Combination of GC/MS/MS and LC/MS/MS to Analyze Multiclass Pesticides in Orange Using One QuEChERS Sample Preparation Method

Significance of the Topic

In modern food safety control a reliable multiclass pesticide assay is crucial to monitor residues and protect public health. Oranges are susceptible to a wide range of pesticide applications. A streamlined approach that can detect hundreds of compounds helps laboratories meet regulatory requirements efficiently and cost effectively.

Objectives and Overview of the Study

The study set out to establish a single QuEChERS extraction protocol for orange samples and evaluate its compatibility with Agilent triple quadrupole instruments for both GCMSMS and LCMSMS. The goal was to cover over 450 pesticides and related metabolites listed in the Chinese national standard GB 2763 with high throughput and minimal method transfers.

Sample Preparation and Instrumentation

• Sample preparation followed a modified QuEChERS workflow using acetonitrile extraction, Agilent EN salt packet and dispersive SPE cleanup designed for fruits and vegetables.
• For LCMSMS analysis an Agilent Ultivo triple quadrupole was coupled to a 1260 Infinity Prime UHPLC with an Eclipse Plus C18 column and a water/methanol gradient with ammonium formate and formic acid modifiers.
• For GCMSMS analysis an Agilent 7000D GCMSMS was used with a dual column capillary setup, splitless injection and an HP 5ms column under a temperature gradient from 60 to 310 C.

Main Results and Discussion

Excellent chromatographic separation was observed for 326 compounds by LCMSMS and 293 compounds by GCMSMS at 10 ng per gram fortification. Method accuracy measured by recovery at 10 to 50 µg per kilogram spiked levels showed that 90 percent of analytes fell between 70 and 120 percent recovery. Precision tests yielded relative standard deviations below ten percent for more than 90 percent of compounds on both platforms.

Benefits and Practical Applications

• High throughput screening of over 450 pesticides using a single sample preparation workflow
• Time and cost savings by combining GC and LC analyses in parallel
• Reliable compliance with stringent national residue limits
• Scalability for routine analysis in government and commercial laboratories

Future Trends and Potential Applications

Integration of automated sample handling and data processing will further improve laboratory efficiency. Expanding the method to other fruit matrices and emerging pesticide classes may support broader monitoring needs. Advances in high resolution MS could complement the current approach for non targeted screening.

Conclusion

The combination of a unified QuEChERS extraction with Agilent 7000D GCMSMS and Ultivo LCMSMS delivers accurate, precise and comprehensive analysis of multiclass pesticides in orange. This workflow meets the demands of routine residue monitoring and regulatory compliance with minimal instrument methods adjustments.

References

• GB 2763 2016 National food safety standard Maximum residue limits for pesticides in food