Qin Meiling, Chai Shuangshuang, Ma Youning, Gao Huanhuan, Zhang Hantong, He Qiao
Rice Product Quality Inspection and Supervision Center, Ministry of Agriculture, Laboratory of Quality and Safety Risk Assessment for Rice, Ministry of Agriculture, China National Rice Research Institute, Hangzhou 310006, China.
Se Pu. 2017 Jul 8;35(7):719-723. doi: 10.3724/SP.J.1123.2017.02032.
A method was developed for the determination of pyriminobac-methyl and bispyribac-sodium residues in rice by liquid chromatography-tandem mass spectrometry (LC-MS/MS) coupled with modified QuEChERS. The samples were extracted with acidified acetonitrile, and then purified by octadecylsilane bonded silica (C) adsorbents. The analytes were separated on a ZORBAX SB C column through a gradient elution using 0.1% (v/v) aqueous formic acid aqueous containing 5 mmol/L ammonium acetate and acetonitrile as mobile phases. Positive electrospray ionization (ESI) was used. Qualitative work was performed using selected dynamic multiple reaction monitoring (dynamic MRM) mode. Quantization was performed using external standard method. The results showed good linearities of pyriminobac-methyl and bispyribac-sodium with correlation coefficients () not less than 0.996. The limits of detection (LODs) of the method were 0.8 μ g/kg for pyriminobac-methyl, and 3 μ g/kg for bispyribac-sodium. The mean spiked recoveries of pyriminobac-methyl and bispyribac-sodium at three spiked levels were 76.6%-85.6% and 73.0%-86.7%, respectively, and the relative standard deviations (RSDs) of pyriminobac-methyl and bispyribac-sodium were 0.9%-3.4% and 1.2%-5.5%, respectively. This method is simple, rapid, sensitive, and suitable for the simultaneous determination of pyriminobac-methyl and bispyribac-sodium in rice.
建立了一种液相色谱-串联质谱法（LC-MS/MS）结合改进的QuEChERS方法，用于测定大米中嘧草醚和双草醚钠残留量。样品用酸化乙腈提取，然后用十八烷基硅烷键合硅胶（C）吸附剂净化。分析物在ZORBAX SB C柱上分离，采用0.1%（v/v）含5 mmol/L醋酸铵的甲酸水溶液和乙腈作为流动相进行梯度洗脱。采用正电喷雾电离（ESI）。定性分析采用选择动态多反应监测（动态MRM）模式。定量分析采用外标法。结果表明，嘧草醚和双草醚钠具有良好的线性关系，相关系数（）不小于0.996。该方法对嘧草醚的检出限（LOD）为0.8μg/kg，对双草醚钠的检出限为3μg/kg。嘧草醚和双草醚钠在三个加标水平下的平均加标回收率分别为76.6%-85.6%和73.0%-86.7%，嘧草醚和双草醚钠的相对标准偏差（RSD）分别为0.9%-3.4%和1.2%-5.5%。该方法简便、快速、灵敏，适用于大米中嘧草醚和双草醚钠的同时测定。
