Electrochemical fabrication of amperometric glucose enzyme electrode by immobilizing glucose oxidase in electropolymerized poly(3,3'-diaminobenzidine) film on palladinized glassy carbon electrode

A sensitive and stable amperometric glucose enzyme electrode was constructed, based on the immobilization of glucose oxidase in electropolymerized poly(3,3'-diaminobenzidine) film on a palladinized glassy carbon electrode. The electrodeposited porous palladium microparticle matrix provided a greatly enhanced electrode surface area that resulted in a high enzyme loading. The enzyme entrapped in the palladium microparticle matrix exhibited excellent biocatalytic activity and stability. The enzyme electrode provided a linear response to glucose over a concentration range of 1 x 10(-6)-2 x 10(-3) mol dm(-3) and a detection limit of 5 x 10(-7) mol dm(-3). The permselective non-conducting poly(3,3'-diaminobenzidine) film could significantly reduce the interference of other electroactive species and prevented the enzyme electrode from fouling by protein. The electrode was successfully used for the determination of glucose in serum.