Zhang Changpeng, Zhao Hua, Wu Min, Hu Xiuqing, Cai Xiaoming, Ping Lifeng, Li Zhen
State Key Lab Breeding Base for Zhejiang Sustainable Plant Pest Control, Institute of Quality and Standard for Agro-Products, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
J Chromatogr Sci. 2012 Nov-Dec;50(10):940-4. doi: 10.1093/chromsci/bms094. Epub 2012 Jun 11.
A sensitive and effective method for the simultaneous quantitative determination of procymidone, pyridaben and beta-cypermethrin residues in tea solutions was developed and validated using a gas chromatograph (GC) equipped with an electron capture detector (ECD). The analysis of the three pesticides in tea solutions involved extraction with petroleum ether-ethyl acetate (3:1, v/v), cleanup using a Florisil solid-phase extraction cartridge and subsequent determination by GC-ECD. Recovery studies were carried out at three spiked levels (0.05, 0.1 and 0.5 mg/kg). The overall average recoveries using this method in green teas and black teas at the three concentration levels ranged from 85.63 to 105.80% with relative standard deviations in the range of 1.29-4.97% (n = 5) for all analytes. The quantification limits of procymidone, pyridaben and beta-cypermethrin were 0.025, 0.038 and 0.030 mg/kg, respectively, which were lower than the maximum residue limits (MRLs) of 0.1 mg/kg procymidone, 0.05 mg/kg pyridaben and 0.5 mg/kg beta-cypermethrin in tea samples established by European Union legislations. This study provides a theoretical basis for China to draw up MRLs for procymidone, pyridaben and beta-cypermethrin in tea solutions.
建立了一种灵敏有效的方法，用于同时定量测定茶溶液中腐霉利、哒螨灵和高效氯氰菊酯的残留量，并使用配备电子捕获检测器（ECD）的气相色谱仪（GC）进行了验证。茶溶液中三种农药的分析包括用石油醚 - 乙酸乙酯（3:1，v/v）萃取、使用弗罗里硅土固相萃取柱净化以及随后通过GC - ECD进行测定。在三个加标水平（0.05、0.1和0.5 mg/kg）下进行了回收率研究。使用该方法在绿茶和红茶中三个浓度水平下的总体平均回收率为85.63%至105.80%，所有分析物的相对标准偏差在1.29 - 4.97%范围内（n = 5）。腐霉利、哒螨灵和高效氯氰菊酯的定量限分别为0.025、0.038和0.030 mg/kg，低于欧盟法规规定的茶叶样品中腐霉利0.1 mg/kg、哒螨灵0.05 mg/kg和高效氯氰菊酯0.5 mg/kg的最大残留限量（MRLs）。本研究为中国制定茶溶液中腐霉利、哒螨灵和高效氯氰菊酯的MRLs提供了理论依据。
