Determination of Multiple Mycotoxins in Grain Using a QuEChERS Sample Preparation Approach and LC-MS/MS Detection

Importance of the Topic

The presence of mycotoxins in grain-based foods poses significant health risks due to their stability during processing and potent toxic effects even at low levels. International food safety regulations demand reliable, multi-residue analytical methods to monitor contamination and protect public health.

Objectives and Study Overview

This study aimed to establish a rapid, cost-effective QuEChERS-based workflow combined with LC-MS/MS for simultaneously quantifying 16 key mycotoxins in cereal products. The method leverages a Thermo Scientific Accucore aQ column and a TSQ Vantage triple quadrupole mass spectrometer for high-throughput analysis.

Methodology and Sample Preparation

• Sample extraction: 5 g of homogenized cereal is hydrated, spiked with internal standards (3-Acetyldeoxynivalenol-D3, thiabendazole-13C6, gemfibrozil-D6), and extracted with acetonitrile containing 2 % formic acid using unbuffered QuEChERS salts.
• Cleanup: Dispersive SPE (PSA/C18) removes polar interferences and lipids; extracts are evaporated, reconstituted in 50:50 methanol/water, and filtered through 0.2 µm nylon.
• Calibration: Five-point matrix-matched curves (10–200 µg/kg) ensure accuracy over the regulatory range.

Used Instrumentation

• UHPLC: Thermo Scientific Dionex UltiMate 3000 with Accucore aQ column (100 × 2.1 mm, 2.6 µm) at 45 °C, 400 µL/min flow.
• MS/MS: Thermo Scientific TSQ Vantage with APCI+ and APCI− fast polarity switching; selected reaction monitoring for all analytes.

Main Results and Discussion

The optimized gradient achieved baseline separation of all 16 mycotoxins, including α- and β-zearalanol, within 13 minutes. Methanol-based mobile phase with 10 mM ammonium formate improved retention and peak shape, while strategic waste diversion minimized matrix effects. Limits of quantitation were ≤ 10 µg/kg for all analytes. Linearity was excellent (R2 > 0.995), recoveries ranged from 80 to 110 % (nivalenol ~70 %), and precision (RSD) was ≤ 11 % across fortified levels.

Benefits and Practical Applications

• High-throughput analysis with short run times and minimal instrument downtime.
• Comprehensive multi-residue coverage suitable for routine QA/QC and regulatory testing.
• Robust performance across diverse cereal matrices.

Future Trends and Potential Applications

Emerging developments include automated QuEChERS platforms, high-resolution accurate-mass spectrometry for non-target screening, and machine-learning algorithms for data interpretation. Miniaturized extraction techniques and integrated on-line cleanup promise further improvements in speed and sustainability.

Conclusion

The presented QuEChERS–LC-MS/MS protocol offers a rapid, sensitive, and reliable solution for monitoring multiple mycotoxins in grain-based foods. Its simplicity and high performance make it an attractive tool for food safety laboratories.

References

• FAO Manual on the Application of the HACCP System in Mycotoxin Prevention and Control.
• Gremmels J. Veterinary Quarterly, 1999, 21, 115–120.
• Lattanzio V.; Pascale M.; Visconti A. Trends Anal Chem, 2009, 28, 758–768.
• Pereira V.; Fernandes J.; Cunha S. Trends Food Sci Technol, 2014, 36, 96–136.
• Köppen R. et al. Appl Microbiol Biotechnol, 2010, 86, 1595–1612.
• Zöllner P.; Mayer-Helm B. J Chromatogr A, 2006, 1136, 123–169.
• Hajslova J.; Zachariasova M.; Cajka T. Mass Spectrom Food Safety Methods Protocols, 2011, 747, 233–258.
• Desmarchelier A. et al. J Agric Food Chem, 2010, 58, 7510–7519.
• Rubert J. et al. Talanta, 2012, 99, 712–719.
• Bolechova M. et al. Food Control, 2015, 47, 108–113.
• Koesukwiwat U.; Sanguankaew K.; Leepipatpiboon N. Food Chem, 2014, 153, 44–51.