人血清白蛋白微/纳米管的制备及影响因素

Preparation of Human Serum Albumin Micro/Nanotubes

以聚碳酸酯(polycarbonate,PC)为模板,聚乙烯亚胺(polyethyleneimine,PEI)为连接剂,采用静电层层自组装技术制备了人血清白蛋白(human serum albumin,HSA)微米管和纳米管,讨论了溶液pH、离子强度、组装层数、沉淀清洗次数和模板孔径对组装效果的影响。利用扫描电子显微镜(SEM)、透射电子显微镜(TEM)、傅里叶变换红外光谱仪(FTIR)和X射线能谱仪(EDS)对蛋白质微/纳米管的结构和组成进行了表征。结果表明,溶液pH和离子强度是影响组装效果的关键因素,在HSA和PEI溶液pH分别为7.4和10.3,且PEI溶液不含NaCl的条件下组装得到的微/纳米管具有良好的中空开口管状结构;微/纳米管的外径由模板孔径决定;调节组装层数可控制管壁厚度,且组装层数越多,管壁越厚,由此可实现对微/纳米管内径大小的调控;为保证管状结构的完整性,避免较薄的管壁在模板溶解和真空干燥过程中造成破坏,PEI/HSA双分子层数应不少于3;采用极性胺基溶剂N,N-二甲基甲酰胺(N,N-Dimethylformamide,DMF)可较好地溶解PC模板从而释放管状物。

In this research,protein micro/nanotubes were fabricated by alternate layer-by-layer（LbL）assembly of human serum albumin（HSA）and polyethyleneimine（PEI）into polycarbonate（PC）membranes.The experimental conditions of pH values,ionic strength,the depositions cycles and the diameter of porous membrane were discussed.The morphology and composition of tubes were characterized by scanning electron microscope（SEM）,transmission electron microscope（TEM）,fourier transform infrared spectroscopy（FTIR）and energy dispersive spectroscopy（EDS）.The results show that pH and ionic strength of the solution are the key factors that influence the effect of assembly.Micro/nanotubes with good opening hollow tubular structure were obtained when pH 7.4HSA solution and pH 10.3PEI solution without NaCl were used in synthesis procedure.The outer diameter of tube was dependent on the PC template,thus the micro/nanotubes size was controlled by the wall thickness,which can be adjusted by the number of layers of the HSA and PEI deposited along the pore walls.To avoid the thin wall being damaged in dissolving the template and vacuum drying,the PEI/HSA bilayer number should not be less than 3.The polar solvent N,N-dimethylformamide（DMF）can dissolve PC template to release the micro/nanotubes.