Penicillin enzyme biosensors based on pH membrane electrodes

Several penicillin biosensors obtained by covalent binding of penicillinase directly to the surface of pH detectors are presented. Two types of pH electrodes were used: membranes with tridodecylamine, as hydrogen ionophore, incorporated in carboxylated polyvinyl chloride, and membranes made of aminated polyvinyl chloride without any ionophore. Short response time and high stability characterize all described biosensors. The effects of several parameters on the shape of the calibration curves of the biosensors are discussed.