Poly(amphiphilic pyrrole)-tyrosinase-peroxidase electrode for amplified flow injection-amperometric detection of phenol

A new approach to enhance the sensitivity of a tyrosinase based biosensor for the amperometric phenol detection at − 0.2 V vs. Ag/AgCl (0.1 M KCl) has been described. The procedure consists of the cooperative functioning of tyrosinase and horseradish peroxidase in the presence of H2O2. Monoenzyme and bienzyme electrodes were elaborated by electrochemical polymerisation of amphiphilic pyrrole-enzyme(s) mixtures previously adsorbed on the electrode surface. Batch and flow injection measurements carried out with these biosensors, show that an amplification phenomenon occurs in the presence of H2O2. The role of peroxidase and tyrosinase in the amplification effect has been studied.