Surface-Initiated, atom transfer radical polymerization and pattern generation for controlled cell culture

Abstract

This thesis suggests the methods of surface chemical modification for controlled cell culture on the solid substrates. Surface-initiated, atom transfer radical polymerization (SI-ATRP) was utilized as the method of chemical functionalization, and NIH 3T3 fibroblast cells were cultured for cell micropatterns. First work describes a method to fabricate the dual functionalized surface, which is suitable for controlling cell adhesion and detachment. The surface is prepared with non-biofouling poly(oligo(ethylene glycol) methacrylate) (pOEGMA) and thermoresponsive poly(N-isopropylacrylamide) (pNIPAAm) polymeric brushes on the photolithographic patterned substrate via SI-ATRP. Then, NIH 3T3 fibroblast cells were seeded and cultured to the dual functionalized surface to investigate the cell behaviors. The cells adhered to the only pNIPAAm polymeric brush and the cell micropatterns were successfully generated. The cell adhesion and detachment was manipulated with respect to the thermoresponsive properties of the polymeric brush: the cells adhered to the surface at 37oC (above low critical solution temperature (LCST) of 32 oC), and detached at 21 oC (below the LCST). The generalized method for polymeric functionalization of inactive organic substrates via surface-initiated, atom transfer radical polymerization (SI-ATRP) is described in second work. Polycarbonate and polyethylene terephthalate (PET) were selected as the model organic substrates. The initiator of SI-ATRP was spin coated on the organic substrates, and then cured by UV irradiation. After the photoreaction of the initiator, succinimidyl carbonate-poly(oligo(ethylene glycol) methacrylate) (SC-pOEGMA) polymeric brush was grafted from the initiator-coated substrate. To develop a general method for the surface functionalization of organic substrates with bioactive molecules, SC-OEGMA was synthesized. As SC-OEGMA has both non-biofouling moiety and the reactive moiety (disuccinimidyl), we can directly bind the...