不同孔径MCFs的制备及其对溶菌酶的吸附性能

Abstract

以三嵌段共聚物聚氧乙烯–聚氧丙烯–聚氧乙烯(Pluronic P123)及三甲苯(TMB)为模板剂及扩孔剂，采用微乳液模板法，通过控制TMB与P123的质量比合成了一系列不同孔径的介孔泡沫分子筛(MCFs)，利用TEM、N2吸附等手段对材料进行结构及性能表征。当TMB/P123质量比由0.5增至1.0时，材料的孔径增大，当其继续增至1.5时，孔径变小；溶菌酶吸附性能测试发现，质量比为1.5时合成的MCFs，其吸附速率最快，约1 h达到平衡，且其对酶的固定最牢固，酶不易脱落，吸附量可达到490 mg/g；此外，FT-IR分析发现MCFs吸附对溶菌酶的结构无明显影响。研究结果表明，MCFs合成时的TMB/P123质量比通过影响MCFs孔结构从而对酶吸附性能产生重要的影响；MCFs有望成为优良的酶载体材料。 The mesostructured cellular foams (MCFs) were synthesized using microemulsion templating, in which the nonionic triblock copolymer surfactant Pluronic P123 was served as template and 1,3,5-trimethylbenzene (TMB) as organic swelling agent. By controlling the mass ratio of TMB/P123, a series of MCFs with different pore size were prepared, and then the structural and chemical properties of MCFs were characterized by TEM and nitrogen adsorption. It was found that the pore size of MCFs increased when the mass ratio of TMB/P123 increased from 0.5 to 1.0, while that of MCFs decreased when the mass ratio continuously increased to 1.5. The MCFs were used as adsorbent for the adsorption of lysozyme. The maximum adsorption rate was obtained on MCFs-1.5 (mass ratio of TMB/P123 was 1.5), meaning that the sample reached equilibrium within 1 h. The immobilization of lysozyme on MCFs-1.5 prevented the leaching of enzyme effectively and the immobilized amount was up to 490 mg/g. Furthermore, FT-IR analysis revealed that the lysozyme adsorbed on MCFs could be held without evident structure changes. This study suggested that enzyme loading efficiency was clearly dependent on the size matching between the enzyme molecules and carrier pores, and the synthesized MCFs could be applied as excellent carriers for enzyme immobilization.