By controlling the interaction of nano-scale building blocks, nature produces highly complex architectures using only biopolymers and self-assembly routes. Inspired by such biological nanostructures [1-2], the possibility to design materials at the nano-scale by guiding the hierarchical self-assembly of its constituent components is an attractive route for rationally-designed, sustainable manufacturing of optical material [3-6]. Within the large variety of biological building blocks, polysaccharides are between the most promising bio-sourced materials, primarily for their abundance, biocompatibility and ability to readily organize into photonic structures. Here, we review some examples complex and hierarchical photonic structures found in nature and we illustrate the fabrication process to produce scalable novel photonic structures using low cost materials in ambient conditions.
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