Investigation of protein adsorption and cell behavior on laser textured titanium surfaces

When an implant introduced to the body, proteins in the blood stream cover the implant surface. That is how the body starts to recognizes foreign materials. The properties of surface plays critical role to predict the body response by understanding protein adsorption. Surface texturing using lasers is an effective and highly controllable surface modification technique. This thesis is focused on distinct surface patterns formed by microsecond and femtosecond lasers to observe the protein adsorption and cell behavior on titanium (Ti) surfaces. Ti has been chosen as the model biomaterial since it is a widely used material as a bone implant which mimics the bone structure in terms of strength and density. We hypothesized that periodic nano-morphology on Ti surfaces obtained using different laser sources will affect the protein adsorption, cell attachment and proliferation. The study has 4 aspects; surface modification, surface characterization, protein and cell culture studies. Surfaces had 3 patterns; polished (pTi), laser textured by microsecond laser (mTi) and by femtosecond laser (fTi).Surfaces were characterized in terms of wettability, roughness and topography. Protein amount and conformational changes of proteins were investigated. Adsorbed protein amount was higher on pTi compared to the other groups. Cytotoxicity and cell proliferation were examined. While cytotoxicity was not observed in results of indirect MTT assay, Ti samples showed cytotoxic effect in the results of direct MTT assay. fTi demonstrated significantly high proliferation rate compared to mTi and pTi. Cell morphology and alignment was investigated. As a result of this thesis, forming submicron patterns based on laser texturing significantly influences the protein adsorption, protein conformation, cell proliferation and cell morphology.