A rapid and efficient method based on the integration of pressurized solvent extraction (PSE) with solid phase extraction (SPE) cleanup and gas chromatography system with electron capture detection (GC-ECD) has been developed for determination of polychlorinated biphenyls (PCBs). Six indicators and twelve dioxin-like PCBs were selected as analytes. This method is based on the integration of solvent extraction and cleanup processes inside a pressurized stainless steel cell. The optimum extraction conditions were 6 min of extraction at 70 °C and two cycles of extraction using hexane/methylene chloride (1:1, v/v) as the extraction solvent. Silica gel acidified with sulfuric acid was used for integrated cleanup of the organic extract. This method allows a significant reduction in extraction time and solvent consumption. Repeatability, expressed as the relative standard deviation, ranged from 3 to 6%, and recoveries for concentration of 20 ng g-1 was ranged between 71 to 104% .The limit of detection and quantification ranged from 0.03 to 0.29 ng g-1 and 0.1 to 0.97 ng g-1 respectively. The linear range was between 5 and 100 ng g-1 . Finally this new method was applied to samples of chicken and pork.
pressurized solvent extraction; integrated extraction-cleanup; polychlorinated biphenyls; chicken and pork; GC-ECD
