Screening for Hundreds of Pesticide Residues Using a GC/Q-TOF with an Exact Mass Pesticide Database in Food

Importance of the Topic

Pesticide screening in food is critical for global food safety and regulatory compliance. The capacity to detect hundreds of residues at sub part per billion levels addresses growing demands from international trade and stringent guidelines such as the EU SANCO 12571.

Objectives and Study Overview

This application note demonstrates a high throughput workflow for simultaneous screening and quantification of over 700 pesticides in diverse food matrices using a gas chromatography quadrupole time of flight platform combined with an exact mass pesticide compound database. Food types include apple, carrot, leek, tomato and orange.

Methodology

• Sample extraction by a modified QuEChERS protocol with primary secondary amine sorbent clean up
• Chromatographic separation using midcolumn backflushing and retention time locking to enhance robustness and identification accuracy
• Electron ionization full spectral acquisition at five spectra per second
• Data analysis with a formula driven workflow to extract high specificity ions, apply retention time and coelution scoring for reliable compound confirmation

Used Instrumentation

• Agilent 7890B gas chromatograph with multimode inlet and HP 5MS Ultra Inert columns
• Agilent 7200 series GC QTOF mass spectrometer operated with electron ionization
• MassHunter software suite including Qualitative Analysis with All Ions workflow and Accurate Mass Pesticide PCDL, and Quantitative Analysis module

Main Results and Discussion

The method achieved detection of 56 representative pesticides at levels as low as 10 micrograms per kilogram across five food matrices. Coelution scoring and multiple fragment ion confirmation minimized false positives. Retrospective data interrogation was demonstrated, enabling quantification of unexpected compounds without reanalysis.

Benefits and Practical Applications

• High throughput screening and quantification in a single analysis
• Improved confidence in residue identification via accurate mass and coelution metrics
• Streamlined workflow from qualitative screening to targeted quantitative analysis
• Capability to handle complex matrices in routine monitoring and quality control

Future Trends and Potential Uses

The integration of accurate mass libraries with data independent acquisition is expected to expand to multiresidue methods in other matrices such as environmental and biological samples. Advances in software automation and spectral libraries will further reduce analysis time and enhance regulatory compliance capabilities.

Conclusion

The combined workflow of gas chromatography quadrupole time of flight with an exact mass pesticide database and advanced data processing delivers rapid, reliable screening and quantification of hundreds of pesticides at regulatory relevant levels in complex food matrices.

References

1. EU SANCO 12571 2013 Guidance on analytical quality control and validation procedures for pesticide residues analysis in food and feed
2. Retention Time Locking concepts and applications Agilent Technologies, 1997
3. Capillary Flow Technology with midcolumn backflush for matrix elimination Agilent Technologies, 2008
4. Comparison of multiresidue methods in green tea by chromatography tandem mass spectrometry Analyst, 2013
5. Spectral matching and peak purity in diode array detection High Performance Liquid Chromatography, 1993