title: Rational design of a chromo- and fluorogenic hybrid chemosensor material for the detection of long-chain carboxylates.
abstract: A strategy for the rational design of a new optical sensor material for the selective recognition of long-chain carboxylates in water is presented. The approach relies on the combination of structure-property relationships to single out the optimal molecular sensor unit and the tuning of the sensing characteristics of an inorganic support material. A spacer-substituted 7-urea-phenoxazin-3-one was employed as the signaling moiety and a mesoporous trimethylsilylated UVM-7 (MCM-41 type) material served as the solid support. The sensor material shows the advantageous features of both modules that is absorption and emission in the visible spectral range, a fluorescence red-shift and enhancement upon analyte coordination, and the amplification of noncovalent (binding) and hydrogen-bonding (recognition) interactions in the detection event. Besides these basic results that are related to the design and performance of the sensor material, the paper discusses general aspects of amido-substituted phenoxazinone photophysics and addresses some general features of molecular anion recognition chemistry in aqueous vs nonaqueous media, utilizing steady-state and time-resolved optical as well as NMR spectroscopies. Detailed studies on potentially competing biochemical species and a first access to the schematic model of the response of the sensor material as obtained by a combination of fluorescence lifetime distribution analysis and Langmuir-type fitting of the gross binding constants complement the key issues of the paper.
authors.affiliation: Centro de Investigación en Química Molecular Aplicada, Departamento de Química, Universidad Politécnica de Valencia, Camino de Vera s/n, E-46071 Valencia, Spain.
authors.forename: Ana B
authors.initials: AB
authors.lastname: Descalzo
authors.forename: Knut
authors.initials: K
authors.lastname: Rurack
authors.forename: Hardy
authors.initials: H
authors.lastname: Weisshoff
authors.forename: Ramón
authors.initials: R
authors.lastname: Martínez-Máñez
authors.forename: M Dolores
authors.initials: MD
authors.lastname: Marcos
authors.forename: Pedro
authors.initials: P
authors.lastname: Amorós
authors.forename: Katrin
authors.initials: K
authors.lastname: Hoffmann
authors.forename: Juan
authors.initials: J
authors.lastname: Soto
mesh_terms: D000838:Anions; D004396:Coloring Agents / Q000737:chemistry*; D005230:Fatty Acids, Nonesterified / Q000032:analysis*; D005456:Fluorescent Dyes / Q000737:chemistry*; D008958:Models, Molecular; D019906:Nuclear Magnetic Resonance, Biomolecular; D055095:Optics and Photonics; D013050:Spectrometry, Fluorescence; D014867:Water / Q000737:chemistry
chemical_list: D000838:Anions; D004396:Coloring Agents; D005230:Fatty Acids, Nonesterified; D005456:Fluorescent Dyes; D014867:Water