A simple and efficient cyclic square wave voltammetric method for simultaneous determination of epinephrine and norepinephrine using an activated pencil graphite electrode

•Epinephrine (EP) and norepinephrine (NP) electrochemical discrimination.•Cost-effective, disposable electroactivated pencil graphite electrode (PGE*).•Developed and validated method based on cyclic square wave voltammetry (CSWV).•Sensitive, simple, reliable individual and/or simultaneous EP and NP determination.•Selective and affordable tool for rapid pharmaceutical samples analysis. Simultaneous determination of catecholamine neurotransmitters epinephrine (EP) and norepinephrine (NP) using an electrochemically activated pencil graphite electrode (PGE*) is reported. Response characteristics of the PGE* toward the mentioned compounds were investigated by cyclic square wave voltammetry. In a mixture of analytes the peak currents of EP and NP increased with concentrations between 2.5 × 10−6 and 2.5 × 10−4 M. Detection limits of 8.32 × 10−7 M for EP and 9.92 × 10−7 M for NP were attained. The method was applied for their quantification in pharmaceutical and human plasma samples.