固相萃取-超高效液相色谱串联质谱测定茶产品中吡蚜酮

建立了Cleanert PCX固相萃取,超高效液相色谱-串联质谱(UPLC-MS/MS)测定干茶、抹茶和速溶茶粉中吡蚜酮残留量的分析方法。干茶、抹茶和速溶茶粉中的吡蚜酮经甲醇和水的混合溶液提取、Cleanert PCX固相萃取柱富集净化和Acquity BEH C18色谱柱分离后,通过UPLC-MS/MS多反应监测模式(MRM)测定,外标法定量。在0.005~1.000 mg·kg^-1添加范围内,吡蚜酮的平均回收率为77.0%~95.1%,相对标准偏差(RSD,n=5)为1.8%~6.9%,方法的定量限(LOQ)为0.005~0.010 mg·kg^-1。该方法在灵敏度、准确度和回收率上均符合农药残留检测的要求,可为茶产品中吡蚜酮残留量的测定和风险评估提供分析方法。

Determination of Pymetrozine in Tea Products by Solid Phase Extraction-Ultra High Performance Liquid Chromatography-Tandem Mass Spectrometry

An analytical method for the determination of pymetrozine residues in tea products, including dry tea, matcha and instant tea powder, was established based on Cleanert PCX solid phase extraction-ultra high performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). The residual pymetrozine in dry tea, matcha and instant tea powder was extracted by a mixture of methanol and water, cleaned up and concentrated by a Cleanert PCX SPE column, and separated on an Acquity BEH C₁₈ column. Pymetrozine level was detected by UPLC-MS/MS on multiple reaction monitoring (MRM) mode and quantified with external standard method. In the spiked range of 0.005-1.000 mg·kg^-1, the average recovery of pymetrozine was 77.0%-95.1%, and the relative standard deviation (RSD, n=5) ranged from 1.8%-6.9%. The limit of quantitation (LOQ) was 0.005 to 0.010 mg·kg^-1. The sensitivity, precision and recovery of the developed method meet the requirements for residual pesticides analysis in various tea products. The results of this study can provide an analytical method for the determination and risk assessment of pymetrozine in tea products.