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Abstract The use of differential pulse anodic stripping voltammetry (DPASV) for the determination of a variety of cations 1 Determination of Bi3+At Gold Rotatory Disc Electrode:Differential pulse anodic stripping voltammetry of 10 ppb Bi3+in 0.1M HCl Calibration graphs were obtained from plots of ip vs. Bi3+ concentration which manifested well straight line correlation. The effect of interference of foreign ions was also examined. Anions as NO3,SO42,ClO4 and PO43showed no interference with Bi3+ determination, while with Cl a shift in Ep was noticed. Pb2+ also do not interfere while Cu2+ even at low concentrations cause marked decrease in Ep and ip of Bi3+.Same studies were carried out for Hg2+ and As3+. 2 Determination of Zn2+ at HMDE : The effect of Edep. and tdep. on the anodic stripping voltammograms of 30 ppb of Zn2+ were studied in 0.1 M HCl, acetate buffer (pH=4.7), citrate buffer(pH=3) and tartarate buffer(pH=9.2). Plots of ip vs. tdep. showed fair straight line correlation with some deviation from linearity at the highest tdep. records. Calibration graphs were established from the ip vs. Zn2+ concentration at different tdep in the four base electrolytes where almost well straight lines passing by the point of origin were obtained. Same studies were carried out for Cu2+ ,Pb2+ and Cd2+. The stripping voltammograms of a solution mixture containing equimolar concentrations of Zn2+,Pb2+, Cd2+and Cu2+ were scanned in acetate buffer (pH=4.7) Calibration graphs were obtained by plotting ip values vs. each cation concentration where well straight lines passing by the point of origin were obtained. The results reflect the high fidelity and uniqueness of using the HMDE for analyzing mixture of ions with sufficient precision at ppb concentration limit.The use of ASV technique for heavy metal determination in biological samples was tested through analyzing the liver of experimental mice animals.Determination of Zn2+,Pb2+, Cd2+and Cu2+ was then carried out by atomic absorption spectroscopy and ASV. |