微波辅助提取-气相色谱法同时测定中草药中有机磷和氨基甲酸酯农药残留

建立了中草药中有机磷和氨基甲酸酯类农药同时检测的气相色谱分析新方法.中药材试样依据正交实验的优化条件,用正己烷-丙酮(1∶4,V∶V)混合提取剂进行微波辅助提取,经弗罗里硅土和中性氧化铝混合层析柱净化后,采用HP-5毛细管柱分离,氮磷检测器同时检测中草药中15种有机磷和6种氨基甲酸酯类农药残留量.21种农药在0.01～1.0 mg/L的浓度范围内线性良好,线性相关系数为0.9950～1.000,检出限为0.002～0.01 mg/L.在0.05、0.2、0.5 mg/kg三个添加水平的平均回收率分别为75.11%～128.57%、75.85%～120.71%和76.43%～117.25%,相对标准偏差分别为 3.10%～10.58%、5.27%～9.94%和4.03%～9.03%.方法用于中草药中有机磷和氨基甲酸酯类农药残留的同时检测,结果良好.

Determination of Organophosphorus and Carbamate Pesticide Residues in Chinese Herbal Medicines by Gas Chromatography and Microwave-assisted Extration

A new method for the simultaneous determination of organophosphorus and carbamate pesticide residues in Chinese herbal medicines by gas chromatography has been proposed. Extraction conditions were optimized using orthogonal experimental design. The 15 organophosphorus and 6 carbamate pesticide residues in Chinese herbal medicine were extracted by microwave-assisted extraction with hexane-acetone (1∶4, V∶V) as slovent. The post-extraction organic phase was cleaned up by a column filled with florisil and neutral aluminum oxide. And the analytical screening was determined by gas chromatography using HP-5 capillary column equipped with nitrogen-phosphorus detector. The proposed method show a good linearity between analytical signal and analyte concentration in the range of 0.01～1.0 mg/L with the linear correlation coefficients of 0.9950～1.000 and limits of detection of 0.002～0.01 mg/L. The average recoveries obtained from samples spiked with standards at the concentration levels of 0.05 mg/kg; 0.2 mg/kg and 0.5 mg/kg were in the range of 75.11%～128.57%; 75.85%～120.71% and 76.43%～117.25%, respectively, with relative standard deviations of 3.10%～10.58%; 5.27%～9.94% and 4.03%～9.03%, respectively. A satisfactory result was obtained by the simultaneous determination of organophosphorus and carbamate pesticide residues in Chinese herbal medicines.