固相萃取-高效液相色谱法测定4种蔬果中2,4-D的残留量

Determination of 2,4- D Acid Residues in Four Kinds of Vegetables and Fruits by Solid Phase Extraction and High Performance Liquid Chromatography

为建立蔬果中2,4-D残留量高效液相色谱(HPLC)检测方法,以固相萃取为净化手段,采用HPLC法检测番茄、葡萄、枇杷和黄瓜4种蔬果中2,4-二氯苯氧乙酸(2,4-D)的残留量。结果表明,样品经碱性水溶液提取、酸化,C18固相萃取小柱净化后,能够有效排除杂峰干扰,2,4-D残留量检测准确。该方法的线性相关系数为0.9980,检测限为0.0012 mg·kg^(-1),2,4-D的添加回收率为81.8%~116.0%,变异系数(CV)小于6%,表明方法准确度高,能满足番茄、葡萄、枇杷和黄瓜产品中2,4-D残留量的检测。采用此方法测定番茄等4种蔬果21份样品,样品中仅有2份番茄样品检测出2,4-D,残留量均小于0.02mg·kg^(-1)。本研究为利用HPLC检测果蔬中2,4-D残留量奠定了理论基础。

In order to establish the determination of 2,4-dichlorophenoxyacetic acid（2,4-D） residues by high-performance liquid chromatography（HPLC）,four vegetables and fruits of tomato, grape, loquat and cucumber were determined by solid phase extraction and high-performance liquid chromatography （SPE-HPLC） in this paper. The sample was extracted and acidified with alkali aqueous solution, and purified by the SPE-C18 column. The results indicated that the analysis method was accurate, with correlation coefficient of 0.9980, and detecting limit of 2,4-D acid were 0.0012 mg·kg^-1, and the average recoveries ranged from 81.8% to 116.0%, and the coefficient of variation （CV） was less than 6%, which can be used for determined 2,4-D acid residues in above-mentioned four kinds of vegetables and fruits. 2,4-D acid residues in 21 samples of four kinds of vegetables and fruits were determined in this method, and only 2 tomato samples were determined 2,4-D acid residues, with less than 0.02 mg·kg^-1. The above experiments provided basis for the detection of 2,4-D acid residues in 4 kinds of fruits and vegetables by HPLC.