Dilute and Shoot: A novel approach for determination of chlormequat and mepiquat in beer
DOI:
https://doi.org/10.18832/Keywords:
dilute and shoot, chlormequat, mepiquat, liquid chromatography, mass spectrometryAbstract
The extensive use of pesticides in agriculture has led to the presence of their residues in soil, water sources, and crops. Among these, the plant growth regulators chlormequat and mepiquat are commonly employed to regulate plant growth. The European Union has established maximum residue limits (MRLs) for different types of cereal (barley 7 mg/kg for chlormequat and 4 mg/kg for mepiquat). However, the extent to which these compounds are transferred from raw brewing materials into beer remains poorly understood, and no regulatory limits currently exist for their concentrations in beer. This study aimed to develop and validate a rapid, cost-effective, and straightforward analytical method for the simultaneous determination of chlormequat and mepiquat in beer. A Dilute and Shoot strategy was evaluated: degassed beer samples were diluted with acetonitrile and analysed using a Waters Acquity UPLC system coupled with a XEVO TQ-S micro mass spectrometer, including electrospray ionization (ESI). Chromatographic separation was achieved using an isocratic elution on a Kinetex® 1.7 μm (100 × 2.1 mm) HILIC column. Method performance was assessed in terms of linearity, detection and quantification limits, precision, and accuracy. Recoveries were 89% for chlormequat and 84% for mepiquat, with relative standard deviations (RSDs) not exceeding 4%. A total of 90 beer samples were analysed, revealing contamination in 86% of samples, with concentrations ranging from 0.1 to 28.9 μg/L.
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Copyright (c) 2026 Marek Pernica, Jan Martiník, Simona Černá, Zdeněk Svoboda, Karolína Benešová, Rastislav Boško, Sylvie Běláková
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