Simultaneous Determination of Lead and Cadmium in Urine by Oscilloscopic Polarography

An oscilloscopic polarography method for simultaneous determination of Pb(Ⅱ) and Cd(Ⅱ) in urine was studied in this paper.The optimal composition of the supporting electrolytes was selected with orthogonal trial.Under conditions of the optimal composition of supporting electrolytes of potassium iodide-ascorbic acid-hydrochloric acid-phosphoric acid,Pb(Ⅱ) and Cd(Ⅱ) were determined and the linear relationship between peak current and concentration was observed in range of 100 μg·L-1 for both Pb(Ⅱ) and Cd(Ⅱ).RSD′s of the determination were 6.91% for Pb(Ⅱ) and 6.45% for Cd(Ⅱ).DL (3S/N) was 2.0 μg·L-1 for Pb(Ⅱ) and 1.0 μg·L-1 for Cd(Ⅱ).Recovery was in range of 88.4%-101.4% for Pb(Ⅱ) and 83.1%-103.5% for Cd(Ⅱ).