气相色谱法测定玉米中的高效氯氰菊酯残留

Gas Chromatographic Analysis of Beta-cypermethrin Residue in Maize

研究了玉米植株、鲜食玉米籽粒和玉米粉中高效氯氰菊酯残留分析方法。植株和鲜食籽粒中高效氯氰菊酯经丙酮：石油醚（体积比1：1）高速匀浆提取；玉米粉中的高效氯氰菊酯用丙酮超声提取；提取物用弗罗里硅土＋氧化铝净化；用带ECD检测器的气相色谱仪进行测定。高效氯氰菊酯的最低检出量为1．0×10-12 g，在植株、玉米粉和鲜食籽粒中的最低检出浓度为0．001mg／kg，平均回收率在94．2％～104％之间，相对标准偏差为2．3％～7．0％，符合残留分析要求。

The methods for determination of beta - cypermethrin residue in plants, fresh kernels and kernel powder of maize by gas chromatographic （GC） analysis were studied. The beta - cypermethrin residued in plants and fresh kernels were extracted by a mixture of acetone and petroleum ether with the volume ratio of 1： 1 after homogenized, while that in maize kernel powder was extracted by acetone after ultrasonic treatment. The extracts were purified by Florisil and Al2O3, and determined by GC with ECD detector. The minimum detectable limit of beta -cypermethrin was 1.0 × 10-12 g and its minimum detectable concentration was 0. 001 mg/kg with the recovery rate ranged from 94. 2% to 104% and the relative standard deviation of 2. 3%- 7.0%. So this method could meet the need of residue analysis of beta - cvoermethrin.