Supercritical fluid extraction versus ultrasonic extraction for the analysis of polycyclic aromatic hydrocarbons from reference sediments

Supercritical Fluid Extraction (SFE) was investigated as a sample preparati on and preconcentration method for the determination of Polycyclic Aromatic Hydrocarbons (PAHs) in sediment samples by HPLC. Two reference materials f or PAHs were extracted under supercritical conditions. The data were compar ed with the certified values obtained by an interlaboratory investigation. A preliminary study was conducted in which the influences on recoveries of different variables were investigated. Additional to SFE a conventional ult rasonic extraction was carried out to compare and evaluate the method perfo rmance. The results from the preliminary method optimisation experiments in dicate that, under the condition used, recovery was most affected by using polar modifiers. This study also showed that except for the higher condense d PAHs the extraction efficiencies of SFE are comparable with those obtaine d by ultrasonic extraction.