Feasibility of LC/TOFMS and elemental database searching as a spectral library for pesticides in food
Feasibility of LC/TOFMS and elemental database searching as a spectral library for pesticides in food
复制标题
DOI：
10.1080/02652030600838241
复制
发表时间：
2006-11
期刊：
影响因子：
--
通讯作者：
E. Thurman;I. Ferrer;Octavio Malato;A. Fernández-Alba
中科院分区：
文献类型：
--
作者：
E. Thurman;I. Ferrer;Octavio Malato;A. Fernández-Alba
传统上，食品中未知农药的筛查是通过 GC/MS 方法使用传统的图书馆检索程序完成的。然而，许多新型极性和热不稳定农药更容易通过 LC/MS 方法进行分析，并且目前不存在可搜索的库（除了一些有限的用户库）。因此，需要能够检测农药及其降解产物的 LC/MS 库。本文报告了一种结合使用 LC/MS 飞行时间（精确质量）和包含 350 种适合正离子电喷雾的农药的 Access 数据库的识别方案。该方法不同于传统的碎片离子库搜索。该概念由三个部分组成：(1) 使用精确质量对实际市场水果提取物（苹果和橙子）中可能存在的农药进行初步筛查，并通过自动离子提取程序生成精确质量，(2) 手动搜索 Access 数据库以筛选鉴定农药，以及 (3) 通过至少一种碎片离子的精确质量以及保留时间与实际标准品的比较来鉴定可疑化合物。使用该数据库方法鉴定了苹果中的抑霉唑和异菌脲以及橙子中的噻菌灵。
Traditionally, the screening of unknown pesticides in food has been accomplished by GC/MS methods using conventional library-searching routines. However, many of the new polar and thermally labile pesticides are more readily and easily analysed by LC/MS methods and no searchable libraries currently exist (with the exception of some user libraries, which are limited). Therefore, there is a need for LC/MS libraries that can detect pesticides and their degradation products. This paper reports an identification scheme using a combination of LC/MS time-of-flight (accurate mass) and an Access database of 350 pesticides that are amenable to positive ion electrospray. The approach differs from conventional library searching of fragment ions. The concept consists of three parts: (1) initial screening of possible pesticides in actual market-place fruit extracts (apple and orange) using accurate mass and generating an accurate mass via an automatic ion-extraction routine, (2) searching the Access database manually for screening identification of a pesticide, and (3) identification of the suspected compound by accurate mass of at least one fragment ion and comparison of retention time with an actual standard. Imazalil and iprodione were identified in apples and thiabendazole in oranges using this database approach.