Abstract The salts of Arsenic (As) are of great toxicological importance and can cause poisoning. The quantitative determination of traces of arsenic and its compounds is important to assess its harmful levels in environmental and biological samples. Therefore quantitative determination of traces of Arsenic in urine is very essential. Routinely, inductively coupled plasma, atomic absorption spectrometry, graphite furnace atomic absorption spectrometry were used for analysis of Arsenic. An attempt has been made to develop for determination of traces of Arsenic in urine using anodic stripping voltammetry. The analysis utilizes three electrode systems, Gold rotating disc electrode (RDE) as a working electrode, Ag/AgCl as a reference electrode and Glassy carbon electrode as an auxillary electrode. Urine was processed by closed digestion method using 34.5% nitric acid (HNO3). Determination of Arsenic was made by primary solution with a sweep rate of 20mV/s and pulse amplitude 50 mV by standard addition method. The solution was purged with nitrogen gas and cleaning was done at -1200 mV for 60 seconds and the potential was scanned from 300 mv to 400 mv on RDE with stirrer speed 2000 rpm. As (III) and As (IV) in HCl were reduced at -1200 mV by nascent hydrogen to As0 and was deposited at 0 mv for 10 sec. The deposited metal was sweeped by scanning the potential from -200 mV to 300 mV using DP mode. The stripping current arising was correlated with the concentration of the metal in the sample. The peak potential for Arsenic is 50 mV. The detection limit of Arsenic by this method was 1.0µg/l.
Keywords: Anodic Stripping Voltammetry (ASV); Gold Rotating Disc Electrode; RDE; Arsenic; Urine; Glassy Carbon Electrode.