分子印迹聚合物微球结构与性能的关系

The Relationships between Structure and Properties of Molecularly Imprinted Polymeric Microspheres

以咖啡因为模板分子,采用单步溶胀聚合法制备了一系列具有不同结构特点的分子印迹聚合物微球(MIPMs),考察了MIPMs结构与吸附及识别性能的关系。结果表明:增大MIPMs的比表面积、在一定范围内提高MIPMs的溶胀率或增大结合点的密度,均可增加MIPMs中可接近性结合点的数量,从而增强MIPMs对咖啡因的吸附与识别能力;提高MIPMs的刚性,可增强印迹孔穴的稳定性,MIPMs的识别能力增强,但吸附能力减弱。研究还从热力学角度分析了MIPMs中不同类型结合点的吸附与识别能力。结果表明,高亲和力结合点比低亲和力结合点具有更强的吸附与识别能力。

A series of molecularly imprinted polymeric microspheres （MIPMs） with different structures were prepared via a single-step swelling and polymerization method with caffeine as template molecules. The relationships between structure and adsorption and recognition capabilities of the MIPMs were then investigated. The results indicate that the adsorption and recognition capabilities of the MIPMs for the template molecules can be enhanced by enlarging their specific surface area, increasing their swelling ratio or their density of binding sites within a certain range, since those means increase the number of accessible binding sites of the MIPMs. It was also found that, increasing the stiffness of the MIPMs, the stabilities of imprinted cavities may be enhanced, thereby enhances the recognition capabilities of the MIPMs for the template molecules, but weakens the adsorption capabilities of the MIPMs at the same time. Moreover, the adsorption and recognition capabilities of different binding sites of the MIPMs were analyzed from the perspective of thermodynamics. The results show that the adsorption and recognition capabilities of the binding sites with high affinity are much better than that of the binding sites with low affinity.