Electropolymerization of graphene and 5-[o-(4-bromine amyloxy) phenyl] -10,15,20-triphenylporphrin (o-BrPETPP) composite film electrode for the electrocatalytic oxidation of indirubin

► The graphene and o-BrPETPP composite film electrode is prepared through a consecutive cyclic voltammetry process. ► The electrocatalytic oxidation of indirubin at the film electrode is investigated. ► The GR-o-BrPETPP film electrode shows a comparative sensitivity with HPLC to the DPV determination of indirubin.