Determination of tri-, di-, and monobutyltin and inorganic tin in biological materials and some aspects of their metabolism in rats.

A chromatographic method to separate and determine simultaneously trace amounts of tri-, di-, and monobutyltin and inorganic tin (IV) in biological materials has been established. These compounds were eluted stepwise on a silica gel column with an organic solvent system and were sensitively determined by flameless atomic absorption spectrophotometry. The calibration curves show linearity up to 6 mumol/L. The detection limit was 1.5 ng of tin for each of the tin compounds. The reproducibility and recovery were satisfactory. Tetra- and tributyltin were also sensitively determined by the gas chromatographic application of this method. This new method was applied to the study on the metabolism of tributyltin in rats. The contents of tributyltin in the liver of rats, to which a single oral dose of tributyltin fluoride had been administered, showed a rapid decrease following an initial transient increase. The tributyltin, once transported to the liver, seemed to be rapidly dealkylated. The most significant finding was the remarkable retention of monobutyltin and inorganic tin (IV) in the brain.