CAPILLARY GAS-CHROMATOGRAPHY ICP MASS-SPECTROMETRY - A POWERFUL HYPHENATED TECHNIQUE FOR THE DETERMINATION OF ORGANOMETALLIC COMPOUNDS

The development and improvement of agas chromatography inductively cou pled plasma mass spectrometry system, CC-TCP-MS, is described. The GC and ICP-MS are coupled with a heated stainless steel transfer line. Xe . present in the GC carrier gas, is used to facilitate the nebuliser g as flow rate setting and the positioning of the torch. Alkyltin compou nds are separated by GC using a 30 m capillary column within 9 min. Th e necessity of applying double internal standardisation (use of Bu(3)P eSn and Xe gas as internal standards) is shown. The repeatabilities al 50 mu g/l concentration for both retention time and Feal; are better than 0.25% and 5%, respectively. The detection limits for alkyltin com pounds are better than those of existing methods and range between 15 and 35 fg Sn. Finally GC-ICP-MS is applied to the determination of mon o-, di- and tributyltin in some harbour waters, after extraction and G rignard derivation with PrMgCl. Concentrations between 1 and 20 ng/l a re found.