Preparation and characterization of bovine serum albumin nanoparticles modified by Poly-l-lysine functionalized graphene oxide for BMP-2 delivery

Abstract

The development of bioactive carrier with controlled delivery of Bone morphogenetic protein (BMP-2) is an important part in bone regeneration. Our study fabricated novel modified nanomaterials based on poly-l-lysine functionalized graphene oxide (GO-PLL) and explore its potential applications for BMP-2 delivery. GO-PLL was used to modify BMP-2 encapsulated bovine serum albumin (BSA) nanoparticles (GO-PLL/BMP-2) by self-assembling technology. The physiochemical and biological properties of GO-PLL modified BSA nanoparticles were investigated in vitro. Additionally, rabbit calvarial bone defects were created to investigate bone formation ability in the presence of GO-PLL/BMP-2 loaded alginate/gelatin scaffolds. The results suggested BSA particles were spatially interacted with GO-PLL complexes by strong electrostatic attraction. When compared with BMP-2 encapsulated BSA nanoparticles, a pronounced decrease in BMP-2 gentle release was observed in the presence of GO-PLL/BMP-2 nanoparticles, and extended to over 14-day release periods. More importantly, GO-PLL/BMP-2 nanoparticles significantly enhanced alkaline phosphatase activity (ALP) and matrix mineralization, and exhibited favorable bone formation ability when loaded into alginate/gelatin scaffolds. These results demonstrated that PLL functionalized GO complexes are considered as appropriate delivery system for BSA modification, and have great potential for BMP-2 delivery in bone regeneration.

Keywords

• Graphene oxide
• Poly-l-lysine
• Bone morphogenetic protein-2
• Osteogenesis
• Nanoparticles