A gas chromatography-mass spectrometric(GC-MS) method was developed for the simultaneous determination of toluene,o-xylene,m-xylene,p-xylene,N,N-dimethyl formamide(DMF) and dimethyl sulfoxide(DMSO) residues in agro products.The target compounds were extracted from various vegetables and crops by acetonitrile solution,and further analyzed by GC-MS in selected ion monitoring after chromatographic separation on an Agilent DB-624(30.0 m×250 μm×1.4 μm) column.Identification was achieved by the retention time and the ion ratio,and quantification was done by the external standard method.The results showed that the calibration curves were linear in the range of 0.005-0.500 mg/L for toluene,p-xylene,o-xylene and m-xylene,0.025-0.125 mg/L for DMF,and 0.050-0.500 mg/L for DMSO,with correlation coefficients of 0.992 0-0.997 1.The spiked recoveries of six organic solvents residues were in the range of 60.1%-115.2% with relative standard deviations(RSDs) not more than 11.0%.The limits of detection were in the range of 0.002-0.050 mg/kg for benzene series,0.010-0.025 mg/kg for DMF,and 0.060-0.150 mg/kg for DMSO.The method is simple,rapid,sensitive and accurate,and could be used for the simultaneous determination of volatile organic solvents residual in agricultural products.
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气相色谱-质谱有机溶剂农产品液液萃取
Keywords
gas chromatography-mass spectrometry(GC-MS)organic solventsagricultural productsliquid-liquid extraction