气相色谱测定江永香姜中有机磷农药残留

Determination of Oganophosphorus Pesticide Residues in Jiangyong Sweet-smelting Ginger by Gas Chromatography

为建立气相色谱法(GC)测定江永香姜中有机磷农药残留量的分析方法,从永州市江永县采集香姜试样,将试样用含体积比为1%乙酸的乙腈溶液提取,再经无水硫酸镁和醋酸钠净化,以C18色谱柱分离待测物,基质匹配标准溶液外标法定量,最后用气相色谱法(GC)法检测香姜中有机氯农药残留,从而达到定性的效果.试验表明,6种有机磷农药在0~1 mg/L的范围内线性关系良好,相关系数均大于0.990,检出限为0.012~0.071mg/kg,相对标准偏差2.22%~9.30%,试样添加回收试验的平均回收率为68.0%~111.0%.以上结果表明,气相色谱法具有测定有机磷农药种类多、净化效果好、准确度和精密度高等优点,能够满足香姜农药残留检测要求.

To establish a detection method for the organophosphorus pesticides residues in Jiang Yong sweet-smelting ginger by Gas Chromatography, samples of sweet-smelting ginger were col- lected from Jiangyong County,Yongzhou City.The sample was extracted by acetonitrile solution containing 1% acetic acid,purified by anhydrous magnesium sulfate and sodium acetate,seper- ated by C18 chromatographic column,tested by matrix matching external standard method of quantitative standard solution,finally gas chromatography （GC） method was used to detect or- ganochlorine pesticide residues in the fragrant ginger to achieve the qualitative goals.Under above conditions,the standard linear range of organochlorine pesticides was 0-1 mg/L;correlation coefficient r was above 0.99,the minimum detection limits were 0.012-0.071 mg/kg,the relative standard deviations （RSDs） were 2.22%-9.30% and the recycling test sample of average recoveries were 68. 0% - 111.0%.The results show that this method has the merits of good purifying effects, high accuracy and precision. It is accorded with pesticide residues testing standards in sweet-smelting ginger at home and abroad.