GC-ECD法测定5种保健食品中六六六和滴滴涕的农药残留

摘要

目的：建立毛细管气相色谱法测定保健食品中六六六和滴滴涕残留的方法。方法：样品中的六六六、滴滴涕经过石油醚（30℃~60℃）提取、浓硫酸净化以及浓缩后，采用毛细管气相色谱法进行分离。色谱条件：DM-5弹性石英毛细管柱（30 m×0.32 mm，0.25μm)；电子捕获检测器（ECD）；载气为高纯氮气，柱流量为1.0 mL·min-1；进样口温度为230℃；检测器温度为300℃；进样量为1μL；程序升温：初始温度150℃，以10℃·min-1升至250℃，保持5 min。结果：六六六、滴滴涕测定的线性关系良好，回收率为72.6%~96.5%，六六六的检测限为1.1μg·kg-1，滴滴涕的检测限为1.8μg·kg-1。结论：该法操作简便，准确，灵敏度高，可以满足保健食品中六六六、滴滴涕农药残留检测的需要，为保健食品的质量控制提供依据。%Objective: To establish a method for determination of residues of hexachlorocyclohexane (HCH) and clofenotane (DDT) in dietary supplements by GC-ECD. Methods: The samples were determined by capillary gas chromatography after petroleum ether extraction, sulphuric acid purification and concentration. The chromatographic conditions were as follows: the capillary column was DM-5 (30 m×0.32 mm, 0.25 μm) with an ECD detector; the carrier gas was high purity nitrogen and the column flow rate was 1.0 mL·min-1 (constant flow); the flow rate of make-up gas was 30 mL·min-1; the temperature was 230℃for splitless sampling inlet and 300℃ for detector, the column temperature was initially 150℃, raised at 10℃·min-1 to 250℃ and kept for 5 min. Results: The detection linearity of HCH and DDT were very good, the recovery rates were 72.6%-96.5%, the detection limits were 1.1μg·kg-1 for HCH and 1.8μg·kg-1 for DDT. Conclusion: This method can meet the needs for determination of HCH and DDT residues in dietary supplements, which is simple, accurate, highly sensitive and provides basis for quality control.