National Referral Laboratory, ICAR-National Research Centre for Grapes, P.O. Manjri Farm, Pune 412307, India.
J Agric Food Chem. 2015 May 13;63(18):4449-56. doi: 10.1021/jf505221e. Epub 2015 Feb 10.
A buffered ethyl acetate extraction method is proposed for the simultaneous analysis of 296 agrochemicals in a wide range of fruit and vegetable matrices by liquid chromatography-tandem mass spectrometry (LC-MS/MS). The optimized quantity of acetate buffer (1% acetic acid + 0.5 g of sodium acetate per 10 g of sample) adjusted the pH of each test matrix to 5-6, which in turn significantly improved recoveries of acidic and basic compounds. The role of diethylene glycol (used in the evaporation step) on signal suppression of certain compounds was evaluated, and its quantity was optimized to minimize such an effect. The method was validated in grape, mango, drumstick, bitter gourd, capsicum, curry leaf, and okra as per the DG-SANCO/12571/2013 guidelines. Recoveries in the fortification range of 1-40 μg/kg were within 70-120% with associated relative standard deviations below 20% for most of the compounds. The method has potential for regulatory and commercial applications with a generic approach.
提出了一种缓冲乙酸乙酯提取方法，用于通过液相色谱-串联质谱（LC-MS/MS）同时分析多种水果和蔬菜基质中 296 种农药。优化的乙酸盐缓冲液（每 10 克样品中含 1%乙酸和 0.5 克醋酸钠）的用量将每种测试基质的 pH 值调节至 5-6，这反过来显著提高了酸性和碱性化合物的回收率。评估了二乙二醇（在蒸发步骤中使用）对某些化合物信号抑制的作用，并优化了其用量以最小化这种影响。根据 DG-SANCO/12571/2013 指南，该方法在葡萄、芒果、鼓槌、苦瓜、辣椒、咖喱叶和秋葵中进行了验证。在 1-40μg/kg 的添加范围内，大多数化合物的回收率在 70-120%之间，相关相对标准偏差低于 20%。该方法具有通用方法的监管和商业应用潜力。
