Simultaneous Determination of Pesticide Residues in Vegetable Extract by LC/MS/MS [LCMS™-8050]

Significance of the Topic

Monitoring pesticide residues ensures food safety and compliance with regulatory limits. Analytical methods must overcome matrix interferences while providing high sensitivity at trace levels. The approach presented here combines efficient sample preparation with streamlined calibration to support routine quality control and environmental monitoring.

Aim and Study Overview

This work outlines a liquid chromatography–tandem mass spectrometry (LC–MS/MS) method for simultaneous determination of 89 pesticides in carrot extract. The primary goal is to achieve high recovery accuracy and reproducibility using an absolute calibration protocol, thereby avoiding the need for matrix-matched standards for each sample.

Materials and Methods

Carrot extracts were prepared using a QuEChERS-based solid-phase extraction. Calibration standards ranged from 0.1 to 50 ng/mL and were analyzed via absolute calibration. Chromatographic separation employed a Shim-pack Scepter C18 column with a gradient from 3 % to 100 % methanolic ammonium acetate over a 32 min run.

Instrumentation

• UHPLC system: Nexera X2
• Mass spectrometer: LCMS-8050 triple quadrupole
• Ionization mode: Electrospray in positive/negative switch
• Key settings: DL temperature 150 °C, interface 200 °C, block heater 500 °C; nebulizer gas 2 L/min; drying/heating gas 10 L/min

Results and Discussion

Spike-and-recovery tests at 1 ng/mL demonstrated that 82 out of 89 pesticides achieved recoveries between 70 % and 120 %. Seventy compounds also exhibited reproducibility with relative standard deviations below 3 % over ten replicates. Calibration curves showed excellent linearity across the tested range. Representative MRM chromatograms confirmed sharp peak shapes and consistent response factors for low-level quantification.

Practical Benefits and Applications

This method simplifies routine pesticide screening by eliminating the need for matrix-matched calibration curves for each sample type. The absolute calibration approach reduces validation complexity and supports high-throughput analysis in food safety, environmental surveillance, and quality assurance laboratories.

Future Trends and Opportunities

• Adaptation of the protocol to diverse crop and environmental matrices
• Integration with high-resolution MS for broad-spectrum screening
• Automation of sample preparation and data processing pipelines
• Development of greener extraction solvents and miniaturized formats

Conclusion

The LCMS-8050 triple quadrupole method, combined with Nexera X2 UHPLC and absolute calibration, delivers robust quantification of 89 pesticides in vegetable extracts. High recovery rates and reproducibility validate its application for reliable residue analysis.

Reference

N. Maeshima, Application Note No. C208, Shimadzu Corporation, 2020.