École Polytechnique Fédérale de Lausanne (EPFL), Institut des Matériaux and Institut des Sciences et Ingénierie Chimiques, Laboratoire des Polymères, Bâtiment MXD, Station 12, CH-1015 Lausanne, Switzerland.
Biomacromolecules. 2010 Dec 13;11(12):3467-79. doi: 10.1021/bm101297w. Epub 2010 Nov 19.
Polymer brushes represent an interesting platform for the development of high-capacity protein binding surfaces. Whereas the protein binding properties of polymer brushes have been investigated before, this manuscript evaluates the feasibility of poly(glycidyl methacrylate) (PGMA) and PGMA-co-poly(2-(diethylamino)ethyl methacrylate) (PGMA-co-PDEAEMA) (co)polymer brushes grown via surface-initiated atom transfer radical polymerization (SI-ATRP) as protein reactive substrates in a commercially available microarray system using tantalum-pentoxide-coated optical waveguide-based chips. The performance of the polymer-brush-based protein microarray chips is assessed using commercially available dodecylphosphate (DDP)-modified chips as the benchmark. In contrast to the 2D planar, DDP-coated chips, the polymer-brush-covered chips represent a 3D sampling volume. This was reflected in the results of protein immobilization studies, which indicated that the polymer-brush-based coatings had a higher protein binding capacity as compared to the reference substrates. The protein binding capacity of the polymer-brush-based coatings was found to increase with increasing brush thickness and could also be enhanced by copolymerization of 2-(diethylamino)ethyl methacrylate (DEAEMA), which catalyzes epoxide ring-opening of the glycidyl methacrylate (GMA) units. The performance of the polymer-brush-based microarray chips was evaluated in two proof-of-concept microarray experiments, which involved the detection of biotin-streptavidin binding as well as a model TNFα reverse assay. These experiments revealed that the use of polymer-brush-modified microarray chips resulted not only in the highest absolute fluorescence readouts, reflecting the 3D nature and enhanced sampling volume provided by the brush coating, but also in significantly enhanced signal-to-noise ratios. These characteristics make the proposed polymer brushes an attractive alternative to commercially available, 2D microarray surface coatings.
聚合物刷代表了开发高容量蛋白质结合表面的一个有趣平台。虽然聚合物刷的蛋白质结合性质已经得到了研究，但本文评估了通过表面引发原子转移自由基聚合（SI-ATRP）生长的聚（甲基丙烯酸缩水甘油酯）（PGMA）和 PGMA-co-聚（2-（二乙氨基）乙基甲基丙烯酸酯）（PGMA-co-PDEAEMA）（共）聚合物刷作为商业上可用的基于氧化钽的光波导芯片微阵列系统中的蛋白质反应性底物的可行性。使用商业上可用的十二烷基磷酸酯（DDP）改性芯片作为基准，评估基于聚合物刷的蛋白质微阵列芯片的性能。与 2D 平面的 DDP 涂层芯片相比，聚合物刷覆盖的芯片代表了 3D 采样体积。这反映在蛋白质固定化研究的结果中，表明与参考基底相比，聚合物刷基涂层具有更高的蛋白质结合能力。发现聚合物刷基涂层的蛋白质结合能力随着刷厚度的增加而增加，并且通过共聚 2-（二乙基氨基）乙基甲基丙烯酸酯（DEAEMA）也可以增强，该共聚体能催化缩水甘油甲基丙烯酸酯（GMA）单元的环氧化物开环。通过两个概念验证微阵列实验评估了基于聚合物刷的微阵列芯片的性能，该实验涉及生物素-链霉亲和素结合的检测以及 TNFα 反向测定的模型。这些实验表明，使用聚合物刷修饰的微阵列芯片不仅导致了最高的绝对荧光读数，反映了刷涂层提供的 3D 性质和增强的采样体积，而且还导致了显著增强的信号噪声比。这些特性使得所提出的聚合物刷成为商业上可用的 2D 微阵列表面涂层的有吸引力的替代品。
