中空硅球表面分子印迹温敏聚合物吸附溶液中的四环素

Hollow silica sphere surface molecularly imprinted temperature-sensitive polymers for adsorption of Tetracycline in solution

本文开展了中空温敏分子印迹聚合物(HTMIPs)吸附溶液中四环素(TC)的实验研究,采用牺牲酵母模板法制备的中空硅球作为基质材料,以TC为模板分子,N-异丙基丙烯酰胺为温敏单体,通过沉淀聚合法合成了中空温敏型TC分子的印迹聚合物,利用FT-IR和SEM等方法对HTMIPs的理化性能进行表征,通过静态吸附实验考察HTMIPs对TC的吸附性能.结果表明,HTMIPs对模板分子TC在pH值为5.0时,35℃条件下吸附容量最大,约为72.05μmol·g^(-1),表明该印迹吸附剂对TC具有良好的亲和性和选择吸附性.HTMIPs的等温吸附结果与Freundlich模型拟合更好,动力学吸附结果更符合准二级动力学吸附模型,表明HTMIPs对于TC分子的吸附主要是在非均匀表面共价键作用下的结果.同时,HTMIPs表现出良好的可重复利用性,5次重复吸附-解吸附后吸附量损失约6.64%.因此,所制备的中空温敏印迹聚合物在吸附分离环境水体中的抗生素方面有良好的实际应用前景.

In this paper,studies on the adsorption of tetracycline（ TC） from aqueous solutions by hollow temperature-sensitive molecularly-imprinted polymers（ HTMIPs） were carried out. HTMIPs were synthesized by precipitation polymerization,with hollow silica spheres as the matrix material prepared by sacrificial yeast-template method,TC as the template molecule,and N-isopropyl acrylamide as the temperature-sensitive monomer. FT-IR and SEM were applied to characterize the physical and chemical properties of the polymers. Static adsorption experiments were carried out to investigate the TC adsorption performance of HTMIPs. The results indicated that at pH 5. 0 and 35 ℃,HTMIPs achieved the maximum adsorption amount of TC（ about 72. 05 μmol·g^（-1））,and displayed high affinity and selectivity for TC. The isotherm better fitted the Freundlich model,whilekinetics results were well described by the pseudo-second-order model,which suggested that the adsorption of TC was mainly controlled by covalent bonding interactions on the nonuniform surface.HTMIPs exhibited good regeneration capacity with only 6. 64% of loss adsorption capacity after 5 adsorption-desorption cycles. HTMIPs synthesized in this study have potential practical application to adsorption and separation of antibiotics from environmental water.