Rational design of a chromo- and fluorogenic hybrid chemosensor material for the detection of long-chain carboxylates.
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.
Descalzo
Ana B
AB
Centro de Investigación en Química Molecular Aplicada, Departamento de Química, Universidad Politécnica de Valencia, Camino de Vera s/n, E-46071 Valencia, Spain.
Rurack
Knut
K
Weisshoff
Hardy
H
Martínez-Máñez
Ramón
R
Marcos
M Dolores
MD
Amorós
Pedro
P
Hoffmann
Katrin
K
Soto
Juan
J
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
D000838:Anions; D004396:Coloring Agents; D005230:Fatty Acids, Nonesterified; D005456:Fluorescent Dyes; D014867:Water