A Highly Sensitive Method for Determination of Monobutyltin in Aqueous Media by Stripping Voltammetry at a Renewable Silver Amalgam Annular Band Electrode

An adsorptive stripping voltammetric (AdSV) procedure for the determination of monobutyltin in aqueous media at a silver liquid amalgam film‐modified silver solid amalgam annular band electrode (AgLAF? AgSAE) is described. Determination of monobutyltin proceeds in two steps. At the beginning monobutyltin ions (BuSn³⁺) are accumulated from 0.1 M NH₄NO₃ and 10 % ethanol solution at a potential of ?0.2 V, than the BuSn⁰ film is preconcentrated at the working electrode surface at a potential of ?0.7 V. After this step the DP AdSV voltammogram is recorded. The analytical parameters and the procedure of the electrode regeneration and activation were optimized. The calibration curve of monobutyltin in the range 0.02–0.30 mg L^?1 is linear (r=0.9973). The detection limit for 5 s of preconcentration, calculated as 3σ of the blank was equal to 0.004 mg L^?1, repeatability of the peak current was 1.8 % (n=5). Repeatability and sensitivity of monobutyltin determination depends strongly on the analyzed solution properties, measurement conditions and the working electrode quality. The proposed procedure was tested by means of monobutyltin determination in tap waters.