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The use of liquid crystals for the fabrication of displays incorporated in technological devices (TVs, calculators, screens of eBook’s, tablets, watches) demonstrates the relevance that these materials have had in our way of living. However, society evolves, and improved devices are looked for as we create a more efficient and safe technology. In this context, metallomesogens can behave as multifunctional materials because they can combine the fluidic state of the mesophases with properties such as photo and electroluminescence, which offers new exciting possibilities in the field of optoelectronics, energy, environment, and even biomedicine. Herein, it has been established the role of the molecular geometry induced by the metal center in metallomesogens to achieve the self-assembly required in the liquid-crystalline mesophase. Likewise, the effect of the coordination environment in metallomesogens has been further analyzed because of its importance to induce mesomorphism. The structural analysis has been combined with an in-depth discussion of the properties of these materials, including their current and potential future applications. This review will provide a solid background to stimulate the development of novel and attractive metallomesogens that allow designing improved optoelectronic and microelectronic components. Additionally, nanoscience and nanotechnology could be used as a tool to approach the design of nanosystems based on luminescent metallomesogens for use in bioimaging or drug delivery., Associate Laboratory for Green Chemistry—LAQV, FCT/MCTES (Portugal), Projects UIDB/50006/2020, PROTEOMASS Scientific Society (Portugal), Proteomass 2020 funds, Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Porous silica materials make great supports for heterogeneous catalysis with immobilized enzymes; however, direct functionalization of their surface through stable attachment of enzymes, reporter molecules, or both is a difficult problem. Overcoming that is necessary for practical implementation. Here, we integrate the development of luminophor-doped oxygen-sensing silica materials with a modular strategy of enzyme immobilization to demonstrate generally applicable design of an oxygen-dependent biocatalyst on a porous silica support. Zbasic2, a highly positively charged silica-binding module of about 7 kDa size, was fused to d-amino acid oxidase, and the resulting chimeric protein was tethered noncovalently via Zbasic2 in defined orientation and in a highly selective manner on silica. The enzyme supports used differed in overall shape and size as well as in internal pore structure. A confocal laser scanning microscopy (CLSM) analysis that employed the oxidase’s flavin cofactor as the fluorescent reporter group showed a homogeneous internal protein distribution in all supports used. Ru-based organometallic luminophor was adsorbed tightly onto the silica supports, thus enabling internal optical sensing of the O2 available to the enzymatic reaction. Optimization of the surface labeling regarding homogeneous luminophor distribution was guided, and its efficacy was verified by CLSM. Mesostructured silica surpassed controlled pore glass by ≥10-fold in terms of immobilized enzyme effectiveness at high loading of oxidase activity. The effect was shown from detailed comparison of the time-resolved O2 concentration profiles in solution and inside porous support to result exclusively from variable degrees of diffusion-caused limitation in the internal O2 availability. Enzyme immobilized on mesostructured silica approached perfection of a heterogeneous biocatalyst in being almost as effective as the free enzyme (assayed in oxidative deamination of d-methionine), thus emphasizin, Depto. de Ingeniería Química y de Materiales, Fac. de Ciencias Químicas, TRUE, pub

The paddlewheel [Ru2Cl(O2CCH3)4] complex was previously reported to react with the model protein hen egg white lysozyme (HEWL), forming adducts with two diruthenium moieties bound to Asp101 and Asp119 side chains upon the release of one acetate. To study the effect of the equatorial ligands on the reactivity with proteins of diruthenium compounds, X-ray structures of the adducts formed when HEWL reacts with [Ru2Cl(D-p-FPhF)(O2CCH3)3] [D-p-FPhF = N,N′-bis(4-fluorophenyl)formamidinate] under different conditions were solved. [Ru2Cl(D-p-FPhF)(O2CCH3)3] is bonded through their equatorial positions to the Asp side chains. Protein binding occurs cis or trans to D-p-FPhF. Lys or Arg side chains or even main-chain carbonyl groups can coordinate to the diruthenium core at the axial site. Data help to understand the reactivity of paddlewheel diruthenium complexes with proteins, providing useful information for the design of new artificial diruthenium-containing metalloenzymes with potential applications in the fields of catalysis, biomedicine, and biotechnology., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Aza-boron-dipyrromethenes (Aza-BODIPYs) are an increasingly studied class of fluorophores. They can be seen as an azadipyrromethene (“aza-DIPY”) ligand rigidified by a metalloid, a boron atom. Based on this idea, a series of complexes of group 13 metals (aluminum and gallium) have been synthesized and characterized. The impact of the metal and of the nature of the substituents of aza-DIPY core were investigated. The photophysical and electrochemical properties were determined, and an X-ray structure of an azaGaDIPY was obtained. These data reveal that azaGaDIPY and azaAlDIPY exhibit significant red-shifted fluorescence compared to their analogue aza-BODIPY. Their emission can go up to 800 nm for the maximum emission length and up to NIR-II for the emission tail. This, associated with their electrochemical stability (no metal release whether oxidized or reduced) makes them a promising class of fluorophores for optical medical imaging. Moreover, X-ray structure and molecular modeling studies have shown that this redshift seems to be more due to the geometry around the boron/metal than to the nature of the metal., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

Producción Científica, Metal-catalyzed C–H functionalizations on the aryl ring of anilines usually need cumbersome N-protection–deprotection strategies to ensure chemoselectivity. We describe here the Pd-catalyzed direct C–H arylation of unprotected anilines with no competition of the N-arylation product. The ligand [2,2′-bipyridin]-6(1H)-one drives the chemoselectivity by kinetic differentiation in the product-forming step, while playing a cooperating role in the C–H cleavage step. The latter is favored in an anionic intermediate where the NH moiety is deprotonated, driving the regioselectivity of the reaction toward ortho substitution., Ministerio de Ciencia, Innovación y Universidades (projects PID2019-111406GB-I00 and PID-2020-116861GB-I00), Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (projects VA224P20 and VA087-18)

Producción Científica, Metal-catalyzed C–H functionalizations on the aryl ring of anilines usually need cumbersome N-protection–deprotection strategies to ensure chemoselectivity. We describe here the Pd-catalyzed direct C–H arylation of unprotected anilines with no competition of the N-arylation product. The ligand [2,2′-bipyridin]-6(1H)-one drives the chemoselectivity by kinetic differentiation in the product-forming step, while playing a cooperating role in the C–H cleavage step. The latter is favored in an anionic intermediate where the NH moiety is deprotonated, driving the regioselectivity of the reaction toward ortho substitution., Ministerio de Ciencia, Innovación y Universidades (projects PID2019-111406GB-I00 and PID-2020-116861GB-I00), Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (projects VA224P20 and VA087-18)

Producción Científica, Metal-catalyzed C–H functionalizations on the aryl ring of anilines usually need cumbersome N-protection–deprotection strategies to ensure chemoselectivity. We describe here the Pd-catalyzed direct C–H arylation of unprotected anilines with no competition of the N-arylation product. The ligand [2,2′-bipyridin]-6(1H)-one drives the chemoselectivity by kinetic differentiation in the product-forming step, while playing a cooperating role in the C–H cleavage step. The latter is favored in an anionic intermediate where the NH moiety is deprotonated, driving the regioselectivity of the reaction toward ortho substitution., Ministerio de Ciencia, Innovación y Universidades (projects PID2019-111406GB-I00 and PID-2020-116861GB-I00), Junta de Castilla y Leon - Fondo Europeo de Desarrollo Regional (projects VA224P20 and VA087-18)

Two new perovskite compounds, NaLaInNbO6 and NaLaInTaO6, have been synthesized. Both compounds have a rock-salt ordering of the In/Nb or In/Ta cations and a layered ordering of the Na/La. They are unusual among this family of doubly cation ordered perovskites for having a +3/+5 combination of B/B′ oxidation states instead of a divalent cation and W6+. Synchrotron powder diffraction and electron diffraction data show both compounds have tetragonal √2ap × √2ap × 2ap unit cells. The octahedral tilt system of these compounds is complicated and seems to vary depending on the length scale considered. Bond valence considerations demonstrate that none of the tilt systems compatible with a tetragonal unit cell produce a stable structure. It is proposed that additional oxygen displacements are occurring on a local scale. The XRD data show that the B-site ordering is nearly complete in both cases, while the A-site cations show a lower degree of order. The tendency of the B′-cation to undergo a second order Jahn− Teller distortion is identified as having an influence over the degree of A-site ordering. Transmission electron microscopy shows fragmentation into nanosized domains with perpendicular orientations of the layered A-site cation ordering. Such structures may be polar over short length scales which could lead to interesting dielectric properties such as relaxor behavior. The prospects for finding new doubly cation ordered perovskites are also discussed., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

The influence of rare earth (RE) elements on superconducting properties of the transition element (TE)-substituted TExCu1−xSr2RECu2Oy cuprates has not been sufficiently emphasized so far. In the case of molibdocuprates with the general formula Mo0.3Cu0.3Sr2RECu2Oy, all the RE element containing compounds except La, Ce, and Lu can be prepared at room pressure. The influence of the crystal structure on the superconducting properties after ozone oxidation of the present system is reported selecting three groups of RE elements attending to their different atom sizes: small (Yb and Tm), medium (Gd), and big (Nd and Pr). Advanced transmission electron microscopy, various diffraction techniques, and spectroscopic analysis have been used to demonstrate that the increase of structural disorder complemented with a decrease in the hole content play a major role in the vanishing of superconductivity within the present system., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

RESEARCHER ID L-2854-2014 (Rafael Castillo Romero) ORCID 0000-0003-1957-3098 (Rafael Castillo Romero) RESEARCHER ID B-5081-2017 (Daniel Lozano Borregón) ORCID 0000-0001-5902-9201 (Daniel Lozano Borregón) RESEARCHER ID M-3378-2014 (María Vallet Regí) ORCID 0000-0002-6104-4889 (María Vallet Regí), Despite encapsulation of drugs claim to improve the therapeutic profile of free drugs, there are still important limitations in drug delivery. Focusing on cancer treatment, two promising implementations are combination therapy and targeted devices, aimed at increasing the drug effect either by achieving higher cell death rates or by discriminating between cell populations. However, for the time being, the scope of combining both approaches is unknown. To advance this knowledge, there has been designed a two-drug delivery system with dual cell-organelle targeting based on Mesoporous Silica Nanoparticles, known to be able to host drugs within their pores. In vitro results show a synergistic effect and high efficacy, demonstrating that the combination of dual therapy and targeting could still advance the development of drug delivery nanodevices against difficult-to-treat cancers., European Research Council, Ministerio de Economía y Competitividad (MINECO), FONDO EUROPEO DE DESARROLLO REGIONAL (FEDER), Depto. de Química en Ciencias Farmacéuticas, Fac. de Farmacia, TRUE, inpress

Producción Científica, The ligand [2,2′-bipyridin]-6(1H)-one (bipy-6-OH) has a strong accelerating effect on the Pd- catalyzed direct arylation of pyridine or arenes. The isolation of relevant intermediates and the study of their decomposition unequivocally show that the deprotonated coordinated ligand acts as a base and assists the cleavage of the C−H bond. Mechanistic work indicates that the direct arylation of pyridine with this ligand occurs through a Pd(0)/Pd(II) cycle. Because of this dual ligand− intramolecular base role, there is no need for an available coordination site on the metal for an external base, a difficulty encountered when chelating ligands are used in coupling reactions that involve a C−H cleavage step., MINECO (SGPI, grant CTQ2016-80913-P, BES-2014- 067770 fellowship to A.T.), Junta de Castilla y Leoń (grants VA062G18 and VA051P17), Universidad de Valladolid (fellowship to V.S.).

Producción Científica, The ligand [2,2′-bipyridin]-6(1H)-one (bipy-6-OH) has a strong accelerating effect on the Pd- catalyzed direct arylation of pyridine or arenes. The isolation of relevant intermediates and the study of their decomposition unequivocally show that the deprotonated coordinated ligand acts as a base and assists the cleavage of the C−H bond. Mechanistic work indicates that the direct arylation of pyridine with this ligand occurs through a Pd(0)/Pd(II) cycle. Because of this dual ligand− intramolecular base role, there is no need for an available coordination site on the metal for an external base, a difficulty encountered when chelating ligands are used in coupling reactions that involve a C−H cleavage step., MINECO (SGPI, grant CTQ2016-80913-P, BES-2014- 067770 fellowship to A.T.), Junta de Castilla y Leoń (grants VA062G18 and VA051P17), Universidad de Valladolid (fellowship to V.S.).

Producción Científica, The ligand [2,2′-bipyridin]-6(1H)-one (bipy-6-OH) has a strong accelerating effect on the Pd- catalyzed direct arylation of pyridine or arenes. The isolation of relevant intermediates and the study of their decomposition unequivocally show that the deprotonated coordinated ligand acts as a base and assists the cleavage of the C−H bond. Mechanistic work indicates that the direct arylation of pyridine with this ligand occurs through a Pd(0)/Pd(II) cycle. Because of this dual ligand− intramolecular base role, there is no need for an available coordination site on the metal for an external base, a difficulty encountered when chelating ligands are used in coupling reactions that involve a C−H cleavage step., MINECO (SGPI, grant CTQ2016-80913-P, BES-2014- 067770 fellowship to A.T.), Junta de Castilla y Leoń (grants VA062G18 and VA051P17), Universidad de Valladolid (fellowship to V.S.).

Producción Científica, The ligand [2,2′-bipyridin]-6(1H)-one (bipy-6-OH) has a strong accelerating effect on the Pd- catalyzed direct arylation of pyridine or arenes. The isolation of relevant intermediates and the study of their decomposition unequivocally show that the deprotonated coordinated ligand acts as a base and assists the cleavage of the C−H bond. Mechanistic work indicates that the direct arylation of pyridine with this ligand occurs through a Pd(0)/Pd(II) cycle. Because of this dual ligand− intramolecular base role, there is no need for an available coordination site on the metal for an external base, a difficulty encountered when chelating ligands are used in coupling reactions that involve a C−H cleavage step., MINECO (SGPI, grant CTQ2016-80913-P, BES-2014- 067770 fellowship to A.T.), Junta de Castilla y Leoń (grants VA062G18 and VA051P17), Universidad de Valladolid (fellowship to V.S.).

Perovskite-related GdBaMnFeO5 and the corresponding oxidized phase GdBaMnFeO6, with long-range layered-type ordering of the Ba and Gd atoms have been synthesized. Oxidation retains the cation ordering but drives a modulation of the crystal structure associated with the incorporation of the oxygen atoms between the Gd layers. Oxidation of GdBaMnFeO5 increases the oxidation state of Mn from 2+ to 4+, while the oxidation state of Fe remains 3+. Determination of the crystal structure of both GdBaMnFeO5 and GdBaMnFeO6 is carried out at atomic resolution by means of a combination of advanced transmission electron microscopy techniques. Crystal structure refinements from synchrotron X-ray diffraction data support the structural models proposed from the TEM data. The oxidation states of the Mn and Fe atoms are evaluated by means of EELS and Mö ssbauer spectroscopy, which also reveals the different magnetic behavior of these oxides., Depto. de Química Inorgánica, Fac. de Ciencias Químicas, TRUE, pub

RESEARCHER ID K-8193-2014 (Alejandro Baeza) ORCID 0000-0002-9042-8865 (Alejandro Baeza) RESEARCHER ID E-8300-2012 (Eduardo Guisasola Cal) ORCID 0000-0002-2549-1745 (Eduardo Guisasola Cal) RESEARCHER ID M-3378-2014 (María Vallet Regí) ORCID 0000-0002-6104-4889 (María Vallet Regí) RESEARCHER ID L-6167-2014 (Daniel Arcos Navarrete) ORCID 0000-0002-5367-7272 (Daniel Arcos Navarrete), Magnetically triggered drug delivery nanodevices have attracted great attention in nanomedicine, as they can feature as smart carriers releasing their payload at clinician's will. The key principle of these devices is based on the properties of magnetic cores to generate thermal energy in the presence of an alternating magnetic field. Then, the temperature increase triggers the drug release. Despite this potential, the rapid heat dissipation in living tissues is a serious hindrance for their clinical application. It is hypothesized that magnetic cores could act as hot spots, this is, produce enough heat to trigger the release without the necessity to increase the global temperature. Herein, a nanocarrier has been designed to respond when the temperature reaches 43 degrees C. This material has been able to release its payload under an alternating magnetic field without the need of increasing the global temperature of the environment, proving the efficacy of the hot spot mechanism in magnetic-responsive drug delivery devices., Unión Europea. FP7, Ministerio de Economía y Competitividad (MINECO), Agening Network of Excel-82 lence, Fondo Social Europeo (FSE), CIBER, Instituto de Salud Carlos III, Depto. de Química en Ciencias Farmacéuticas, Fac. de Farmacia, TRUE, pub

ORCID 0000-0002-9042-8865 (Alejandro Baeza) RESEARCHER ID K-8193-2014 (Alejandro Baeza) RESEARCHER ID M-3378-2014 (María Vallet Regí) ORCID 0000-0002-6104-4889 (María Vallet Regí), Poor penetration of drug delivery nanocarriers within dense extracellular matrices constitutes one of the main liabilities of current nanomedicines. The conjugation of proteolytic enzymes on the nanoparticle surface constitutes an attractive alternative. However, the scarce resistance of these enzymes against the action of proteases or other aggressive agents present in the bloodstream strongly limits their application. Herein, a novel nanodevice able to transport proteolytic enzymes coated with an engineered pH-responsive polymeric is presented. This degradable coat protects the housed enzymes against proteolytic attack at the same time that it triggers their release under mild acidic conditions, usually present in many tumoral tissues. These enzyme nanocapsules have been attached on the surface of mesoporous silica nanoparticles, as nanocarrier model, showing a significatively higher penetration of the nanopartides within 3D collagen matrices which housed human osteosarcoma cells (HOS). This strategy can improve the therapeutic efficacy of the current nanomedicines, allowing a more homogeneous and deeper distribution of the therapeutic nanosystems in cancerous tissues., Ministerio de Economía y Competitividad (MINECO), Agening Network of Excellence, Depto. de Química en Ciencias Farmacéuticas, Fac. de Farmacia, FALSE, pub

RESEARCHER ID K-3719-2014 (Miguel Manzano García) ORCID 0000-0001-6238-6111 (Miguel Manzano García) RESEARCHER ID M-3378-2014 (María Vallet Regí) ORCID 0000-0002-6104-4889 (María Vallet Regí) RESEARCHER ID G-8740-2015 (María Victoria Cabañas Criado) ORCID 0000-0002-4753-5665 (María Victoria Cabañas Criado), A new ultrasound-responsive system based on mesoporous silica nanoparticles was developed for biomedical applications, grafting a copolymer on their surface that acts as gatekeeper of the pores. The nanoparticles can be loaded with a cargo at low temperature (4 degrees C), taking advantage of the open conformation that the polymer presents under these conditions. Then, at 37 degrees C the copolymer collapses closing the pore entrances and allowing the nanoparticles to carry the drugs at physiological temperature without premature release, which is of great importance when dealing with cytotoxic drugs in cancer treatments. Upon ultrasound irradiation, the sensitive polymer changes its hydrophobicity and, therefore, its conformation toward coil-like opening the gates and releasing the cargo. These hybrid nanoparticles have been shown to be noncytotoxic and can be internalized into LNCaP cells retaining their ultrasound-responsive capability in the cytoplasm of the cells. Moreover, doxorubicin-loaded hybrid MSNs were incubated with LNCaP cells to show their capacity to induce cell death only when the nanoparticles had been exposed to ultrasound. This work demonstrates that our hybrid-MSNs can be triggered by remote stimuli, which is of capital importance for future applications in drug delivery and cancer therapy., Ministerio de Economía y Competitividad (MINECO), CIBER-BBN, VI National RDi Plan, Instituto de Salud Carlos III, Depto. de Química en Ciencias Farmacéuticas, Fac. de Farmacia, TRUE, pub