Analysis of Triorganotin Compounds by High‐Performance Liquid Chromatography with Reverse‐Pulse Amperometric Detection

Abstract

Abstract High‐performance liquid chromatography (HPLC) coupled with the reverse‐pulse amperometric (RPA) detection method has been developed for the analysis of triorganotin compounds in aqueous solutions. The major advantage of RPA vs. conventional amperometric detection is its ‘in situ’ elimination of interference from dissolved oxygen in the chromatographic eluent; therefore, no extra chemicals or apparatus are required for oxygen removal. With a Partisil‐10 SCX column and an eluent of methanol/0.01 M sodium acetate buffer (70:30, pH 5.5), the four triorganotins, viz., trimethyl‐, triethyl‐, tripropyl‐, and tributyltin, can be totally separated. Detection by RPA was performed with a static dropping mercury electrode with an initial potential of −1.15 V and a final potential of +0.15 V. The absolute detection limit (S/N = 3) ranged from 12 ng of tributyltin (as tin) to 0.3 μg of trimethyltin (as tin). Applications of the method to the analysis of trace tributyltin in marine antifoulant leachate and sea water are described.