▎ 摘　　要

The transparency of the gold nanoparticle-graphene-selenocysteine composite is 90-98% in the visible range. The optical and transport energy gaps were estimated as 1.15 eV and 2.25 eV respectively. A new electrochemical method using gold nanoparticle-graphene-selenocysteine modified bismuth film glassy carbon electrode, was applied to improve the performance of the simultaneous determining trace cadmium and lead in square wave anodic stripping voltammetry with a detection limit of 0.08, and 0.05 ppb for metal ions, with a high correlation coefficient of 0.9811 and 0.99, respectively. Finally, the gold nanoparticle-graphene-selenocysteine modified bismuth film glassy carbon electrode was successfully applied for the determination of cadmium, and lead in environmental samples and the results were successful. (C) 2015 The Authors. Published by Elsevier B.V. on behalf of King Saud University. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/).