Determination of inorganic and organotin compounds in sea water by graphite furnace atomic absorption spectrometry

Abstract

Inorganic tin and organotin compounds in artificial sea water were determined at sub-p.p.b. levels. These compounds are separated from matrix elements in aqueous solutions by benzene extraction of their iodide forms from a 2 M sulphuric acid-1.5 M sodium iodide solution containing 1%m/V ascorbic acid. The organic phase was partially vaporised to pre-concentrate the analytes and was injected directly into the treated graphite tube; the signal was measured by a Zeeman atomic absorption spectrometer. Using a matrix modifier, inorganic tin could be directly determined at sub-p.p.m. levels in the presence of organotin compounds.