Analysis of Pesticide Residues in Cannabis using QuEChERS and HPLC

Introduction

For pesticide analysis of cannabis, many labs have adopted the “quick, easy, cheap, effective, rugged & safe” (QuEChERS) method. There are several issues which may be encountered with this approach, including highly pigmented extracts, interference/ contamination from co-extracted cannabinoids, and poor peak shapes for early eluting peaks in HPLC analysis.

In this work, an approach for analysis of many of the pesticides required for testing by the state of Oregon was developed. Analysis of this list requires the use of both GC and LC. Topics such as sample cleanup and HPLC column and mobile phase selection were studied in order to enable analysis of a single set of QuEChERS extracts by GC/MS/MS and LC/MS/MS.