Biomimetic Self-Templating: A Biomimetic Approach to Synthesis of Biological and Optical Materials

A fundamental challenge in nanotechnology research is to simultaneously synthesize high performance nanomaterials and to assemble them into well-defined, large-scale devices in a cost-effective manner. One approach to tackle this challenge is to learn from and adopt nature’s strategies (biomimetics) to design innovative engineering materials. Nature is a potent source for inspiration because, through millions of years of evolution, remarkably effective and efficient hierarchical structures have emerged to meet a variety of functions. Surprisingly, a single type of helical macromolecule (e.g., collagen) is often found to form diverse, functional structures (e.g., cornea, skin, and bone) when self-templated under different conditions. Based on this observation, in this study, we present an innovative biomimetic approach to synthesis of functional hierarchical structures based on directed evolution and self-templating. We utilize the bacterial virus M13 phage as a model helical macromolecule. First, we demonstrate a single-step process to create long-range-ordered supramolecular film showing multiple levels of hierarchical organization and helical twist. Both chiral liquid crystalline phase transitions and competing interfacial forces at the interface are found to be critical factors in determining the morphology of the structures during assembly. The resulting materials show potentials as optical materials (e.g., optical filters, structural color matrices) and biological materials (e.g., soft and hard tissue guiding scaffolds). This self-templating approach provides insight into the complexities of hierarchical assembly in nature and could be expanded to other chiral molecules for further engineering of sophisticated functional structures.