Antibacterial Structure on the wings of Cicadas and Dragonflies
A group of scientists in Australia and Nigeria , who observed the ability to kill E.coli bacteria on the wings of the dragonfly Orthetrum villosovittatum, proposed the bactericidal mechanism of the dragonfly wings according to the following diagram:
The upper row (figures a, b, c, d) depicts nanopillars that penetrate the bacterial cell membrane and leak cytoplasm on the cicada's wings. In the lower row (figures e, f, g, h) depicts dragonfly wings with nanopillars of unequal height, when the bacteria move, the higher force of adhesion on the nanopillars will tear the microscopic cell membrane.
Picture a: Orthetrum villosovittatum dragonfly wings under a microscope
Figure b: Cross section of dragonfly wing Orthetrum villosovittatum
Another group of scientists in Australia also observed the ability to kill the green latex bacillus Pseudomonas aeruginosa on the wings of the cicada Psaltoda claripennis .
The bacterial cells pierced by the nanopillars can be clearly seen in images a and b. Image c shows the bactericidal ability of cicada wings over time with live bacterial cells stained blue, dead bacterial cells stained red and yellow.
These studies and observations form the basis for the development of resistant, bactericidal surfaces, which will be useful to medicine as today's bacteria have adapted to and are resistant to antibiotics. And this is also the reason why the wings of cicadas and dragonflies are always clean.
Source of information:
 Bandara, C. D., Singh, S., Afara, I. O., Wolff, A., Tesfamichael, T., Ostrikov, K., & Oloyede, A. (2017). Bactericidal Effects of Natural Nanotopography of Dragonfly Wing on Escherichia coli. ACS Applied Materials & Interfaces, 9(8), 6746–6760.doi:10.1021/acsami.6b13666.
 Ivanova, E. P., Hasan, J., Webb, H. K., Truong, V. K., Watson, G. S., Watson, J. A., … Crawford, R. J. (2012). Natural Bactericidal Surfaces: Mechanical Rupture of Pseudomonas aeruginosa Cells by Cicada Wings. Small, 8(16), 2489–2494.doi:10.1002/smll.201200528.
Translated by Phuong Huyen
Link to Vietnamese version