Fabrication of bovine serum albumin microcapsules by desolvation and destroyable cross-linking

Bovine serum albumin (BSA) mono-component microcapsules were fabricated by a method of desolvation and destroyable cross-linking. Desolvation of BSA from its aqueous solution was achieved by dropwise addition of ethanol. The dissolvable content of BSA in the supernatant decreased along with the increase of ethanol volume. Adsorption of the desolvated BSA onto MnCO3 microparticle surfaces and further cross-linking with disulfide- containing dithiobis(succinimidylpropionate) smoothed the rough surfaces of the MnCO3 microparticles. Hollow and intact microcapsules were obtained after core removal at low pH. Wall thickness of the microcapsules could be controlled by the amount of ethanol. Measured by confocal laser scanning microscopy, about 70% of these microcapsules were shown to be impermeable to fluorescein isothiocyanate-labeled dextran with a molecular weight of 2000 kDa. Destruction of the BSA microcapsules was achieved under the treatment with a reductive agent (NaBH4) and ultrasonication. With the ease of fabrication and the features of biocompatibility, degradability and environmentally controlled destroyability, these microcapsules could be attractive in applications in the fields of pharmacology, medicine and cosmetics etc.