Surface modification by grafting of poly(SBMA-co-AEMA)-g-PDA coating and its application in CE.

In this paper, a novel copolymer consisting of sulfobetaine methacrylate (SBMA) and 2-aminoethyl methacrylate (AEMA) named as poly(SBMA-co-AEMA) was synthesized by conventional free-radical polymerization, the poly(SBMA-co-AEMA) zwitterionic copolymer was immobilized onto glass slides surface through polydopamine (PDA)-anchored coating and formed poly(SBMA-co-AEMA)-g-PDA coating. The defined copolymer was characterized by nuclear magnetic resonance hydrogen spectroscopy ((1)H NMR) and gel permeation chromatography. The surface morphology, thickness, and chemical component of poly(SBMA-co-AEMA)-g-PDA coating were studied by atom force microscope, ellipsometry, and X-ray photoelectron spectroscopy, respectively. The hydrophilicity and stability of these coatings were investigated by static water contact angles. And finally, the poly(SBMA-co-AEMA)-g-PDA coating was successfully applied into capillary inner surface for suppression electro-osmotic flow and protein separation by capillary electrophoresis.