加速溶剂萃取-气相色谱-质谱法检测谷物中农药多残留的研究

Multi-residue Determination of Pesticides in Cereals Using Accelerated Solvent Extraction and Gas Chromatography-mass Spectrometry

将加速溶剂萃取法和气相色谱-质谱检测法相结合，建立了一种测定谷物中农药多残留的新方法。优化了加速溶剂萃取（ASE）法提取谷物中农药多残留的条件，采用丙酮＋正己烷（1＋1）作为萃取剂，萃取温度为80℃，萃取压力为10．3MPa。萃取液经过浓缩，过活性炭固相萃取（SPE）柱净化后，用气相色谱-质谱仪（GC—MS）检测，内标法定量。以大米和玉米为基质进行添加回收试验，结果表明：大米中的农药添加回收率为78．9％～105．3％，RSD≤12．8％；玉米中的农药添加回收率为80．9％-106．2％，RSD≤13．6％大米和玉米中农药的检出限（LOD）分别为0．3—3．6μg／kg和0．3—4．0μg/kg。

A multi-residue method based on accelerated solvent extraction （ASE） and gas chromatography-mass spectrometry （ GC- MS） was studied to determine pesticides in cereals. The optimum extracting agent was acetone and hexane （ 1 ＋ 1 ）, the extracting temperature was 80 ℃ and the extracting pressure was 10.3 MPa. After concentrated and purified, the extracts were determined by gas chromatography-mass spectrometry and quantified with internal standard method. The results showed that the recoveries were 78.9% - 105.3% for rice with RSD ≤ 12.8% and 80.9% - 106.2% for maize with RSD ≤13.6% in two spiked concentration levels. The limits of detection （LODs） were 0.3 - 3.6 μg/kg for rice and 0.3 - 4.0 μg/kg for maize.