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A new simple method for obtaining the intermediate ribbonlike SBA-8 mesoporous silica is presented and discussed. We show how the SBA-8 phase can be prepared with the help of commercial alkyltrimethylammonium nonrigid surfactants (such as cetyltrimethylammonium bromide) instead of rigid bolaform amphiphiles, which were used as templates in the only SBA-8 synthesis procedure previously reported. The method is based on the use of atrane complexes as silicon precursors, and we also show how bringing into play fundamental kinetic parameters (like reaction time and temperature at which the successive reaction steps are carried out) makes it possible to modulate the resulting material topology.

[EN] Gated community: Peptides anchored to the surface of silica mesoporous supports by a valid procedure act as gatekeepers. In this way, "zero release" supports that selectively deliver the cargo in the presence of a suitable peptidase are obtained (see picture, red spheres: cargo, colored chains: peptides). © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim., We thank the Spanish Government (projects MAT2009-14564-C04, CB07/01/2012, and BIO2007 60066), the Generalitat Valencia (project PROMETEO/2009/016, PROMETEO/2010/005), and the CIBER-BBN for their support.

The design of comparatively simple and modularly configurable artificial systems able to communicate through the exchange of chemical messengers is, to the best of our knowledge, an unexplored field. As a proof-of-concept, we present here a family of nanoparticles that have been designed to communicate with one another in a hierarchical manner. The concept involves the use of capped mesoporous silica supports in which the messenger delivered by a first type of gated nanoparticle is used to open a second type of nanoparticle, which delivers another messenger that opens a third group of gated nanoobjects.We believe that the conceptual idea that nanodevices can be designed to communicate with one another may result in novel applications and will boost further advances towards cooperative systems with complex behavior as a result of the communication between simple abiotic individual components., Financial support from the Spanish government (project MAT2012-38429-C04-01) and the Generalitat Valencia (project PROMETEO/2009/016) is gratefully acknowledged. E.A. thanks the Universitat Politecnica de Valencia (project SP20120795) for support. C.G. is grateful to the Spanish Ministry of Science and Innovation for a grant. E.C. is grateful to the Adolf-Martens-Fonds for a fellowship. We are indebted to M. Dinter (LTB Lasertechnik Berlin GmbH) for assistance with the graphics.

A new approach towards the design of "gated scaffolds" based on the combination of capped mesoporous silica nanoparticles (MSNs) with porous biomaterials is reported. Using this approach, a 3D gelatin-based scaffold able to selectively deliver cargo in the presence of an APase enzyme is prepared and tested. This new design opens up the possibility of developing new smart biomaterials with advanced drug-delivery features., The authors thank the Spanish Government (projects MAT2012-38429-C04-01, AGL2012-39597-C02-02, MAT2012-35556, and CSO2010-11384-E), the Generalitat Valenciana (Project PRO-METEO/2009/016) and the CIBER-BBN (BIO-GATES Project) for their support. N. M. also thanks the Spanish Ministry of Science and Innovation for her FPI grant.

We report herein the development of a new optoelectronic nose composed of seven sensing materials prepared by the incorporation of pH indicators and chromogenic reagents selective to metabolites into inorganic materials (UVM-7 and alumina). The nose has been applied to monitor fresh pork sausage ageing. Sausages were packaged together with the disposable array in a modified packaging atmosphere (30% CO2, 70% N2) and colour changes were measured at seven day intervals. Simultaneously, microbiological and sensory analyses were performed. Colour modulations of the chromogenic array were processed with standard analytical tools, including principal component analysis (PCA) and partial least squares (PLS). According to the PCA, the array was able to monitor the sausage spoilage process and to distinguish between each sampled day. Moreover, the PLS statistical analysis of the chromogenic data displayed a linear correlation between the predicted and measured values of the storage days, mesophilic bacteria (cfu g−1) and the sensory score with regression coefficients of 0.9300, 0.9472 and 0.9381, respectively., The financial support from the Spanish Government (projects CIT-060000-2008-14 and MAT2009-14564-004-01), the Generalitat Valenciana (PROMETEO/2009/016) and UPV (PAID 2414) is gratefully acknowledged. Y.S. also thanks the Spanish Ministry of Science for a PhD fellowship.

[EN] Three new hybrid gated mesoporous materials (SN3-1, SNH2-2, and SN3-3) loaded with the dye [Ru(bipy)(3)](2+) (bipy=bipyridine) and capped with different tetrathiafulvalene (TTF) derivatives (having different sizes and shapes and incorporating different numbers of sulfur atoms) have been prepared. The materials SN3-1 and SN3-3 are functionalized on their external surfaces with the TTF derivatives 1 and 3, respectively, which were attached by employing the click chemistry reaction, whereas SNH2-2 incorporates the TTF derivative 2, which was anchored to the solid through an amidation reaction. The final gated materials have been characterized by standard techniques. Suspensions of these solids in acetonitrile showed zero release, most likely because of the formation of dense TTF networks around the pore outlets. The release of the entrapped [Ru(bipy)(3)](2+) dye from SN3-1, SNH2-2, and SN3-3 was studied in the presence of selected explosives (Tetryl, TNT, TNB, DNT, RDX, PETN, PA, and TATP). SNH2-2 showed a fairly selective response to Tetryl, whereas for SN3-1 and SN3-3 dye release was found to occur with Tetryl, TNT, and TNB. The uncapping process in the three materials can be ascribed to the formation of charge-transfer complexes between the electron-donating TTF units and the electron-accepting nitroaromatic explosives. Finally, solids SNH2-2 and SN3-1 have been tested for Tetryl detection in soil with good results, pointing toward a possible use of these or similar hybrid capped materials as probes for the selective chromo-fluorogenic detection of nitroaromatic explosives., Financial support from the Spanish Government (project MAT2012-38429-C04-01) and the Generalitat Valencia (project PROMETEO/2009/016) is gratefully acknowledged. J.O. Jeppesen gratefully acknowledges financial support provided by the EC FP7 ITN "FUNMOLS" Project No. 212942), the Villum Foundation, the Carlsberg Foundation, and the Danish Natural Science Research Council (#11-106744). Y. Salinas thanks the Spanish Ministry of Science and Innovation for her grant. We also thank Stephen Boyer, School of Human Sciences, Science Centre, London Metropolitan University, for carrying out the elemental analyses.

Das Design von vergleichsweise einfachen und modular konfigurierbaren k nstlichen Systemen, die ber den Austausch von chemischen Botenstoffen miteinander kommunizieren kçnnen, ist unseres Wissens ein bislang unerforschtes Gebiet. In einer grundlegenden Arbeit pr sentieren wir hier eine Serie von Nanopartikeln, die in hierarchischer Art und Weise miteinander kommunizieren kçnnen. Das Konzept beruht auf gedeckelten mesoporçsen Silikat-Tr gern, bei denen der aus einem ersten Typ von gesteuerten Nanopartikeln freigesetzte chemische Botenstoff einen zweiten Typ von gedeckelten Nanopartikeln çffnet, welche wiederum einen anderen Botenstoff freisetzen, die eine dritte Gruppe von gesteuerten Nanoobjekten çffnen. Dieses Konzept, das nanoskopische Objekte so aufgebaut werden kçnnen, dass sie miteinander Informationen austauschen, kann unserer Meinung nach zu einer Reihe neuartiger Anwendungen f hren und wird Fortschritte im Bereich kooperativer Systeme mit komplexen Eigenschaften, die auf der Kommunikation einfacher individueller abiotischer Komponenten basieren, befçrdern.

ω-VOPO 4 has been prepared by thermal decomposition of different oxovanadium hydrogen phosphates, namely VO(HPO 4 ) n H 2 O ( n =2( α ), 2(β) and 4) and β-NH 4 (VO 2 )(HPO 4 ). The ω-VOPO 4 phase only remains well crystallised at relatively high temperatures. Its crystal structure has been determined ab initio from X-ray powder diffraction data collected at 475°C. The cell is tetragonal (space group P4 2 /mmc) with a =4.8552(3) A and c =8.4301(6) A. Starting positional parameters were obtained by direct methods, and the structure was refined using Rietveld profile refinement principles. Disorder of two oxygen sublattices is observed. To rationalise some features of the crystal structure of this new phase, a dynamic model is proposed and discussed.

The coordination behaviour of the ditopic receptor of 1-[p-(2,2′:6′,2′′-terpyrid-4′-yl)tolyl]-1,4,8,11-tetraazacyclotetradecane (L1) towards Co2+ in acetonitrile/water (70:30, v/v) has been investigated. At acidic pH values, the L1−H+−Co2+ system shows an oxidation wave at 150 mV vs. SCE, characteristic of Co2+ in a bis(terpyridine) environment. Upon addition of OH−, a reduction in the intensity of the wave at 150 mV is observed and a new oxidation wave appears at 1.30 V. This new wave is close to that found for [Co(cyclam)]2+ under similar working conditions. The electrochemical data thus suggest that there is a pH-controlled translocation of the Co2+ ion from the bis(terpyridine) to the cyclam environment. A similar inference can be made from the results of UV/Vis studies. A thermodynamic characterization of the L1−H+−Co2+ system has also been carried out. Stability constants have been determined in acetonitrile/water (70:30, v/v, containing 0.1 mol dm−3nBu4NClO4 at 25 °C) using potentiometric techniques. The following species were found: [Co(L1)2H4]6+, [Co(L1)2H3]5+, [Co(L1)H]3+, [Co(L1)]2+, and [Co(L1)(OH)]+. The 2:1 ligand-to-metal species [Co(L1)2H4]6+ and [Co(L1)2H3]5+ are assigned to complexes where Co2+ is coordinated by two terpyridine units. The [Co(L1)H]3+, [Co(L1)]2+, and [Co(L1)(OH)]+ species are assigned to complexes where the Co2+ cation is in the cyclam binding domain. The pH-induced Co2+ jumping between coordination sites is discussed in terms of the different basicities of cyclam and terpyridine. Co2+ jumping between coordination sites has also been studied by the sequential acidification of basic mixtures of L1 and Co2+. Under these conditions, the translocation was observed at a different pH value than when an acid-to-basic path was followed. The effect of anions such as phosphate and chloride on the translocation process has also been studied. In the presence of phosphate, translocation occurs at pH = 11 rather than at pH ≈ 8. The phosphate−L1 and phosphate−L1−Co2+ systems have been characterized by potentiometry and a remarkably good agreement has been found between the electrochemical and potentiometric data.

The Cu2+ complex of the ligand L1 (L1 = [Ru(tpycyclam)(mtpy)]2+, tpycyclam = 1-[4′-p-tolyl-(2,2′:6′,2′′-terpyridyl)]-1,4,8,11-tetraazacyclotetradecane and mtpy = 4′-methyl-2,2′:6′,2′′-terpyridine) is able to display a selective sensing response against anions such as ATP. The L1−Cu2+ system contains a Ru(tpy)22+ fluorescent core and a cyclam−Cu2+ subunit. The fluorescent response of the Ru(tpy)22+ core in an aqueous environment (acetonitrile/water, 70:30) is governed by the quenching produced by the Cu2+ cation. In the presence of anions the L1−Cu2+ system shows a rich emission fluorescent response. Electrochemical studies on the Cu(cyclam)2+ complex in propylene carbonate in the presence of certain anions allowed us to conclude that the interaction with the anions sulfate, phosphate, ATP, ADP and GMP is mainly electrostatic whereas chloride and bromide form axial covalent bonds with the copper atom in the Cu(cyclam)2+ complex. The addition of anions that coordinate at the axial positions of the square-planar Cu2+−cyclam subunit (such as Cl−, Br− and OH−) produced an enhancement of the emission intensity. This enhancement is attributed to the occupation of the apical positions of copper in the Cu2+−L1 complex that might reduce the probability of an interaction between the Cu2+ ions and the Ru(tpy)22+ groups reducing the quenching process and, consequently, resulting in an enhancement of the fluorescence. A prediction of the fluorescent behaviour with the anions sulfate, phosphate, ATP, ADP and GMP that give electrostatic interactions with the positively charged cyclam−Cu2+ and/or Ru(tpy)22+ centres is rather difficult. Potentiometric studies on the L1−Cu2+−H+−ATP system suggested that the [Cu(L1)(ATP)] complex is responsible for the quenching observed at basic pH in the presence of ATP. It is noticeable that the quenching of the intensity of the fluorescence due to ATP in the pH range 9 to 10 is selective and no other anion studied is able to quench the emission of the Ru(tpy)22+ core in this pH range.

We describe here for the first time the surfactant-assisted synthesis of thermally stable mesoporous pure TiO 2 having a high surface area. Our synthetic approach to the chemistry of this system is based on the equilibrium between the hydrolysis and condensation reactions of the inorganic species and the organic–inorganic self-assembling processes. The use of titanatrane complexes helps to retard the hydrolysis and condensation reactions, thus allowing us to overcome the difficulties in preparing titanium dioxide mesoporous materials starting from highly reactive Ti-alkoxides. The mesoporous material has been characterized by TEM, XRD and N 2 adsorption–desorption isotherms and displays a typical wormhole-like pore structure.

A new simple and versatile technique to obtain mesoporous oxides is presented. While implying surfactant-assisted formation of mesostructured intermediates, the original chemical contribution of this approach lies in the use of atrane complexes as precursors. Without prejudice to their inherent unstability in aqueous solution, the atranes show a marked inertness towards hydrolysis. Bringing kinetic factors into play, it becomes possible to control the processes involved in the formation of the surfactant–inorganic phase composite micelles, which constitute the elemental building blocks of the mesostructures. Independent of the starting compositional complexity, both the mesostructured intermediates and the final mesoporous materials are chemically homogeneous. The final ordered mesoporous materials are thermally stable and show unimodal porosity, as well as homogeneous microstructure and texture. Examples of materials synthesised on account of the versatility of this new method, including siliceous, non siliceous and mixed oxides, are presented and discussed.

A polyazacycloalkane containing naphthyl groups, 1,4,8,11-tetrakis(naphthylmethyl)-1,4,8,11-tetraazacyclotetradecane (L1), and the azaoxa cycloalkane receptors containing anthracenyl groups, 7,13-bis(anthracenylmethyl)-1,4,10-trioxa-7,13-diazacyclopentadecane (L2) and 10-anthracenylmethyl-1,4,7-trioxa-10-azacyclododecane (L3), have been synthesized and their activity as fluorescent chemosensors studied towards the metal cations Cu2+, Zn2+, Cd2+, Hg2+ and Pb2+ in THF–water (70∶30 v/v, 0.1 mol dm−3 tetrabutylammonium perchlorate, 25 °C) for L1 and 1,4-dioxane–water (70∶30 v/v, 0.1 mol dm−3 potassium nitrate, 25 °C) for L2 and L3. The crystal structure of the complex [Cd(L1)(Cl)][PF6] has been determined by X-ray single crystal procedures. The co-ordination geometry about the cadmium atom is near square pyramidal with the ligand showing a conformation with the four naphthylmethyl groups pointing above the N4 plane. Potentiometric experiments in THF–water for L1 in the presence of Cu2+, Hg2+ and Pb2+ and in 1,4-dioxane–water for L2 in the presence of Cu2+, Zn2+, Cd2+, Hg2+, Pb2+, and L3 with Cd2+ and Pb2+ have also been carried out. All metals form stable complexes with L1, L2 and L3 with stability constants for the formation of the [M(L1)]2+, [M(L2)]2+ and [M(L3)]2+ species in the sequence Pb2+

On the basis of the industrial interest of the oxovanadium phosphate catalysts, current research effort in this field is focused mainly on the development of synthetic strategies directed towards obtaining open-framework materials. There is a growing body of work describing preparations using hydrothermal procedures under a diversity of conditions. A great number of new solids, whose nets range from lamellar arrays to micro- and mesostructured organizations, has been prepared in last years. In this context, the applicability of concepts and procedures from the zeolites chemistry to systems involving transition elements is critically analyzed.

A unified synthetic strategy has allowed us to rationalize the preparative chemistry of the layered oxovanadium phosphates M(VOPO4)2·nH2O. Thus, we have been able to isolate as single phases with reasonable yields both all the previously characterized phosphates and a new solid containing Ba2+ cations as guest species as well as to prepare new related derivatives involving arsenate anions. In order to organize the experimental results, we have used two complementary models: a simple restatement of the partial charge model (PCM), and the valence matching principle (VMP) (derived from the bond valence method). The crystal structure of the new barium lamellar derivative, Ba(VOPO4)2·4H2O, has been solved from X-ray single crystal data. The cell is monoclinic (space group Pn; Z = 1) with a = 6.3860(3) A, b = 12.7796(9) A, c = 6.3870(5) A, and β = 90.172(6)°. Its structure, like it occurs with the other members of the M(VOPO4)2·nH2O family, can be thought of as derived from that of the well-known lamellar soli...

[EN] A new gated nanodevice design able to control cargo delivery using glucose as a trigger and cyclodextrin-modified glucose oxidase as a capping agent is reported., Financial support from the Spanish Government (projects MAT2012-38429-C04-01 and CTQ2011-24355), Generalitat Valenciana (project PROMETEO/2009/016), UPV (project SP20120795) and Ramon y Cajal Programme (to R. V.) is gratefully acknowledged.

The present study reports a novel approach for the chromogenic sensing of CO2 using silica nanoparticles N1 functionalized with amino and thiol moieties. The reaction of CO2 present in air with the hybrid silica nanoparticles controlled the access of a squaraine dye to the surface of nanoparticles, due to formation of carbamates between amino groups and carbon dioxide. This competitive reaction results in a simple chromogenic response to CO2. By using these bifunctionalized nanoparticles CO2 detection was achieved using suspensions of N1 in phosphate buffer or by using N1 directly in contact with air containing CO2. The use of nanoparticles that can be easily functionalized with two or more individual groups that are able to react with dyes and CO2, and the possible use of a wide range of different dyes (for signalling), makes this approach highly appealing and versatile for the design of chromo¿fluorogenic dosimeters for the evaluation of the accumulative exposure to CO2 in different environments, Financial support from the Spanish Government (project MAT2012-38429-C04-01) and the Generalitat Valencia (project PROMETEO/2009/016) is gratefully acknowledged. A. A. thanks the Generalitat Valencia for a Santiago Grisolia fellowship. M. E. M. is grateful to the Spanish Ministerio de Ciencia e Innovacion for an FPU grant.

[EN] A hybrid capped mesoporous material, which was selectively opened in the presence of Tetryl and TNT, has been synthesised and used for the fluorogenic recognition of these nitroaromatic explosives., Financial support from the Spanish Government (project MAT2012-38429-C04-01) and the Generalitat Valencia (project PROMETEO/2009/016) is gratefully acknowledged. Y.S. and E.P. are grateful to the Spanish Ministry of Science and Innovation for their grants. A. A. also thanks the Generalitat Valenciana for his Santiago Grisolia fellowship.

The dumortierite-family structuresM12X2(SeO3)8(OH)6(M= Co2+and Ni2+;X= OH−and F−) have been synthesized. The crystal structures of the hydroxo-derivatives have been refined from X?ray powder diffraction data in the space groupP63mc(Z= 1) witha= 12.887(3) A andc= 4.981(4) A (M= Co2+,X= OH−or F−) anda= 12.704(5) A andc= 4.925(6) A (M= Ni2+,X= OH−or F−). Application of the Partial Charge Transference Model allows the understanding of the selenite derivatives crystal chemistry.

A general synthetic approach to rationalize the solution preparative chemistry of oxovanadium phosphates containing organic species as structural directing agents is presented. Careful attention is payed to the hydrolysis and condensation processes involving the ionic species in solution, and a simple restatement of the partial charge model (PCM) has been used in order to organize the experimental results. The structure of a new V(IV)−Fe(III) bimetallic oxovanadium phosphate, [H3N(CH2)2NH3]2[H3N(CH2)2NH2] [FeIII(H2O)2(VIVO)8(OH)4(HPO4)4(PO4)4]·4H2O, has been determined by X-ray single crystal diffraction methods. This compound crystallizes in the monoclinic system, space group P21/n and the cell dimensions are as follows: a = 14.383(3) A, b = 10.150(2) A, c = 18.355(4) A, and β = 90.39(3)° (Z = 2). The existence of a complex intercrossing channel system, including a very large channel of 18.4 A of diameter (in which both water molecules and ethylenediamine species are located), is the more interesting fe...

Ferrocenecarboxaldehyde reacts with 2-amino-benzoic acid, 2-amino-5-methyl-benzoic acid or 3-amino-2-naphthoic acid to give the corresponding Schiff-base derivatives 2-ferrocenylmethylidenimino-benzoic acid (1), 2-ferrocenylmethylidenimino-5-methyl-benzoic acid (2) and 3-ferrocenylmethylidenimino-2-naphthoic acid (3). 1, 2 and 3 are stable in the solid state but easily hydrolyze in solution. This hydrolysis has been studied kinetically in a methanol-water medium. In order to increase the stability in solution to use these compounds as ligands, the imino group from 1, 2 and 3 was reduced by NaBH4 to give the amino derivatives 2-ferrocenylmethylamino-benzoic acid (4), 2-ferrocenylmethylamino-5-methyl-benzoic acid (5) and 3-ferrocenylmethylamino-2-naphthoic acid (6). 4, 5 and 6 are stable, both in the solid state and in solution, and potential chelating NO donor ligands containing ferrocenyl groups. The protonation of 4–6 and their complex formation with copper(II) have been investigated by potentiometry in dimethyl sulfoxide (dmso)-water (80:20 wt./wt.) mixtures at 25 °C and 0.1 mol dm−3 KClO4. The molecular structure of 5 has been determined by single-crystal X-ray methods. It crystallizes in the triclinic system, space group P 1 , with a = 6.1747(7), b = 9.539(1), c = 13.511(4) A , α = 88.99(1), β = 87.00(1), γ = 82.34(1)°, V = 787.6(3) A 3 and Z = 2 . An unusual feature of the ferrocene-containing ligand 5 in its interaction with nickel(II) ions was found. Cleavage of the CN bond of the secondary amine 5 and molecular rearrangement yields the protonated tertiary amine 2-bis(ferrocenylmethyl)ammonium-5-methyl-benzoic acid perchlorate (7). Compound 7 crystallizes in the monoclinic system, space group P21/c with a = 9.702(9), b = 27.153(17), c = 22.326(6) A , β = 97.39(6)°, V = 5833(12) A 3 and Z = 8 . Typical reversible oxidation waves were found for 4–7 whereas some degree of irreversibility was detected for their parent imines.

Arsenate derivatives of formula Ni12+xH6–2x(AsO4)8(OH)6(1.16⩽x⩽1.33) have been synthesized. The structures of the two extreme compositions (x= 1.16 and x= 1.33) have been refined from X-ray powder diffraction data. Like the other members of this family, these hydroxyarsenates crystallize in the hexagonal P63mc space group (Z= 1) with a= 12.7018(2)A and c= 5.03223(9)A[V= 703.11(3)A3] and reliability factors RF= 4.5%, Rp= 8.6%, Rwp= 11.1% for x= 1.16, and a=12.6953(2)A and c= 5.0311(1)A[V= 702.23(3)A3] and RF= 3.7%, RP= 6.4%, RWP= 8.9% for x= 1.33. Thermal studies have shown that these tubular dumortierite-like solids remain unaltered, or only slightly modified, up to 700 °C.

This article focuses on the study of the release rate in a family of modified silica mesoporous supports. A collection of solids containing ethyl, butyl, hexyl, octyl, decyl, octadecyl, docosyl, and triacontyl groups anchored on the pore outlets of mesoporous MCM-41 has been prepared and characterized. Controlled release from pore voids has been studied through the delivery of the dye complex tris(2,2¿-bipyridyl)ruthenium(II). Delivery rates were found to be dependent on the alkyl chain length anchored on the pore outlets of the mesoporous scaffolding. Moreover, release rates follow a Higuchi diffusion model, and Higuchi constants for the different hybrid solids have been calculated. A decrease of the Higuchi constants was observed as the alkyl chain used to tune the release profile is longer, confirming the effect that the different alkyl chains anchored into the pore mouths exerted on the delivery of the cargo. Furthermore, to better understand the relation between pore outlets decoration and release rate, studies using molecular dynamics simulations employing force-field methods have been carried out. A good agreement between the calculations and the experimental observations was observed., Financial support from the Spanish Government (projects MAT2009-14564-C04-01 and MAT2009-14564-C04-04) and the Generalitat Valencia (project PROMETEO/2009/016) is gratefully acknowledged.

This presentation describes the teaching experience in a course on Sensors Electronics following the criteria of the Erasmus Mundus Masters and applied to International Master in Materials and Sensor Systems for Environmental Technologies given at Universitat Politecnica de Valencia. The main teaching challenge was to provide a course of clearly electronic content to students from any related field, mostly with chemistry and the environment, for this, a program with a large practical component was developed and therefore, electronic modules for measurements with different types of sensors were constructed and applied.

A new optoelectronic nose to monitor chicken meat ageing has been developed. It is based on 16 pigments prepared by the incorporation of different dyes (pH indicators, Lewis acids, hydrogenbonding derivatives, selective probes and natural dyes) into inorganic materials (UVM-7, silica and alumina). The colour changes of the sensor array were characteristic of chicken ageing in a modi¿ed packaging atmosphere (30% CO2¿70% N2). The chromogenic array data were processed with qualitative (PCA) and quantitative (PLS) tools. The PCA statistical analysis showed a high degree of dispersion, with nine dimensions required to explain 95% of variance. Despite this high dimensionality, a tridimensional representation of the three principal components was able to differentiate ageing with 2-day intervals. Moreover, the PLS statistical analysis allows the creation of a model to correlate the chromogenic data with chicken meat ageing. The model offers a PLS prediction model for ageing with values of 0.9937, 0.0389 and 0.994 for the slope, the intercept and the regression coef¿cient, respectively, and is in agreement with the perfect ¿t between the predicted and measured values observed. The results suggest the feasibility of this system to help develop optoelectronic noses that monitor food freshness.

Learning to let go with age: Intracellular controlled release of molecules within senescent cells was achieved using mesoporous silica nanoparticles (MSNs) capped with a galacto-oligosaccharide (GOS) to contain the cargo molecules (magenta spheres; see scheme). The GOS is a substrate of the senescent biomarker, senescence-associated β-galactosidase (SA-β-gal), and releases the cargo upon entry into SA-β-gal expressing cells., We thank the Spanish Government (projects MAT2009-14564-C04 and FIS PI11-0949) the Generalitat Valencia (project PROMETEO/2009/016), and the Universidad Politécnica de Valencia (UPV PAID-05-09) for support. We thank Fundación Ramón Areces for support. C.M.-G. is supported by CIBERER. L.M. thanks the Generalitat Valenciana for her VALI+D postdoctoral contract.

WOS: 000303889500031, PubMed: 22543447, We report here the on-command cargo controlled delivery using an alternating magnetic field (AMF) from magnetic silica mesoporous supports capped with a lipid bilayer., Spanish GovernmentSpanish Government [MAT2009-14564-C04-01, CTQ2008-00690]; Generalitat ValencianaGeneralitat Valenciana [PROMETEO/2009/016]; Spanish Ministry of Education (MEC)Spanish Government [JC2010-0090], Financial support from the Spanish Government (projects MAT2009-14564-C04-01 and CTQ2008-00690) and the Generalitat Valenciana (project PROMETEO/2009/016) is gratefully acknowledged. E. B. thanks the Spanish Ministry of Education (MEC) for his Jose Castillejo fellowship (JC2010-0090).

MCM-41 silica nanoparticles were used as inorganic scaffolding to prepare a nanoscopic-capped hybrid material S1, which was able to release an entrapped cargo in the presence of certain enzymes, whereas in the absence of enzymes, a zero release system was obtained. S1 was prepared by loading nanoparticles with Safranine O dye and was then capped with a gluconamide derivative. In the absence of enzymes, the release of the dye from the aqueous suspensions of S1 was inhibited as a result of the steric hindrance imposed by the bulky gluconamide derivative, the polymerized gluconamide layer and the formation of a dense hydrogen-bonded network around the pore outlets. Upon the addition of amidase and pronase enzymes, delivery of Safranine O dye was observed due to the enzymatic hydrolysis of the amide bond in the anchored gluconamide derivative. S1 nanoparticles were not toxic for cells, as demonstrated by cell viability assays using HeLa and MCF-7 cell lines, and were associated with lysosomes, as shown by confocal microscopy. Finally, the S1¿CPT material loaded with the cytotoxic drug camptothecin and capped with the gluconamide derivative was prepared. The HeLa cells treated with S1¿CPT underwent cell death as a result of material internalization, and of the subsequent cellular enzyme-mediated hydrolysis and aperture of the molecular gate, which induced the release of the camptothecin cargo., We thank the Spanish Government (Project MAT2009-14564-C04 and SAF2010-15512) and the Generalitat Valenciana (Project PROMETEO/2009/016and/2010/005) for support. I. C. thanks the Universitat Politecnica de Valencia for her fellowship. L. M. thanks the Generalitat Valenciana for her post-doctoral VALi+d contract. E. A. and C. T. also thank the CIBER-BBN for contracts. We thank Eva Maria Lafuente Villarreal and Alberto Hernandez Cano from the Confocal Microscopy service of CIPF and the Electronic Microscopy service of UPV for their technical support.

The development of nanoscopic hybrid materials equipped with “molecular gates” showing the ability of releasing target entrapped guests upon the application of an external trigger has attracted great attention and has been extensively explored during recent years.1 These nanodevices are composed of two subunits, namely, a suitable support and certain capping entities grafted on the surface of the scaffolding.2 The support is used as a suitable reservoir in which certain chemicals can be stored whereas the molecules grafted in the outer surface act as a “gate” and can control the release of the entrapped molecules at will. Both components are carefully selected and arranged in order to achieve a wide range of required functionalities.

11 páginas, 7 figuras, 3 tablas y 2 esquemas, The preparation of a new capped silica mesoporous material, Rh-Azo-S, for on-command delivery applications in the presence of target enzymes is described. The material consists of nanometric mesoporous MCM-41-like supports loaded with Rhodamine B and capped with an azopyridine derivative. The material was designed to show “zero delivery” and to display a cargo release in the presence of reductases and esterases, which are usually present in the colon, mainly due to intestinal microflora. The opening and cargo release of Rh-Azo-S in vitro studies were assessed and seen to occur in the presence of these enzymes, whereas no delivery was noted in the presence of pepsine. Moreover, Rh-Azo-S nanoparticles were used to study controlled Rhodamine B dye delivery in intracellular media. HeLa cells were employed for testing the “non”-toxicity of nanoparticles. Moreover, delivery of the dye in these cells, through internalization and enzyme-mediated gate opening, was confirmed by confocal microscopy. Furthermore, the nanoparticles capped with the Azo group and loaded with a cytotoxic camptothecin (CPT) were also prepared (solid CPT-Azo-S) and used as delivery nanodevices in HeLa cells. When this solid was employed, the cell viability decreased significantly due to internalization of the nanoparticles and delivery of the cytotoxic agent., We thank the Spanish Government (projects MAT2009-14564-C04, MAT2012-38429-C04-01, CTQ2007-64735-AR07 and SAF2010-15512) the Generalitat Valenciana (projects PROMETEO/2009/016 and /2010/ 005) for their support. N.M. thanks the Ministerio de Ciencia e Innovaci n for her FPU grant. A.A. and L.M. thank the Generalitat Valenciana for their Santiago Grisolia fellowships and VALI+D postdoctoral contracts.

[EN] An ethylene glycol-capped hybrid material for the controlled release of molecules in the presence of esterase enzyme has been prepared. The final organic-inorganic hybrid solid S1 was synthesized by a two-step procedure. In the first step, the pores of an inorganic MCM-41 support (in the form of nanoparticles) were loaded with [Ru(bipy) 3]Cl 2 complex, and then, in the second step, the pore outlets were functionalized with ester glycol moieties that acted as molecular caps. In the absence of an enzyme, release of the complex from aqueous suspensions of S1 at pH 8.0 is inhibited due to the steric hindrance imposed by the bulky ester glycol moieties. Upon addition of esterase enzyme, delivery of the ruthenium complex was observed due to enzymatic hydrolysis of the ester bond in the anchored ester glycol derivative, inducing the release of oligo(ethylene glycol) fragments. Hydrolysis of the ester bond results in size reduction of the appended group, therefore allowing delivery of the entrapped cargo. The S1 nanoparticles were not toxic for cells, as demonstrated by cell viability assays with HeLa and MCF-7 cell lines, and were found to be associated with lysosomes, as shown by confocal microscopy. However, when S1 nanoparticles were filled with the cytotoxic drug camptothecin (S1-CPT), S1-CPT-treated cells undergo cell death as a result of S1-CPT cell internalization and subsequent cellular enzyme-mediated hydrolysis and aperture of the molecular gate that induced the release of the camptothecin cargo. These findings point to a possible therapeutic application of these nanoparticles. © 2012 American Chemical Society., We thank the Spanish Government (Projects MAT2009-14564-C04 and SAF2010-15512) and the Generalitat Valencia (Project PROMETEO/2009/016) for support. A.A. and L.M. thank the Generalitat Valenciana for their Santiago Grisolia fellowship and VALI+D postdoctoral contract, respectively. We thank Eva Maria Lafuente Villarreal from the confocal microscopy service from CIPF for technical support.

Bi-functionalized hybrid silica nanoparticles have been synthesized, characterized and their optical emission properties in the presence of certain anions studied. The hybrid solid S1, coated with sulforhodamine B as fluorogenic signalling unit and imidazolium groups as anion coordination sites, was prepared by the simultaneous grafting of suitable derivatives of these two subunits on silica nanoparticles. For the preparation of the sensing material S2, first the surface of silica nanoparticles was grafted with (3-aminopropyl)trimethoxysilane yielding solid SN. Then, in a second step, the amino groups on the surface were transformed into the corresponding guanidinium binding sites by reaction with pyrazole carboxamidine yielding solid SG. Finally, the grafting of the sulforhodamine B derivative 1 on SG resulted in the hybrid nanoparticles S2. Acetonitrile suspensions of S1 and S2 showed typical sulforhodamine B absorption bands at ca. 550 nm. Upon excitation, an emission band at 575 nm was observed. Signalling properties of S1 and S2, in acetonitrile and acetonitrile:water 9:1 v/v mixtures, in the presence of organic (acetate, benzoate) and inorganic (F−, Cl−, Br−, CN−, NO3−, HSO4− and H2PO4−) anions were studied. S1 showed a fluorogenic response toward iodide and benzoate, whereas S2 selectively responds to dihydrogen phosphate and hydrogen sulfate., Financial support from the Spanish Government (Project MAT2009-14564-C04-01) and the Generalitat Valenciana (Project PROMETEO/2009/016) is gratefully acknowledged.

A set of nine transition metal oxophosphorous compounds, consisting of four hypophosphites and five phosphites has been synthesized and studied using X-ray powder diffraction techniques. The compounds are α-Mn(H2PO2)2·H2O, Co(H2PO2)2 ·0.53H2O, MCl(H2PO2)2·H2O (M = Co2+, Ni2+), M2(HPO3)2·2H2O (M = Co2+, Ni2+), and M11 (HPO3)8(OH)6 (M = Zn2+, Co2+, Ni2+). Unit cells and X-ray powder patterns are reported.

The synthesis of differently hydrated layered cobalt hypophosphites, Co(H 2 PO 2 ) 2 .nH 2 O (0≤n≤0.69), has been possible by carefully controlling the water content in the reaction medium. The crystal structure of Co(H 2 -PO )2 .0.53H 2 O has been refined from X-ray powder diffraction data by the Rietveld method, using as a starting model the structural parameters of the orthorhombic anhydrous zinc hypophosphite Zn(H 2 PO) 2

We present here a new family of bimodal porous silicas with organically modified surfaces or frameworks constructed from mesoporous primary nanoparticles. These new organosilicas, denoted HPNOs, have been synthesized through a one-pot surfactant-assisted procedure by using a simple commercial template agent in triethanolamine/water media.

Nanosized Ti-UVM-7 materials with a hierarchical system of pores at two different length scales have been prepared through a one-pot procedure by using a simple template agent; the catalytic activity and selectivity of the resulting materials in bulky olefin epoxidation by organic peroxides are the highest reported to date.

The study of probes for CO sensing of a family of binuclear rhodium(II) compounds of general formula [Rh 2{(XC 6H 3)P(XC 6H 4)} n(O 2CR) 4-n]·L 2 containing one or two metalated phosphines (in a head-to-tail arrangement) and different axial ligands has been conducted. Chloroform solutions of these complexes underwent rapid color change, from purple to yellow, when air samples containing CO were bubbled through them. The binuclear rhodium complexes were also adsorbed on silica and used as colorimetric probes for "naked ey" CO detection in the gas phase. When the gray-purple colored silica solids containing the rhodium probes were exposed to air containing increasing concentrations of CO, two colors were observed, in agreement with the formation of two different products. The results are consistent with an axial coordination of the CO molecule in one axial position (pink-orange) or in both (yellow). The crystal structure of 3·(CO) ([Rh 2{(C 6H 4)P(C 6H 5) 2} 2(O 2CCF 3) 2]·CO) was solved by single X-ray diffraction techniques. In all cases, the binuclear rhodium complexes studied showed a high selective response to CO with a remarkable low detection limit. For instance, compound 5· (CH 3CO 2H) 2 ([Rh 2{(m- CH 3C 6H 3)P(m-CH 3C 6H 4) 2} 2(O 2CCH 3) 2]· (CH 3CO 2H) 2) is capable of detection of CO to the "naked ey" at concentrations as low as 0.2 ppm in air. Furthermore, the binding of CO in these rhodium complexes was found to be fully reversible, and release studies of carbon monoxide via thermogravimetric measurements have also been carried out. The importance of the silica support for the maintenance of the CO-displaced L ligands in the vicinity of the probes in a noninnocent manner has been also proved. © 2011 American Chemical Society., The authors wish to express their gratitude to the Spanish Ministerio de Ciencia y e Innovacion (projects MAT2009-14564-C04-01 and CTQ2009-14443-C02-02) and Generalitat Valenciana (project PROMETEO/2009/016) for their support. MEM is grateful to the Spanish Ministerio de Ciencia e Innovacion for an FPU grant.

A hybrid nanoscopic capped mesoporous material, that is selectively opened in the presence of nerve agent simulants, has been prepared and used as a probe for the chromo-fluorogenic detection of these chemicals. © 2011 The Royal Society of Chemistry., Financial support from the Spanish Government (project MAT2009-14564-C04-01 and -02) and Generalitat Valenciana (project PROMETEO/2009/016) is gratefully acknowledged. I. C. thanks the UPV for her Fellowship. SCSIE (Universidad de Valencia) is gratefully acknowledged for all the equipment employed.

The structures of the two new lamellar oxophosphorus compounds of nickel(II), Ni(HPO 3 )-H 2 O (1) and NiCl(H 2 PO 2 ).H 2 O (2), have been determined by X-ray methods. The simple phosphite (I) crystallizcs in an orthorhombic system, space group Pca2 1 (a=8.8982(2) A, b=7.8628(2) A, c=10.0333(3) A, V=701.98(5) A 3 , Z=4), and is isostructural with Co(HPO 3 ).H 2 O. The chlorohypophosphite (2) also crystallizes in an orthorhombic system, space group Pbca

Crystalline microporous phosphites of transition metal ions, have been synthesized through soft hydrothermal treatments. The crystal structures of the cobalt and nickel derivatives have been determined by refinement of X-ray powder diffraction data.

On the basis of the industrial interest of the oxovanadium phosphate catalysts, current research effort in this field is focused mainly on the development of synthetic strategies directed towards obtaining open-framework materials. There is a growing body of work describing preparations using hydrothermal procedures under a diversity of conditions. A great number of new solids, whose nets range from lamellar arrays to micro- and mesostructured organizations, has been prepared in last years. In this context, the applicability of concepts and procedures from the zeolites chemistry to systems involving transition elements is critically analyzed.

The synthesis of new capped silica mesoporous nanoparticles for on-command delivery applications is described. The gate-like functional hybrid systems consisted of nanoscopic MCM-41-based materials functionalized on the pore outlets with different “saccharide” derivatives and a dye contained in the mesopores. A series of hydrolyzed starch products as saccharides were selected. The mesoporous silica nanoparticles S1, S2, and S3 containing the grafted starch derivatives Glucidex 47, Gludicex 39, and Glucidex 29 were synthesized. Additionally, for comparative purposes solid S4 containing lactose was prepared. Delivery studies in pure water in the presence of pancreatin or -D-galactosidase were carried out for S1S3 and S4, respectively. S1, S2, and especially S3 showed very low release in the absence of enzyme, but displayed cargo delivery in the presence of the corresponding enzyme. Moreover, nanoparticles of S1 were used to study the controlled release of the dye in intracellular media. Cell viability assays using HeLa and LLC-PK1 cells indicated that S1 nanoparticles were devoid of unspecific cell toxicity. The endocytosis process for S1 nanoparticle internalization in HeLa cells was confirmed, and the anchored starch was degraded by the lysosomal enzymes. Furthermore, a new mesoporous silica nanoparticle functionalized with Glucidex 47 and loaded with a cytotoxic, S1-DOX, was developed. The cell viability with S1-DOX decreased due to the internalization of the nanoparticle, enzyme-dependent opening of the saccharide molecular gate and the consequent release of the cytotoxic agent. As far as the authors know, this is the first example of enzyme-induced in-cell delivery using capped silica mesoporous nanoparticles., The authors wish to express their gratitude to the Spanish Government (Projects MAT2009 14564 C04 01 MAT2009 14564 C04 04 and BIO2007 60066) and the Generalitat Valencia (Projects PROMETEO/2009/016 and PROMETEO/2010/005) for support A B is grateful to the Universidad Politecnica de Valencia for an FPI grant E A thanks the MICINN for a FPU contract We thank Roquette for the Glucidex samples We would like to thank the CIPF confocal microscopy service for technical support

The fluorescent behaviour of the polyazacycloalkane containing naphthyl groups 1,4,8,11-tetrakis(naphthylmethyl)-1,4,8,11-tetraazacyclotetradecane (L 1 ) and its Cu 2+ complex in the presence of anions are compared in aqueous environment (THF:water 70:30 v/v, 0.1 mol dm −3 tetrabutylammonium perchlorate, 25°C). The emission fluorescent intensity of the L 1 –Cu 2+ system is selectively enhanced in the presence of sulfate at acid pH.

Bis-functionalised silica surfaces have been designed in order to develop selective and sensitive probes for the chromo-fluorogenic detection of certain guests. The designed system consists of a siliceous support bis-functinalised with thiol and polyamine groups. Thiol groups are suitable reactive centres (R) that are know to react with squaraine dyes (D) inducing bleaching, whereas polyamines act as host sites (H) able to coordinate certain target guests (G). In the absence of G, the reactive groups (R) react with the dye resulting in a bleaching of the solution. On the contrary, the presence of certain guest (G) results in a control of the reaction kinetic between R and D and eventually in a complete reaction inhibition. Different functionalised solids were prepared by reaction of the siliceous surface with different concentrations of mercaptopropyltrimethoxysilane (MPTS) and 3-[2-(2-aminoethylamino)ethylamino]propyl-trimethoxysilane (N3TS). The final materials (solids to ) were characterized employing standard procedures. In a first step the reactivity of the signaling dye D (squaraine ) with the reactive centre R (thiol groups) was studied as a function of the pH using solid that showed a most suitable response. At pH 7 and pH 5 there was a quick reaction between the squaraine and the thiol groups on the surface. On the contrary this reaction is significantly slower at pH 3 due to the different degree of protonation of the amines as a function of the pH. Additionally the reaction of with the squaraine has been studied in the presence of a range of inorganic anions with different structural dimensions and charges, including chloride, perchlorate, nitrate, sulfate, phosphate and pyrophosphate. At pH 3 the reaction of the dye with the thiol groups is still effective in the presence of chloride and perchlorate, but the reaction is highly inhibited in the presence of the anions nitrate, sulfate, phosphate and pyrophosphate. At pH 7 the squaraine reacts very fast with the thiol groups in the presence of all the anions studied. In contrast, at pH 5 only pyrophosphate is able to inhibit, to a certain extent, the reaction of the squaraine with the thiols, resulting in a selective chromo-fluorogenic detection of this anion in pure water. Finally, the observed behaviour was discussed in terms of both, the kinetic rates of the reaction between the thiol and the squaraine groups and the thermodynamic interaction reaction between the anions and the polyamine moieties.

We report the development of an MCM-41 mesoporous support that is functionalised with saccharides at the pore outlets and contains the dye [Ru(bipy)(3)](2+) in the pores (solid S1; bipy = 2,2'-bipyridyl). For this hybrid system, the inhibition of mass transport of the dye from the pore voids to the bulk solution in the presence of borate is demonstrated in water at neutral pH. The formation of the corresponding boroester derivative is related to the selective reaction of borate with the appended saccharides. This control is selective and only anion borate, among several anions and cations, can act as a molecular tap and inhibit the delivery of the entrapped guest. Additionally, the S1-borate system behaves as pH-controlled gatelike scaffolding. This pH-responsive release can be achieved in an acidic pH (due to hydrolysis of the boroester), whereas the system remains closed at neutral pH. Molecular dynamic simulations using force-field methods have been made to theoretically study the open/close borate-driven mechanism. A mesoporous silica structure was constructed for this purpose, taking the plane (1-11) of the beta-cristobalite structure as a base on which hexagonal nanopores and anchored saccharide derivatives were included. The final model shows a highly flexible nanopore diameter of approximately 12.5 A of similar size to the [Ru(bipy)(3)](2+) complex (ca. 12 A). However, the anchoring of borate to the appended saccharides results in a remarkable reduction of the pore size (down to ca. 6.4 A) and a significant constraint in the flexibility and mobility of the saccharides. The theoretical calculations are in agreement with the experimental results and enable visualisation of the functional borate-driven dye-delivery-inhibition outcome.

Heparin detective: Silica nanoparticles functionalised with ion-channel scaffolds were prepared and used for the chromofluorogenic sensing of heparin in aqueous environments (see figure). The surface of the nanoparticles was functionalised with polyamines (binding sites) and thiols. The reaction of a dye (squaraine) with the surface thiol groups was selectively inhibited by the coordination of heparin with the partly protonated polyamines.