Laboratory of Biomedical Material Engineering, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian 116023, China.
Langmuir. 2012 Sep 18;28(37):13261-73. doi: 10.1021/la302615t. Epub 2012 Sep 4.
Alginate/chitosan/alginate (ACA) hydrogel microcapsules were modified with methoxy poly(ethylene glycol) (MPEG) to improve protein repellency and biocompatibility. Increased MPEG surface graft density (n(S)) on hydrogel microcapsules was achieved by controlling the grafting parameters including the buffer layer substrate, membrane thickness, and grafting method. X-ray photoelectron spectroscopy (XPS) model was employed to quantitatively analyze n(S) on this three-dimensional (3D) hydrogel network structure. Our results indicated that neutralizing with alginate, increasing membrane thickness, and in situ covalent grafting could increase n(S) effectively. ACAC(PEG) was more promising than ACC(PEG) in protein repellency because alginate supplied more -COO(-) negative binding sites and prevented MPEG from diffusing. The n(S) increased with membrane thickness, showing better protein repellency. Moreover, the in situ covalent grafting provided an effective way to enhance n(S), and 1.00 ± 0.03 chains/nm(2) was achieved, exhibiting almost complete immunity to protein adsorption. This antifouling hydrogel biomaterial is expected to be useful in transplantation in vivo.
藻酸盐/壳聚糖/藻酸盐（ACA）水凝胶微胶囊用甲氧基聚乙二醇（MPEG）进行了修饰，以提高蛋白质排斥性和生物相容性。通过控制接枝参数，包括缓冲层基底、膜厚度和接枝方法，提高了水凝胶微胶囊上的 MPEG 表面接枝密度（n(S)）。X 射线光电子能谱（XPS）模型被用来定量分析这个三维（3D）水凝胶网络结构上的 n(S)。我们的结果表明，用藻酸盐中和、增加膜厚度和原位共价接枝可以有效地增加 n(S)。ACAC(PEG)在蛋白质排斥性方面比 ACC(PEG)更有前途，因为藻酸盐提供了更多的-COO(-)负结合位点，并阻止了 MPEG 的扩散。n(S)随膜厚度的增加而增加，表现出更好的蛋白质排斥性。此外，原位共价接枝提供了一种增强 n(S)的有效方法，达到了 1.00±0.03 链/nm(2)，表现出几乎完全抵抗蛋白质吸附的能力。这种抗污染水凝胶生物材料有望在体内移植中得到应用。
