Bacteria (Streptococcus mutans) highlighted in green resting on a cicada wing's microscopic structures. Credit:Jolanda Watson It was against the "deafening sound" of cicadas chirping early summer nearly 20 years ago that the couple – who share a birthday and many interests – went from "hate at first sight" to a partnership in the lab and then at home. Together they have helped put Australia at the forefront of research using the unique properties of cicadas to fight antibiotic-resistant bacteria. "We would walk around the campus, and pick up anything that looked interesting and put it under the microscope," Greg said. They were often "rained upon from above" by cicadas. "We'd often just find a wing, and we'd think the microbes and the environmental attack is much stronger on the body. If the wings are still intact, they must have some microbial resistance," he said.

Dr Gregory Watson and Dr Jolanta Watson looking at a cicada under an atomic force microscope. Credit:Courtesy Discovery Magazine Under an atomic-force microscope, which can view tiny topographies​ only a few atoms in height, the scientists now at the University of the Sunshine Coast made some surprising discoveries. The couple weren't the first to discover the wings were non-reflective, but they became fascinated with why. This led them to discover the wings' structure made them resistant to bacteria and other contaminants. They experimented with liquids, solids, contaminants and pollens to see how the wings cleaned themselves. "Cicadas have different bumps, some have big bumps, some have little bumps [including the common green grocer]," they said.

Their current research concludes the width of each of the nanoparticles or nano spikes, and the size of the space between them, is key to how they resist bacteria. Each spike is about one thousandth of the thickness of a human hair. When Professor Elena Ivanova​, a scientist in Victoria who won this year's Eureka Prize, was looking for information on antibacterial surfaces, she wrote to the Watsons. They provided her with their wing samples. In the lab pathogen Pseudomonas aeruginosa settle on the wings, but within three minutesare dead. "Under the microscope, the nanoscale pillars of the cicada wing seem to have punctured the cell walls of the bacteria, causing their innards to spill out and leading to a quick death," reported American network PBS who recently documented this research. "Ivanova and her colleagues added a couple of fluorescent dyes to the wing's surface that bind to the DNA inside bacteria, glowing red in those that have punctured membranes and green in those that are healthy. Under their bench-top microscope, the surface looked like a bloody battle had just taken place," said PBS's Alex Riley.

It was the first reported example of a naturally existing surface with a physical structure that exhibits such effective bactericidal properties," a paper by the Watsons with Professor Ivanova in 2013 said. "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 its physical surface structure," they said. Only last month Professor Ivanova and Professor Saulius Juodkazis won the prestigious 2017 UNSW Eureka Prize for Scientific Research. They replicated these surface patterns on a nanomaterial constructed out of metallic materials with tiny self-sterilising protrusions. They are now working with an implant manufacturer in the hope of engineering an anti-microbial nanosurface onto artificial joints to prevent infections they say affect millions. They also plan to fabricate nanostructures based on the cicada and dragonfly (which has similar properties) on non-metallic surfaces such as plastic, ceramics, glass and silicon. These could be used for anything from pathogen-proof paint to infection-resistant water filtration systems. The Watsons, too, are aflutter with ideas – they are just completing a paper that suggests uses for cicada wings from micro-ribbons that clean the bloodstream to cleaning water in the middle of Africa. "It is only limited by your imagination," said Jolanta.