Enhanced proliferation and osteogenic differentiation of MC3T3-E1 pre-osteoblasts on graphene oxide-impregnated PLGA-gelatin nanocomposite fibrous membranes

Currently, combining biodegradable polymeric scaffolds with living cells for bone repair has received significant attention. Ideal bone tissue engineering scaffolds should be biocompatible, biodegradable, and mechanically robust and have the ability to regulate cell function. The aim of this study was to fabricate graphene oxide-impregnated poly(lactic-co-glycolic acid)-gelatin (GO-PLGA-Gel) nanofibrous matrices that stimulate osteoblast proliferation and differentiation for bone regeneration. The GO-PLGA-Gel nanofibrous matrices were comprised of interconnected continuous fibres with three-dimensional porous structure that were successfully fabricated via an electrospinning process. The morphology, surface properties, mechanical properties and chemical composition of nanofibrous matrices were characterized by SEM, ATR-FITR, XRD, a materials testing machine and water contact angle measurements. Subsequently, fluorescence staining and an MTT assay were utilized to observe the influence of the Gel and GO on the MC3T3-E1 cell proliferation and attachment in vitro. In addition, osteogenic differentiation was determined from the alkaline phosphatase activity (ALP), expression of osteogenic marker genes and alizarin red staining. The results demonstrated that the MC3T3-E1 cells attachment and proliferation on GO-PLGA-Gel nanofibrous matrices were much higher than on the pure PLGA nanofibrous matrices. More importantly, GO-PLGA-Gel nanofibrous matrices significantly increased the alkaline phosphatase activity (ALP), expression of osteogenesis-related genes and calcium deposition of MC3T3-E1 cells. Our data indicated that blending GO with Gel retained the osteogenesis nature of GO without negatively influencing the proliferation cell effect of the Gel. Therefore, it is concluded that the GO-PLGA-Gel nanofibrous matrices are versatile biocompatible scaffolds for bone tissue engineering.