Transferrin gated mesoporous silica nanoparticles for redox-responsive and targeted drug delivery

This work reports on a targeted and controlled drug delivery system based on protein decorated mesoporous silica nanoparticles (MSNs). In this system, transferrin (Tf), a naturally existing protein, is grafted on the surfaces of MSNs via redox-cleavable disulfide bonds, serving as both a capping agent and a targeting ligand simultaneously. The uniform particles with ordered mesoporous structures and the successful construction of the Tf/MSN hybrid nanocarriers can be confirmed through combined techniques. It is found that the model anticancer drug doxorubicin (DOX) can be efficiently encapsulated in the MSNs in the absence of glutathione (GSH), and a burst release of DOX is observed when the system is exposed to GSH, indicating good capping efficiency of Tf and redox-responsive release of DOX. Owing to the biocompatible Tf shell, the hybrid nanocarriers exhibited excellent biocompatibility in a wide concentration range and enhanced intracellular accumulation and targeting capability to tumor cells in vitro. The facile approach and the strategy of integration of multifunctions into one moiety present great potential in site-specific, controlled-release drug delivery system and provide us new ideas in design of MSN-based nanocontainers.