maspoch, D.; Ruiz-Molina, D.; Luis, F. Inorganica Chimica Acta; 361: 3951 - 3956. 2008. 10.1016/j.ica.2008.03.037.
Magnetism and magnetic resonance studies of single-molecule magnets in polymer matrices
van Slageren, J.; Dengler, S.; GÃ³mez-Segura, J.; Ruiz-Molina, D.; Dressel, M. Inorganica Chimica Acta; 361: 3714 - 3717. 2008. 10.1016/j.ica.2008.03.022.
pH-responsive fluorescent nanoarrays fabricated by direct-write parallel dip-pen nanolithography
Martínez-Otero, A.; Hernando, J.; Ruiz-Molina, D.; Maspoch, D. Small; 4: 2131 - 2135. 2008. 10.1002/smll.200800481.
Single-molecule magnet behaviour in metal-organic nanospheres generated by simple precipitation of Mn12O12 clusters
Imaz, I.; Luis, F.; Carbonera, C.; Ruiz-Molina, D.; Maspoch, D. Chemical Communications; : 1202 - 1204. 2008. 10.1039/b716071b.
Surface-structured molecular sensor for the optical detection of acidity
Martínez-Otero, A.; Evangelio, E.; Alibés, R.; Bourdelande, J.L.; Ruiz-Molina, D.; Busqué, F.; Hernando, J. Langmuir : the ACS journal of surfaces and colloids; 24: 2963 - 2966. 2008. 10.1021/la704072z.
Synthesis, X-ray structure and reactivity of a sterically protected azobisphenol ligand: On the quest for new multifunctional active ligands
Evangelio, E.; Saiz-Poseu, J.; Maspoch, D.; Wurst, K.; Busque, F.; Ruiz-Molina, D. European Journal of Inorganic Chemistry; : 2278 - 2285. 2008. 10.1002/ejic.200701339.
Valence tautomerism: More actors than just electroactive ligands and metal ions
Evangelio, E.; Ruiz-Molina, D. Comptes Rendus Chimie; 11: 1137 - 1154. 2008. 10.1016/j.crci.2008.09.007.
Valence-tautomeric metal-organic nanoparticles
Imaz, I.; Maspoch, D.; Rodríguez-Blanco, C.; Pérez-Falcón, J.M.; Campo, J.; Ruiz-Molina, D. Angewandte Chemie - International Edition; 47: 1857 - 1860. 2008. 10.1002/anie.200705263.

2007

Advances on the nanostructuration of magnetic molecules on surfaces: The case of single-molecule magnets (SMM)
Gómez-Segura, J.; Veciana, J.; Ruiz-Molina, D. Chemical Communications; : 3699 - 3707. 2007. 10.1039/b616352a.
First-row transition-metal complexes based on a carboxylate polychlorotriphenylmethyl radical: Trends in metal-radical exchange interactions
Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Hernández, J.M.; Lloret, F.; Tejada, J.; Rovira, C.; Veciana, J. Inorganic Chemistry; 46: 1627 - 1633. 2007. 10.1021/ic061815x.
High-frequency ESR and frequency domain magnetic resonance spectroscopic studies of single molecule magnets in frozen solution
El Hallak, F.; Van Slageren, J.; Gómez-Segura, J.; Ruiz-Molina, D.; Dressel, M. Physical Review B - Condensed Matter and Materials Physics; 75 2007. 10.1103/PhysRevB.75.104403.
New insights into the thermal stability of Mn12 clusters: The case of complex [Mn12O12(O2CCCH) 16(H2O)4]·3H2O and its thermolysis derived [Mn3(O2CCCH)6(H 2O)4]·2H2O complex
Gómez-Segura, J.; Campo, J.; Imaz, I.; Wurst, K.; Veciana, J.; Gerbier, P.; Ruiz-Molina, D. Dalton Transactions; : 2450 - 2456. 2007. 10.1039/b700298j.
New insights into the thermal stability of Mn12 clusters: The case of complex [Mn12O12(O2CC[triple bond, length as m-dash]CH)16(H2O)4]·3H2O and its thermolysis derived [Mn3(O2CC[triple bond, length as m-dash]CH)6(H2O)4]·2H2O complex
Jordi Gómez-Segura; Javier Campo; Inhar Imaz; Klaus Wurst; Jaume Veciana; Philippe Gerbiere; Daniel Ruiz-Molina Dalton Transactions; 2007. .
New insights into the thermal stability of Mn12clusters: The case of complex [Mn12O12(O2CCºCH)16 (H2O)4 ]*3H2O and its thermolysis derived [Mn3(O2CCºCH)6(H2O)4]*2H2O complex
Gómez-Segura J.; J. Campo; I. Imaz; K. Wurst; J. Veciana; P. Gerbier; D. Ruiz-Molina Journal of the Chemical Society - Dalton Transactions; 31: 2450 - 2456. 2007. .
Old materials with new tricks: multifunctional open-framework materials
D. Maspoch; D. Ruiz-Molina; J. Veciana Chemical Society Reviews; 2007. .
Self-assembly of carboxylic substituted PTM radicals: from weak ferromagnetic interactions to porous magnets
N. Roques; D. Maspoch; K. Wurst; D. Ruiz-Molina; C. Rovira; J. Veciana Polyhedron; 26: 1934. 2007. .
Solvent tuning from normal to inverted marcus region of intramolecular electron transfer in ferrocene-based organic radicals
Ratera, I.; Sporer, C.; Ruiz-Molina, D.; Ventosa, N.; Baggerman, J.; Brouwer, A.M.; Rovira, C.; Veciana, J. Journal of the American Chemical Society; 129: 6117 - 6129. 2007. 10.1021/ja066351g.
Structural and magnetic modulation of a purely organic open framework by selective guest inclusion
Maspoch, D.; Domingo, N.; Roques, N.; Wurst, K.; Tejada, J.; Rovira, C.; Ruiz-Molina, D.; Veciana, J. Chemistry - A European Journal; 13: 8153 - 8163. 2007. 10.1002/chem.200700353.

2006

2-D self-assembly of the bis(phthalocyaninato)terbium(III) single-molecule magnet studied by scanning tunnelling microscopy
Gómez-Segura, J.; Díez-Pérez, I.; Ishikawa, N.; Nakano, M.; Veciana, J.; Ruiz-Molina, D. Chemical Communications; : 2866 - 2868. 2006. 10.1039/b606276h.
A new hexaferrocene complex with a [M3(Î¿3-O)] 7+ core
Mereacre, V.; Nakano, M.; Gómez-Segura, J.; Imaz, I.; Sporer, C.; Wurst, K.; Veciana, J.; Turta, C.; Ruiz-Molina, D.; Jaitner, P. Inorganic Chemistry; 45: 10443 - 10445. 2006. 10.1021/ic061322s.
Controlled crystallization of Mn12 single-molecule magnets by compressed CO2 and its influence on the magnetization relaxation
Muntó, M.; Gómez-Segura, J.; Campo, J.; Nakano, M.; Ventosa, N.; Ruiz-Molina, D.; Veciana, J. Journal of Materials Chemistry; 16: 2612 - 2617. 2006. 10.1039/b603497g.
Influence of bridge topology and torsion on the intramolecular electron transfer
Lloveras, V.; Vidal-Gancedo, J.; Ruiz-Molina, D.; Figueira-Duarte, T.M.; Nierengarten, J.-F.; Veciana, J.; Rovira, C. Faraday Discussions; 131: 291 - 305. 2006. 10.1039/b506678f.
Ordered patterning of nanometric rings of single molecule magnets on polymers by lithographic control of demixing
Cavallini, M.; Gomez-Segura, J.; Albonetti, C.; Ruiz-Molina, D.; Veciana, J.; Biscarini, F. Journal of Physical Chemistry B; 110: 11607 - 11610. 2006. 10.1021/jp061231g.
Three-dimensional six-connecting organic building blocks based on polychlorotriphenylmethyl units - Synthesis, self-assembly, and magnetic properties
Roques, N.; Maspoch, D.; Wurst, K.; Ruiz-Molina, D.; Rovira, C.; Veciana, J. Chemistry - A European Journal; 12: 9238 - 9253. 2006. 10.1002/chem.200600447.

2005

An unusually stable trinuclear manganese(II) complex bearing bulk carboxylic radical ligands
Maspoch, D.; Gómez-Segura, J.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Rovira, C.; Tejada, J.; Veciana, J. Inorganic Chemistry; 44: 6936 - 6938. 2005. 10.1021/ic050977a.
Carboxylic-substituted polychlorotriphenylmethyl radicals, new organic building-blocks to design nanoporous magnetic molecular materials
Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Tejada, J.; Rovira, C.; Veciana, J. Comptes Rendus Chimie; 8: 1213 - 1225. 2005. 10.1016/j.crci.2005.02.020.
Coexistence of ferro- and antiferromagnetic interactions in a metal-organic radical-based (6,3)-helical network with large channels
Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Hernández, J.-M.; Vaughan, G.; Rovira, C.; Lloret, F.; Tejada, J.; Veciana, J. Chemical Communications; : 5035 - 5037. 2005. 10.1039/b505827a.
Ferrocene triphenylmethyl radical donor-acceptor compounds. Towards the development of multifunctional molecular switches
Sporer, C.; Ratera, I.; Wurst, K.; Vidal-Gancedo, J.; Ruiz-Molina, D.; Rovira, C.; Veciana, J. Arkivoc; 2005: 104 - 114. 2005. .
Hydrogen-bonded self-assemblies in a polychlorotriphenylmethyl radical derivative substituted with six meta-carboxylic acid groups
Roques, N.; Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Tejada, J.; Rovira, C.; Veciana, J. Chemical Communications; : 4801 - 4803. 2005. 10.1039/b508952b.
Long-Range ferromagnetism of Mn12 acetate single-molecule Magnets under a transverse magnetic field
Luis, F.; Campo, J.; Gómez, J.; McIntyre, G.J.; Luzón, J.; Ruiz-Molina, D. Physical Review Letters; 95 2005. 10.1103/PhysRevLett.95.227202.
Magnetic information storage on polymers by using patterned single-molecule magnets
Cavallini, M.; Gomez-Segura, J.; Ruiz-Molina, D.; Massi, M.; Albonetti, C.; Rovira, C.; Veciana, J.; Biscarini, F. Angewandte Chemie - International Edition; 44: 888 - 892. 2005. 10.1002/anie.200461554.
Self-organization of Mn12 single-molecule magnets into ring structures induced by breath-figures as templates
Gómez-Segura, J.; Kazakova, O.; Davies, J.; Josephs-Franks, P.; Veciana, J.; Ruiz-Molina, D. Chemical Communications; : 5615 - 5617. 2005. 10.1039/b509282e.
Trihaloacetic acids: An investigation of steric and inductive ligand effects on the synthesis of [Mn12O12(O2CCX 3)16(H2O)4] single-molecule magnets
GÃ³mez-Segura, J.; Lhotel, E.; Paulsen, C.; Luneau, D.; Wurst, K.; Veciana, J.; Ruiz-Molina, D.; Gerbier, P. New Journal of Chemistry; 29: 499 - 503. 2005. 10.1039/b411371c.
Valence tautomerism: New challenges for electroactive ligands
Evangelio, E.; Ruiz-Molina, D. European Journal of Inorganic Chemistry; : 2957 - 2971. 2005. 10.1002/ejic.200500323.

2004

A Molecular multiproperty switching array based on the redox behavior of a ferrocenyl polychlorotriphenylmethyl radical
Sporer, C.; Ratera, I.; Ruiz-Molina, D.; Zhao, Y.; Vidal-Gancedo, J.; Wurst, K.; Jaitner, P.; Clays, K.; Persoons, A.; Rovira, C.; Veciana, J. Angewandte Chemie - International Edition; 43: 5266 - 5268. 2004. 10.1002/anie.200454150.
A new (63)·(69.81) non-interpenetrated paramagnetic network with helical nanochannels based on a tricarboxylic perchlorotriphenylmethyl radical
Maspoch, D.; Ruiz-Molina, D.; Wurst, K.; Rovira, C.; Veciana, J. Chemical Communications; 10: 1164 - 1165. 2004. .
A Robust Nanocontainer Based on a Pure Organic Free Radical
Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Tejada, J.; Rovira, C.; Veciana, J. Journal of the American Chemical Society; 126: 730 - 731. 2004. 10.1021/ja038988v.
A robust purely organic nanoporous magnet
Maspoch, D.; Domingo, N.; Ruiz-Molina, D.; Wurst, K.; Vaughan, G.; Tejada, J.; Rovira, C.; Veciana, J. Angewandte Chemie - International Edition; 43: 1828 - 1832. 2004. 10.1002/anie.200353358.
Chiral, single-molecule nanomagnets: Synthesis, magnetic characterization and natural and magnetic circular dichroism
Gerbier, P.; Domingo, N.; Gómez-Segura, J.; Ruiz-Molina, D.; Amabilino, D.B.; Tejada, J.; Williamson, B.E.; Veciana, J. Journal of Materials Chemistry; 14: 2455 - 2460. 2004. 10.1039/b403062a.
EPR Characterization of a Nanoporous Metal-Organic Framework Exhibiting a Bulk Magnetic Ordering
D. Maspoch; J. Vidal-Gancedo; D. Ruiz-Molina; C. Rovira; J. Veciana Journal of Physics and Chemistry of Solids; 65: 819. 2004. 10.1016/j/jpcs.2003.11.026.
Magnetic nanoporous coordination polymers
Maspoch, D.; Ruiz-Molina, D.; Veciana, J. Journal of Materials Chemistry; 14: 2713 - 2723. 2004. 10.1039/b407169g.
Magnetism of isolated Mn12 single-molecule magnets detected by magnetic circular dichroism: Observation of spin tunneling with a magneto-optical technique
Domingo, N.; Williamson, B.E.; Gómez-Segura, J.; Gerbier, Ph.; Ruiz-Molina, D.; Amabilino, D.B.; Veciana, J.; Tejada, J. Physical Review B; 69: 524051 - 524054. 2004. .
Magneto-Structural Characterization of Metallocene-Bridged Nitronyl Nitroxide Diradicals by X-Ray, Magnetic Measurements, Solid-state NMR Spectroscopy, and Ab Initio Calculations
Sporer, C.; Heise, H.; Wurst, K.; Ruiz-Molina, D.; Kopacka, H.; Jaitner, P.; Köhler, F.; Novoa, J.J.; Veciana, J. Chemistry - A European Journal; 10: 1355 - 1365. 2004. 10.1002/chem.200305349.
Open-shell channel-like salts formed by the supramolecular assembly of a tricarboxylated perchlorotriphenylmethyl radical and a [Co(bpy) 3]2+ cation
Maspoch, D.; Ruiz-Molina, D.; Wurst, K.; Vaughan, G.; Domingo, N.; Tejada, J.; Rovira, C.; Veciana, J. CrystEngComm; 6: 573 - 578. 2004. 10.1039/b410810h.
Supramolecular Photomagnetic Materials: Photoinduced Dimerization of Ferrocene-Based Polychlorotriphenylmethyl Radicals
Ratera, I.; Ruiz-Molina, D.; Vidal-Gancedo, J.; Novoa, J.J.; Wurst, K.; Letard, J.-F.; Rovira, C.; Veciana, J. Chemistry - A European Journal; 10: 603 - 616. 2004. .
Synthesis, structural and magnetic properties of a series of copper(ii) complexes containing a monocarboxylated perchlorotriphenylmethyl radical as a coordinating open-shell ligand
Maspoch, D.; Ruiz-Molina, D.; Wurst, K.; Vidal-Gancedo, J.; Rovira, C.; Veciana, J. Dalton Transactions; : 1073 - 1082. 2004. .
Synthesis, X-ray Structure, EPR and Optical Properties of a Ferrocene Substituted Polychlorotriphenylmethyl Radical
C. Sporer; I. Ratera; D. Ruiz-Molina; J. Vidal-Gancedo; K. Wurst; P. Jaitner; C. Rovira; J. Veciana Journal of Physics and Chemistry of Solids; 65: 753. 2004. 10.1016/j.jpcs.2003.11.012.