气相色谱微池电子捕获检测器测定蜂蜡中6种杀螨剂药物残留

建立一种准确、快速、简便的蜂蜡中杀螨剂类药物多残留检测技术。样品经恒温水浴液- 液萃取、低温冷冻离心净化后用气相色谱微池电子捕获检测器测定。对提取溶剂的种类、体积及提取次数进行研究。结果表明：30.0mL 乙腈- 正己烷(V/V，2:1)是最佳提取溶剂。经两次冷冻及高速离心能将大部分的脂类基质去除。该方法的线性范围为0.01～4mg/L，相关系数均大于0.9878。检出限为0.96～4.69μg/kg，定量限为2.56～13.12μg/kg。该方法在3 个不同浓度水平的添加均有很好的回收率(83.8%～110.4%)，相对标准偏差为1.70%～6.60%。

Determination of Six Acaricide Residues in Beeswax by Gas Chromatography Coupled with a Micro-electron Capture Detector

An accurate, fast and convenient method for simultaneous determination of 6 acaricide residues in beeswax by gas chromatography coupled with a micro-electron capture detector (GC-MECD) was established. The sample was saturated with hexane and acetonitrile in water bath with constant temperature. After frozen and centrifugation at 10000 r/min, the extract was analyzed by GC-MECD. Effects of extraction solvent, solvent volume and extraction times on extraction efficiency were explored. The best extraction solvent was 30.0 mL of acetonitrile-hexane (V:V, 2:1). Twice freezing and high speed centrifugation could remove the interference of lipid matrix. This method exhibited an excellent linear relationship over the range of 0.01 to 4.0 mg/L with a correlation coefficient of larger than 0.9878. The limits of detection (LOD) for the 6 acaricides varied from 0.96 to 4.69 μg/kg. The average recovery rates of these analytes spiked at three different levels ranged from 83.8% to110.4%, and the relative standard deviations (RSD) from 1.70% to 6.60%.