CYRO-HYDROGEL FOR THE CONSTRUCTION OF A TYROSINASE-BASED BIOSENSOR

A new immobilization method for construction of a tyrosinase based bio sensor is described. A simple physical freezing technique was adopted for preparation. The immobilized enzyme yields specific activities tha t are more than 22% of the soluble enzyme. The enzyme electrode can be stored in dry state for more than three months without any loss of ac tivity. The biosensor was applied to the determination of several phen ols and o-diphenols. The lowest detect limit is 0.02 mu mol/1 and the linear range was 1.0 X 10(-7)-1.0 X 10(-4) mol/1 for catechol. The kin etic parameters have also been calculated.