COMPREHENSIVE EVALUATION OF THE EXTRACTION VARIABLES AFFECTING THE DETERMINATION AND STABILITY OF NATIVE BUTYL-TIN AND PHENYL-TIN COMPOUNDSFROM SEDIMENT

The effect of several extraction variables; such as acid concentration and strength (e.g. for HCl and HOAc), the presence of complexing agen ts (e.g. tropolone, sodium diethyldithiocarbamate) in the extracting m ixture, solvent polarity (e.g, hexane, toluene) and sonication time fo r native butyl- and phenyl-tin compounds from sediment was evaluated. A toluene-HOAc mixture (10:4) yields the highest extraction efficiency for all the analytes and minimizes the degradation of trialkyl- and t riaryl-tins during the extraction under sonication, In addition, losse s of underivatized monobutyltin and monophenyltin were minimized in se veral steps of the analytical procedure. The analytical procedure deve loped was validated against existing CRMs for butyltin determination. (C) 1998 John Wiley & Sons, Ltd.