MULTIRESIDUE PESTICIDE ANALYSIS IN FRUITAND VEGETABLE COMMODITIES USING BOTH UPLC AND APGC ON A SINGLE MASS SPECTROMETER PLATFORM

Significance of the Topic

Pesticide residues pose a major challenge for food safety, requiring robust analytical methods to monitor compliance with regulatory Maximum Residue Levels (MRLs). Rapid, comprehensive multiresidue analysis supports surveillance programs and industry quality control by detecting a wide range of compounds in fruits and vegetables with high sensitivity and throughput.

Objectives and Study Overview

This study aims to demonstrate a unified workflow for analyzing around 200 pesticide residues in fruit and vegetable matrices using both ultra performance liquid chromatography tandem mass spectrometry (UPLC MS/MS) and gas chromatography with atmospheric pressure chemical ionization MS/MS (GC APGC MS/MS) on a single tandem quadrupole platform. Key goals include evaluating sensitivity, repeatability and linearity in compliance with SANTE guidelines, and minimizing downtime between LC and GC inlets.

Methodology and Instrumentation

The workflow begins with QuEChERS sample extraction and dispersive solid phase cleanup tailored to matrix type. Four commodity classes were tested: celery, lemon, corn and kale. Cleanup employed MgSO4, PSA and graphitized carbon black in proportions adapted to each sample. Instrumentation included an UPLC system with a C18 100 x 2.1 mm column at 1.7 micron particle size and a GC system with a 30 m Rxi 5MS column connected to a Xevo TQ-S micro mass spectrometer. The universal ion source enabled rapid switching between electrospray ionization for UPLC and proton transfer APGC mode for GC without manual reconfiguration. Methods were generated and maintained via a centralized database tool for streamlined method development and data processing.

Results and Discussion

The Xevo TQ-S micro delivered fast scan speeds, acquiring at least two multiple reaction monitoring transitions per analyte with over twelve data points per peak. Matrix matched calibration from 0.001 to 0.050 mg per kg achieved correlation coefficients above 0.995 for most compounds, with APGC data fitting quadratic models and UPLC showing linear response. At the standard 0.010 mg per kg level, over 99 per cent of pesticides were detected across matrices with precision better than ten per cent relative standard deviation in triplicate tests. APGC performance on kale showed slightly reduced repeatability with eighty per cent of analytes under ten per cent RSD. Ion ratio tolerances remained within 30 per cent of reference values under SANTE criteria.

Benefits and Practical Applications

Combining UPLC MS/MS and GC APGC MS/MS on a single instrument increases laboratory efficiency by reducing instrument downtime and method development efforts. The universal source architecture facilitates broad compound coverage without compromising sensitivity or data quality. This approach supports high throughput regulatory and in house testing with robust performance across diverse pesticide chemistries.

Future Trends and Potential Applications

Further enhancements may include integration with high resolution mass spectrometry for non targeted screening and expand to additional commodity classes. Automation of sample preparation and online extraction could streamline workflows. Continued evolution of ionization sources may improve the analysis of thermally labile or highly polar pesticides. Coupling with advanced data analytics will strengthen compliance monitoring and risk assessment strategies.

Conclusion

This work establishes a versatile, sensitive and reliable multi residue pesticide analysis method using UPLC and APGC technologies on a single mass spectrometer platform. The approach meets regulatory guidelines, delivers high throughput detection across matrices, and simplifies laboratory operations through unified instrumentation and method management.

Reference

1. D Shah, E McCall, G Cleland Single LC MS MS method for confirmation and quantification of over 400 pesticides in a complex matrix without compromising data quality Waters Application Note 720005559EN January 2016
2. T Kovalczuk et al UPLC MS MS a novel challenge in multiresidue pesticide analysis in food Analytica Chimica Acta 577 2006
3. M Tienstra et al Fast gas chromatographic residue analysis in animal feed using split injection and atmospheric pressure chemical ionisation tandem mass spectrometry Journal of Chromatography A 1422 2015
4. L Cherta et al Application of gas chromatography mass spectrometry with atmospheric pressure chemical ionisation for the determination of multiclass pesticides in fruits and vegetables Journal of Chromatography A 1314 2013
5. European Commission SANTE 11945 2015 Guidance document on analytical quality control and method validation procedures for pesticide residues analysis in food and feed 2015 revision 0