Investigation of the effects of FMOC amino acids modifications to osteoblast behaviour on RGO/Ti surface

In this thesis, adhesion, proliferation and morphology of osteoblast cells on functionalized RGO/Ti surface were investigated. Firstly, amino-functionalization with 3-aminopropyl phosphonic acid (APA) molecules on Ti surface was carried out. Graphene oxide flakes were immobilized on APA/Ti surfaces through interaction between the epoxy groups of GO and the amine groups of APA molecules. Reduced graphene oxide flakes on APA/Ti surface were performed by using hydrazine monohydrate treatment. In order to enhance further surface bioactivity, Fmoc amino acids having different the hydropathy indexes modified on RGO/Ti surface by the π-π bond. The chemistry and morphology of unmodified and modified Ti surfaces were characterized by using Water Contact Angle (WCA) measurements, X-ray Photoelectron Spectroscopy (XPS), Raman Spectroscopy, Atomic Force Microscopy (AFM) and Scanning Electron Microscopy (SEM). According to characterization results, Ti surfaces were coated with GO and RGO, as well as the surface hydrophilicity was controlled by functionalization with Fmoc amino acids successfully. Then, cell viability, proliferation and morphology were examined by using the MTT, Alamar Blue Assays and SEM, respectively. The in vitro studies indicated that the surface chemistry and nanometric roughnesses on designed materials remarkably enhanced cell behavior, especially with respect to initial adhesion and proliferation. Consequently, the development of novel interface at cell/implant has a great potential for increasing osseointegration in the field of bone tissue engineering.