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This document is the Accepted Manuscript version of a Published Work that appeared in final form in Langmuir, copyright © American Chemical Society after peer review and technical editing by the publisher. To access the final edited and published work see http://dx.doi.org/10.1021/acs.langmuir.6b01715. ; Mesoporous silica nanoparticles (MSNs) are highly attractive as supports in the design of controlled delivery systems that can act as containers for the encapsulation of therapeutic agents, overcoming common issues such as poor water solubility and poor stability of some drugs and also enhancing their bioavailability. In this context, we describe herein the development of polyglutamic acid (PGA)-capped MSNs that can selectively deliver rhodamine B and doxorubicin. PGA-capped MSNs remain closed in an aqueous environment, yet they are able to deliver the cargo in the presence of pronase because of the hydrolysis of the peptide bonds in PGA. The prepared solids released less than 20% of the cargo in 1 day in water, whereas they were able to reach 90% of the maximum release of the entrapped guest in ca. 5 h in the presence of pronase. Studies of the PGA-capped nanoparticles with SK-BR-3 breast cancer cells were also undertaken. Rhodamine-loaded nanoparticles were not toxic, whereas doxorubicin-loaded nanoparticles were able to efficiently kill more than 90% of the cancer cells at a concentration of 100 μg/mL. ; A.T. wishes to express her gratitude to the Erasmus mundus (Svagata.eu) financial support. A.U. and C. de la T. are grateful to the Spanish Ministry of Education, Culture and Sport for her doctoral fellowship. We thank the Spanish Government (Project MAT2015-64139-C4-1-R, MINECO/FEDER) and Generalitat Valenciana (Project PROMETEOII/2014/047) for their support. The authors also thank UPV electron microscopy services for the technical support. ; Tukappa, A.; Ultimo, A.; De La Torre Paredes, C.; Pardo Vicente, MT.; Sancenón Galarza, F.; Martínez-Máñez, R. (2016). Polyglutamic Acid-Gated Mesoporous Silica ...

[EN] We present herein the use of nanoporous anodic alumina (NAA) as a suitable support to implement molecular gates for sensing applications. In our design, a NAA support is loaded with a fluorescent reporter (rhodamine B) and functionalized with a short single-stranded DNA. Then pores are blocked by the subsequent hybridisation of a specific cocaine aptamer. The response of the gated material was studied in aqueous solution. In a typical experiment, the support was immersed in hybridisation buffer solution in the absence or presence of cocaine. At certain times, the release of rhodamine B from pore voids was measured by fluorescence spectroscopy. The capped NAA support showed poor cargo delivery, but presence of cocaine in the solution selectively induced rhodamine B release. By this simple procedure a limit of detection as low as 5 × 10−7 M was calculated for cocaine. The gated NAA was successfully applied to detect cocaine in saliva samples and the possible re-use of the nanostructures was assessed. Based on these results, we believe that NAA could be a suitable support to prepare optical gated probes with a synergic combination of the favourable features of selected gated sensing systems and NAA. ; We thank Projects MAT2015-64139-C4-1-R and TEC2015-71324-R (MINECO/FEDER), the Catalan Government (Project 2014 SGR 1344), the ICREA (ICREA2014 Academia Award) and the Generalitat Valenciana (Project PROMETEOII/2014/047) for support. We also thank to the Agencia Espanola del Medicamento y Productos Sanitarios for its concessions. A.R. thanks the UPV for her predoctoral fellowship. The authors also thank the Electron Microscopy Service at UPV for support. ; Ribes, À.; Xifre Perez, E.; Aznar, E.; Sancenón Galarza, F.; Pardo Vicente, MT.; Marsal, LF.; Martínez-Máñez, R. (2016). Molecular gated nanoporous anodic alumina for the detection of cocaine. Scientific Reports. 6. https://doi.org/10.1038/srep38649 ; S ; 38649 ; 6 ; Nadrah, P., Planinšek, O. & Gaberšček, M. Stimulus-responsive Mesoporous Silica Particles. ...

[EN] Aptamers have been used as recognition elements for several molecules due to their great affinity and selectivity. Additionally, mesoporous nanomaterials have demonstrated great potential in sensing applications. Based on these concepts, we report herein the use of two aptamer¿capped mesoporous silica materials for the selective detection of ochratoxin¿A (OTA). A specific aptamer for OTA was used to block the pores of rhodamine¿B¿loaded mesoporous silica nanoparticles. Two solids were prepared in which the aptamer capped the porous scaffolds by using a covalent or electrostatic approach. Whereas the prepared materials remained capped in water, dye delivery was selectively observed in the presence of OTA. The protocol showed excellent analytical performance in terms of sensitivity (limit of detection: 0.5¿0.05¿nm), reproducibility, and selectivity. Moreover, the aptasensors were tested for OTA detection in commercial foodstuff matrices, which demonstrated their potential applicability in real samples ; We thank the Spanish Government (projects MAT2015-64139-C4-1-R and AGL2015-70235-C2-2-R (MINECO/FEDER)) and the Generalitat Valenciana (project PROMETEOII/2014/047) for support. A.R. thanks UPV for her predoctoral fellowship. S.S. thanks the Instituto de Salud Carlos III and the European Social Fund for the financial support "Sara Borrell" (CD16/000237). A.B. thanks the Spanish Government for financial support by the "Juan de la Cierva-Incorporacion" (IJCI-2014-21534). The authors also thank the Electron Microscopy Service at UPV for support. ; Ribes, À.; Santiago Felipe, S.; Bernardos Bau, A.; Marcos Martínez, MD.; Pardo Vicente, MT.; Sancenón Galarza, F.; Martínez-Máñez, R. (2017). Two New Fluorogenic Aptasensors Based on Capped Mesoporous Silica Nanoparticles to Detect Ochratoxin A. ChemistryOpen. 6(5):653-659. https://doi.org/10.1002/open.201700106 ; S ; 653 ; 659 ; 6 ; 5

257 263 191 ; S ; The design, fabrication and validation of an optoelectronic sensor implemented in an easy-to-use portable device for the selective and sensitive detection of CO in air is reported herein. The system is based on the colour changes observed in the binuclear rhodium complex of formula [Rh2[(C6H4)P(C6H5)2]2(O2CCF3)2](CF3CO2H)2(1) upon coordinating CO molecules in axial positions. Complex 1 is used supported on cellulose chromatography paper. In this support, colour changes to the naked eye are observed for CO concentrations above 50 ppm. The probe is also implemented in a simple portable optoelectronic device.The cellulose support containing probe 1 in this device is placed inside a small dark chamber, is illuminated with a tricolour LED emitting at 624, 525 and 470 nm, respectively corresponding to red (R), green (G) and blue (B) light, and reflected light is detected by a photodiode. With a transimpedance amplifier, the current generated by the photodiode is transformed into a voltage compatible with the 10-bit analogue-to-digital converter (ADC) port. Colour changes are measured as the distance d between the R, G and B data of the blank (probe without CO) and that for a certain CO concentration. Typical calibration curves are fitted using a bi-exponential equation. This system offers a typical response time of a few minutes (ca. 7 min) and a limit of detection of 11 ppm. The probe in the cellulose supports is also highly reversible.The optoelectronic device is portable (dimensions 14 × 8.5 × 3.5 cm; weighs approximately 270 g) and is powered by AA batteries. In addition, no variations in experimental parameter d upon exposure to CO2, N2, O2, Ar, water-saturated air and vapours of chloroform, hexane, ethanol, acetone, methane, toluene or formaldehyde are observed. Besides, colour changes are found for acetonitrile vapour, NO and NO2, but only at high concentrations. For validation purposes, the device was used to determine the CO present in the 4-shed accumulated smoke of two cigarette types ...