Fixation of laccase enzyme into polypyrrole, assisted by chemical interaction with modified magnetite nanoparticles: A facile route to synthesize stable electroactive bionanocomposite catalysts

•Chemically immobilized laccase enzyme on magnetite nanoparticles is presented.•Modified nanoparticles were entrapped in conducting polymer matrix.•Bio-electrocatalytic effect was evidenced in the oxygen reduction reaction.•The method may serve as a general platform for enzyme incorporation.•New avenue for conducting polymer based biocatalytic electrodes.