Fabrication of bone surface mimicked biodegradable chitosan - graphene oxide nanocomposite membrannes

Abstract

Biomaterials and tissue engineering applications are promising to heal defected bone tissue. Direct interaction of cell and biomaterial surface occurs and surface properties are able to change cellular responses. In this thesis, it was aimed to fabricate chitosan (CH) and graphene oxide (GO) based biodegradable membranes, which are able to mimic natural bone surface topography. Micro and nanostructures of bone surface was copied by soft lithography technique with using polydirnethylsiloxane(PDrviS). Human osteoblast cells (hFOB 1.19) were used to evaluate effects of surface topography and GO addition. Surfaces were modified with hydroxyapatite {HA) nanoparticles to enhance osteoconductivity. Physical and chemical characterization of membranes was performed by scanning electron microscopy, confocal microscopy and spectroscopy techniques. SEtvi and confocal microscopy imaging of membranes showed that bone surface topography mimicked, successfully. Spectroscopy techniques, namely FT-IR, XPS, Raman and XRD demonstrated chemical compositions of CH, GO and HA modification. hFOB cell morphology was evaluated by using SEM at day 7. HA modification and bone surface mimicking provided more surface area, so that spread of cell was increased and surface of membranes covered with the cells. In addition , ~ addition had positive impact on cell spreading when it is compared with pure CH. ~I viability was analyzed by performing !!\ITT assay. Tho obtained results demonstrated that cell viability increased in bone surface mimicked membranes.|Keywords : Biomimetic, Bone Surface rviimicking, Human Osteoblast, Soft LithogTaphy, Chitosan, Graphene Oxide, Hydroxyapatite.