title: Branched polyethyleneimine-bonded tentacle-type polymer stationary phase for peptides and proteins separations by open-tubular capillary electrochromatography.
abstract: A novel tentacle-type polymer stationary phase covalently modified with branched polyethyleneimine (PEI) was developed for peptides and proteins separations by open-tubular CEC (OT-CEC). The preparation procedure included the silanization of capillary inner wall, in situ graft polymerization and PEI functionalization. A wrinkly polymer surface of multitudinous steric amine groups was evenly formed on the capillary inner wall, and anodic EOF could be gained within a wide pH range of 2.5-7.5. The electroosmotic mobility was examined for its dependence on pH as well as PEI concentrations. Good repeatability was gained with RSD for the migration time of EOF marker within 4.8% and satisfactory chemical stability was validated. Due to the existence of amine groups on the surface of tentacle-type polymer stationary phase, the silanol effect that occurs between the positively charged biomolecules and the silanols of the capillary column was greatly suppressed. Compared with a monolayer-coating capillary, seven enkephalin-related peptides were well resolved on the PEI-bonded column with high efficiencies. Favorable separations of peptides and proteins with high column efficiencies were obtained in 144,000-189,000 and 97,000-170,000 plates/m. Branched PEI-bonded tentacle-type polymer stationary phase has been proven to afford satisfactory retention and resolution of peptides and proteins.
authors: Institute of Food Safety and Environmental Monitoring, Fuzhou University, Fuzhou, P. R. China.
authors: Xiaowei
authors: X
authors: Zhang
authors: Juan
authors: J
authors: Yang
authors: Shaofeng
authors: S
authors: Liu
authors: Xucong
authors: X
authors: Lin
authors: Zenghong
authors: Z
authors: Xie
mesh_terms: D000327:Adsorption; D053801:Capillary Electrochromatography / Q000295:instrumentation / Q000379:methods*; D010455:Peptides / Q000032:analysis / Q000302:isolation & purification*; D011094:Polyethyleneimine / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D011506:Proteins / Q000032:analysis / Q000302:isolation & purification*
chemical_list: D010455:Peptides; D011108:Polymers; D011506:Proteins; D011094:Polyethyleneimine