Graphene nanosheets modified glassy carbon electrode for simultaneous detection of heroine, morphine and noscapine

► Glassy carbon electrode modified with graphene nanosheets (GC/GNSs). ► GC/GNSs was used for electrocatalytic oxidation of morphine, noscapine and heroin. ► DPV technique was used for determination of three important opiate drugs. ► Heroin, noscapine and morphine determined simultaneously or individually. ► Micromolar of these compounds analyzed without any separation or pretreatment steps.