Enhanced Cell Proliferation and Osteogenesis Differentiation through a Combined Treatment of Poly-L-Lysine-Coated PLGA/Graphene Oxide Hybrid Fiber Matrices and Electrical Stimulation

Bone tissue engineering scaffold provides an effective treatment for bone defect repair. Biodegradable bone scaffold made of various synthetic and natural materials can be used as bone substitutes and grafts for defect site, which has great potential to support bone regeneration. Regulation of cell-scaffold material interactions is an important factor for modulating the cellular activity in bone tissue engineering scaffold applications. Thus, the hydrophilic, mechanical, and chemical properties of scaffold materials directly affect the results of bone regeneration and functional recovery. In this study, a poly-L-lysine (PLL) surface-modified poly(lacticco-glycolic acid) (PLGA)/graphene oxide (GO) (PLL-PLGA/GO) hybrid fiber matrix was fabricated for bone tissue regeneration. Characterization of the resultant hybrid fiber matrices was done using scanning electron microscopy (SEM), contact angle, and a material testing machine. According to the results obtained from the test above, the PLL-PLGA/GO hybrid fiber matrices exhibited high wettability and mechanical strength. The special surface characteristics of PLL-PLGA/GO hybrid fiber matrices were more beneficial for protein adsorption and inhibit the proliferation of pathogens. Moreover, the enhanced regulation of MC3T3-E1 cell proliferation and differentiation was observed, when the resultant hybrid fiber matrices were combined with electrical stimulation (ES). The cellular response of MC3T3-E1 cells including cell adhesion, proliferation, alkaline phosphatase (ALP) activity, calcium deposition, and osteogenesis-related gene expression was significantly enhanced with the synergistic effect of resultant hybrid fiber matrices and ES. These data indicate that the PLL-PLGA/GO hybrid fiber matrices supported the cellular response in terms of cell proliferation and osteogenesis differentiation in the presence of electrical stimulation, which could be a potential treatment for bone defect.