Electrochemical determination of chromium(VI) using metallic nanoparticle-modified carbon screen-printed electrodes.

Carbon screen-printed electrodes (CSPEs) modified with metal nanoparticles present an interesting alternative in the determination of chromium(VI) by differential pulse voltammetry (DPV). Metallic silver and gold nanoparticle deposits have been obtained by electrochemical deposition. Scanning electron microscopy measurements show that the electrochemically synthesized silver and gold nanoparticles are deposited in aggregated form. The detection limit for the analytical procedures developed in this work were 8.5 x 10(-7) and 4.0 x 10(-7)M for silver and gold nanoparticle-modified CSPE, respectively. In terms of reproducibility, the precision of the above-mentioned method was calculated at 6.7% in %R.S.D. values for silver and 3.21% for gold nanoparticle CSPE.