UPLC and APGC Multi Residue Pesticide Analysis on a Single Tandem Quadrupole Mass Spectrometer Platform

Significance of the topic

Ensuring the safety of fresh produce requires robust multi-residue pesticide analysis capable of detecting hundreds of compounds at low levels. Regulatory bodies set maximum residue limits (MRLs) to protect consumers, and laboratories need efficient, sensitive workflows to enforce these limits. Combining liquid and gas chromatography with tandem mass spectrometry on a single platform simplifies operations and enhances throughput while maintaining high analytical performance.

Objectives and Study Overview

This work demonstrates a unified workflow for the analysis of a broad suite of pesticides in fruit and vegetable matrices using a single Xevo TQ-S micro tandem quadrupole mass spectrometer. The study covers both ultra-performance liquid chromatography (UPLC–MS/MS) and atmospheric pressure gas chromatography (APGC–MS/MS) on the same instrument, targeting legislatively relevant levels down to 0.010 mg/kg in various matrices.

Methodology and Instrumentation

Sample Preparation and Cleanup

• QuEChERS AOAC 2007.01 extraction using DisQuE kits
• Matrices: celery, lemon, corn, kale to represent diverse water, acid, starch, and pigment content
• dSPE cleanup with MgSO4, PSA and GCB sorbents as appropriate for each matrix

Instrument Configuration

• Xevo TQ-S micro tandem quadrupole MS with universal source
• UPLC inlet: ACQUITY UPLC H-Class, BEH C18 column, ESI+ mode
• APGC inlet: Atmospheric pressure GC source, Rxi-5MS column, proton transfer ionization
• Quanpedia database for automated MRM method generation
• TargetLynx XS for data processing and quantification

Main Results and Discussion

Method Management

• Quanpedia enabled rapid method updates and MRM scheduling for ~200 compounds per inlet

Data Acquisition Performance

• Fast scan speeds (<6 ms dwell time) supported >12 data points per peak in busy segments
• Retention time windows of 1 min (UPLC) and 30 s (GC) accommodated shifts without data loss

Analytical Figures of Merit

• Linearity: R² ≥0.995 for most analytes (linear for UPLC, quadratic for APGC)
• Sensitivity: detection at default MRL of 0.010 mg/kg for >99% of pesticides
• Precision: >90% of compounds showed peak area RSD ≤10% in celery, lemon, corn; >80% in kale

Benefits and Practical Applications

• Single-instrument flexibility reduces footprint and method transfer complexity
• Automated method generation minimizes setup time and risk of manual errors
• Compliance with SANTE 11945/2015 ensures data quality for regulatory testing
• QuEChERS extraction delivers rapid, cost-effective sample preparation

Future Trends and Potential Applications

Emerging developments include expanded compound libraries, integration with high-resolution MS for unknown screening, and further automation in data processing. Soft ionization techniques like APGC may be extended to other labile analytes, while cloud-based method management could streamline multi-site operations.

Conclusion

This study confirms that UPLC-MS/MS and APGC-MS/MS can be seamlessly integrated on a single Xevo TQ-S micro platform to deliver sensitive, precise multi-residue pesticide analysis. Automated workflows using Quanpedia and TargetLynx enhance laboratory efficiency and ensure compliance with stringent regulatory standards.

References

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4. L Cherta et al., J. Chromatogr. A 1314, 2013
5. European Commission SANTE/11945/2015 Guidance Document, 2015
6. AOAC Official Method 2007.01, 2013