【摘要】 本文发展了一种对蛋白质具有吸附/释放功能的二元混合刷涂层（BBC）毛细管,并将其用于蛋白质的在线富集.通过阳离子开环聚合可逆加成断裂链转移聚合,分别合成了末端为氨基的聚（2-甲基-2噁唑琳）（PMOXA-NH2）以及末端为巯基的聚丙烯酸（PAA-SH）.然后通过聚多巴胺黏合层将PMOXA-NH2和PAASH依次接枝到熔融硅毛细管内表面,制备出基于聚（2-甲基-2-噁唑琳）（PMOXA）和聚丙烯酸（PAA）的BBC毛细管.利用扫描电镜、X射线光电子能谱分析了在毛细管内表面或毛细管原材料上形成的PMOXA/PAA涂层的厚度及组成.通过荧光显微镜研究了一定pH及离子强度（Ⅰ）下,BBC毛细管对蛋白质的吸附/释放功能.结果表明,pH=5.0 (I=10^-5 mol/L)时,BBC毛细管可以吸附牛血清蛋白（BSA）,而当pH=9.0 (I=10^-1 mol/L)时,吸附的BSA可被释放出来.将这种具有蛋白质吸附/释放功能的涂层管用于毛细管电泳在线富集BSA,以提高BSA的检测灵敏度.结果表明,在最佳条件下,BSA的灵敏度增强因子超过了5000.更多还原

【Abstract】 In this work, a binary-mixed-brushes-coated（BBC） capillary with switchable protein adsorption/desorption properties was developed and applied for on-line preconcentration of proteins. Firstly, amine-terminated poly（2-methyl-2-oxazoline）（PMOXA-NH2） and thiolterminated poly（acrylic acid）（PAA-SH） were synthesized by using cationic ring-opening polymerization（CROP） and reversible addition fragmentation chain transfer（RAFT） polymerization, respectively. Then, the BBC capillary based on poly（2-methyl-2-oxazoline）（PMOXA） and poly（acrylic acid）（PAA） was prepared by sequentially grafting of PMOXANH2 and PAA-SH onto fused-silica capillary inner surface through poly（dopamine）（PDA）as an anchor. The obtained PMOXA/PAA coating formed on the capillary or capillary’s raw material was characterized in terms of the thickness, surface chemical composition by using scanning electron microscope（SEM） and X-ray photoelectron spectrum（XPS）. The switchable protein adsorption/desorption performance of the BBC capillary was investigated by using fluorescence microscope under different solutions with certain pH and ionic strength（I）. The results showed that bovine serum albumin（BSA） could be adsorbed on BBC capillary at pH=5.0(I=10^-5 mol/L), and then the adsorbed BSA could be released at pH=9.0（I=0.1 mol/L）. This switchable protein adsorption/desorption property of coated capillary was then used to preconcentrate proteins on-line for increasing the detection sensitivity of BSA in capillary electrophoresis（CE）. With this method, a sensitivity enhancement factor（SEF） more than 5000 for BSA detection was obtained.更多还原