含不同基团的聚丙烯酰胺改性毛细管柱的制备及应用

在丙烯酰胺、N,N-亚甲基双丙烯酰胺的混合溶液添加烯丙基胺或乙烯基磺酸钠,得到混合单体溶液,引入毛细管中,经热自由基引发原位聚合并键合到管壁上,制得化学改性的毛细管柱。通过调节烯丙基胺、乙烯基磺酸钠的加入量,得到荷电不同的聚合物。共制备了5根改性柱,发现带有氨基的聚合物涂层优于磺酸基及中性聚合物涂层。进一步比较3根氨基柱的分离效果,单体混合液中含有0.15 mol/L丙烯酰胺、0.03 mol/LN,N-亚甲基双丙烯酰胺及>1 mol/L的烯丙基胺时,制得的改性柱效果最好,可以方便地调节电渗流,并能有效抑制蛋白质的吸附,用其对鸡卵清蛋白进行区带电泳,显示出良好的分离度及重现性。

Preparation and Application of Capillary Columns Modified by Polyacrylamide with Different Groups

Allyamine or sodium vinyl sulfate was added into the solutions of acrylamide and N,N′-methylenebisacrylamide to make mixed monomer solutions. These solutions were respectively introduced in methacrylsiloxane-modifidied capillaries. In situ polymerization was initiated by thermally induced radicals. A polymer layer was chemically bonded to the inner wall, resulting in valently modified capillary columns. By altering the addition amounts of allyamine or sodium vinyl sulfate, differently charged polymeric layers were obtained. Five columns were prepared. The result indicated that columns modified with polymers containing amino groups were advantageous over those containing sulphonic acid groups or none. Further comparison revealed that the columns modified with a solution containing 0.15 mol/L acrylamide, 0.03 mol/L N,N′-methylenebisacrylamide and more than 1 mol/L allylamine exhibited good resolution. It is convenient to adjust electroosmotic flows(EOFs) in the columns by this way. In the meantime unspecific protein adsorption was efficiently depressed. When subjected) to zone electrophoresis of proteins from chicken egg white, the column showed high resolution and good reproducibility.