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Biogenic polyamines, especially spermine and spermidine, are associated with cell growth and development. These amines can be found at high concentrations in the tumor cells, tissues, and urine of cancer patients. In contrast, spermidine levels drop with age, and a possible connection between low endogenous spermidine concentrations and age-related deterioration has been suggested. Thus, the quantification of these amines in body fluids like urine could be used in the diagnosis of different pathological situations. Here a new fluorescent molecular probe based on a tetraphenylethylene derivative is reported. This probe is able to selectively detect these amines through the enhancement of the fluorescence emission of the resulting complex. This fluorescence enhancement may be related to restricted intramolecular rotations of TPE phenyl rings induced by the analyte. Theoretical studies were carried out to shed light on the observed selectivity. Finally, the detection of these amines in urine was performed with limits of detection of 0.70 µM and 1.17 µM for spermine and spermidine, respectively.

[EN] Osteoporosis is an illness which appears when the osteoblast/osteoclast activities are unbalanced taking place bone resorption (caused by osteoclasts) in higher extension than bone formation (induced by osteoblasts). Alendronate is one of the most used drugs for osteoporosis treatment despite its scarce bioavailability. Here we present the synthesis and characterization of mesoporous gated nanoparticles (two sets) for the controlled release of alendronate. The first set of nanoparticles (S1) were loaded with sulforhodamine B and capped with a peptide that could be selectively hydrolyzed by cathepsin K enzyme (overexpressed in osteoclasts). The second set (S2) was functionalized with aminopropyl moieties, loaded with nitrobenzofurazan labelled alendronate and capped with the same peptide. Both nanoparticles were internalized by RAW 264.7 macrophages (which could differentiate in osteoclasts) and were able to release its entrapped cargo in the presence of cathepsin K added in the macrophage lysates. Using S2 nanoparticles 4.2% of the total alendronate amount in contact with the cells is liberated inside them and could produce its therapeutic effect., We thank the Spanish Government (RTI2018-100910-B-C41, RTI2018-100910-B-C42 (MCUI/AEI/FEDER, UE)) and the Generalitat Valenciana (PROMETEU/2018/024) for support. SCSIE (Universitat de Valencia) is gratefully acknowledged for all the equipment employed. NMR was registered at the U26 facility of ICTS "NANBIOSIS" at the Universitat of Valencia.

[EN] Gold nanoparticles functionalized with resorcinol moieties have been prepared and used for detecting formaldehyde both in solution and gas phases. The detection mechanism is based on the color change of the probe upon the aggregation of the nanoparticles induced by the polymerization of the resorcinol moieties in the presence of formaldehyde. A limit of detection of 0.5 ppm in solution has been determined. The probe can be deployed for the detection of formaldehyde emissions from composite wood boards., We thank the Spanish Government (projects MAT2015-64139-C4-4-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support.

[EN] Silica mesoporous microparticles loaded with both rhodamine B fluorophore (S1) or hydrocortisone (S2), and capped with an olsalazine derivative, are prepared and fully characterized. Suspensions of Si and S2 in water at an acidic and a neutral pH show negligible dye/drug release, yet a notable delivery took place when the reducing agent sodium dithionite is added because of hydrolysis of an azo bond in the capping ensemble. Additionally, olsalazine fragmentation induced 5-aminosalicylic acid (5-ASA) release. In vitro digestion models show that S1 and S2 solids are suitable systems to specifically release a pharmaceutical agent in the colon. In vivo pharmacokinetic studies in rats show a preferential rhodamine B release from Si in the colon. Moreover, a model of ulcerative colitis is induced in rats by oral administration of 2,4,6-trinitrobenzenesulfonic acid (TNBS) solutions, which was also used to prove the efficacy of S2 for colitis treatment. The specific delivery of hydrocortisone and 5-ASA from S2 material to the colon tissue in injured rats markedly lowers the colon/body weight ratio and the clinical activity score. Histological studies showed a remarkable reduction in inflammation, as well as an intensive regeneration of the affected tissues., We thank the Generalitat Valenciana (Project PROMETE02018/024) and the Spanish Government (Projects AGL2015-70235-C2-2-R and MAT2015-64139-C4-1-R (MINECO/FEDER)) for support. A.H.T. thanks the Spanish MEC for his FPU fellowship. The authors also thank the support of the Electron Microscopy Service at the UPV. The SCSIE (of the Universitat de Valencia) is also gratefully acknowledged for all the equipment used. NMR spectra were measured at the U26 facility of ICTS "NANBIOSIS" at the Universitat de Valencia.

[EN] Mesoporous silica nanoparticles capped with acetylcholinesterase, through boronic ester linkages, selectively release an entrapped cargo in the presence of acetylcholine., The authors acknowledge financial support from the Spanish Government (MAT2015-64139-C4-1-R, MAT2015-64139-C4-4-R and AGL2015-70235-C2-2-R) and the Generalitat Valenciana (PROMETEO2018/024). T. Godoy-Reyes is grateful to Generalitat Valenciana for her Santiago Grisollía fellowship. A. García-Fernández is grateful to the Spanish Government for her FPU fellowship

[EN] A new environmentally-friendly, simple, selective and sensitive probe for detecting formaldehyde, based on naturally-occurring compounds, through either colorimetric or fluorescence changes, is described. The probe is able to detect formaldehyde in both solution and the gas phase with limits of detection of 0.24 mM and 0.7 ppm, respectively. The probe has been tested to study formaldehyde emission in contaminated real atmospheres. The supported probe is easy to use and to dispose, and is safe and suitable as an individual chemodosimeter., This research was funded by the Spanish Government (projects MAT2015-64139-C4-4-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047).

[EN] Magnetic micro-sized mesoporous silica particles were used for the preparation of a gated material able to release an entrapped cargo in the presence of an azo-reducing agent and, to some extent, at acidic pH. The magnetic mesoporous microparticles were loaded with safranin O and the external surface was functionalized with an azo derivative 1 (bearing a carbamate linkage) yielding solid S1. Aqueous suspensions of S1 at pH 7.4 showed negligible safranin O release due to the presence of the bulky azo derivative attached onto the external surface of the inorganic scaffold. However, in the presence of sodium dithionite (azoreductive agent), a remarkable safranin O delivery was observed. At acidic pH, a certain safranin O release from S1 was also found. The pH-triggered safranin O delivery was ascribed to the acid-induced hydrolysis of the carbamate moiety that linked the bulky azo derivatives onto the mesoporous inorganic magnetic support. The controlled release behavior of S1 was also tested using a model that simulated the gastro intestinal tract., We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. AHT thanks to the Spanish MEC for his FPU grant. The authors also thank the Electron Microscopy Service at the Universitat Politecnica de Valencia for support. SCSIE (Universitat de Valencia) is also gratefully acknowledged for all the equipment employed. NMR was registered at the U26 facility of ICTS "NANBIOSIS" at the Universitat de Valencia. The authors thanks L.A. Villaescusa for his helpful discussion about the 1H-NMR analysis of the composition of loaded and functionalized supports.

[EN] We report a simple, sensitive and selective method for the colorimetric detection of serotonin (5-HT) in aqueous media using bifunctionalized gold nanoparticles (AuNPs). The probe (1) consisted of AuNPs functionalised with dithiobis(succinimidylpropionate) (DSP) and N-acetyl-l-cysteine (NALC). DSP was chosen to react with the amino group of 5-HT, whereas NALC was chosen to bind the hydroxyl group in 5-HT through hydrogen bonding and electrostatic interactions. A double interaction between nanoparticles and the hydroxyl and the amino group of serotonin led to interparticle-crosslinking aggregation. This, resulted in a colour change from red to blue that can be observed by the naked eye. The probe was selective to 5-HT and no colour modulation was observed in the presence of other neurotransmitters (i.e. dopamine, epinephrine, norepinephrine), selected biomolecules (i.e. L-tyrosine, gamma-aminobutyric acid, L-cysteine, uric acid, oxalic acid, aspartic acid and glutamic acid) and common inorganic species. A limit of detection as low as 0.1 mu M was determined in buffered water at pH 7 by UV-vis titrations. Similar response of the probe to 5-HT was observed in simulated blood serum, with a limit of detection of 0.12 mu M, and a linear response within the 0-3 mu M concentration range, which is within the range of the 5-HT concentrations of clinical interest. Finally, the performance of probe (1) in real human blood samples was evaluated, and showed a remarkable ability to distinguish between normal 5-HT levels and 5-HT levels indicative of disease. (c) 2017 Elsevier B.V. All rights reserved., Financial support from the Spanish Government (Projects MAT2015-64139-C4-1-R and MAT2015-64139-C4-4-R) and the Generalitat Valenciana (Project PROMETEOII/2014/047) is gratefully acknowledged. T. Godoy-Reyes is grateful to the Generalitat Valenciana for her Santiago Grisolia fellowship. A. Llopis-Lorente thanks "La Caixa" Banking Foundation for his PhD grant. SCSIE (Universitat de Valencia) is gratefully acknowledged for all the equipment employed. NMR was registered at the U26 facility of ICTS "NANBIOSIS" at the Universitat de Valencia. Support from the Juana Portaceli Health Centre of the Universitat Politecnica de Valencia to obtain blood samples from a healthy volunteer is gratefully acknowledged.

[EN] Two dansyl-modified beta-cyclodextrin derivatives (1 and 2) have been synthesized as host-guest sensory systems for the direct fluorescent detection of the peroxide explosives diacetone diperoxide (DADP) and triacetone triperoxide (TATP) in aqueous media. The sensing is based on the displacement of the dansyl moiety from the cavity of the cyclodextrin by the peroxide guest resulting in a decrease of the intensity of the fluorescence of the dye. Both systems showed similar fluorescent responses and were more sensitive towards TATP than DADP., We thank the Spanish Government (MAT2015-64139-C4-4-R) and Generalitat Valenciana (PROMETEOII/2014/047) for financial support.

A new hybrid material based on sulforhodamine-B dye-loaded silica mesoporous nanoparticles capped with a self-immolative gate has been synthesized and characterized. The gated material's controlled release behavior is monitored under different pH conditions. Under acidic and neutral conditions, a low level of dye release is detected. However, at slightly basic pH, significant dye release occurs owing to deprotonation of the phenol moiety in the capping molecule, which results in its disassembly., We thank MINECO/FEDER (MAT2015-64139-C4-1-R and MAT2015-64139-C4-4-R) and Generalitat Valenciana (PROMETEOII/2014/047) for support. SCSIE (Universidad de Valencia) is gratefully acknowledged for all the equipment employed.

Anew colorimetric and fluorogenic probe,based on a3-formyl boron dipyrromethene (BODIPY)phe-nylhydrazone, for the sensitive and selectivedetectionNO2(g) has been prepared. The probeinsolution experi-ences aremarkablehypsochromic shift of its absorptionand fluorescence emission bands in the presence gaseousNO2(g), leading to limits of detectio noffew ppb. Theprobe also works in the solid phase, adsorbed on filterpaper strips, or chemically immobilized on the surfaceofsilica nanop articles, with limitsofdetection to the nakedeye of about 0.5 ppm., We thank the Spanish Government and FEDER founds (MAT2012-38429-C04) and Generalitat Valenciana (PROME-TEOII/2014/047) for support. SCSIE (Universidad de Valencia) is gratefully acknowledged for all the equipment employed.

[EN] The X-ray crystal structure of a racemic triarylcarbinol derivate ((±)-1) was determined. Compound (±)-1 crystallizes as a chiral structure in the noncentrosymmetric Sohncke space group P21 and the crystals show a special case of enantiomeric disorder with two molecules of opposite handedness sharing many of the atomic positions in the asymmetric unit. The corresponding (R)- and (S)-enantiomers of 1 were separated by chiral HPLC, and crystallized independently yielding single crystals of both of them. The X-ray diffraction analysis of the crystals allowed the determination of the absolute configuration of both enantiomers (R)-1 and (S)-1. Both enantiomers establish intermolecular hydrogen bonds in the solid state, which induce significant differences in their molecular arrangement when compared to racemic crystal (±)-1., We acknowledge the MINECO and European FEDER funds (MAT2012-38429-C04-02 project) and FPU scholarship for financial support. We also want to express our gratitude to ICMOL and University of Valencia for the instrumental used and especially to Prof. Duane Choquesillo-Lazarte and co-workers of the Laboratory for Crystallographic Studies (University of Granada-CSIC) for fruitful discussions.

The crystal structure of two neutral triarylmethane dyes with a p-quinone methide core was determined by X-ray diffraction analysis. The spectroscopic characteristics of both compounds in 23 solvents with different polarities or hydrogen-bonding donor (HBD) abilities has been studied as a function of three solvatochromic parameters (ET(30), π* and α). Both compounds 1 and 2 showed a pronounced bathochromic shift of the main absorption band on increasing solvent polarity and HBD ability. The correlation is better for compound 2 than for compound 1. The stronger effect and better correlation was observed for compound 2 with the increment of the solvent HBD ability (α parameter)., The authors thank the Direccion General de Investigacion Cientifica y Tecnica DGICYT and European Fondo Europeo de Desarrollo Regional FEDER funds (MAT2012-38429-C04-01 and -02) and Generalitat Valenciana (PROMETEOII/2014/047) for support. SCSIE (Universitat de Valencia) is gratefully acknowledged for all the equipment employed.

The molecular geometry of the ionic title compound, C14H17N4+·I−or DAZOP+·I−, is essentially featureless. Regarding the crystal structure, in addition to the obvious cation–anion Coulombic interactions, the packing is mostly directed by non-covalent interactions involving both ring systems, as well as the iodide anion. It consists of cationic molecules aligned along [101] and disposed in an antiparallel fashion while linked into π-bonded dimeric entities by a stacking contact involving symmetry-related phenyl rings, with a centroid–centroid distance of 3.468 (3) Å and a slippage of 0.951 Å. The dimers are, in addition, sustained by a number of C—H...I and I...π (I...centroid = 3.876 Å) interactions involving the anion. Finally, interdimeric contacts are of the C—H...I and C—H...π types.

[EN] Detection and discrimination of several organophosphorus pesticides in water using a colorimetric probe array containing twelve dyes has been achieved. A clear discrimination for malathion, leptophos, dichlorvos, dibrom and diazinon was observed. The array was used to determine the concentration of diazinon in orange leaves, The financial support from the Spanish Government (project MAT2012-38429-C04), the Generalitat Valenciana (project PROM-ETEO/2009/016) and the Universitat Politecnica de Valencia (project ref. 2711) is gratefully acknowledged. SCSIE (Universidad de Valencia) is also acknowledged for all the equipment employed.

The present work aims to give insight into the effect that metal coordination has on the room-temperature conductance of molecular wires. For that purpose, we have designed a family of rigid, highly conductive ligands functionalized with different terminations (acetylthiols, pyridines, and ethynyl groups), in which the conformational changes induced by metal coordination are negligible. The single-molecule conductance features of this series of molecular wires and their corresponding Cu(I) complexes have been measured in break-junction setups at room temperature. Experimental and theoretical data show that no matter the anchoring group, in all cases metal coordination leads to a shift toward lower energies of the ligand energy levels and a reduction of the HOMO−LUMO gap. However, electron-transport measurements carried out at room temperature revealed a variable metal coordination effect depending on the anchoring group: upon metal coordination, the molecular conductance of thiol and ethynyl derivatives decreased, whereas that of pyridine derivatives increased. These differences reside on the molecular levels implied in the conduction. According to quantum-mechanical calculations based on density functional theory methods, the ligand frontier orbital lying closer to the Fermi energy of the leads differs depending on the anchoring group. Thereby, the effect of metal coordination on molecular conductance observed for each anchoring could be explained in terms of the different energy alignments of the molecular orbitals within the gold Fermi level.

Two triphenylmethane based chemodosimeters for selective and chromogenic sensing of cyanide anions in aqueous environments and of hydrogen cyanide in gas phase were prepared and studied., We thank the Spanish Government (project MAT2012-38429-C04-02) for its financial support. R.G. acknowledges Spanish MICINN for a predoctoral fellowship. SCSIE (Universidad de Valencia) is gratefully acknowledged for all the equipment employed.