DETERMINATION OF PCBS IN BIOLOGICAL SAMPLES USING ONLINE SFE-GC

Supercritical fluid extraction (SFE) directly coupled to capillary gas chromatography (GC) has been utilized for selective extraction of polychlorinated biphenyls (PCBs) from the lipid matrix in different biological species using basic alumina as a selective adsorbent. Recoveries were between 70 and 96% and the reproducibilities for all samples were between 3 and 6% relative standard deviation. On-line SFE-GC reduces the potential for sample contamination and loss of analyte as no sample handling or concentration procedures are needed between extraction and analysis. The method has been applied to samples with large differences in fat content and the fat content did not seem to influence the performance of the analysis. Solute trapping, choice of restrictor, extraction volume and detection limit are discussed.