Innovation Development of Multidimensional Holographic Analysis Technology of the Multi-Mycotoxin in Pu’erTea Sample Analysis

Significance of the Topic

Mycotoxins are toxic secondary metabolites produced by fungi and frequently contaminate food products, including tea. Pu’er tea presents complex matrices that challenge conventional cleanup and detection methods. Developing an efficient, automated, and sensitive workflow for simultaneous determination of multiple mycotoxins addresses food safety, regulatory compliance, and operational efficiency in analytical laboratories.

Objectives and Study Overview

This study aimed to implement and validate a next-generation multidimensional liquid chromatography–tandem mass spectrometry (LC-MS/MS) platform, termed Multidimensional Holographic Analysis Technology (MHAT), for simultaneous analysis of 11 mycotoxins in Pu’er tea. Key goals included simplification of sample preparation, enhancement of separation selectivity, and full automation of data acquisition and quantitation.

Methodology and Instrumentation

The automated workflow integrates three main components:

• Multidimensional Extraction and Separation: A 1290 Infinity II UHPLC system coupled with an Agilent 6495C triple quadrupole MS. Two series-connected columns (Poroshell PFP and Phenyl-Hexyl) provide reversed-phase separation, while a trap system with a Poroshell HILIC-OH5 and SB-C8 cartridge enables heart-cutting and retention of polar analytes.
• Mobile Phases and Gradient Programs: A/B phases of 5 mM NH₄HCO₂H with 0.001 % formic acid in water and methanol for RP; 10 mM NH₄HCO₂H with 0.1 % formic acid in water and acetonitrile/water (90/10) for HILIC trapping. Flow rates at 0.3 mL/min and column temperature at 40 °C.
• Software and Data Processing: Agilent MassHunter Study Manager and automatic quantitation workflow employing dynamic MRM acquisition, automatic LOD/LOQ application, and template reporting for high-throughput results.

Key Results and Discussion

The MHAT system achieved lossless transfer and analysis of all 11 mycotoxins, including FB1 and FB2 in the HILIC dimension (2.5–5.5 min) and other toxins in RP separation (5.5–30 min). Matrix-matched calibration curves (1–100 ng/g) exhibited linearity with R² > 0.99 and precision below 20 %. Detection limits ranged between 1.0 and 2.0 ng/g. Recovery studies across different sample dilutions (1×, 2×, 10×) yielded 60–120 % recovery, meeting food safety regulation criteria.

Benefits and Practical Applications

• Streamlined sample preparation by simple solvent extraction and 10× dilution without immunoaffinity or QuEChERS cleanup.
• Significant time savings (>50 %) through automated multidimensional separation and data processing.
• High sensitivity and robustness enable routine multi-mycotoxin screening in tea and other complex food matrices.

Future Trends and Potential Applications

Further expansion to include over 50 mycotoxins is planned, leveraging MHAT’s scalability. Integration with machine-learning algorithms for automatic peak review and anomaly detection will enhance data reliability. The platform may also be adapted for other contaminants, such as pesticides and plant toxins, in diverse food and environmental samples.

Conclusion

The MHAT LC/TQ platform delivers a fully automated, sensitive, and versatile solution for multi-mycotoxin analysis in Pu’er tea. It achieves regulatory compliance with streamlined workflows, robust separation, and rapid data processing, representing a significant advance in food safety analytics.

Reference

1. Analysis of Mycotoxins in Food Matrices Using the Agilent Ultivo Triple Quadrupole LC/MS. Agilent Application Note: 5991-8962EN.
2. Rausch AK, Brockmeyer R, Schwerdtle T. Development, validation, and application of a multi-method for determination of mycotoxins, plant growth regulators, tropane alkaloids, and pesticides in cereals by two-dimensional LC-MS/MS. Anal Bioanal Chem. 2021;413:3041-3054.