Speciation of butylitin compounds in marine sediments with headspace solid phase microextraction and gas chromatography-mass spectrometry

摘要

A method for the determination of organotin compounds (monobutyl = MET, dibutyl = DET, and trib- utyltin = TET) in marine sediments by headspace Solid Phase Microextraction (SPME) has been developed. The analytical procedure involved 1) extraction of TET, DET and MET from sediments with HCI and methanol mix- ture, 2) in situ derivatization with sodium tetraethylborate and 3) headspace SPME extraction using a fiber coated with poly(dimethylsiloxane). The derivatized organotin compounds were desorbed into the splitless injector and simultaneously analyzed by gas chromatography -mass spectrometry. The analytical method was optimized with respect to derivatization reaction and extraction conditions. The de- tection limits obtained for MET, DET and TET ranged from 730 to 969 pg/g as Sn dry weight. Linear calibration curves were obtained for all analytes in the range of 30-1000 ng/L as Sn. Analysis ofa standard reference sed- iment (CRM 462) demonstrates the suitability of this method for the determination of butyltin compounds in marine sediments. The application to the determination of TET, DET and MET in a coastal marine sediment. is shown.