固定金属亲和磁性吸附剂对有机磷农药残留的固相萃取性能

Solid Phase Extraction of Organophosphorous Pesticides Based on Immobilized Metal Ions Affinity Magnetic Adsorbent

本研究首先合成了磁性氨基化多壁碳纳米管,然后在其表面修饰亚氨基二乙酸,最后螯合Zr^(4+)、Ti^(4+)、Fe^(3+)、Cu^(2+)、Zn^(2+),制备了5种固定金属亲和磁性吸附剂。通过红外光谱、透射电镜、X射线光电子能谱对吸附剂进行了表征;采用静态吸附法,研究了螯合不同金属离子的吸附剂对乐果、乙酰甲胺磷吸附量的影响,考察了吸附和洗脱条件对乐果富集效果的影响。结果表明,螯合Ti 4+的磁性多壁碳纳米管对乐果的吸附量最大,最佳吸附时间和洗脱时间分别为60 min和30 min,最佳洗脱剂为丙酮,用量为1.5 mL。本文建立的检测有机磷农药残留样品前处理方法,操作简便,有机溶剂用量少,具有较好应用前景。

Magnetic multi-wall carbon nanotubes(mMWCNTs)was prepared,following with modification of iminodiacetic acid(IDA)and chelating of Zr^(4+),Ti^(4+),Fe^(3+),Cu^(2+) and Zn^(2+) to obtain the immobilized metal ions affinity nano-adsorbent.The adsorbent was characterized by Fourier transform infrared spectroscopy,transmission electron microscopy and X-ray photoelectron spectroscopy.The effects of immobilized ions on the adsorption amount of acephate and dimethoate were studied by static adsorption method.Meanwhile,the adsorption and elution time,the elution solvent and elution volume were optimized.The results indicate that the mMWCNTs chelated with Ti 4+exhibit the highest adsorption amount towards dimethoate.The optimal adsorption and elution time are 60 min and 30 min,respectively.The best elution solvent is acetone and elution volume is 1.5 mL.The sample preparation method for organophosphorus pesticides in this study is of great advantages,such as easy manipulation,a little organic solvent involved.Therefore,the method is of great practical applications.