Electrochemical sensor for simultaneous determination of epinephrine and norepinephrine based on cetyltrimethylammonium bromide assisted SnO2 nanoparticles

highly sensitive and selective electrochemical sensor has been developed for simultaneous determination of catecholamine neurotransmitters, epinephrine (EP) and norepinephrine (NEP) using cetyltrimethylammonium bromide (CTAB) assisted SnO2 nanoparticles (NPs) synthesized by microwave irradiation method. The products were characterized by powder XRD, HRTEM, UV-visible absorption and FTIR spectroscopy and cyclic voltammetric methods. The CTAB-SnO2 NPs modified glassy carbon electrode (GCE) exhibited two sharp well defined reduction peaks for EP and NEP with a significant potential difference of 0.354 V in phosphate buffer solution (pH 5.0). Under optimum conditions, the calibration curves for EP and NEP were obtained over a wide concentration range of 0.1-250 and 0.1-300 mu M with the lowest detection limits of 10 and 6 nM for EP and NEP respectively. Interference studies showed that the modified electrodes have excellent selectivity towards EP and NEP in the presence of potential biological interferents uric acid and ascorbic acid. The proposed electrode has been successfully applied to the simultaneous determination of EP and NEP in human urine samples with satisfactory recoveries.