Simultaneous determination of pesticides, mycotoxins, tropane alkaloids, growth regulators, and pyrrolizidine alkaloids in oats and whole wheat grains after online clean-up via two-dimensional liquid chromatography tandem mass spectrometry

Abstract

In this study, a two-dimensional liquid chromatography tandem mass spectrometry method was developed and validated for the determination of pesticide residues and contaminants in whole wheat grains and oats. The samples were extracted with a mixture of acetonitrile and water and were injected into the two-dimensional LC-MS/MS system without any further clean-up or sample preparation. Samples were analyzed with four different matrix matched calibrations. Matrix effects were evaluated by comparing analyte signals in the respective matrix matched standard with the neat solvent standards. The final method was validated according to the current Eurachem validation guide and SANTE document. The number of successfully validated analytes throughout all three validation levels in oats and wheat, respectively, were as follows: 330 and 316 out of 370 pesticides, 6 and 13 out of 18 pyrrolizidine alkaloids and 7 out of 9 regulated mycotoxins. Moreover, both plant growth regulators mepiquat and chlormequat as well as the tropane alkaloids atropine and scopolamine met the validation criteria. The majority of pesticides showed limits of detection below 1 µg kg⁻¹, pyrrolizidine alkaloids below 0.7 µg kg⁻¹, tropane alkaloids below 0.2 µg kg⁻¹, growth regulators below 0.7 µg kg⁻¹ and mycotoxins below 8 µg kg⁻¹ in both matrices.

KEYWORDS:

• Mycotoxins
• plant growth regulators
• pyrrolizidine alkaloids
• tropane alkaloids
• two-dimensional liquid chromatography tandem mass spectrometry

Acknowledgments

This research was supported by the LVA GmbH and the Department of Chemistry, Boku Vienna. Special thanks to Celine Lesueur, Barbara Schwaiger, David Steiner and Andreas Gschaider for their support.

Disclosure statement

Michael Urban, Stephan Hann and Helmut Rost declare that they have no conflict of interest.

Ethical approval

This article does not contain any studies with human participants or animals performed by any of the authors.

Informed consent

Not applicable.

Additional information

Funding

This study was funded by the LVA GmbH, 3400 Klosterneuburg.