Determination of Butyltin Compounds in Seawater by Headspacesolidphase Microextractiongas Chromatography

Abstract:

A method for simultaneous determination of three organotin compounds named monobutyltin (MBT),dibutyltin (DBT),tributyltin (TBT) in seawater sample was described.The method was based on derivatization with sodium tetraethylborate followed by headspacedsolidphase microextraction (SPME) combined with gas chromatographyflame ionization detector (GCFID).The SPME conditions were optimized using experimental designs (five factors and for levels).The calibration ranges of MBT,DBT and TBT are 0.05~1 000 μg·L-1， 0.02~1 000 μg·L-1，0.02~1 000 μg·L-1(as Sn).The detection limits of MBT,DBT and TBT are 50，8，8 ng·L-1(as Sn).The recoveries of MBT,DBT and TBT are 106%，89%，91% by analyzing seawater spiked with organotin compounds.Six samples taken from six cities (Shenzhen,Shanghai,Lianyungang,Qingdao,Dalian,Yantai) were analyzed,and organotin compounds were detected in all five samples but Qingdao.

Key words:organotin compounds; derivatization; experimental design; SPMEGCFID