On the surface of the clanger cicada there are tiny cone-like structures known as nanopillars. These are spaced out among the wing and protrude upward from the surface. A recent study shows that these structures can help prevent bacterial growth by rupturing bacterial cells that are thin and soft enough to be torn upon stretching. The mechanism for doing so happens when a bacterial cell finds itself on the surface of the wing; as it settles in, the nanopillars push up against it causing the cell to somewhat mold around them. This shifting of shape causes stretching in the bacterial cell’s membrane. With enough stretch, the surface eventually begins to split and tear. Additional research will shed light on whether these nanopillar structures can be modified or combined with other antimicrobial technologies to work on bacteria with tougher membranes as well.
Check out this video for a simulation demonstrating how the nanopillars work: Biophysical model of the cicada wing nanopillar – Bacterial cell interactionsEdit Summary
“The nanopattern on the surface of Clanger cicada (Psaltoda claripennis) wings represents the first example of a new class of biomaterials that can kill bacteria on contact based solely on their physical surface structure. The wings provide a model for the development of novel functional surfaces that possess an increased resistance to bacterial contamination and infection. We propose a biophysical model of the interactions between bacterial cells and cicada wing surface structures, and show that mechanical properties, in particular cell rigidity, are key factors in determining bacterial resistance/sensitivity to the bactericidal nature of the wing surface. We confirmed this experimentally by decreasing the rigidity of surface-resistant strains through microwave irradiation of the cells, which renders them susceptible to the wing effects. Our findings demonstrate the potential benefits of incorporating cicada wing nanopatterns into the design of antibacterial nanomaterials.” (Pogodin et al. 2013:835)