A simple method was developed for quantitative analysis of bis(tri-n-butyltin) oxide (TBTO) in cultured fresh fish by high-performance liquid chromatography (HPLC). The sample was decomposed with alkaline alcohol and TBTO was converted into tri-n-butyltin chloride (TBTC), which was then purified by a cation exchange method. TBTC was determined by HPLC with a cation exchange column and an ultraviolet absorption detector.
The recoveries of TBTO added to the muscle of yellowtail and sea bream at the level of 2ppm were 87±4 and 87±3%, respectively, and that of TBTO added to the muscle of spanish mackerel at the level of 0.2ppm was 90±5%. The detection limit of TBTO was 0.1ppm.
The concentrations of TBTO in cultured fresh fishes could be easily quantified by this method.