High capacity headspace sorptive extraction

A new approach for sorptive enrichment of analytes from the headspace of aq ueous or solid samples, referred to as headspace sorptive extraction (HSSE) is described. The technique implies the sorption of volatile and semivolat ile compounds into a large amount of polydimethylsiloxane (ca. 50 mg) place d on a glass rod support. The polydimethylsiloxane (PDMS) coated rod is fix ed in the head of a closed vial or erlenmeyer and the sample is equilibrate d for 30-60 min. The PDMS coated glass bar is then thermally desorbed on-li ne with capillary gas chromatography-mass spectroscopy (GC-MS). Using a lar ge amount of sorptive phase highly volatile compounds can be efficiently en riched and compared to solid phase microextraction on a 100 mum PDMS fiber where a significant increase in sensitivity is achieved. Limits of detectio n are in the ng L-1 (ppt) range. The potential of HSSE is illustrated with the analysis of some food samples. (C) 2001 John Wiley & Sons, Inc.