二氯喹啉酸分子印迹聚合物微球的制备

Preparation of Molecularly Imprinted Polymers Microspheres for Quinclorac

采用改进的分散聚合方法制得的纳米级聚苯乙烯微球(PS)为种球,以二氯喹啉酸(quinclorac)为模板分子,通过单步溶胀聚合法在水相中制备了单分散分子印迹聚合物微球(MIPs)。通过红外光谱分析MIPs的结合位点;利用紫外光谱研究了MIPs的结合机理和识别特性;用扫描电镜观察了微球的形貌。结果表明,PS微球的粒径分布100～150nm,MIPs的粒径分布为200～300nm;Scatchard分析表明,MIPs在识别二氯喹啉酸过程中存在两类结合位点:高亲和性位点的解离常数KD1=0.0488mmol/L;低亲和性位点的解离常数KD2=0.423mmol/L。

Molecularly imprinted polymers（MIPs） were prepared by a one-step swelling polymerization method in aqueous system using nano-polystyrene microspheres which was gained by dispersion polymerization as seeds and using quinclorac as template molecules.The infrared spectrometry（IR） of the polymers indicated that there were some functional groups in the molecularly imprinted polymers which could interact with the template.The binding mechanism and identification characteristics of MIPs were evaluated by ultraviolet spectrometry.Morphological characterizations of the MIPs were tested by scanning electron microscope（SEM）,showing that the diameters of PS microspheres were between 100~150 nm and the diameters of MIPs were between 100~300 nm.Scatchard analysis suggested the MIPs had two classes of binding sites in recognizing quinclorac.The calculated dissociation constant KD1 of binding sites with high affinity was 0.0488 mmol/L,while KD2 of binding sites with low affinity was 0.423 mmol/L.