Abstract: Objective To rapidly screen a food poisoning incident,using ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry（UPLC-Q-TOF-MS） technology,laying an experimental foundation for the subsequent identification of tripterygium wilfordii toxin. Methods The ultrasonic-assisted methanol extraction method was used to extract toxins from tripterygium wilfordii plants in a poisoning incident that occurred in a city in Yunnan Province in May 2023. In the experiment,an ACQUITY UPLC^® BEH C₁₈ chromatographic column（2.1 mm×50 mm,1.7 μm） was selected to achieve effective separation of each component,and the column temperature was set at 40 ℃. A gradient elution method was applied with 0.1% aqueous formic acid as the aqueous phase and methanol as the organic phase,maintaining a flow rate of 0.3 mL/min and an injection volume of 2.0 μL. Results The linear correlation coefficients（r） of the nine target compounds were all >0.999 within the concentration range of 5.0-500 ng/mL,indicating a good linear relationship among the substances. At the same time,the relative standard deviation（RSD） of the intra-day precision was ≤3.9%,the RSD of inter-day stability was ≤6.9%,and the spiked recoveries rate was 99%-111%,demonstrating high precision and stability. Collect one remaining branch and leaf in the patient's home and one fresh branch and one dead branch in the field identified by the patient. Morphological identification showed that it was tripterygium wilfordii,and rapid screening of botanical specimens using UPLC-Q-TOF-MS detected triptolide in all samples. Conclusion This poisoning incident stems from the unintentional consumption of tripterygium wilfordii foliage,resulting in a foodborne poisoning case. The detection method is easy to operate,highly sensitive,precision,and efficient.

Key words: Ultra-performance liquid chromatography tandem quadrupole time-of-flight mass spectrometry, Tripterygium wilfordii, Poisoning