Growth of polypyrrole-horse radish peroxidase microstructures for H2O2 biosensor

Conducting polymer microstructures for enzymatic biosensors are developed by a facile electrochemical route. Horse radish peroxide entrapped polypyrrole films with bowl shaped microstructures are developed on stainless steel (SS 304) substrates by a single step process. Potentiodynamic scanning/cyclic voltammetry is used for generation of polypyrrole microstructures using electro generated oxygen bubbles stabilized by zwitterionic surfactant/buffer N-2-Hydroxyethyl piperazine N-2-ethane sulfonic acid (HEPES) as soft templates. Scanning electron microscopic images reveal the bowl shaped structures surrounded by cauliflower like fractal polypyrrole films and globular nanostructures. Raman spectroscopy reveals the oxidized nature of the film. Amperometric biosensor responses are good with sensitivity of 1.1μA/(cm².mM) in 0-10 mM H₂O₂ concentration range at -0.15 V.