122Contentsp1Analysis of Pesticides in Food Samples Using the SCIEXTriple QuadTM 3500 System

Significance of the Topic

Pesticide residues in food pose significant health risks and are tightly regulated worldwide. Advanced analytical methods are essential to ensure compliance with safety standards, protect consumers, and facilitate global trade. High-throughput, sensitive and robust screening technologies help laboratories monitor a wide range of pesticide compounds efficiently.

Study Objectives and Overview

This work evaluates an LC-MS/MS method for multiresidue pesticide analysis in fruits and vegetables using the SCIEX Triple Quad 3500 System. The goals include demonstrating improved sensitivity, reproducibility, and throughput compared to legacy platforms, and validating the approach against regulatory guidelines.

Methodology and Used Instrumentation

The approach employs a QuEChERS extraction based on the European standard EN 15662 using Phenomenex roQ kits for salt-based partitioning and dispersive SPE cleanup. Extracts are diluted five-fold in water and filtered through 0.45 µm PVDF Thomson filter vials before injection. Chromatographic separation is achieved on a Kinetex Biphenyl 2.6 µm (50 × 2.1 mm) column with a 0.5 mL/min gradient of water and methanol containing 5 mM ammonium formate. The SCIEX Triple Quad 3500 System is equipped with a Turbo V electrospray ionization (ESI) source operated at 400 °C. Approximately 400 positive-mode MRM transitions are scheduled using the Scheduled MRM Pro Algorithm, which optimizes dwell times, cycle times, and dynamic detection windows.

Main Results and Discussion

The new platform delivered an average three-fold sensitivity gain over the previous API 3200 System. Most pesticides achieved limits of detection below 1 ng/mL, with all compounds detectable at or below 2 ng/mL. Linearity spanned three to four orders of magnitude (r2 > 0.998), and repeatability at 1 and 10 ng/mL showed coefficients of variation below 10%. The Scheduled MRM Pro features, including flexible window widths, dynamic window extension, and MRM-triggered qualifier transitions, ensured comprehensive capture of peak profiles, even in cases of tailing at high concentrations.

Benefits and Practical Applications

• The combined QuEChERS-LC-MS/MS workflow enables rapid multiresidue screening of complex food matrices.
• High sensitivity and selectivity reduce sample preparation demands and matrix interferences.
• Automated scheduling and data processing in MultiQuant Software streamline quantitative and qualitative analysis, adhering to SANCO/12571/2013 criteria.
• The method supports routine QA/QC and regulatory compliance testing in food safety laboratories.

Future Trends and Possibilities

Emerging improvements may include integration of high-resolution mass spectrometry for non-targeted screening, miniaturized sample preparation to further reduce solvent use, and cloud-based data analytics for real-time monitoring across multiple laboratories. Enhanced spectral libraries and advanced machine-learning algorithms could expand compound coverage and predictive quality control.

Conclusion

The described LC-MS/MS method using the SCIEX Triple Quad 3500 System offers robust, sensitive, and high-throughput pesticide residue analysis in food samples. Its optimized extraction, chromatography, MRM scheduling, and data processing deliver reliable quantitation and identification, meeting stringent global food safety requirements.

Reference

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4. A. Schreiber et al. AB SCIEX Application Note #3370211-01 (2011)
5. CSN EN 15662 (2008)
6. SANCO/12571/2013 Guidance Document