Determination of cadmium in seawater by cathodic stripping voltammetry of complexes with 5-fluorouracil

A reduction current is obtained when an aqueous solution of cadmium and 5-f luorouracil (5-FU) is subjected to linear sweep cathodic stripping voltamme try. This current is attributed to the reduction of cadmium-5-FU complex io ns which adsorbed onto the hanging mercury drop electrode. The resulting pe ak current is characterized with respect to supporting electrolytes, pH, ac cumulation potential, scan rate, possible interferences and other variables . A linear relationship between the peak current and cadmium concentration was obtained over the range 5 x 10(-9) - 1 x 10(-7) mol dm(-3) with correla tion coefficient of 0.9973. A detection limit of 9.0 x 10(-11) mol dm(-3) w as obtained with standard deviation of 1.9 %. The method was successffuly a pplied for the determination of cadmium in seawater.