A Multiresidue Method for Pesticide Analysis Using an Orbitrap Tribrid Mass Spectrometer and Automatic Background Exclusion

Importance of the Topic

Pesticide residues in food pose health risks to consumers and are tightly regulated worldwide. A multiresidue approach allows simultaneous detection of hundreds of compounds in a single run, enhancing efficiency and ensuring compliance with safety standards.

Study Objectives and Overview

The study aimed to develop and validate a comprehensive multiresidue method for quantifying 250 pesticides in food matrices using an Orbitrap ID-X Tribrid mass spectrometer. It also evaluated an automated background exclusion workflow (AcquireX) to boost untargeted screening performance at trace concentration levels.

Methodology and Instrumentation

Chromatographic separation was performed on a Vanquish UHPLC system with an Accucore aQ C18 column (100×2.1 mm, 2.6 μm), using a water/methanol gradient with ammonium formate and formic acid. Mass spectrometric analysis compared data‐dependent acquisition (DDA) and the AcquireX automated background exclusion workflow on the Orbitrap ID-X Tribrid instrument. Data processing for targeted quantification and library‐based screening was carried out in TraceFinder software utilizing the mzVault spectral library.

Used Instrumentation

• Thermo Scientific Vanquish UHPLC system
• Thermo Scientific Accucore aQ C18 column
• Thermo Scientific Orbitrap ID-X Tribrid mass spectrometer
• QuEChERS extraction kits for sample preparation
• Thermo Scientific TraceFinder software
• Thermo Scientific mzVault spectral library

Main Results and Discussion

The method achieved limits of detection (LOD) ≤1 ppb for 86% of analytes and limits of quantitation (LOQ) ≤1 ppb for 82%. Calibration curves displayed excellent linearity across 0.05–200 ppb. Reproducibility was high, with relative standard deviations below 10% at LOQ levels for 94% of the tested pesticides. The AcquireX workflow significantly increased the number of library‐matched pesticide identifications at low ppb levels compared with standard DDA, maintaining precision with %CV values within 5% for most compounds.

Benefits and Practical Applications of the Method

• High-throughput screening of hundreds of pesticides in a single 15-minute run
• Trace-level sensitivity suitable for regulatory compliance
• Enhanced untargeted screening via automated background exclusion, improving identification confidence
• Robust quantification with strong linearity, accuracy, and reproducibility for routine QA/QC

Future Trends and Potential Applications

Advancements in intelligent acquisition workflows, expanded spectral libraries, and machine learning algorithms are expected to further improve trace-level screening and reduce manual optimization. Integration of automated sample preparation and real-time data analysis will support high-throughput food safety monitoring and broader environmental applications.

Conclusion

The multiresidue method on the Orbitrap ID-X with AcquireX background exclusion provides sensitive, accurate, and reproducible quantitation of 250 pesticides. The automated workflow significantly enhances untargeted screening capabilities at low concentration levels, facilitating efficient and reliable food safety analysis.

Reference

Kalli A., Sharma S., Ghosh D. A Multiresidue Method for Pesticide Analysis Using an Orbitrap Tribrid Mass Spectrometer and Automatic Background Exclusion. Thermo Fisher Scientific, 2019.