Inverted Colloidal Crystals as Tissue Engineering Scaffolds

Three-dimensional (3D) geometry actively regulates the growth of cells, communication among cells, and interactions between cells and the matrix, as well as cell differentiation pathways. Until now various methods have been utilized to generate a 3D synthetic scaffold, but rarely uniform and ordered structure could be achieved, though it has great advantages. In the course of our study, a new type of scaffold with controlled 3D organization of the pores has been developed. [1,2] Highly ordered colloidal crystal “template” has been prepared from 100μm diameter polystyrene beads using modified methods of colloidal crystal preparation conventionally utilized for photonic materials synthesis. With respect to engineering, the architecture of inverted opals can significantly reduce the mass transport resistance around it. Also, three-dimensionally ordered uniform size of pore structure makes it possible to understand effects and conditions of 3D contacts on cell development in systematic fashion. Colloidal crystal scaffolds were prepared from sol-gel and polymerization methods. To test the 3D geometry effect and biocompatibility of the scaffold, human promyeloblast HL-60 and human thymus Hs202.TH cell lines were accessed.