A method for treating capillary walls exposable to protein solutes is provided that reduces interactions of the protein solutes with the wall and that permits control of electroosmotic flow within the capillaries by selection of solution pH. Thus, a capillary tube has an interfacial layer covalently bonded to the inner wall of the tube. This interfacial layer is effective to reduce interactions between the inner wall and protein solutes and preferably includes a hydratable amphoteric phase. The amphoteric phase is a reaction product of a protein, peptide or an ampholyte and an oxygen or nitrogen nucleophile. Electroosmotic flow magnitude and/or flow direction may be controlled when capillaries of the invention are used for electrophoretic separations.
提供了一种处理可接触蛋白质溶质的毛细管壁的方法,这种方法可减少蛋白质溶质与管壁的相互作用,并可通过选择溶液的 pH 值来控制毛细管内的电渗流。因此,毛细管的内壁上有一层共价键结合的界面层。该界面层可有效减少内壁与蛋白质溶质之间的相互作用,最好包括可
水合的两性相。两性相是蛋白质、肽或两性溶解物与氧或氮亲核物的反应产物。当本发明的毛细管用于电泳分离时,可控制电渗流的大小和/或流动方向。