Quantitative analysis of mycotoxins in wheat and feed using high-resolution Q Exactive Focus

introduction

Mycotoxins are metabolites produced by fungi growing in food or feed, and have great health risks to humans and animals
.
According to the statistics of the Food and Agriculture Organization of the United Nations ( FAO ), about 25% of


global agricultural products are contaminated with mycotoxins each year .
In order to ensure the safety of food and feed, many countries around the world have adopted regulations or standards to strictly regulate the limits of major mycotoxins in food .
However, traditional detection methods have problems such as long time-consuming, low throughput, and poor qualitative ability .
In this paper, a high-resolution desktop mass spectrometer Q Exactive Focus was used to establish a detection method for a variety of mycotoxins in food extracts
.
The method has a sensitivity comparable to high-end triple quadrupoles, and can accurately qualitatively analyze trace substances in complex matrices, fully guaranteeing the accuracy of the results
.

Experimental method Liquid chromatography method

UHPLC : Thermo Scientific RSLC Ultimate 3000 Column: Thermo Scientific a Hypersil Gold (50 * 2.
1mm , 1.
9 [mu] m ) flow rate: 0.
3 mL / min , injection volume: .
5 [mu] L Mobile Phase: A Phase: 2mM ammonium formate and 20 µ L/L formic acid aqueous solution phaseB : 2mM ammonium formate and 20 µ L/L formic acid methanol solution

Gradient elution:

Time (min) %A %B

0 982

2 55 45

6 298

11 298

11.
5 98 2
14 982

Mass spectrometry method

Mass spectrometer: Thermo Scientific Q Exactive Focus desktop high resolution mass spectrometer

Sample preparation method

The sample preparation method refers to the literature [1] , the sample is leached in 1% formic acid acetonitrile / water solution for 15 minutes , shaken for 1 hour , centrifuged, filtered, and analyzed
.

Experiment and Discussion Screening Results Analysis

Under a certain Mass tolerance , the exact mass of the compound adduct ion peak is extracted from the data of Fullscan , and the XIC spectrum is
obtained .
Q Exactive Focus has good quality accuracy, so the extraction window can be reduced to 5ppm or even lower, which fully guarantees the extremely high selectivity of the method
.
At the same time, Q Exactive Focus can achieve fast positive and negative ion switching scanning, and ensure high-quality accuracy in the positive and negative switching mode, which improves the throughput of the screening experiment while ensuring the accuracy of the results (Figure 3 )
.

Quantitative result analysis

This article uses Full MS-ddMS ² and t-SIM-ddMS ² for quantitative analysis

Figure 3.

While collecting the first-level scan data in the experiment, the inclusion list in the method settings can also trigger the data-dependent scan to obtain the full scan spectrum of the second-level product ions, and use this to confirm the results

in conclusion

This paper established a method for screening and quantifying mycotoxins in food by using high-resolution mass spectrometry