标题：Reduction of matrix effects through a simplified QuEChERS method and using small injection volumes in a LC-MS/MS system for the determination of 28 pesticides in fruits and vegetables
作者：Li, Honge; Wang, Chenchen; Zhu, Qian; Du, Hongxia; Guan, Shuai; Wang, Fengen; Zhang, Wenjun; Fan, Wenjing; Chen, Zilei; Yang, Guoshe 更多 作者机构：[Li, Honge; Wang, Chenchen; Yang, Guosheng] Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China.; [Zhu, Qian; Du, Hongxia; Guan, Shua 更多
通讯作者地址：[Yang, GS]Shandong Univ, Sch Chem & Chem Engn, Jinan 250100, Peoples R China;[Chen, ZL]Shandong Acad Agr Sci, Cent Lab, Key Lab Test Technol Food Qual 更多
摘要：A simplified QuEChERS method coupled with a small injection volume was developed for the simultaneous determination of 28 pesticides in 6 matrices (apples, cucumbers, tomatoes, luffa, cabbages, and eggplants) using LC-MS/MS. In the sample procedure, acetonitrile with 0.1% (v/v) formic acid was used to extract and no depurative powder was used. Three fortified levels (10, 50, and 100 mu g kg(-1)) were determined and the recoveries of 168 analyte/matrix combinations were in the range of 60-120% except for cyromazin, pendimethalin, and fenpropathrin. Half of the 168 LOQs were below 0.1 mu g kg(-1), and 29 LOQs were above 1 mu g kg(-1). Moreover, four relationships between signal suppression and injection volume were observed ranging from 0.5 mu L to 15 mu L. For many analyte/matrix combinations, the matrix effects could be reduced to less than 20% if the injection volume was less than a critical value (named critical volume). The critical volume depending on the initial extent of matrix effects was explored and the conclusion was: for weak or medium MEs, usually <= 2 mu L injection volume was needed and for several weak MEs, injection volume <= 5 mu L can reduce the matrix effect to a negligible level.