通过可控沉积和交联制备蛋白质微胶囊

通过加入反溶剂控制牛血清白蛋白(BSA)在碳酸锰微粒表面的沉积, 形成连续薄膜后交联, 去除模板后得到了尺寸均匀和分散良好的BSA中空微胶囊. 囊壁厚度可以通过滴加乙醇控制; 囊壁的截留分子量在70000—155000之间. 由于BSA含有丰富的自由羧基, 得到的微胶囊表现出pH响应性. 这种快速简便制备微胶囊的方法也可以应用于其它蛋白质及酶, 得到的生物相容的微胶囊将在药物控制释放等领域具有潜在的应用价值.

Fabrication of Protein Microcapsules by Controlled Precipitation and Cross-linking

Bovine serum albumin(BSA) microcapsules, which have a uniform shape and size and can be well dispersed in water, were fabricated by the controlled precipitation of BSA on the surface of MnCO3 microparticles though desolvation, followed by cross-linking and core removal. The thickness of the capsule walls were controlled by the amount of the added non-solvent(ethanol). The as-prepared microcapsules are permeable to TRITC-dextran with a molecular weight of 70000, but not up to 155000, implying that the pore size in the capsule walls is between 18.5—26.2 nm. Due to the excessive carboxylic groups on the BSA molecules, which can be fully charged at an alkaline condition, the BSA capsules expanded their size at pH>10. This method is applicable to other proteins and enzymes as well, and the pH-sensitive protein capsules may find potential applications in biomedical field because of their biodegradability and biocompatibility.