建立了超高效液相色谱-串联质谱法（UHPLC-MS/MS）测定水果、蔬菜、茶叶等植物源性食品中丁氟螨酯及其代谢物邻三氟甲基苯甲酸含量的方法。在样品4 g （茶叶1 g）中加入90%（体积分数）乙腈溶液10 mL、1 mol·L^-1盐酸溶液1.0 mL、无水硫酸钠3 g和氯化钠2 g，振荡提取2 min后，离心，取上层乙腈相注入石墨化碳黑固相萃取小柱中净化，再用6 mL体积比为2：3的丙酮-甲醇的混合液洗脱，收集流出液和洗脱液，于40℃氮吹至近干，加入2 mL 40%（体积分数）乙腈溶液，过滤，取滤液进行UHPLC-MS/MS测定。以Waters ACQUITY UPLC BEH C₁₈柱为固定相，以不同体积比的乙腈-含0.2%（体积分数）甲酸的5 mmol·L^-1乙酸铵溶液的混合液为流动相对其进行梯度洗脱。质谱分析采用电喷雾正、负离子源（ESI⁺、ESI^-）和多反应监测（MRM）模式，以基质匹配的混合标准溶液系列绘制工作曲线。结果显示：在大豆、茄子、甘蓝、西红柿、苹果、绿茶中，丁氟螨酯和邻三氟甲基苯甲酸的质量浓度在10~500 μg·L^-1内与其对应的峰面积呈线性关系，丁氟螨酯和邻三氟甲基苯甲酸的检出限（3S/N）为0.1~2.9 μg·kg^-1；按标准加入法对上述阴性样品进行加标回收试验，丁氟螨酯及邻三氟甲基苯甲酸的回收率为78.2%~93.0%，测定值的相对标准偏差（RSD，n=10）为2.8%~14%，再现性RSD （n=5）不大于15%。

A method for determination of cyflumetofen and its metabolite o-trifluoromethyl benzoic acid in plant origin food (such as fruit, vegetable, tea) by UHPLC-MS/MS was established. 4 g of sample (1 g of tea sample) was extracted by oscillation in a mixture of 10 mL of 90% (φ) acetonitrile solution, 1.0 mL of 1 mol·L^-1 hydrochloric acid solution, 3 g of anhydrous sodium sulfate and 2 g of sodium chloride for 2 min. After centrifuging, the upper acetonitrile phase was injected into graphitized carbon black solid phase extraction small column for purification, and 6 mL of a mixture of acetone and methanol at volume ratio of 2:3 was used for elution. The effluent and eluent were collected and blown to nearly dry by nitrogen, and 2 mL of 40% (φ) acetonitrile solution was added. After filtering, the filtrate was introduced into UHPLC-MS/MS for determination. Waters ACQUITY UPLC BEH C₁₈ column was used as stationary phase, and a mixture of acetonitrile and 5 mmol·L^-1 ammonium acetate solution containing 0.2% (φ) formic acid with different volume ratios was used as the mobile phase for gradient elution. ESI⁺, ESI^- and MRM mode were adopted in MS/MS analysis. The working curves were drawn with the matrix matching of mixed standard solution series. It was showed that linear relationships between mass concentrations of cyflumetofen and o-trifluoromethyl benzoic acid and their peak areas were kept in the range of 10-500 μg·L^-1 for sample of soybean, eggplant, cabbage, tomato, apple and green tea, with detection limits (3S/N) in the range of 0.1-2.9 μg·kg^-1. Recovery test was made on above negative samples by standard addition method, giving results of cyflumetofen and o-trifluoromethyl benzoic acid in the range of 78.2%-93.0%. RSDs (n=10) of the determined values were ranged from 2.8% to 14%, and RSDs of reproducibility (n=5) were less than 15%.