Key Laboratory of Functional Polymer Materials of MOE, Institute of Polymer Chemistry, Nankai University, Tianjin, 300071, PR China.
Colloids Surf B Biointerfaces. 2013 Aug 1;108:205-11. doi: 10.1016/j.colsurfb.2013.03.007. Epub 2013 Mar 16.
Biodegradable shell cross-linked nanocapsules were prepared via layer-by-layer assembly of PADH (tertiary amine and hydrazide grafted polyaspartamide) and PACA (carboxyl and aldehyde grafted polyaspartamide) on silica spheres. Both of the polyaspartamide derivatives are water-soluble and biodegradable polymers with a protein-like structure, and obtained by aminolysis reaction of polysuccinimide. The latter is prepared by thermal polycondensation of aspartic acid. Dynamic light scattering and zeta potential measurements were used to analyze the layer-by-layer assembly process. Bovine serum albumin (BSA), as a model protein, was entrapped in the nanocapsules via electrostatic adsorption. Nanocapsules encapsulating BSA were prepared via layer-by-layer assembly on protein-entrapping amino-functionalized silica spheres, hydrazone cross-linking and silica core removal. The BSA release profiles exhibited a pH-dependent behavior. BSA release rate increased significantly as the ambient pH dropped from the physiological pH to acidic. Cell viability study suggests that the obtained polymeric nanocapsules have good biocompatibility. These kinds of novel composite nanocapsules may offer a promising delivery system for proteins.
通过在二氧化硅球上层层组装 PADH（叔胺和酰肼接枝聚天冬氨酸）和 PACA（接枝羧基和醛基的聚天冬氨酸）制备可生物降解的壳交联纳米胶囊。两种聚天冬氨酸衍生物都是水溶性和可生物降解的聚合物，具有蛋白质样结构，通过聚琥珀酰亚胺的氨解反应获得。后者通过天冬氨酸的热缩聚制备。动态光散射和 zeta 电位测量用于分析层层组装过程。牛血清白蛋白（BSA）作为模型蛋白，通过静电吸附包埋在纳米胶囊中。通过在包埋蛋白质的氨基功能化二氧化硅球上进行层层组装、腙键交联和二氧化硅核去除，制备包埋 BSA 的纳米胶囊。BSA 的释放曲线表现出 pH 依赖性。随着环境 pH 值从生理 pH 值降至酸性，BSA 的释放速率显著增加。细胞活力研究表明，所得到的聚合物纳米胶囊具有良好的生物相容性。这些新型复合纳米胶囊可为蛋白质提供有前途的递药系统。
