Strategies for the Screening and Identification of Mycotoxins in Food by UHPLC/Q-TOF/MS

Significance of the Topic

Mycotoxins are toxic secondary metabolites produced by certain fungi that frequently contaminate foodstuffs and pose serious risks to human and animal health. Rapid and reliable screening methods are essential for ensuring food safety, complying with regulatory limits, and preventing economic losses in the food industry.

Objectives and Study Overview

The primary aim of this work was to develop and demonstrate a comprehensive screening and identification strategy for a broad range of mycotoxins in various food matrices using ultra-high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC/Q-TOF/MS). The study focused on both targeted and non-targeted workflows to detect known mycotoxins and discover unexpected analogues or conjugates.

Methodology and Instrumentation

A generic sample preparation protocol based on solvent extraction and minimal cleanup was applied to cereals, oils, and processed foods. Chromatographic separation employed a reversed-phase UHPLC column with a gradient of water and acetonitrile, each containing 0.1% formic acid, achieving sharp peak shapes and retention of polar and nonpolar toxins.
Used instrumentation:

• UHPLC system with binary high-pressure pump and temperature-controlled autosampler
• Electrospray ionization source operated in positive and negative modes
• Quadrupole time-of-flight mass analyzer providing high-resolution full-scan accurate-mass spectra
• Automated data acquisition software for simultaneous MS and MS/MS experiments

Main Results and Discussion

High-resolution full-scan data enabled the detection of over 50 mycotoxin parent compounds and modified forms in a single run. Accurate mass measurements (mass errors < 5 ppm) combined with isotopic pattern matching allowed confident elemental composition assignment. Targeted MS/MS spectra libraries facilitated rapid confirmation of known toxins, while a suspect screening workflow based on predicted formulas uncovered several masked metabolites.
Key findings:

• Detection limits in the low µg/kg range for major mycotoxins (e.g., aflatoxins, ochratoxin A, fumonisins)
• Identification of phase II conjugates (glucosides and sulfates) not covered by routine methods
• High throughput: analysis time of 10 minutes per sample

Benefits and Practical Applications

The described UHPLC/Q-TOF/MS approach delivers:

• Comprehensive coverage of regulated and emerging mycotoxins
• Enhanced selectivity and sensitivity through accurate-mass screening
• Flexibility to add new targets or suspect lists without revalidation
• Reduced false positives via high-resolution MS/MS confirmation

This strategy is well suited for food safety laboratories, regulatory agencies, and research centers performing routine monitoring and extended surveys.

Future Trends and Applications

Advances in software for automated feature extraction and machine learning–based annotation will further streamline non-targeted screenings. Integration of ion mobility separation promises additional selectivity for isomeric mycotoxins. Expanding high-resolution screening databases to include more conjugated and novel toxins will improve early warning capabilities. Coupling with bioinformatics tools may enable risk prediction based on toxin profiles.

Conclusion

The presented UHPLC/Q-TOF/MS workflows offer a powerful platform for the rapid, sensitive, and comprehensive screening of mycotoxins in food. By combining full-scan accurate-mass detection with targeted and suspect screening, laboratories can achieve broad analyte coverage and reliable identification, supporting robust food safety management.