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Demand continues for processing methods to shape covalent organic frameworks (COFs) into macroscopic objects that are needed for their practical applications. Herein, a simple compression method to prepare large-scale, free-standing homogeneous and porous imine-based COF-membranes with dimensions in the centimeter range and excellent mechanical properties is reported. This method entails the compression of imine-based COF-aerogels, which undergo a morphological change from an elastic to plastic material. The COF-membranes fabricated upon compression show good performances for the separation of gas mixtures of industrial interest, N2/CO2 and CH4/CO2. It is believed that the new procedure paves the way to a broader range of COF-membranes., This work was supported by the Spanish MINECO (PID2019-106268GB-C31, PID2019-106268GB-C32, PCI2018-093081, and RTI2018-095622-B-I00), the Catalan AGAUR (project 2017 SGR 238), and through the “María de Maeztu” Programme for Units of Excellence in R&D (CEX2018-000805-M). It was also funded by the CERCA Program/Generalitat de Catalunya. ICN2 was supported by the Severo Ochoa program from the Spanish MINECO (Grant No. SEV-2017-0706). Y.C. and D.Z. acknowledge the National Research Foundation Singapore (NRF2018-NRF-ANR007 POCEMON) and the Ministry of Education – Singapore (MOE2018-T2-2-148, MOE2019-T2-1-093) for their financial support of this project.

Figure S1. Effect of rHDL-rApoJ or free rApoJ treatment in the levels of mouse ApoJ in brain homogenates and plasma from treated mice, determined by ELISA. Data are expressed as the mean ± SEM. N = 3–4/group. Figure S2. Effect of rHDL-rApoJ or free rApoJ treatment in the expression of full-length APP protein and the processing of APP through α-, β-, and γ secretases. a) Representative Western blots showing the relative amount of full-length APP, sAPPα, sAPPβ, and CTF-APP. Relative quantification of b) full-length APP, c) sAPPα, d) sAPPβ, and e) CTF-APP levels after treatments. Data are expressed as the mean ± SEM. N = 6/group. Table S1. List of abbreviation of tested inflammatory molecules by multiplexed ELISA. (DOCX 302 kb)

Herein, we exploit the well-known swelling behaviour of metal–organic frameworks (MOFs) to create a selffolding polymer film. Namely, we show that incorporating crystals of the flexible MOF MIL-88A into a polyvinylidene difluoride (PVDF) matrix affords a polymer composite film that undergoes reversible shape transformations upon exposure to polar solvents and vapours. Since the self-folding properties of this film correlate directly with the swelling properties of the MIL-88A crystals, it selectively bends to certain solvents and its degree of folding can be controlled by controlling the relative humidity. Moreover, it shows a shapememory effect at relative humidity values from 60% to 90%. As proof of concept, we demonstrate that these composite films can lift cargo and can be used to assemble 3D structures from 2D patterns. Our strategy is a straightforward method for designing autonomous soft materials with folding properties that can be tuned by judicious choice of the constituent flexible MOF. Proyecto del MINECO MAT2013-41836-R y de la Junta de Andalucía P12-FQM-1656

Altres ajuts: Comunidad de Madrid project S2013/MIT-2740 (PHAMA_2.0). CERCA Programme/Generalitat de Catalunya Self-assembly of particles into long-range, three-dimensional, ordered superstructures is crucial for the design of a variety of materials, including plasmonic sensing materials, energy or gas storage systems, catalysts and photonic crystals. Here, we have combined experimental and simulation data to show that truncated rhombic dodecahedral particles of the metal-organic framework (MOF) ZIF-8 can self-assemble into millimetre-sized superstructures with an underlying three-dimensional rhombohedral lattice that behave as photonic crystals. Those superstructures feature a photonic bandgap that can be tuned by controlling the size of the ZIF-8 particles and is also responsive to the adsorption of guest substances in the micropores of the ZIF-8 particles. In addition, superstructures with different lattices can also be assembled by tuning the truncation of ZIF-8 particles, or by using octahedral UiO-66 MOF particles instead. These well-ordered, sub-micrometre-sized superstructures might ultimately facilitate the design of three-dimensional photonic materials for applications in sensing.

Resumen del póster presentado al 1st Workshop Spain-Taiwan: "2D Materials and Interfaces for Spintronics", celebrado en Barcelona (España) del 23 al 25 de octubre de 2017., In topological insulators (TIs), long-range interactions between magnetic dopants mediated by the topological surface states can give rise to exotic phenomena such as the quantum anomalous Hall effect (QAHE) and dissipationless spin polarized edge currents. Such interactions, however, only occur under specific conditions of magnetic moment, anisotropy, and exchange coupling with the surrounding electron bath. Here we propose the use of metalorganic networks as an alternative strategy for tuning the electronic and magnetic interaction between the magnetic impurity and the substrate. The electronic and magnetic properties of TI surfaces modified by Brominated Cobalt tetraphenyl-porphyrin (4Br-CoTPP) networks are studied by combining Angle Resolved Photoemission Spectroscopy (ARPES) with X-Ray Magnetic Circular Dichroism (XMCD) measurements. ARPES measurements reveal that the topological surface state (TSS) is not quenched upon adsorption of slightly more than 1 ML 4Br-CoTPP in contrast with previous ARPES in Cobalt phthalocyanine/TI interfaces. The weaker interaction between the molecular layer and the substrate is confirmed by XMCD measurements where a strong in-plane magnetic moment is preserved. This ligand-mediated tuneability of interfacial interactions, together with the well-known capability of controlling magnetic anisotropy, makes the use of metalorganic molecules a promising route for engineering the electronic and magnetic properties of hybrid TI-based heterostructures.

A critical bottleneck for the use of metal-organic frameworks (MOFs) as drug delivery systems has been allowing them to reach their intracellular targets without being degraded in the acidic environment of the lysosomes. Cells take up particles by endocytosis through multiple biochemical pathways, and the fate of these particles depends on these routes of entry. Here, we show the effect of functional group incorporation into a series of Zr-based MOFs on their endocytosis mechanisms, allowing us to design an efficient drug delivery system. In particular, naphthalene-2,6-dicarboxylic acid and 4,4'-biphenyldicarboxylic acid ligands promote entry through the caveolin -pathway, allowing the particles to avoid lysosomal degradation and be delivered into the cytosol and enhancing their therapeutic activity when loaded with drugs.

Resumen del trabajo presentado al VIII International Congress on Analytical Nanoscience and Nanotechnology, celebrado en Barcelona (España) del 3 al 5 de julio de 2017., Despite the strong advances in the field of sensing and analytical techniques, the specific and fast control of a large number of environmental pollutants is still challenging. This is mainly due to the lack of analytical tools which, in addition to being fast, accurate and reliable, have an affordable cost and, more importantly, bare selective. For this reason, we have developed a novel photonic nanosensor, using a new class of nanoporous materials, the so-called Metal-Organic Frameworks (MOFs), as receptors for the rapid and selective detection of carbon dioxide as a control parameter for environmental monitoring. The nanosensor transducer is based on highly sensitive heteromodal waveguides and the receptors are transparent nanoZIF-8, made by zinc ions clusters coordinated by four imidazolate rings. The MOF layer is deposited by spin-coating and permanently attached to the sensor surface through a PDMS layer (Figure 1). Preliminary results show a limit of detection around 1% of CO2 and selectivity for CO2 versus N2. Each measure-regeneration cycle takes less than a minute. The process is reversible and the sensor surface is stable for more than one month.

Resumen del trabajo presentado al 1st Workshop Spain-Taiwan: "2D Materials and Interfaces for Spintronics", celebrado en Barcelona (España) del 23 al 25 de octubre de 2017.-- et al., Spin-Orbit Coupling (SOC) is at the origin of important new phenomena in materials such as heavy metal surface alloys with strong Rashba interaction and topological insulators (TIs), both with evident and promising applications in spintronics. Of special relevance are the emergent phenomena derived from the magnetic interactions in ferromagnetic (FM)/SOC interfaces. The Rashba and topological surface states can be used efficiently for reversing the magnetization of FM thin films by charge currents via spin transfer torque and for spin to charge conversion as a result of an inverse Edelstein effect. Besides, in topological insulators (TIs), long-range interactions between magnetic dopants mediated by the topological surface states can give rise to exotic phenomena such as the quantum anomalous Hall effect and dissipationless spin polarized edge currents. Despite their experimental demonstrations, an atomistic understanding of these phenomena is still missing. In this work we present a systematic experimental investigation on the magnetic properties in model FM/SOC interfaces. In a first step we will use 3d transition metals (TM) adatoms as magnetic dopants on the substitutional BiAg2 surface alloy grown on Ag(111). Through the controlled deposition of a series of TM impurities at cryogenic temperatures we systematically study different magnetic configurations. The influence of the SOC interaction, impurity adsorption sites and surface structure on the magnetic anisotropy is analyzed correlating experimental (XMCD) and theoretical (DFT) data. On the other side, we try to overcome the experimental difficulties of controlling the magnetic ground state and anisotropy of 3d transition metal impurities by using metalorganic molecular networks (porphyrin based) as an alternative strategy for tuning the electronic and magnetic interaction between the dopant and the TI substrate. Here, depending on the transition metal ion, the ligand field related to the organic molecular structure and the molecular charge, the magnetic moment and anisotropy can be consequently manipulated.

Resumen del póster presentado al CIBERDEM Annual Meeting, celebrado en Cerdanyola del Vallès, Barcelona (España) del 11 al 13 de mayo de 2016.-- et al., Currently, the aetiology of type 1 diabetes mellitus (T1DM) remains unknown and strategies to cure this disease are not available. To prevent and cure T1DM, a sine qua non condition is the arrest of the autoimmune β-cell destruction. An ideal immunotherapy should restore immunological self-tolerance, avoiding systemic side effects and allowing islet regeneration. A physiological strategy to avoid autoimmunity is apoptosis. Apoptotic cells are a source of autoantigens, and when they are phagocytosed, induce tolerance and promote cell replacement. Based on these features, liposomes mimicking apoptotic β-cells have been created as immunotherapy for T1DM. Liposomes are vesicles clinically used for drug delivery and are safe and biocompatible. Liposomes rich in phosphatidylserine (PS), a membrane component exposed during apoptosis and the main signal for phagocytosis, were loaded with β-cell autoantigens. PS-liposomes showed multivesicular morphology and optimal size for phagocytosis. PS-liposome induced tolerogenic dendritic cells (tolDCs), capable of inducing self-tolerance. TolDCs display low levels of costimulatory molecules, secrete prostaglandin E2, a lipid mediator with suppressive function, and impair autoreactive T cell proliferation. The tolerogenic potential of PS-liposomes has been confirmed in non-obese diabetic (NOD) mice, the spontaneous model of T1DM. When administered to prediabetic NOD mice, PS-liposome signal was detected in lymph nodes, spleen and pancreas. Importantly, a single dose of PS-liposomes administered at pre-clinical stage, arrests β-cell destruction, reduces insulitis, and permanently prevents T1D. PS-liposome treatment results in a fast expansion of antigen-specific T cells that could prove to possess regulatory function. Therefore, PS-liposomes mimicking apoptotic β-cells can be an effective antigen-specific immunotherapy, constituting a promising strategy to arrest autoimmunity in T1DM and other autoimmune diseases., Work supported by ISCiii (FIS PI12/00195, PI15/00198). European patent filed.

Resumen del póster presentado a la 10th Conferencia Fuerzas y Túnel, celebrada en Girona (España) del 5 al 7 de septiembre de 2016., Designing functional devices based on organic films require a detailed knowledge of the mechanisms that govern their electronic properties. Therefore, it is of prime importance to understand the close relationship existing between the molecular organization of an organic film and its electronic structure. Additionally, the doping of organic semiconductors by using electron donor species like alkali atoms constitutes an effective strategy to improve the performance of organic optoelectronic devices and fabricating materials with exotic electronic properties, such as organic superconductors. Here, we investigate the influence of chemical doping and molecular organization on the electronic properties of a metal-porphyrin derivative (CoTPPBr) by using low-temperature scanning tunneling microscopy (LT-STM) and spectroscopy (STS) techniques. During this work, we observed that the CoTPPBr molecule forms a square self-assembled structure on the Au(111) substrate, similar to what it is generally observed for metalloporphyrin derivatives. In contrast, new self-assembled networks based on the CoTPPBr molecule were seen on the Ag(111) substrate. Additionally, a covalently bound architecture was formed on both substrates after a thermally activated de-bromination reaction. As a consequence, a shift of the HOMO and LUMO orbitals toward higher energies is observed on the silver substrate but not on the gold. Furthermore, a strong modification of the electronic properties of the metal-organic film upon chemical doping was observed using alkali atoms. After doping, the d-levels suffer a drastic change and according to the STS spectra near the Fermi level this has strong consequences to the magnetic state of the molecule. The results presented here give some insights in the realization of covalent metalorganic networks with desired electronic properties.

Resumen del trabajo presentado al X Congrés de la Societat Catalana d'Inmunologia: "Immunoteràpia contra el Càncer", session III: "From Innate to Adaptative Immunity"; celebrado en Barcelona (España) del 17 al 18 de noviembre de 2016.-- et al., Autoimmune diseases are caused by the destruction of the host’s own cells by autoreactive lymphocytes. There are nearly 100 autoimmune diseases, with increasing incidence and affecting around 5% of the population. Genetic and environmental factors contribute to autoimmunity but the triggering factors remain unknown, and current therapies are poorly effective and cause side effects. Therefore, new and safe approaches are required to arrest autoimmunity and allow target tissue regeneration. Based on apoptotic cells’ ability to induce self-tolerance after phagocytosis, liposomes that possess their inherent tolerogenic features have been designed. Liposomes are phospholipid bilayer vesicles that constitute a versatile system for modulation of immune responses. The herein reported liposomes are made of phosphatidylcholine, cholesterol, phosphatidylserine (PS) —the main 'eat me' signal exposed in the membrane of apoptotic cells—, and display a diameter greater than 500 nm to promote phagocytosis. Liposome’s ability to restore self-tolerance was tested in experimental models of autoimmune diseases: the non-obese diabetic (NOD) mouse for type 1 diabetes (T1D), and the experimental autoimmune encephalomyelitis (EAE)-induced mouse for multiple sclerosis (MS). Liposomes were generated encapsulating disease-specific autoantigens: insulin peptides for T1D and myelin-oligodendrocyte glycoprotein peptide for MS. Liposomes were efficiently engulfed by dendritic cells, inducing a tolerogenic phenotype and function. Liposomes were successful at arresting autoimmunity in vivo: T1D and EAE’s incidence was decreased and their onset delayed. Moreover, EAE’s severity was reduced. PS-Liposomes induced an antigen-specific CD4+ FoxP3+ and FoxP3– T cell response in the T1D model, and FoxP3– T lymphocytes correlated with minor clinical signs and hinted at belonging to Type 1 regulatory T cells in the MS model. This work validates PS-liposomes as a powerful tool for the re-establishment of tolerance. Working synergistically, autoantigen-loaded PS-liposomes co-deliver a double signal of tolerance and specificity to arrest autoimmune reactions in an effective and safe manner.

La miniaturització de materials metal·lorgànics a escala nanomètrica és una estratègia emergent per al desenvolupament de noves nanoestructures d'una gran diversitat composicional, estructural i morfològica. Aquests nous nanomaterials, molts d'ells porosos, poden presentar un ventall variat de propietats i, en conseqüència, poden ser utilitzats en diverses àrees tecnològiques, sigui en l'emmagatzematge o la separació de gasos i catàlisis, sigui per formar nous sensors, nanotransportadors de fàrmacs i agents de contrast. Immersos en el desenvolupament d'aquestes nanoestructures, el nostre grup de recerca està actualment desenvolupant una nova aproximació basada en l'ús de biomolècules com a lligands orgànics que, coordinades amb ions metàl·lics, permetin la creació de nanoarquitectures metal·lobiomoleculars. Aquestes nanoestructures combinaran les propietats dels nanomaterials metal·lorgànics (per exemple, la porositat) amb les propietats intrínseques de les biomolècules, com ara la biocompatibilitat, el reconeixement selectiu o la quiralitat. En aquesta comunicació s'exposaran els últims avanços efectuats en el desenvolupament de noves metodologies sintètiques i el seu ús per sintetitzar les primeres nanoestructures metal·lobiomoleculars formades per aminoàcids com l'àcid aspàrtic (Asp) i la cisteïna (Cys)., The miniaturization of metal-organic materials to the nanoscale is an emerging strategy for the development of new nanostructures with tailored compositions, structures and morphologies. These new nanomaterials, many of which are porous, may have a wide range of properties and consequently show promise for many practical applications, such as gas storage or separation, catalysis, sensors, drug-delivery and contrast agents. With this aim, our research group is currently developing a new approach using biomolecules to coordinate metal ions and create metal-biomolecule nanoarchitectures. These new bioinspired nanostructures will combine the properties of more conventional metal-organic nanomaterials (e. g. porosity) with the intrinsic characteristics of the biomolecules, such as biocompatibility, chirality and selective recognition capabilities. This paper presents the latest advances in the development of new synthesis methodologies and their use in producing the first metal-biomolecule nanostructures based on amino acids, such as aspartic acid (Asp) and cysteine (Cys).

7 páginas, 5 figuras., In this manuscript we demonstrate the spatially controlled immobilization of ferritin proteins by directly writing them on a wide range of substrates of technological interest. Optical and fluorescence microscopy, AFM and TOF-SIMS studies confirm the successful deposition of the protein on those surfaces. Control on nanostructure shape and size, by miniaturizing the dot-like features down to a 100 nm, demonstrates the particular capabilities of the DPN approach. Ultimately, this study gives the opportunity to design nanoparticle-based arrays regarding the growing interest in the use of nanoparticles as structural and functional elements for fabricating nanodevices. Herein, we demonstrate how the protein shell of ferritins can be removed by a simple heat-treatment process while maintaining the encapsulated inorganic nanoparticle intact on the same location of the nanoarray. As a result, this study establishes how direct-write DPN approach could give the opportunity to design not only protein-based nanoarrays but also nanoparticle-based nanoarrays with high-resolution and control., D. M. thanks the Ministerio de Ciencia y Tecnología for a RyC contract. A. L. thanks ARAID for financial support. R. de M. is indebted to MICINN for receiving a predoctoral FPU fellowship.

Fecha de solicitud: 05-11-2009.- Titular: Consejo Superior de Investigaciones Científicas (CSIC), The present invention describes a metallo-organic system that includes: a metal ion salt or complex; at least one organic ligand; and a substance of interest to be encapsulated, belonging to the group comprising a biological entity, a drug, a vaccine, a diagnostic contrast agent, a marker, an organic compound, an inorganic compound, a metallo-organic compound or a nanomaterial or nanodevices. Also described is the method for obtaining same and the uses thereof for the release and/or protection and/or storage of said substances in the pharmaceutical, chemical, environmental, medical and industrial sectors., La presente invención describe un sistema metallo-organic que incluya: una sal del ion metálico o complejo por lo menos un ligand orgánico y una sustancia del interés de ser encapsulado, perteneciendo al grupo comprendiendo una entidad biológica, un fármaco, una vacuna, un agente de contraste del diagnóstico, un marcador, un compuesto orgánico, un compuesto inorgánico, un compuesto metallo-organic o un nanomaterial o nanodevices. También descrito es el método para obtener mismo y los usos de eso para la liberación y/o la protección y/o almacenamiento de las sustancias dichas en el farmacéutico, el producto químico, el ambiental, médico y los sectores industriales.

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.

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.

This work bases on the solid?state study of a chiral ZnII?porphyrin derivative (5,10,15,20?tetra[(4?R,R,R,R)?methyl?2?phenoxy?propanoate, 1) building block and its achiral analogous (2). Here, foreseen the rich molecular recognition of the designed metallo?porphyrins (1 and 2) and tendency to crystallize, we recrystallized both using two sets of solvents (CH2Cl2/CH3OH and CH2Cl2/hexane). As a result, four different crystalline arrangements (1a?b, 2a?b, from 0D to 2D) were successfully achieved. We performed solid state studies for all the species, analysing the role played by chirality, solvent mixtures and surfaces (mica and HOPG), on the supramolecular arrangements. As for the combination of solvents and substrates we obtained a variety of micro?sized species, from vesicles to flower?shaped arrays, including geometrical microcrystals. Overall, our results emphasize the environmental susceptibility of metallo?porphyrins and how this feature must be taken into account in their design.

Here, we report the synthesis of (multi)-layered zeolitic imidazolate framework (ZIF-8/-67) composite particles via a sequential deconstruction–reconstruction process. We show that this process can be applied to construct ZIF-8-on-ZIF-67 composite particles whose cores are the initially etched particles. In addition, we demonstrate that introduction of functional inorganic nanoparticles (INPs) onto the crystal surface of etched particles does not disrupt ZIF particle reconstruction, opening new avenues for designing (multi)-layered ZIF-on-INP-on-ZIF composite particles comprising more than one class of inorganic nanoparticles. In these latter composites, the location of the inorganic nanoparticles inside each single metal–organic framework particle as well as of their separation at the nanoscale (20 nm) is controlled. Preliminary results show that (multi)-layered ZIF-on-INP-on-ZIF composite particles comprising a good sequence of inorganic nanoparticles can potentially catalyze cascade reactions., This work was supported by the EU FP7 ERC-Co 615954, the Spanish MINECO (projects PN MAT2015-65354-C2-1-R, MAT2015-70725-R, and CTQ2016-77989-P), and the Catalan AGAUR (projects 2014 SGR 80, 2014 SGR 612 and 2014 SGR 862). It was also funded by the CERCA Program/Generalitat de Catalunya. N.G.B. acknowledges financial support by MINECO through the Ramon y Cajal program (RYC-2012-10991). ICN2 acknowledges the support of the Spanish MINECO through the Severo Ochoa Centers of Excellence Program under Grant SEV-2013-0295.