Synthesis of bio-inspired nanomaterials for tissue engineering

Abstract

Engineering surface properties of scaffold materials is a critical step for tissue engineering because such properties significantly influence cellular behaviors, such as adhesion, proliferation, migration, and differentiation. Among many parameters that affect cell-material interactions, surface chemistry and topography are major factors to be considered in the design of scaffold materials that mimic chemical and physical features of microenvironments in native tissues. In this thesis, mussel-inspired polydopamine functionalization of scaffold materials was studied for the investigation of adhesion, proliferation, and differentiation of mammalian cells such as osteoblasts, endothelial cells, and myoblasts. The effect of scaffold topography on cell-material interactions was also examined in combination with surface chemistry of substrates. Moreover, the applicability of carbon nanomaterials (e.g., graphene oxide, reduced graphene oxide) to tissue engineering is discussed. Chapter 1 and 2 describe a versatile route for promoting cell adhesion and viability on various non-wetting surfaces, inspired by mussel adhesion mechanism. The oxidative polymerization of dopamine, a small designer molecule of the DOPA-K motif found in mussels, results in the formation of polydopamine ad-layer on any material surface. Chapter 1 shows that polydopamine coating can enhance cell adhesion on any type of material surfaces including anti-adhesive substrates. Mammalian cells well adhere and undergo general cell adhesion processes (i.e., attachment to substrate, spreading, and cytoskeleton development) on polydopamine-modified surfaces, while they barely adhere and spread on unmodified non-wetting surfaces. In Chapter 2, the spatial control and patterning of mammalian cells are achieved by combining the non-adhesive property of hydrophobic substrates and the adhesive property of polydopamine. The cells align in the direction of striped polydopamine patterns, and this tendency is not...