Nakamura Munetomo, Furumi Yasuko, Watanabe Fumiko, Mizukoshi Kazushi, Taniguchi Makoto, Nemoto Satoru
Japan Food Research Laboratories, Nagayama,Tama-shi, Tokyo.
Shokuhin Eiseigaku Zasshi. 2011;52(3):148-55. doi: 10.3358/shokueishi.52.148.
A simple and reliable liquid chromatographic-tandem mass spectrometric (LC-MS/MS) method was developed for carbendazim (MBC), thiophanate (TE), thiophanate-methyl (TM) and benomyl (BM) in agricultural products. These compounds were extracted from agricultural products with methanol after addition of sodium L-ascorbate. BM was hydrolyzed to MBC during the extraction with methanol. TE and TM were cyclized to ethyl 2-benzimidazole carbamate (EBC) and MBC by refluxing at 120 °C for 30 min with copper acetate in 50% acetic acid. MBC and EBC were cleaned up by an n-hexane wash and extraction with ethyl acetate and determined by LC-MS/MS. The mean recoveries from 10 agricultural products were in the range of 75.8-100.0%, and the relative standard deviations of 5 experiments were in the range of 1.5-9.2% at concentrations equal to the maximum residue limits (MRLs). The calibration curves were made by using commercial MBC and EBC as reference analytical standards without refluxing. The quantification limits were 0.01 mg/kg (as MBC), which is the uniform limit in the positive list system for agricultural chemical residues in foods in Japan.
建立了一种简单可靠的液相色谱 - 串联质谱法（LC-MS/MS），用于测定农产品中的多菌灵（MBC）、托布津（TE）、甲基托布津（TM）和苯菌灵（BM）。在添加L-抗坏血酸钠后，用甲醇从农产品中提取这些化合物。在甲醇提取过程中，BM水解为MBC。TE和TM在50%乙酸中与醋酸铜于120℃回流30分钟，环化为2-苯并咪唑氨基甲酸乙酯（EBC）和MBC。MBC和EBC经正己烷洗涤和乙酸乙酯萃取净化后，用LC-MS/MS测定。10种农产品的平均回收率在75.8 - 100.0%之间，在等于最大残留限量（MRLs）的浓度下，5次实验的相对标准偏差在1.5 - 9.2%之间。校准曲线采用市售MBC和EBC作为参考分析标准品制作，无需回流。定量限为0.01 mg/kg（以MBC计），这是日本食品中农业化学品残留肯定列表制度中的统一限量。
