Silica nanoparticles with covalently attached fluorophore as selective analyte-responsive supramolecular chemoreceptors

Abstract

Silica core-shell nanoparticles with SiO2 cores and an alkoxysilyl derivative of dibenzoylmethanatoboron difluoride (A-DBMBF2) fluorophore covalently attached to the core surface have been synthesized. It is shown that these nanoparticles can be used as the basis of selective sensor materials capable of detecting benzene, toluene, and xylene vapors. As benzene or its methyl derivatives are adsorbed on the surface of nanoparticles, a quenching of A-DBMBF2 fluorescence occurs while an A-DBMBF2/analyte exciplex fluorescence buildup emerges. The position of isoemissive points in the fluorescence spectra is specific for each analyte and can be used for its identification.