DITHIOCARBAMATE EXTRACTION AND AU(III) BACK-EXTRACTION FAR DETERMINATION OF MERCURY IN WATER AND BIOLOGICAL SAMPLES BY ANODIC-STRIPPING VOLTAMMETRY

A novel method employed for determining trace mercury in water and bio logical samples was developed in the study. The mercury was preconcent rated from the water samples and the digested biological samples throu gh means of diethyldithiocarbamate extraction in conjunction with AU(3 +) back extraction. The preconcentrated solution, which simply contain ed the enriched mercury ion with the possible transition-metal ions an d nonreacted AU(3+), was next transferred to an electrochemical cell f or detecting mercury via differential pulse anodic stripping voltammet ry (DPASV) through the usage of a gold film carbon electrode. AU(3+) w as selected as a back-extracting agent in light of its standing as hig hest extraction constant with diethyldithiocarbamate, being greater th an that of Hg2+. Besides, the excess nonreacted Au3+ in the preconcent rated solution could be used in situ as the source of generating the g old film of the working electrode in the DPASV. Sufficient evidence of high feasibility in the determination of mercury for different water samples was provided in this present work. Reliability and accuracy of this novel method were confirmed from the NBS biological standard ref erence materials analysis.