An Optode with a Covalently Bound Fluorescent Dye, 3-Acryloylaminobenzanthrone, for an Ethanol Assay

Abstract

The compound 3-acryloylaminobenzanthrone (AABA) has been proposed as a fluorescent carrier for preparing an ethanol-sensitive fiber optode. For immobilizing the fluorescent carrier on a glass surface, copolymerization under UV irradiation was employed after the glass surface was silanized by introducing vinyl groups. A new monomer, 1,2-cyclohexanediol diacrylate (CDDA), was proposed as a cross-linking agent. An optode sensing membrane containing cross-linked AABA, formed after superficial solidification under UV irradiation, was mounted in a flowing system using a plastic-clad fused silica bifurcated fiber-optic bundle. The optode system is well guaranteed to prevent the fluorescent carrier from leaching, and can be utilized for an ethanol assay in a flowing mode. The analytical performance characteristics were evaluated. In an ethanol concentration range of 5 - 90% the fluorescence response obeys the Stern-Volmer equation. A preliminary application of the optode device for determining ethanol in liqueur samples shows the feasibility of using the proposed system in analytical practice.