EXAMINATION OF THE DIFFERENT PROCEDURAL STEPS IN THE DETERMINATION OF ORGANOTIN COMPOUNDS IN WATER SAMPLES

The different steps in the proposed DIN (Deutsche Industrie Norm) procedure for the determination of organotin compounds in water samples were examined by means of a gas chromatography-mass spectrometry system. In the proposed DIN-procedure the organotin compounds R(n)Sn((4-n)+) (with R = butyl (Bu), n = 1-4; R = heptyl (He), n = 1,2(as internal standards), R = octyl (Oc), n = 1, 2; R = phenyl (Ph), n = 3; R = cyclohexyl (c-Hex), n = 3) are extracted from acidified water samples by tropolone/hexane, derivatised with the Grignard reagent n-pentylmagnesium bromide, purified by solid phase extraction and determined after solvent evaporation. In this study the stability of the analytes in the samples, the extraction and the chromatographic purification step as well as a possible evaporation of the organotin compounds were examined.