Wu Dapeng, Zhao Baoxia, Dai Zhongpeng, Qin Jianhua, Lin Bingcheng
457 Zhongshan Road, Dalian Institute of Chemical Physics, Dalian 116023, China.
Lab Chip. 2006 Jul;6(7):942-7. doi: 10.1039/b600765a. Epub 2006 May 5.
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.
为了在聚二甲基硅氧烷（PDMS）微流控芯片上实现简单的共价亲水性聚合物涂层，采用过硫酸根引发体系在水溶液中合成了环氧改性亲水性聚合物，并将其交联到经氧等离子体预处理并用3-氨丙基三乙氧基硅烷（APTES）硅烷化的PDMS上。甲基丙烯酸缩水甘油酯（GMA）与丙烯酰胺（聚（AAM-co-GMA））或二甲基丙烯酰胺（聚（DAM-co-GMA））共聚，并与聚乙烯吡咯烷酮（PVP-g-GMA）或聚乙烯醇（PVA-g-GMA）接枝聚合。聚合物中的环氧基团在与苄胺衍生化后通过紫外光谱测定。反射吸收红外光谱（RAIRS）证实了GMA改性聚合物在PDMS表面的共价接枝。在pH 3-11范围内，聚合物接枝微通道中的电渗流（EOF）受到强烈抑制。相对于天然PDMS表面，溶菌酶和牛血清白蛋白（BSA）的表面吸附降低至小于10%。在GMA改性聚合物涂层的PDMS微芯片上，成功分离了碱性蛋白质、肽和十二烷基硫酸钠（SDS）变性蛋白。
