Wang Fengen, Ding Min, Zhang Chao, Li Ruiju, Ma Cuihua, Li Xia, Li Zengmei, Li Huidong, Zhang Hong, Yan Mengmeng, Deng Ligang
Institute of Quality Standard and Testing Technology for Agro-Products, Shandong Academy of Agricultural Sciences, Jinan 250100, China.
Boxing County Comprehensive Inspection and Testing Center, Binzhou 256500, China.
Foods. 2025 Jun 20;14(13):2153. doi: 10.3390/foods14132153.
Chlorothalonil and its toxic metabolite, 4-hydroxy-chlorothalonil, pose significant environmental and health risks. However, their simultaneous and accurate detection remains challenging due to their differing ionization efficiencies in mass spectrometry and the interference caused by enzymatic reactions in sulfur-rich vegetables. This study developed a UHPLC-MS/MS method for simultaneous detection of chlorothalonil and 4-hydroxy-chlorothalonil, using an atmospheric pressure chemical ionization (APCI) source, optimizing the probe temperature to 600 °C and a set of optimal chromatography parameters. A low-temperature and acidification synergistic enzyme inhibition strategy was developed, involving refrigerating samples and extraction reagents, acidifying with citric acid before sample homogenization, and extracting with formic acid/acetonitrile, significantly improving chlorothalonil recovery. Method validation demonstrated limits of detection (LOD) and quantification (LOQ) of 0.003 mg/kg and 0.01 mg/kg, respectively, with recoveries of 76.5-91.1% for chlorothalonil and 87.6-96.7% for 4-hydroxy-chlorothalonil. The method was successfully applied in monitoring the residue risks in sulfur-rich vegetables.
百菌清及其有毒代谢物4-羟基百菌清对环境和健康构成重大风险。然而，由于它们在质谱分析中的电离效率不同以及富含硫的蔬菜中酶促反应造成的干扰，同时准确检测它们仍然具有挑战性。本研究开发了一种超高效液相色谱-串联质谱法（UHPLC-MS/MS），用于同时检测百菌清和4-羟基百菌清，采用大气压化学电离（APCI）源，将探针温度优化至600℃并设置了一组最佳色谱参数。开发了一种低温酸化协同酶抑制策略，包括将样品和提取试剂冷藏，在样品匀浆前用柠檬酸酸化，并用甲酸/乙腈提取，显著提高了百菌清的回收率。方法验证表明，检测限（LOD）和定量限（LOQ）分别为0.003 mg/kg和0.01 mg/kg，百菌清的回收率为76.5-91.1%，4-羟基百菌清的回收率为87.6-96.7%。该方法成功应用于监测富含硫的蔬菜中的残留风险。
