Development of a matrix solid-phase dispersion-sonication extraction method for the determination of fungicides residues in ginseng extract

A rapid method based on matrix solid-phase dispersion (MSPD) was developed for the determination of pentachloronitrobenzene, pentachloroaniline, methylpentachloro-phenylsulphide and procymidone in ginseng extract using gas chromatography. The optimal conditions selected for MSPD extraction were as follows: after blending 5 mL of aqueous ginseng extract (10%, w/v) with Florisil (10 g), the mixture was passed into a small chromatographic column and extracted twice with 10 mL ethyl acetate–hexane solvent mixture (70:30, v/v) for 15 min in an ultrasonic bath at room temperature. The analytical performance of this method showed MSPD to be efficient, fast, simple and had little or no matrix effect. The method detection limits varied from 0.1 to 0.4 μg/L. Mean recoveries were found in the range of 83.5–97.4% and had a good linear relationship (r2 ⩾ 0.9987) with relative standard deviations less than 10%. The proposed method has proved to be a feasible one for the analysis of fungicide residues in ginseng extract.