Supercritical fluid extraction and clean-up of organochlorine pesticides in ginseng

A method involving the simultaneous extraction and clean-up of nine organochlorine pesticides (OCPs) from the actual ginseng was developed using supercritical fluid extraction (SFE) and off-line solid-phase extraction (SPE) cartridge. The pesticides in the study consisted of α-, β-, γ- and δ-benzene hexachloride (BHC), pentchloronitrobenzene and DDT and its metabolites. The target analytes extracted were collected with an off-line commercial solid-phase extraction cartridge, recovered with eluting solvent and quantified by gas chromatography-electron-capture detection together with mass spectrometric confirmation. The optimal extraction conditions was obtained from a series of experiments in which samples preloaded by 10 wt.% ethanol–H2O solutions, 300 bar extraction pressure, 60 °C extraction temperature, with C18 as trap adsorbent and n-hexane as eluting solvent. Additionally, Soxhlet extraction of organochlorine pesticides in actual ginseng was also carried out. Experimental results showed that SFE was more rapid and more effective than Soxhlet extraction.