Publications
-
Antigen-specific immunotherapy combined with a regenerative drug in the treatment of experimental type 1 diabetes
Villalba A., Rodriguez-Fernandez S., Perna-Barrull D., Ampudia R.-M., Gomez-Muñoz L., Pujol-Autonell I., Aguilera E., Risueño R.M., Cano-Sarabia M., Maspoch D., Vázquez F., Vives-Pi M. Scientific Reports; 10 (1, 18927) 2020. 10.1038/s41598-020-76041-1. IF: 3.998
Type 1 diabetes is an autoimmune disease caused by the destruction of the insulin-producing β-cells. To revert type 1 diabetes, the suppression of the autoimmune attack should be combined with a β-cell replacement strategy. It has been previously demonstrated that liraglutide, a glucagon-like peptide-1 receptor agonist, restores β-cell mass in type 1 diabetes, via α-cell transdifferentiation and neogenesis. We report here that treatment with liraglutide does not prevent type 1 diabetes in the spontaneous non-obese diabetic (NOD) mouse model, but it tends to reduce leukocytic islet infiltration. However, in combination with an immunotherapy based on tolerogenic liposomes, it is effective in ameliorating hyperglycaemia in diabetic NOD mice. Importantly, liraglutide is not detrimental for the tolerogenic effect that liposomes exert on dendritic cells from patients with type 1 diabetes in terms of membrane expression of molecules involved in antigen presentation, immunoregulation and activation. Moreover, the in vivo effect of the combined therapy was tested in mice humanised with peripheral blood mononuclear cells from patients with type 1 diabetes, showing no adverse effects in leukocyte subsets. In conclusion, the combination therapy with liraglutide and a liposome-based immunotherapy is a promising candidate strategy for type 1 diabetes. © 2020, The Author(s).
-
Biomimetic Synthesis of Sub-20 nm Covalent Organic Frameworks in Water
Franco C., Rodríguez-San-Miguel D., Sorrenti A., Sevim S., Pons R., Platero-Prats A.E., Pavlovic M., Szilágyi I., Ruiz Gonzalez M.L., González-Calbet J.M., Bochicchio D., Pesce L., Pavan G.M., Imaz I., Cano-Sarabia M., Maspoch D., Pané S., De Mello A.J., Zamora F., Puigmartí-Luis J. Journal of the American Chemical Society; 142 (7): 3540 - 3547. 2020. 10.1021/jacs.9b12389. IF: 14.612
Covalent organic frameworks (COFs) are commonly synthesized under harsh conditions yielding unprocessable powders. Control in their crystallization process and growth has been limited to studies conducted in hazardous organic solvents. Herein, we report a one-pot synthetic method that yields stable aqueous colloidal solutions of sub-20 nm crystalline imine-based COF particles at room temperature and ambient pressure. Additionally, through the combination of experimental and computational studies, we investigated the mechanisms and forces underlying the formation of such imine-based COF colloids in water. Further, we show that our method can be used to process the colloidal solution into 2D and 3D COF shapes as well as to generate a COF ink that can be directly printed onto surfaces. These findings should open new vistas in COF chemistry, enabling new application areas. Copyright © 2020 American Chemical Society.
-
Dynamic porous coordination polymers built-up from flexible 4,4′-dithiodibenzoate and rigid N-based ligands
Jarrah N., Troyano J., Carné-Sánchez A., Imaz I., Tangestaninejad S., Moghadam M., Maspoch D. Dalton Transactions; 49 (37): 13142 - 13151. 2020. 10.1039/d0dt02411b. IF: 4.174
Herein we report the design, synthesis, structural characterisation and functional testing of a series of Cu(ii) coordination polymers containing flexible 4,4′-dithiodibenzoate ligand (4,4′-DTBA), with or without auxiliary N-donor ligands. Reaction of Cu(ii) with 4,4′-DTBA yielded a 1D coordination polymer (1) based on Cu(ii) paddlewheel units connected by 4,4′-DTBA, to form cyclic loop chains with intramolecular voids that exhibit reversible structural transformations upon subsequent solvent exchange in methanol to afford a new, crystalline, permanently-porous structure (1′). However, when the same reaction was run with pyridine, it formed a porous 2D coordination polymer (2). We have attributed the difference in dimensionality seen in the two products to the coordination of pyridine on the axial site of the Cu(ii) paddle-wheel, which forces flexible 4,4′-DTBA to adopt a different conformation. Reactions in the presence of 4,4′-bipyridine (4,4′-bpy) afforded two new, flexible, 2D coordination polymers (3 4). Lower concentrations of 4,4′-bpy afforded a structure (3) built from 1D chains analogous to those in 1 and connected through 4,4′-bpy linkers coordinated to the axial positions. Interestingly, 3 showed reversible structural transformations triggered by either solvent exchange or thermal treatment, each of which yielded a new crystalline and permanently porous phase (3′). Finally, use of higher concentrations of 4,4′-bpy led to a coordination polymer (4) based on a distorted CuO3N2 trigonal bipyramid, rather than on the Cu(ii) paddlewheel. The connection of these motifs by 4,4′-DTBA resulted in a zig-zag 1D chain connected through 4,4′-bpy ligands to form a porous 2D network. Interestingly, 4 also underwent reversible thermal transformation to yield a microporous coordination polymer (4′). © The Royal Society of Chemistry.
-
Enzyme-Powered Porous Micromotors Built from a Hierarchical Micro- And Mesoporous UiO-Type Metal-Organic Framework
Yang Y., Arqué X., Patiño T., Guillerm V., Blersch P.-R., Pérez-Carvajal J., Imaz I., Maspoch D., Sánchez S. Journal of the American Chemical Society; 142 (50): 20962 - 20967. 2020. 10.1021/jacs.0c11061. IF: 14.612
Here, we report the design, synthesis, and functional testing of enzyme-powered porous micromotors built from a metal-organic framework (MOF). We began by subjecting a presynthesized microporous UiO-type MOF to ozonolysis, to confer it with mesopores sufficiently large to adsorb and host the enzyme catalase (size: 6-10 nm). We then encapsulated catalase inside the mesopores, observing that they are hosted in those mesopores located at the subsurface of the MOF crystals. In the presence of H2O2 fuel, MOF motors (or MOFtors) exhibit jet-like propulsion enabled by enzymatic generation of oxygen bubbles. Moreover, thanks to their hierarchical pore system, the MOFtors retain sufficient free space for adsorption of additional targeted species, which we validated by testing a MOFtor for removal of rhodamine B during self-propulsion. © 2020 American Chemical Society.
-
Green synthesis of imine-based covalent organic frameworks in water
Martín-Illán J.Á., Rodríguez-San-Miguel D., Rodríguez-San-Miguel D., Franco C., Imaz I., Maspoch D., Maspoch D., Puigmartí-Luis J., Zamora F., Zamora F., Zamora F., Zamora F. Chemical Communications; 56 (49): 6704 - 6707. 2020. 10.1039/d0cc02033h. IF: 5.996
Dynamic covalent bonds have been advantageously used to direct the synthesis of crystalline porous covalent organic frameworks (COFs). Unlike the standard synthetic protocols that involve harsh conditions, this work provides a high-yield "one-pot"green synthesis of imine-based COFs in water. Additionally, this aqueous synthesis can be performed under microwave conditions, considerably reducing the reaction time. © The Royal Society of Chemistry.
-
LipoBots: Using Liposomal Vesicles as Protective Shell of Urease-Based Nanomotors
Hortelão A.C., García-Jimeno S., Cano-Sarabia M., Patiño T., Maspoch D., Sanchez S. Advanced Functional Materials; 30 (42, 2002767) 2020. 10.1002/adfm.202002767. IF: 16.836
Developing self-powered nanomotors made of biocompatible and functional components is of paramount importance in future biomedical applications. Herein, the functional features of LipoBots (LBs) composed of a liposomal carrier containing urease enzymes for propulsion, including their protective properties against acidic conditions and their on-demand triggered activation, are reported. Given the functional nature of liposomes, enzymes can be either encapsulated or coated on the surface of the vesicles. The influence of the location of urease on motion dynamics is first studied, finding that the surface-urease LBs undergo self-propulsion whereas the encapsulated-urease LBs do not. However, adding a percolating agent present in the bile salts to the encapsulated-urease LBs triggers active motion. Moreover, it is found that when both types of nanomotors are exposed to a medium of similar pH found in the stomach, the surface-urease LBs lose activity and motion capabilities, while the encapsulated-urease LBs retain activity and mobility. The results for the protection enzyme activity through encapsulation within liposomes and in situ triggering of the motion of LBs upon exposure to bile salts may open new avenues for the use of liposome-based nanomotors in drug delivery, for example, in the gastrointestinal tract, where bile salts are naturally present in the intestine. © 2020 Wiley-VCH GmbH
-
MOF-Beads Containing Inorganic Nanoparticles for the Simultaneous Removal of Multiple Heavy Metals from Water
Boix G., Troyano J., Garzón-Tovar L., Camur C., Bermejo N., Yazdi A., Piella J., Bastus N.G., Puntes V.F., Imaz I., Maspoch D. ACS Applied Materials and Interfaces; 12 (9): 10554 - 10562. 2020. 10.1021/acsami.9b23206. IF: 8.758
Pollution of water with heavy metals is a global environmental problem whose impact is especially severe in developing countries. Among water-purification methods, adsorption of heavy metals has proven to be simple, versatile, and cost-effective. However, there is still a need to develop adsorbents with a capacity to remove multiple metal pollutants from the same water sample. Herein, we report the complementary adsorption capacities of metal-organic frameworks (here, UiO-66 and UiO-66-(SH)2) and inorganic nanoparticles (iNPs; here, cerium-oxide NPs) into composite materials. These adsorbents, which are spherical microbeads generated in one step by continuous-flow spray-drying, efficiently and simultaneously remove multiple heavy metals from water, including As(III and V), Cd(II), Cr(III and VI), Cu(II), Pb(II), and Hg(II). We further show that these microbeads can be used as a packing material in a prototype of a continuous-flow water treatment system, in which they retain their metal-removal capacities upon regeneration with a gentle acidic treatment. As proof-of-concept, we evaluated these adsorbents for purification of laboratory water samples prepared to independently recapitulate each of two strongly polluted rivers: the Bone (Indonesia) and Buringanga (Bangladesh) rivers. In both cases, our microbeads reduced the levels of all the metal contaminants to below the corresponding permissible limits established by the World Health Organization (WHO). Moreover, we demonstrated the capacity of these microbeads to lower levels of Cr(VI) in a water sample collected from the Sarno River (Italy). Finally, to create adsorbents that could be magnetically recovered following their use in water purification, we extended our spray-drying technique to simultaneously incorporate two types of iNPs (CeO2 and Fe3O4) into UiO-66-(SH)2, obtaining CeO2/Fe3O4@UiO-66-(SH)2 microbeads that adsorb heavy metals and are magnetically responsive. Copyright © 2020 American Chemical Society.
-
Molecular Approach for Engineering Interfacial Interactions in Magnetic/Topological Insulator Heterostructures
Cuxart M.G., Valbuena M.A., Robles R., Moreno C., Bonell F., Sauthier G., Imaz I., Xu H., Nistor C., Barla A., Gargiani P., Valvidares M., Maspoch D., Gambardella P., Valenzuela S.O., Mugarza A. ACS Nano; 14 (5): 6285 - 6294. 2020. 10.1021/acsnano.0c02498. IF: 14.588
Controlling interfacial interactions in magnetic/topological insulator heterostructures is a major challenge for the emergence of novel spin-dependent electronic phenomena. As for any rational design of heterostructures that rely on proximity effects, one should ideally retain the overall properties of each component while tuning interactions at the interface. However, in most inorganic interfaces, interactions are too strong, consequently perturbing, and even quenching, both the magnetic moment and the topological surface states at each side of the interface. Here, we show that these properties can be preserved using ligand chemistry to tune the interaction of magnetic ions with the surface states. By depositing Co-based porphyrin and phthalocyanine monolayers on the surface of Bi2Te3 thin films, robust interfaces are formed that preserve undoped topological surface states as well as the pristine magnetic moment of the divalent Co ions. The selected ligands allow us to tune the interfacial hybridization within this weak interaction regime. These results, which are in stark contrast with the observed suppression of the surface state at the first quintuple layer of Bi2Se3 induced by the interaction with Co phthalocyanines, demonstrate the capability of planar metal-organic molecules to span interactions from the strong to the weak limit. © 2020 American Chemical Society.
-
Net-Clipping: An Approach to Deduce the Topology of Metal-Organic Frameworks Built with Zigzag Ligands
Ortín-Rubio B., Ghasempour H., Guillerm V., Morsali A., Juanhuix J., Imaz I., Maspoch D., Maspoch D. Journal of the American Chemical Society; 142 (20): 9135 - 9140. 2020. 10.1021/jacs.0c03404. IF: 14.612
Herein we propose a new approach for deducing the topology of metal-organic frameworks (MOFs) assembled from organic ligands of low symmetry, which we call net-clipping. It is based on the construction of nets by rational deconstruction of edge-transitive nets comprising higher-connected molecular building blocks (MBBs). We have applied net-clipping to predict the topologies of MOFs containing zigzag ligands. To this end, we derived 2-connected (2-c) zigzag ligands from 4-c square-like MBBs by first splitting the 4-c nodes into two 3-c nodes and then clipping their two diagonally connecting groups. We demonstrate that, when this approach is applied to the 17 edge-transitive nets containing square-like 4-c MBBs, net-clipping leads to generation of 10 nets with different underlying topologies. Moreover, we report that literature and experimental research corroborate successful implementation of our approach. As proof-of-concept, we employed net-clipping to form three new MOFs built with zigzag ligands, each of which exhibits the deduced topology. © 2020 American Chemical Society.
-
Preclinical evaluation of antigen-specific nanotherapy based on phosphatidylserine-liposomes for type 1 diabetes
Villalba A., Rodriguez-Fernandez S., Ampudia R.-M., Cano-Sarabia M., Perna-Barrull D., Bertran-Cobo C., Ehrenberg C., Maspoch D., Vives-Pi M. Artificial Cells, Nanomedicine and Biotechnology; 48 (1): 77 - 83. 2020. 10.1080/21691401.2019.1699812. IF: 3.343
Type 1 diabetes (T1D) is an autoimmune disease caused by the destruction of insulin-producing cells. Due to the ability of apoptotic cells clearance to induce tolerance, we previously generated liposomes rich in phophatidylserine (PS) –a feature of apoptotic cells– loaded with insulin peptides to mimic apoptotic beta-cells. PS-liposomes arrested autoimmunity in experimental T1D through the induction of tolerance. The aim of this study was to investigate the potential of several peptides from different T1D autoantigens encapsulated in (PS)-liposomes for T1D prevention and to assess its safety. T1D autoantigens (Insulin, C-peptide, GAD65 and IA2) were encapsulated in PS-liposomes. Liposomes were administered to the 'gold-standard' model for the study of autoimmune T1D, the Non-Obese Diabetic mouse, that spontaneously develop the disease. Safety and toxicity of liposomes were also determined. Only PS-liposomes encapsulating insulin peptides decrease T1D incidence in the Non-Obese Diabetic mouse model. Disease prevention correlates with a decrease in the severity of the autoimmune islet destruction driven by leukocytes. PS-liposomes neither showed toxic effect nor secondary complications. Among the here referred autoantigens, insulin peptides are the best candidates to be encapsulated in liposomes, like an artificial apoptotic cell, for the arrest of autoimmunity in T1D in a safe manner. © 2019, © 2019 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group.
-
Spray-Drying Synthesis of MOFs, COFs, and Related Composites
Troyano J., Çamur C., Garzón-Tovar L., Carné-Sánchez A., Imaz I., Maspoch D., Maspoch D. Accounts of Chemical Research; 53 (6): 1206 - 1217. 2020. 10.1021/acs.accounts.0c00133. IF: 20.832
ConspectusMetal-organic frameworks (MOFs) and covalent organic frameworks (COFs) are among the most attractive porous materials today. They exhibit outstanding porosity for countless applications such as gas storage, CO2 capture, gas separation, sensing, drug delivery, and catalysis. Moreover, researchers have recently begun to combine MOFs or COFs with other functional materials to obtain composites that boast the respective strengths, and mitigate the respective weaknesses, of each component, enabling enhanced performance in many of the aforementioned applications. Accordingly, development of methods for fabrication of MOFs, COFs, and related composites is important for facilitating adoption of these materials in industry. One promising synthetic technique is spray-drying, which is already well-integrated in manufacturing processes for diverse sectors. It enables rapid, continuous and scalable production of dry microspherical powders in a single step, leading to lower fabrication costs and shorter production times compared to traditional methods.In this Account, we outline our ongoing work on spray-drying synthesis of crystalline porous MOFs, COFs, and related composites. Versatile and tunable, spray-drying can be adapted to perform reactions involving coordination and covalent chemistry for the synthesis of micrometer spherical beads/superstructures of MOFs and COFs. Likewise, MOF- and COF-based composites can be synthesized using similar conditions as those for pure MOFs or COFs, through the simple introduction of additional functional materials into the feed precursor solution or colloid. Interestingly, spray-drying can also be done in water, thus providing the basis for its use as a scalable green method for industrial fabrication of these materials. To date, spray-drying has already been scaled up for pilot production (kilogram scale) of MOFs. © 2020 American Chemical Society.
-
Structural Deterioration of Well-Faceted MOFs upon H2S Exposure and Its Effect in the Adsorption Performance
Reljic S., Broto-Ribas A., Cuadrado-Collados C., Jardim E.O., Maspoch D., Imaz I., Silvestre-Albero J. Chemistry - A European Journal; 26 (71): 17110 - 17119. 2020. 10.1002/chem.202002473. IF: 4.857
The structural deterioration of archetypical, well-faceted metal–organic frameworks (MOFs) has been evaluated upon exposure to an acidic environment (H2S). Experimental results show that the structural damage highly depends on the nature of the hybrid network (e.g., softness of the metal ions, hydrophilic properties, among others) and the crystallographic orientation of the exposed facets. Microscopy images show that HKUST-1 with well-defined octahedral (111) facets is completely deteriorated, ZIF-8 with preferentially exposed (110) facets exhibits a large external deterioration with the development of holes or cavities in the mesoporous range, whereas UiO-66-NH2 with (111) exposed facets, and PCN-250 with (100) facets does not reflect any sign of surface damage. Despite the selectivity in the external deterioration, X-ray diffraction and gas adsorption measurements confirm that indeed all MOFs suffer an important internal deterioration, these effects being more severe for MOFs based on softer cations (e.g., Cu-based HKUST-1 and Fe-based PCN-250). These structural changes have inevitable important effects in the final adsorption performance for CO2 and CH4 at low and high pressures. © 2020 Wiley-VCH GmbH
-
Supramolecular Fullerene Sponges as Catalytic Masks for Regioselective Functionalization of C60
Fuertes-Espinosa C., García-Simón C., Pujals M., Garcia-Borràs M., Gómez L., Parella T., Juanhuix J., Imaz I., Maspoch D., Costas M., Ribas X. Chem; 6 (1): 169 - 186. 2020. 10.1016/j.chempr.2019.10.010. IF: 19.375
Isomer-pure poly-functionalized fullerenes are required to boost the development of fullerene chemistry in all fields. On a general basis, multi-adduct mixtures with uncontrolled regioselectivity are obtained, and the use of chromatographic purification is prohibitively costly and time consuming, especially in the production of solar cells. Single-isomer poly-functionalized fullerenes are only accessible via stoichiometric, multistep paths entailing protecting-unprotecting sequences. Herein, a nanocapsule is used as a supramolecular tetragonal prismatic mask to exert full control on the reactivity and the equatorial regioselectivity of Bingel-Hirsch cyclopropanation reactions of a confined C60 guest. Thus, equatorial bis-, tris-, and tetrakis-C60 homo-adducts are exclusively obtained in a stepwise manner. Furthermore, isomer-pure equatorial hetero-tetrakis-adducts or hetero-Th-hexakis-adducts are synthesized at will in one-pot synthesis for the first time. This work provides a synthetically valuable path to produce a plethora of new pure-isomer poly-functionalized C60-based compounds as candidates for testing in solar cell devices and biomedical applications. Video Abstract: The supramolecular mask protocol is a significant step forward for the regioselective functionalization of fullerenes. The exquisite ability to form pure-isomer poly-functionalized C60 adducts, overcoming tedious and non-practical chromatographic separations, allows for their direct testing in solar cell prototypes. Furthermore, the supramolecular mask strategy can be applied to C70 or higher fullerenes, opening a plethora of poly-functionalized fullerene derivatives to be synthesized and tested. Moreover, apart from the nucleophilic cyclopropanations reported herein, the protocol is currently being expanded to Diels-Alder (DA), 1,3-dipolar cycloadditions and PC60BM-type cyclopropanations, thus enabling a variety of regioselective functionalization reactions. This supramolecular mask strategy can help the discovery of the next generation of improved solar cells (organic or perovskite based) or new drug candidates. An unprecedented and straightforward supramolecular mask strategy to prepare exclusively equatorial bis-, tris-, and tetrakis-cyclopropanated-C60 Bingel-Hirsch derivatives is reported. By taking advantage of the high affinity for fullerene of tetragonal prismatic supramolecular cages, a highly stable C60⊂1a·(BArF)8 host-guest complex is submitted to Bingel-Hirsch cyclopropanation reaction conditions. Regioselectivity is strictly dictated by the four cross-shaped apertures of the nanocapsule in a controlled fashion. Moreover, stepwise-cyclopropanated adducts up to tetrakis additions are obtained in excellent yields and purities. © 2019 Elsevier Inc.
-
Ultrathin Films of Porous Metal–Organic Polyhedra for Gas Separation
Andrés M.A., Carné-Sánchez A., Sánchez-Laínez J., Roubeau O., Coronas J., Maspoch D., Gascón I. Chemistry - A European Journal; 26 (1): 143 - 147. 2020. 10.1002/chem.201904141. IF: 4.857
Ultrathin films of a robust RhII-based porous metal–organic polyhedra (MOP) have been obtained. Homogeneous and compact monolayer films (ca. 2.5 nm thick) were first formed at the air–water interface, deposited onto different substrates and characterized using spectroscopic methods, scanning transmission electron microscopy and atomic force microscopy. As a proof of concept, the gas separation performance of MOP-supported membranes has also been evaluated. Selective MOP ultrathin films (thickness ca. 60 nm) exhibit remarkable CO2 permeance and CO2/N2 selectivity, demonstrating the great combined potential of MOP and Langmuir-based techniques in separation technologies. © 2020 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim
