Singh Nripen, Cui Xiaofeng, Boland Thomas, Husson Scott M
Department of Chemical and Biomolecular Engineering, Clemson University, Clemson, SC 29634, USA.
Biomaterials. 2007 Feb;28(5):763-71. doi: 10.1016/j.biomaterials.2006.09.036. Epub 2006 Oct 17.
This contribution demonstrates a simple and reproducible method for fabricating surface-tethered polymer brushes that vary in grafting density and layer thickness for peptide adsorption and cell-adhesion studies. Surface-initiated atom transfer radical polymerization was used together with thiol self-assembly to generate these nanothin polymer brush layers of poly((polyethylene glycol) methacrylate). A kinetic study was done to measure the layer thickness growth rate at room temperature from flat gold substrates presenting different polymerization initiator molecule surface densities. The polymer brush layers transition from mushroom to brush regimes with increasing grafting density. A crossover density of 0.038+/-0.005 chains/nm(2) was determined for the PPEGMA polymer brushes. The results described in this paper show that layer properties such as wettability and dry layer thickness depend strongly on initiator surface density. Ultimately, the adsorbed concentration of an RGD-containing synthetic peptide Gly-Arg-Gly-Asp-Ser and the adhesion and spreading of cells were correlated with surface properties, which continues to be a major research theme in biomedical and biomaterials research.
本论文展示了一种简单且可重复的方法，用于制备表面 tethered 聚合物刷，这些聚合物刷在接枝密度和层厚度方面有所不同，用于肽吸附和细胞粘附研究。表面引发的原子转移自由基聚合与硫醇自组装一起用于生成聚（甲基丙烯酸聚乙二醇酯）的这些纳米薄聚合物刷层。进行了动力学研究，以测量室温下从呈现不同聚合引发剂分子表面密度的平坦金基底上的层厚度生长速率。随着接枝密度的增加，聚合物刷层从蘑菇状转变为刷状状态。确定了 PPEGMA 聚合物刷的交叉密度为 0.038±0.005 链/nm²。本文所述结果表明，诸如润湿性和干层厚度等层性质强烈依赖于引发剂表面密度。最终，含 RGD 的合成肽 Gly-Arg-Gly-Asp-Ser 的吸附浓度以及细胞的粘附和铺展与表面性质相关，这仍然是生物医学和生物材料研究中的一个主要研究主题。
