Mediating Mesenchymal Stem Cells Responses and Osteopontin Adsorption via Oligo（ethylene glycol）-amino Mixed Self-assembled Monolayers

Oligo（ethylene glycol） （-OEG） and amino （-NH2） mixed self-assembled monolayers （SAMs） were employed as model substrates to investigate the effect of charge density on the fate of mesenchymal stem cells （MSCs） and osteopontin （OPN） adsorption. We found that all surfaces presenting -NH2 groups favored cell responses regardless of the surface charge. Meanwhile, OPN adsorption could remain stable on the mixed SAMs over a certain range of charge densities. Our work provides some insights into cell responses and protein adsorption to surface charge.