A Study of End-functionalized Polylactide based Thin Films for Biomedical Applications

The goal of the present work was to understand the important design factors for a nanostructured polylactide scaffold for tissue engineering. This work focused on two important design aspects of tissue engineering: Topography and Chemistry. The specific goal of the work was to understand how topography and chemistry (end functionalization of PLA) of scaffolds impacts cell attachment, growth and proliferation. This was achieved by spin-coating PLA and Ionomeric PLA on glass coverslips followed by thermal annealing of these thin films that resulted in scaffolds of varying topology and scale-size. The morphologies are expected to be a consequence of two competing phenomena, dewetting and crystallization. Nano-scale texturing produced with annealing did not influence cell behavior. Functional end-capping of PLA by ionic groups in ionomeric PLA enhanced osteoblast differentiation compared to the traditional PLA based materials; however, formation of mineral nodules was suppressed, possibly due to the ions. Since topography did not influence cell behavior in the first set of studies, influence of a different end functionalization was undertaken in the next. The possibility of cholesterol-a bioactive motif, in rendering PLA cell receptive was evaluated. Cholesterol end-functionalized PLA was synthesized by ring opening methods and then flat non textured films were evaluated for cell response. Also, annealing and texture formation experiments were performed for sake of our curiosity