title: Molecular gated nanoporous anodic alumina for the detection of cocaine.
abstract: 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 × 10-7M 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.
authors.affiliation: Instituto Interuniversitario de Investigaciόn de Reconocimiento Molecular y Desarrollo Tecnolόgico (IDM). Universitat Politècnica de València, Universitat de València, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|CIBER de Bioingeniería, Biomateriales y Nanomedicína (CIBER-BBN).
authors.forename: Àngela
authors.initials: À
authors.lastname: Ribes
authors.affiliation: Departamento de Ingeniería Electrónica, Eléctrica y Automática, Universidad Rovira i Virgili, Avda. Països Catalans 26, 43007, Tarragona, Spain.
authors.forename: Elisabet
authors.initials: E
authors.lastname: Xifré-Pérez
authors.affiliation: Instituto Interuniversitario de Investigaciόn de Reconocimiento Molecular y Desarrollo Tecnolόgico (IDM). Universitat Politècnica de València, Universitat de València, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|CIBER de Bioingeniería, Biomateriales y Nanomedicína (CIBER-BBN).
authors.forename: Elena
authors.initials: E
authors.lastname: Aznar
authors.affiliation: Instituto Interuniversitario de Investigaciόn de Reconocimiento Molecular y Desarrollo Tecnolόgico (IDM). Universitat Politècnica de València, Universitat de València, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|CIBER de Bioingeniería, Biomateriales y Nanomedicína (CIBER-BBN).
authors.forename: Félix
authors.initials: F
authors.lastname: Sancenón
authors.affiliation: Instituto Interuniversitario de Investigaciόn de Reconocimiento Molecular y Desarrollo Tecnolόgico (IDM). Universitat Politècnica de València, Universitat de València, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|CIBER de Bioingeniería, Biomateriales y Nanomedicína (CIBER-BBN).
authors.forename: Teresa
authors.initials: T
authors.lastname: Pardo
authors.affiliation: Departamento de Ingeniería Electrónica, Eléctrica y Automática, Universidad Rovira i Virgili, Avda. Països Catalans 26, 43007, Tarragona, Spain.
authors.forename: Lluís F
authors.initials: LF
authors.lastname: Marsal
authors.affiliation: Instituto Interuniversitario de Investigaciόn de Reconocimiento Molecular y Desarrollo Tecnolόgico (IDM). Universitat Politècnica de València, Universitat de València, Departamento de Química, Universitat Politècnica de València, Camino de Vera s/n, 46022, Valencia, Spain.|CIBER de Bioingeniería, Biomateriales y Nanomedicína (CIBER-BBN).
authors.forename: Ramόn
authors.initials: R
authors.lastname: Martínez-Máñez
mesh_terms: D000537:Aluminum Oxide / Q000737:chemistry*; D015374:Biosensing Techniques; D003042:Cocaine / Q000032:analysis*; D004566:Electrodes; D058608:Nanopores; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D003042:Cocaine; D000537:Aluminum Oxide