Use of rotating Au-thin film electrode for the differential pulse voltammetric study of Hg2+ complexation

A modification of a previously reported electrochemical method [E. Chekmeneva, J.M. Díaz-Cruz, C. Ariño, M. Esteban, J. Electroanal. Chem. 629 (2009) 169–179] to study Hg2+ binding by differential pulse voltammetry (DPV) is described. The modification lies on the change of the rotating Au-disk electrode (Au-RDE) by the rotating Au-thin film electrode (Au-TFE). The experimental procedures for preparation of rotating Au-TFE are optimized. The complexation of Hg2+ with DTPA was investigated by the optimized method in different buffer media. The main advantage of Au-TFE, respect to Au-RDE, is the gain of time in the electrode preparation for the measurements and the absence of the irreversible contamination of the electrode with Hg2+.