High Capacity Headspace Sorptive Extraction (HSSE)

A new approach for sorptive enrichment of analytes from the headspace of aqueous or solid samples, referred to as headspace sorptive extraction (HSSE) is described. The technique implies the sorption of volatile and semivolatile compounds into a large amount of polydimethylsiloxane (ca. 50 mg) placed on a glass rod support. The polydimethylsiloxane (PDMS) coated rod is fixed in the head of a closed vial or erlenmeyer and the sample is equilibrated for 30-60 min. The PDMS coated glass bar is then thermally desorbed on-line with capillary gas chromatography-mass spectroscopy (GC-MS). Using a large amount of sorptive phase highly volatile compounds can be efficiently enriched and compared to solid phase microextraction on a 100 m PDMS fiber where a significant increase in sensitivity is achieved. Limits of detection are in the ng L-1 (ppt) range. The potential of HSSE is illustrated with the analysis of some food samples.