Guiding mesenchymal stem cell differentiation using mesoporous silica nanoparticle-based films.

The development of smart interfaces that can guide tissue formation is of great importance in the field of regenerative medicine. Nanoparticles represent an interesting class of materials that can be used to enhance regenerative treatments by enabling close control over surface properties and directing cellular responses. Moreover, nanoparticles can be used to provide temporally controlled delivery of (multiple) biochemical compounds. Here, we exploited the cargo loading and surface functionalization properties of mesoporous silica nanoparticles (MSNs) to design films that can guide human mesenchymal stem cell (hMSC) differentiation towards the osteogenic lineage. We developed biocompatible MSN-based films that support stem cell adhesion and proliferation and demonstrated that these MSN films simultaneously allowed efficient local delivery of biomolecules without effecting film integrity. Films loaded with the osteogenesis-stimulating drug dexamethasone (Dex) were able to induce osteogenic differentiation of hMSCs in vitro. Dex delivery from the films led to increased alkaline phosphatase levels and matrix mineralization compared to directly supplementing Dex to the medium. Furthermore, we demonstrated that Dex release kinetics can be modulated using surface modifications with supported lipid bilayers. Together, these data demonstrate that MSN films represent an interesting approach to create biomaterial interfaces with controllable biomolecule release and surface properties to improve the bioactivity of biomaterials.