Grafting epoxy-modified hydrophilic polymers onto poly(dimethylsiloxane) microfluidic chip to resist nonspecific protein adsorption.
In order to achieve a simple covalent hydrophilic polymer coating on poly(dimethylsiloxane) (PDMS) microfluidic chip, epoxy modified hydrophilic polymers were synthesized in aqueous solution with a persulfate radical initiation system, and crosslinked onto PDMS pretreated by oxygen plasma and silanized with 3-aminopropyl-triethoxysilanes (APTES). Glycidyl methacrylate (GMA) was copolymerized with acrylamide (poly(AAM-co-GMA)) or dimethylacrylamide (poly(DAM-co-GMA)), and graft polymerized with polyvinylpyrrolidone (PVP-g-GMA) or polyvinylalcohol (PVA-g-GMA). The epoxy groups in the polymers were determined by UV spectra after derivation with benzylamine. Reflection absorption infrared spectroscopy (RAIRS) confirmed covalent grafting of GMA-modified polymers onto PDMS surface. Electroosmotic flow (EOF) in the polymer grafted microchannel was strongly suppressed within the range pH 3-11. Surface adsorption of lysozyme and bovine serum albumin (BSA) was reduced to less than 10% relative to that on the native PDMS surface. On the GMA-modified polymer coated PDMS microchip, basic proteins, peptides, and sodium dodecyl sulfate (SDS) denatured proteins were separated successfully.
Wu
Dapeng
D
457 Zhongshan Road, Dalian Institute of Chemical Physics, Dalian 116023, China.
Zhao
Baoxia
B
Dai
Zhongpeng
Z
Qin
Jianhua
J
Lin
Bingcheng
B
D000178:Acrylamides / Q000737:chemistry; D000327:Adsorption; D004129:Dimethylpolysiloxanes / Q000737:chemistry*; D004586:Electrophoresis / Q000379:methods; D004852:Epoxy Compounds / Q000737:chemistry; D057927:Hydrophobic and Hydrophilic Interactions; D008689:Methacrylates / Q000737:chemistry; D046210:Microfluidic Analytical Techniques / Q000379:methods*; D009113:Muramidase / Q000737:chemistry; D011142:Polyvinyl Alcohol / Q000737:chemistry; D011205:Povidone / Q000737:chemistry; D011489:Protein Denaturation; D011506:Proteins / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000737:chemistry; D012828:Silicones / Q000737:chemistry*; D013499:Surface Properties
D000178:Acrylamides; D004129:Dimethylpolysiloxanes; D004852:Epoxy Compounds; D008689:Methacrylates; D011506:Proteins; D012828:Silicones; C429790:poly(N,N-dimethylacrylamide); D012710:Serum Albumin, Bovine; C013830:baysilon; D011142:Polyvinyl Alcohol; D009113:Muramidase; D011205:Povidone; C007870:glycidyl methacrylate