Determination of Cadmium in Seawater by Cathodic Stripping Voltammetry of Complexes with 5-Fluorouracil

Abstract

A reduction current is obtained when an aqueous solution of cadmium and 5-fluorouracil (5-FU) is subjected to linear sweep cathodic stripping voltammetry. This current is attributed to the reduction of cadmium-5-FU complex ions which adsorbed onto the hanging mercury drop electrode. The resulting peak current is characterized with respect to supporting electrolytes, pH, accumulation potential, scan rate, possible interferences and other variables. A linear relationship between the peak current and cadmium concentration was obtained over the range 5 × 10−9–1 × 10−7 mol dm−3 with correlation coefficient of 0.9973. A detection limit of 9.0 × 10−11 mol dm−3 was obtained with standard deviation of 1.9 %. The method was successffuly applied for the determination of cadmium in seawater.