氧化石墨烯 / 壳聚糖复合涂层影响成骨细胞的生物学行为.

BACKGROUND: As a coating material, chitosan can effectively improve biological properties of medical metal surfaces due to its excellent film-forming and metal binding abilities. However, the biological activity and osteoinductive ability of chitosan are insufficient. Graphene oxide can improve the mechanical properties and biocompatibility of various polymer materials, as well as promote osteogenic differentiation. The combination of chitosan and graphene oxide may have better biological properties and osteogenic activity. OBJECTIVE: To construct the graphene oxide-modified chitosan composite coating material, analyze the surface morphology, chemical composition, and physical properties of the coating material, as well as the effects of the coating materials on proliferation, adhesion, and osteogenic differentiation of osteoblasts. METHODS: The titanium surface was treated with 3-aminopropyltriethoxysilane to form silane groups on the surface, and then glutaraldehyde was used to cross-link chitosan with silane groups to prepare simple chitosan coating and graphene oxide/chitosan composite coating, respectively. The surface morphology, chemical structure and hydrophilic properties of the coatings were characterized by atomic force microscopy, scanning electron microscopy, Fourier transform infrared spectroscopy, and contact angle measurement system. Rat osteoblasts were seeded on the surface of the two materials, and the proliferation, spreading, and osteogenic differentiation of rat osteoblasts were analyzed by CCK-8 assay, scanning electron microscopy, and reverse transcription-polymerase chain reaction analysis. RESULTS AND CONCLUSION: (1) The thickness of the graphene oxide sheets was about 2 nm as measured by atomic force microscopy; the scanning electron microscopy showed that the surfaces of both coatings were smooth and dense, in which the chitosan molecules were closely arranged and the graphene oxide was uniformly distributed in the chitosan, while wrinkles appeared on the surface of chitosan due to the addition of grapheme. The contact angle of the graphene oxide-chitosan composite coating was significantly smaller than the chitosan coating alone (P < 0.05). (2) CCK-8 assay showed that the graphene oxide-chitosan composite coating better promoted the proliferation of osteoblasts compared with the chitosan coating alone. (3) The scanning electron microscopy showed that better spreading was found in osteoblasts on the surface of the graphene oxide-chitosan composite coating compared with the chitosan coating alone. (4) Reverse transcription-polymerase chain reaction analysis showed that the mRNA expression of alkaline phosphatase and Runx2 was significantly increased in the graphene oxide/chitosan composite coating group compared with in the chitosan coating alone group (P < 0.05). (5) These findings suggest that graphene oxide/chitosan composite coating had good biocompatibility, physicochemical, and osteoinductive properties. [ABSTRACT FROM AUTHOR]