This work reports the voltammetric determination of epinephrine (EP) and xanthine (XA) using gamma irradiated tungsten trioxide (WO3) nanoparticles. WO3 NPs synthesized by anionic surfactant sodium dodecyl sulphate (SDS) assisted template method was subjected to gamma rays under different doses (0150 kGy). The experimental results revealed that the 50 kGy irradiation on SDS-WO3 NPs led to significant changes in crystallite size and morphology which enriched its electrocatalytic activity greatly. The electrochemical behaviors of EP and XA at 50 kGy gamma irradiated SDS-WO3 modified glassy carbon electrodes (GCE) were studied by cyclic voltammetry and differential pulse voltammetry. The outcomes confirmed that the proposed electrode demonstrate excellent electrocatalytic activity towardsthe oxidation of EP and XA in phosphate buffer solution (PBS, pH 7.0). The fabricated electrode possess lowest detection limit of 1.8 nM and 2.2 nM for EP and XA respectively with the very wide dynamic linear range of 9 nM to 1 mM. Finally, the modified sensor was successfully implemented to detect EP and XA in the human serum samples with excellent selectivity, good stability and reproducibility. (C) 2017 Published by Elsevier Ltd.