Preparation and characterization of brush-like PEGMA-graft-PDA coating and its application for protein separation by CE

In this paper, a novel brush-like copolymer consisting of poly(ethylene glycol) methyl ether methacrylate and 2-aminoethyl methacrylate (AEMA) named as poly(PEGMA₃₀₀-co-AEMA) was synthesized by atom transfer radical polymerization (ATRP), and then, poly(PEGMA₃₀₀-co-AEMA) copolymer was immobilized onto material surfaces through polydopamine (PDA)-anchored coating. The defined copolymer structure was characterized by nuclear magnetic resonance hydrogen spectroscopy (¹H NMR) and gel permeation chromatography (GPC). The chemical component and surface morphology of the brush-like copolymer-graft-PDA coating were studied by using X-ray photoelectron spectroscopy (XPS) and scanning electron microscope (SEM), respectively. The hydrophilicity of the brush-like copolymer-graft-PDA coating was investigated by using static water contact angle. The protein-resistant property of the brush-like copolymer-graft-PDA coating was investigated by using quartz crystal microbalance with dissipation (QCM-D), and finally the coating was applied to capillary inner surface for protein separation by capillary electrophoresis (CE).