Nanoprobe Laboratory for Bio- & Nanotechnology and Biomimetics, The Ohio State University, Columbus, Ohio 43210, USA.
J Biomed Mater Res A. 2012 Apr;100(4):978-88. doi: 10.1002/jbm.a.34033. Epub 2012 Jan 25.
The conformational changes of fibronectin (FN) deposited on various block copolymers where one block is composed of poly(methyl methacrylate) (PMMA) and the other block is either poly(acrylic acid) (PAA) or poly(2-hydroxyethyl methacrylate) (PHEMA) were investigated using a functionalized atomic force microscope (AFM) tip. The tip was modified with an antibody sensitive to the exposure of the arginine-glycine-aspartic acid (RGD) groups in FN. By studying the adhesive interactions between the antibody and the proteins adsorbed on the block copolymer surface and phase imaging, it was found that the triblock copolymers PAA-b-PMMA-b-PAA and PMMA-b-PHEMA-b-PMMA, which both have large domain sizes, are conducive to the exposure of the FN RGD groups on the surface. On the basis of these results, it is concluded that the surface chemistry as well as the nanomorphology dictated by the block copolymer arrangement could both tune protein conformation and orientation and optimize cell adhesion to the biomaterial surface.
使用功能化原子力显微镜（AFM）探针研究了纤维连接蛋白（FN）在各种嵌段共聚物上的构象变化，其中一个嵌段由聚甲基丙烯酸甲酯（PMMA）组成，另一个嵌段是聚丙烯酸（PAA）或聚（2-羟乙基甲基丙烯酸酯）（PHEMA）。探针用一种对 FN 中精氨酸-甘氨酸-天冬氨酸（RGD）基团暴露敏感的抗体进行了修饰。通过研究抗体与吸附在嵌段共聚物表面的蛋白质之间的粘附相互作用和相成像，发现具有较大畴尺寸的两亲性嵌段共聚物 PAA-b-PMMA-b-PAA 和 PMMA-b-PHEMA-b-PMMA 有利于 FN RGD 基团在表面上的暴露。基于这些结果，可以得出结论，表面化学和由嵌段共聚物排列决定的纳米形态都可以调节蛋白质的构象和取向，并优化细胞对生物材料表面的粘附。
