Facile synthesis and performance studies of BSA and PDA@Ag hollow microcapsules using SiO2 microspheres as the templates

This paper describes a general strategy that uses dopamine as a stable anchor to present protein molecules on the surface of silicon microspheres via self-assembled method (SAM), and after the removal of templates, the bovine serum albumin (BSA) microcapsules were successfully prepared. Two self assembling methods are described here, one is using glutaraldehyde (GA) as crosslinking agent to modify multilayer protein on the surface of silicon microspheres; In another way, dopamine is used as a anchor layer to graft the BSA monolayers onto silicon templates. The BSA coated silicon microspheres and BSA hollow microcapsules were characterized by transmission electron microscopy (TEM) and field emission scanning electron microscopy (FESEM). The biocompatibility of the BSA coated silicon microspheres was evaluated in vitro by MTT method. Then the polydopamine (PDA) hollow microcapsules was prepared using SiO2 nanoparticles as the templates, and Ag namoparticles was then modified on the PDA capsules. The catalytic performance of SiO2@ PDA@Ag microspheres for methylene blue (MB) was studied. And the Escherichia coli and Staphylococcus aureus was used as the indicator bacteria to investigate the antimicrobial activity of the obtained SiO2@ PDA@Ag microspheres.