Amperometric Quantification of Polar Organic Solvents Based on a Tyrosinase Biosensor

摘要

A novel amperometric biosensor for quantification of the electrochemically inert polar organic solvents based on tyrosinase electrode was preliminarily reported. The bia-sensor was fabricated by simply syringing an aqueous solution of tyrosinase/PVAVP (PVAVP: copolymer of poly(vinyl alcohol) grafting with 4-vinylpyridine) onto glassy carbon electrode surface foliowed by drying the modified electrode at +4 0C in a refrigerator. The current generated from electrochemical reduction of quinone is a probe signal. The biosensor can be used for quantifica-tion of polar organic solvents, and its mechanism was characterized with in situ steady-state amperometry— quartz crystal microbalance experiments. The detection limit, sensitivity, and dynamic range for certain organic solvents are dependent on the kind and concentration of the substrate probe and the hydrophobicity of the im-mobilization matrix. The response time for all the tested organic solvents is less than 2 min.