Amperometric quantification of polar organic solvents based on a tyrosinase biosensor

A novel amperometric biosensor for quantification of the electrochemically inert polar organic solvents based on tyrosinase electrode was preliminaril y reported. The biosensor was fabricated by simply syringing an aqueous sol ution of tyrosinase/PVAVP (PVAVP: copolymer of poly(vinyl alcohol) grafting with 4-vinylpyridine) onto glassy carbon electrode surface followed by dry ing the modified electrode at +4 degrees C in a refrigerator. The current g enerated from electrochemical reduction of quinone is a probe signal. The b iosensor can be used for quantification of polar organic solvents, and its mechanism was characterized with in situ steady-state amperometry-quartz cr ystal microbalance experiments. The detection limit, sensitivity, and dynam ic range for certain organic solvents are dependent on the kind and concent ration of the substrate probe and the hydrophobicity of the immobilization matrix. The response time for all the tested organic solvents is less than 2 min.