Modification of titanium surface for supporting osteoblast adhesion and differentiation

Abstract

Polyelectrolyte multilayer (PEM) film created via Layer-by-Layer deposition can be used to modify the surface properties of materials in order to improve cell-material interactions. In this study poly(diallyldimethylammonium chloride) (PDADMAC), poly(sodium 4-styrene sulfonate) (PSS) and poly(4-styrenesulfonic acid-co-maleic acid) sodium salt (PSS-co-MA) were assembled into PEM {(PDADMAC/PSS)4/PDADMAC+PSS-co-MA} film on glasses, titanium (Ti) discs and polycaprolactone (PCL) films. PSS-co-MA PEM film coated substrates had better wettability property than uncoated substrates. The effects of PSS-co-MA PEM surface on murine pre-osteoblastic cells (MC3T3-E1) and human primary osteoblastic cells were examined. Results showed that PSS-co-MA PEM film coated substrates promoted osteoblast differentiation. In this regard, the increase of alkaline phosphatase activity, osteoblastic mRNA expressions (type I collagen, osteopontin, bone sialoprotein, osteocalcin and dentin matrix protein 1), osteocalcin protein secretion and calcium deposition rate were noted compared to uncoated substrates. To test bone induction ability in vivo, PSS-co-MA coated PCL films were implanted in murine calvarials defects. Result showed an increased amount of new bone formation around the PSS-co-MA coated PCL films compared to uncoated PCL. In conclusion, PSS-co-MA film enhanced osteoblast differentiation and could be used to promote mineralization in bone tissue engineering and to improve osseointegration for dental implants.