Determination of ultra trace of thiosemicarbazide by adsorptive stripping voltammetric method

In the present work, an adsorptive stripping voltammetric method using a hanging mercury drop electrode (HMDE) was described in order to determine the ultra trace of thiosemicarbazide in different real samples. The method is based on accumulation of thiosemicarbazide on mercury electrode. The potential was scanned to the negative direction and the differential pulse stripping voltammograms were recorded. The instrumental and chemical parameters were optimized. The optimized conditions were obtained in pH of 10.0, accumulation potential of 0.00 mV, accumulation time of 60 s, scan rate of 80 mV s-1 and pulse height of 50 mV. The relationship between the peak current versus concentration was linear over the range of 0.50-100.00 ng mL-1. The limits of detection were 0.03 ng mL-1 and the relative standard deviation at 5.00 and 50.00 ng mL-1 of thiosemicarbazide ion were obtained 2.1 and 1.7%, respectively (n = 8).