Determination of Catechol by a Novel Laccase Biosensor Based on Zinc-Oxide Sol-Gel

Abstract

A biosensor was fabricated by incorporating laccase in a ZnO sol-gel with chitosan as a matrix for the determination of catechol. The ZnO nanoparticles were characterized by X-ray diffraction and atomic force microscopy. The conductivity of the chitosan/ZnO/glassy carbon electrode film was investigated by alternating current impedance. The biosensor was employed to monitor the reduction of catechol, and the peak current increased linearly with concentration between 1.0 × 10⁻⁶ and 1.0 × 10⁻⁴ mole per liter with a limit of detection of 2.9 × 10⁻⁷ mole per liter. The laccase biosensor exhibited good stability, reproducibility, and some selectivity.

Keywords:

• Biosensor
• Catechol
• Laccase
• ZnO sol-gel