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[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. ...

3185 3192 19 4 ; S ; [EN] This paper was published in OPTICS EXPRESS and is made available as an electronic reprint with the permission of OSA. The paper can be found at the following URL on the OSA website: http://dx.doi.org/ 10.1364/OE.19.003185. Systematic or multiple reproduction or distribution to multiple locations via electronic or other means is prohibited and is subject to penalties under law A coupler based on silicon spherical microcavities coupled to silicon waveguides for telecom wavelengths is presented. The light scattered by the microcavity is detected and analyzed as a function of the wavelength. The transmittance signal through the waveguide is strongly attenuated (up to 25 dB) at wavelengths corresponding to the Mie resonances of the microcavity. The coupling between the microcavity and the waveguide is experimentally demonstrated and theoretically modeled with the help of FDTD calculations. © 2011 Optical Society of America. The authors wish to acknowledge financial support from projects FIS2009-07812; Consolider Nanolight.es 2007/0046 and Nº 1841; the Spanish Education and Science Ministry, TEC2008- 06145; the Generalitat Valenciana, project PROMETEO/2008/092 and PROMETEO/2010/043; and project Apoyo a la investigación 2009 from Universidad Politecnica de Valencia, nº reg. 4325. E. Xifré-Pérez acknowledges the financial support from the program Juan de la Cierva (Spanish Ministerio de Educación y Ciencia). J. D. Doménech acknowledges the FPI research grant BES-2009-018381. Finally we thank Prof. J. Garcia de Abajo for providing us with the MESME theoretical program we have used in the calculation of electric field intensity distribution of the Mie modes. Cai, M., Painter, O., Vahala, K. J., & Sercel, P. C. (2000). Fiber-coupled microsphere laser. Optics Letters, 25(19), 1430. doi:10.1364/ol.25.001430 Knight, J. C., Dubreuil, N., Sandoghdar, V., Hare, J., Lefèvre-Seguin, V., Raimond, J. M., & Haroche, S. (1995). Mapping whispering-gallery modes in microspheres with a near-field probe. ...

[EN] A nanoporous anodic alumina (NAA)-based sensor system for the detection of Mycoplasma was developed through the implementation of "molecular gates" selective to the presence of this bacterium. The capped support showed a negligible cargo release, while presence of Mycoplasma genomic DNA resulted in the release of rhodamine B fluorescent dye. This sensor system presents a limit of detection of 20 genomic DNA copies mu L-1 and was applied to the detection of Mycoplasma bacteria in competitive environments, such as culture cell media. ; We thank the Spanish Government (projects MAT2015-64139-C41-R, AGL2015-70235-C2-2-R, and TEC2015-71324-R (MINECO/FEDER, UE)), the Generalitat Valenciana (project PROMETEOII/2014/047), the Catalan authority (project AGAUR 2014SGR1344), and ICREA under the 2014 ICREA Academia Award for support. L.P. thanks to PROMETEOII/2014/047 for his contract. We thank the Electron Microscopy Service at the UPV for support. ; Pla, L.; Xifre Perez, E.; Ribes, À.; Aznar, E.; Marcos Martínez, MD.; Marsal, L.; Martínez-Máñez, R. (2017). A Mycoplasma Genomic DNA Probe using Gated Nanoporous Anodic Alumina. ChemPlusChem. 82(3):337-341. https://doi.org/10.1002/cplu.201600651 ; S ; 337 ; 341 ; 82 ; 3