Rapid Screening and Determination of 20 Plant-Derived Toxins in Honey by UPLC-Q-Exactive Quadrupole-Electrostatic Field Track Trap High Resolution Mass Spectrometry

In this study, the method was applied in the rapid screening and determination of 20 plant-derived toxins in honey by ultra-performance liquid chromatography-tandem Q-Exactive quadrupole-electrostatic field track trap high resolution mass spectrometry (UPLC-Q-Exactive). According to precise molecular weight of compounds and multistage fragment ion information detected by UPLC-Q-Exactive, an in-house database of 20 plant-derived toxins was established. The sample was extracted by pure water, and purified on a mixed-mode polymeric strong cation exchange and reversed-phase column (MCX). The extract was separated on an AQ-C₁₈ column (2.1 mm×100 mm, 1.9 μm) through a mobile phase composition of acetonitrile and water (containing 0.1% formic acid and 10 mmol/L ammonium formate) in gradient elution mode. The high resolution mass spectrometry data was simultaneously acquired in full scan data-dependent MS/MS acquisition mode(Full MS/ddMS²), and external standard calibration curves were used for quantification. Results and conclusions were drawn as follows. First, desirable linearities of 20 plant-derived toxins were evaluated among the peak area responses and concentrations in the range of 10.0 to 200.0 μg/L, and the correlative coefficients were over 0.99. The limits of detection were 0.4~6.9 μg/kg. The average recoveries of all the toxins were 74.1%~114.6% at three different levels, and the relative standard deviations (RSDs) ranged between 0.2%~4.7%. This method is sensitive, accurate, reliable and easy to operate, which can be used for rapid screening and quantitative analysis of the 20 plant- derived toxins in honey.