Enhancement of Surface Graft Density of MPEG on Alginate/Chitosan Hydrogel Microcapsules for Protein Repellency
Enhancement of Surface Graft Density of MPEG on Alginate/Chitosan Hydrogel Microcapsules for Protein Repellency
复制标题
提高海藻酸盐/壳聚糖水凝胶微胶囊上 MPEG 的表面接枝密度以实现蛋白质排斥性
DOI：
10.1021/la302615t
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发表时间：
2012-09-18
期刊：
影响因子：
3.9
通讯作者：
Ma, Xiaojun
中科院分区：
文献类型：
--
作者：
Zheng, Jiani;Xie, Hongguo;Ma, Xiaojun
采用甲氧基聚乙二醇（MPEG）对海藻酸盐/壳聚糖/海藻酸盐（ACA）水凝胶微胶囊进行改性，以提高其蛋白质驱避性和生物相容性。通过控制缓冲层基质、膜厚度和接枝方式等接枝参数，可以提高水凝胶微胶囊上MPEG表面接枝密度（n(S)）。采用x射线光电子能谱（XPS）模型定量分析该三维（3D）水凝胶网络结构中的n(S)。结果表明，用海藻酸盐中和、增加膜厚度和原位共价接枝可以有效地提高n(S)。由于海藻酸盐提供了更多的- coo -负结合位点，阻止了MPEG的扩散，ACAC（PEG）在蛋白质驱避方面比ACC（PEG）更有前景。n(S)随膜厚的增加而增加，表现出较好的蛋白驱避性。此外，原位共价接枝提供了有效的增强n(S)的途径，达到1.00 +/- 0.03链/nm(2)，对蛋白质吸附几乎完全免疫。这种防污水凝胶生物材料有望用于体内移植。
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.