Comparison of QuEChERS sample preparation methods for the analysis of pesticide residues in fruits and vegetables.

Quick, Easy, Cheap, Effective, Rugged, and Safe (QuEChERS) is an extraction and clean-up technique originally developed for recovering pesticide residues from fruits and vegetables. Since its introduction, and until December 2013, about 700 papers have been published using the QuEChERS technique, according to a literature overview carried out using SciFinder, Elsevier SciVerse, and Google search engines. Most of these papers were dedicated to pesticide multiresidue analysis in food matrices, and this topic has been thoroughly reviewed over recent years. The QuEChERS approach is now rapidly developing beyond its original field of application to analytes other than pesticides, and matrices other than food, such as biological fluids and non-edible plants, including Chinese medicinal plants. Recently, the QuEChERS concept has spread to environmental applications by analyzing not only pesticides but also other compounds of environmental concern in soil, sediments, and water. To the best of our knowledge, QuEChERS environmental applications have not been reviewed so far; therefore, in this contribution, after a general discussion on the evolution and changes of the original QuEChERS method, a critical survey of the literature regarding environmental applications of conventional and modified QuEChERS methodology is provided. The overall recoveries obtained with QuEChERS and other extraction approaches (e.g., accelerated solvent extraction, ultrasonic solvent extraction, liquid/solid extraction, and soxhlet extraction) were compared, providing evidence for QuEChERS higher recoveries for various classes of compounds, such as biopesticides, chloroalkanes, phenols, and perfluoroalkyl substances. The role of physicochemical properties of soil (i.e., clay and organic carbon content, as well as cation exchange capacity) and target analytes (i.e., log KOW, water solubility, and vapor pressure) were also evaluated in order to interpret recovery and matrix effect data.

QuEChERS sample preparation for the determination of pesticides and other organic residues in environmental matrices: a critical review

Variability of matrix effects in liquid and gas chromatography-mass spectrometry analysis of pesticide residues after QuEChERS sample preparation of different food crops.

Review of pesticide residue analysis in fruits and vegetables. Pre-treatment, extraction and detection techniques

Analysis of pesticides and their metabolites in food and water matrices continues to be an active research area closely related to food safety and environmental issues. This review discusses the most widely applied mass spectrometric (MS) approaches to pesticide residues analysis over the last few years. The main techniques for sample preparation remain solvent extraction and solid-phase extraction. The QuEChERS (Quick, Easy, Cheap, Effective, Rugged, Safe) approach is being increasingly used for the development of multi-class pesticide residues methods in various sample matrices. MS detectors-triple quadrupole (QqQ), ion-trap (IT), quadrupole linear ion trap (QqLIT), time-of-flight (TOF), and quadrupole time-of-flight (QqTOF)-have been established as powerful analytical tools sharing a primary role in the detection/quantification and/or identification/confirmation of pesticides and their metabolites. Recent developments in analytical instrumentation have enabled coupling of ultra-performance liquid chromatography (UPLC) and fast gas chromatography (GC) with MS detectors, and faster analysis for a greater number of pesticides. The newly developed "ambient-ionization" MS techniques (e.g., desorption electrospray ionization, DESI, and direct analysis in real time, DART) hyphenated with high-resolution MS platforms without liquid chromatography separation, and sometimes with minimum pre-treatment, have shown potential for pesticide residue screening. The recently introduced Orbitrap mass spectrometers can provide high resolving power and mass accuracy, to tackle complex analytical problems involved in pesticide residue analysis.

Current mass spectrometry strategies for the analysis of pesticides and their metabolites in food and water matrices.

Fast gas chromatography for pesticide residues analysis using analyte protectants

Analysis of pesticide residues by fast gas chromatography in combination with negative chemical ionization mass spectrometry.

A fast gas chromatographic–mass spectrometric (GC–MS) method is proposed for pesticide multiresidue analysis of apples. The QuEChERS method was used for sample preparation. GC–MS analysis was performed with a PTV, an autoinjector, and a quadrupole benchtop MS detector. Electron-impact ionization (70 eV) was used with two modes of selected ion monitoring. Compounds were separated under temperature-programmed conditions on a narrow-bore diphenyldimethylsiloxane column. In one chromatographic run 61 pesticides of different chemical classes, and triphenyl phosphate as internal standard, were determined in 11 min. Calibration was performed with matrix-matched standard solutions and response to the pesticides was a linear function of concentration in the range 1–500 ng mL−1 (equivalent to 1–500 μg kg−1 in real samples). High values of the determination coefficients (R2; 0.9900–1.0000) were obtained for most of the pesticides. Limits of detection and quantification were determined. When the method was used for analysis of pesticide residues in real samples, five pesticides were detected at concentrations in the range 1.00–21.47 μg kg−1. Repeatability of measurements, expressed as relative standard deviations of absolute peak areas, normalized relative to TPP, and of the concentrations determined, met the EU criterion of RSD ≤ 20%. Use of the internal standard moderately improved quantitative results.

Fast GC–MS Pesticide Multiresidue Analysis of Apples

Comparison of negative chemical ionization and electron impact ionization in gas chromatography-mass spectrometry of endocrine disrupting pesticides.

In the analysis of pesticide residues by GC including GC-MS, adverse effects caused by matrix co-extractives occurs which results in worse precision and trueness of analytical results. Sample extra...

Renáta Húšková

Papers

Fast gas chromatography for pesticide residues analysis using analyte protectants

Analysis of pesticide residues by fast gas chromatography in combination with negative chemical ionization mass spectrometry.

Fast GC–MS Pesticide Multiresidue Analysis of Apples

Comparison of negative chemical ionization and electron impact ionization in gas chromatography-mass spectrometry of endocrine disrupting pesticides.

Evaluation of different calibration approaches in pesticide residues analysis in non-fatty food using fast GC-MS