气相色谱法测定芒果中的苯醚甲环唑残留

Determination of difenoconazole residue in mango by gas chromatography

通过考察4种不同的样品前处理方法,建立了芒果中苯醚甲环唑残留量的气相色谱法快速分析方法.样品经乙腈涡旋提取,通过PSA和无水MgSO4高速离心净化,毛细管柱分离,气相色谱-电子捕获检测器（GC-ECD）检测,外标法（基质加标）定量.结果表明：该方法在苯醚甲环唑添加量为2～200 μg/L范围内线性相关性良好,R2=0.9991,最低检出限为0.005 mg/kg.样品在0.05、0.50、2.00 mg/kg 3个添加水平下的苯醚甲环唑回收率为90.5％～98.0％,相对标准偏差（RSD）为1.56％～3.40％.与另外3种方法相比,该方法具有操作简便、处理时间短、检测成本低、灵敏度高、定量准确等诸多优点,适合大批量样品的检测,已成功应用于实际样品的检测.

By examining four different pre-treatment methods, a rapid analytical method was developed for the determination of difenoconazole residue in mango by gas chromatography （GC） coupled with electron capture detector （ECD）. The difenoconazole was extracted by acetronitrile, purified by PSA and anhydrous MgSO4 and determined by GC-ECD with external standard method. A good linearity ranging from 2 to 200 μg/L was obtained and the correlation coefficient was 0.9991. Recoveries of difenoconazole were 90.5% to 98.0% at three spiked levels, 0.05, 0.50 and 2.00 mg/kg, with relative standard deviations （RSDs） of 1.56%-3.40% （n=3）. The limit of detection （LOD） was 0.005 mg/kg. Compared with the other three methods, this method was suitable for bulk sample detection since the developed method was rapid, simple, cheap, high efficient and sensitive. And it has been successfully applied to the market monitoring sample detection of mango.