Simultaneous Determination of Organophosphate and Phenoxy-based Herbicides in Black Tea using LC-MS/MS and QuPPePretreatment

User Benefits

- An LC-MS/MS method is established for simultaneous analysis of highly-polar organophosphate-based herbicides (glyphosate, glufosinate, AMPA) and less-polar phenoxy-based herbicides (MCPA, 2,4-D, 4-CPA) in black tea on LCMS-8060NX. - The results of intra-day and inter-day performance evaluation indicate the acceptable sensitivity, precision and stability against the MRLs set by the EU and JP authorities.

Introduction

Organophophate and phenoxy-based herbicides are commonly used in agriculture and tea plantation. Due to potential health hazards, maximum residue limits (MRLs) of these herbicides in various food products have been established by authorities around the world. Concurrent screening of multiple herbicides is desired, but different LC-MS/MS methods and columns are often used for analysis of different groups of herbicides due to the substantial differences in properties and retention chemistry. For instance, glyphosate and glufosinate (organophophate) cannot be well retained and separated with C18 or phenyl LC columns due to their high polarity. The EURL-SRM has recommended specific LC-MS/MS methods and QuPe pretreatment to handle such highly-polar herbicides and pesticides in food commodities. In this application news, a sensitive LC-MS/MS method is described for simultaneous analysis of five commonly-used herbicides (and a toxic metabolite) in tea plantations in South Asia countries. A mixed-mode LC column was used for analysis of glyphosate, glufosinate, AMPA (metabolite), MCPA, 2,4-D and 4-CPA in black tea on the LCMS-8060NX, a tandem LC-MS/MS system with an ion-focus ESI interface.

April 27, 2022 GMT