Attallah Emad R, Soliman Mostafa, Abo-Aly Mohamed M
Ministry of Agricultureand Land Reclamation, Agricultural Research Center, Central Laboratory of Residue Analysis of Pesticides and Heavy Metals in Foods, 7-Nadi Elsaid St, Dokki, Giza, Egypt.
Ain Shams University, Faculty of Science, Chemistry Department, Cairo, Egypt.
J AOAC Int. 2017 May 1;100(3):789-795. doi: 10.5740/jaoacint.16-0315. Epub 2017 Feb 2.
A simple, modified quick, easy, cheap, effective, rugged, and safe procedure was developed for the determination of diquat in potato using reversed-phase LC coupled with tandem MS (MS/MS) in a total run time of 10 min. Different sample preparation parameters (pH modifier type, sample size, and elevated temperature) were tested and optimized. Potato sample was extracted with acetonitrile in the presence of ammonium hydroxide at 80°C. Phase separation was obtained by shaking the extract with magnesium sulfate and sodium chloride, and analysis was done using LC-MS/MS. Matrix-matched standard calculations were used to compensate for matrix-induced suppression in LC-MS/MS determination. The precision and trueness of the method were determined from recovery experiments on five replicates of spiked blank potato samples at 0.01, 0.05, and 0.1 mg/kg. The range of the obtained recoveries was 74-110%, with RSD values <5% for all the concentrations.
开发了一种简单、改良的快速、简易、廉价、有效、耐用且安全的方法，用于在10分钟的总运行时间内，使用反相液相色谱-串联质谱（MS/MS）测定马铃薯中的敌草快。测试并优化了不同的样品制备参数（pH调节剂类型、样品量和升高的温度）。马铃薯样品在80°C下于氢氧化铵存在的情况下用乙腈萃取。通过将萃取液与硫酸镁和氯化钠振荡实现相分离，并使用液相色谱-串联质谱进行分析。在液相色谱-串联质谱测定中，采用基质匹配标准计算来补偿基质诱导的抑制作用。通过对添加了0.01、0.05和0.1mg/kg的空白马铃薯样品进行五次重复加标回收实验，确定了该方法的精密度和准确性。获得的回收率范围为74%-110%，所有浓度的相对标准偏差值均<5%。
