Staff directory Daniel Ruiz Molina

Daniel Ruiz Molina

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

Publications

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.

    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.


  • 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.

    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


  • 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.

    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


  • 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.

    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.


  • 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.

    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.


  • 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.

    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


  • 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.

    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.


  • 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.

    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


  • 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.

    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.


  • 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.

    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.


2017

  • 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.


  • 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.


  • 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.


  • 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


  • 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.


  • 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).


  • 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


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.


  • 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.


  • 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.


  • 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.


  • 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.


  • 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.


  • 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


  • 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.


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.


  • 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.


  • 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.


  • 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.


2014

  • 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


  • 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.; Gómez-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(ο3-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

    Gómez-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.