分散固相萃取净化液相色谱-质谱联用快速检测糙米中的多种残留农药

Determination of pesticide residues in unpolished rice by high performance liquid chromatography-electrospray ionization mass spectrometry

建立了同时检测糙米中多种农药残留的分析方法。采用乙腈提取，使用N-丙基乙二胺键合固相吸附材料（PSA）和C18硅胶胶联吸附剂分散固相萃取（dispersive-SPE）净化，高效液相色谱-电喷雾串联质谱，正离子模式检测，内标法定量。30种农药在0．05～2mg／kg范围内线性良好，方法检出限和定量限分别为0．5-20μg／kg和2～60μg／kg，30种农药平均回收率在73％～109％之间，相对标准偏差〈10％，均能够满足农药残留分析的要求。

A method based on dispersive-SPE determining pesticide residues in unpolished rice by high performance liquid ehromatography-electrospray ionization mass spectrometry was developed. The mass spectrometer was operated with electrospray in the positive ion mode （ESI^＋）. The target analytes were quantified by internal standard method and matrix-matched standard solution used to compensate for matrix effect. The sample was extracted by acetonitrile and cleaned up by dispersive solid phase extraction using primary secondary amine （PSA） and Cl8-bonded silica dispersant sorbent. Good linears were obtained ranging from 0.05 to 2 mg/kg. Detection and quantification limits were 0.5-20μg/kg and 2-60 μg/kg respectively. Average recoveries ranged from 73% to 109% and relative standard deviations were less than 10% at three fortified levels.