Adsorptive stripping voltammetric determination of the antidepressant drug sulpiride

The electrochemical behaviour of the antidepressant drug sulpiride (SP) at a hanging mercury drop electrode (HMDE) is investigated. Linear sweep cathodic stripping voltammetry (LSCSV) was used to determine sulpiride in the presence of 0.01 M sodium acetate medium pH 10.5 and 25 +/- 1 degrees C. Different parameters such as, supporting electrolyte, pH, accumulation potential, scan rate, accumulation time and ionic strength, were tested to optimize the conditions for the determination of SP. The adsorbed form is reduced irreversibly. The linear concentration range is from 2x10(-9) to 5x10(-8) M SP. Experimentally, 2x10(-9) M (0.68 ppb) with accumulation time 60 s can be determined successfully. Furthermore, a theoretical detection limit of 2 x 10(-10) M (0.068 ppb) Sp was calculated. The interferences of some metal ions, ascorbic acid and some amino acids were studied. The method was applied to the analysis of tablets and spiked urine, with recoveries of 104 +/- 3 and 101 +/- 3, and the relative standard deviation of 3.3 and 3.4%, respectively. (C) 2000 Elsevier Science B.V. All rights reserved.