Large-Scale Artificial Production of Coleoptera Cuticle Iridescence and Its Use in Conformal Biodegradable Coatings

In this study, bioinspired chitinous manufacturing is leveraged to artificially reproduce iridescent gratings found in the cuticles of beetles living in concealed environments. Combining this with a melanin-like background achieves a vibrant iridescence, similar to that produced by the multilayer reflectors in leaf beetles. In this process, the controlled production of optical structures is allowed using chitinous polymers, the same components that produce color in arthropod cuticles. This not only aids in understanding the functionality and evolutionary advantages of these structures without being limited to the existing solutions in animals-which entangle the solutions for several problems with the rubble of past functionalities-but also enables the creation of color with the second most abundant organic material on Earth, only surpassed in its ubiquity by cellulose. However, unlike cellulose-based materials, the chitinous optical structures are produced by avoiding the use of strong organic solvents, representing a simplified approach to producing vibrant, iridescent, fully biodegradable, and ecologically integrated colors. Herein, the production of hundreds of square centimeters of iridescent chitinous surfaces, a scale suitable for imparting biodegradable color to large 3D objects, is demonstrated. In this study, a bioinspired manufacturing process is presented reproducing vibrant, iridescent colors in beetle cuticles using their native chitinous polymers. In this process, the multifunctional optimization found in nature is mimicked, resulting in a fully biodegradable and ecologically integrated color. The large-scale production capability of this method opens up potential applications in conformal coatings for 3D objects.image (c) 2024 WILEY-VCH GmbH