New AppNote: Pesticides in Fruits and Vegetables

Fast and efficient automated multi-residue pesticide analysis in fruits and vegetables by Disposable Pipette Extraction (DPX) and gas chromatography / mass spectrometry (GC/MS)


One of the most important aspects of reducing pesticide exposure is monitoring of pesticide residues in foods. A number of analytical methods have been developed, many of them based on traditional liquid-liquid extraction, gelpermeation or solid phase extraction in combination with GC/MS or LC/MS. Recently, the QuEChERS (quick, easy, cheap, effective, rugged and safe) sample preparation methods have been developed to help monitor pesticides in a range of food samples. These methods, however, still require many
manual steps, such as centrifugation, leading to increased total analysis time. There is a need for a simple, reliable and readily automated technique to clean up QuEChERS type extracts in order to improve laboratory productivity for monitoring pesticide residues in foods.

In this study, we present a novel solid-phase extraction technique called disposable pipette extraction (DPX). The solid-phase sorbent contained in the DPX tip is loose, which permits mixing of solutions to provide unsurpassed extraction effi ciency and short equilibration times. DPX extractions are automated using the GERSTEL MultiPurpose Sampler (MPS), enabling efficient, high-throughput sample preparation. The GERSTEL DPX-Q and the DPX-Qg with graphitized carbon black, represent the only commercially available automated QuEChERS application for multi-residue analysis of pesticides.

Automated Multi-Residue Pesticide Analysis in Fruits and  Vegetables by Disposable Pipette Extraction (DPX) and Gas Chromatography/Mass Spectrometry