Australasian Science: Australia's authority on science since 1938

How Deadly Dragonfly Wings Bust Bacteria

Scientists have revealed the intricate detail of how dragonfly wings kill bacteria by trapping bacteria in the more than 10 billion “nanofingers” lining their surface. “While trying to escape, the bacteria literally tear themselves apart,” says Dr Annalena Wolff of Queensland University of Technology. “The ‘fingers’ on the wings are so small that even one million of them, put side-by-side, would be only just as large as a wasp.”

The observation required the use of ion and electron microscopes but, in the past, these microscopes easily burnt biological material. However, Wolff developed new techniques to overcome this problem.

For researchers tackling deadly antibiotic-resistant bacteria, the dragonfly wing revelation offers potential new methods of dealing with the problem. “We have been working to unlock the secret of how dragonfly wing nanostructures destroy bacteria so that they could be actively mimicked to surfaces of next-generation smart materials, especially for use in medical applications,” says QUT colleague Dr Chaturanga Bandara. “Seeing the natural nanostructure and its bacterial interaction in 3D is providing us with new clues on such new surface designs”.

Wolff thinks the new images of the dragonfly wings’ nanostructures will help researchers to design things like new bacteria-busting surgical and hospital equipment. "The huge microscopes we work with are 2 metres tall and 2 metres wide and can take images of almost anything. We can use the same microscopes to build things. For example, rebuild the dragonfly wing 'fingers' using different materials or build robots so small that you could fit 64 billion of them in a single raindrop. You are only limited by your imagination.”