Dragonflies, diseases and sterilised surfaces

A noticeable side-effect of the COVID-19 pandemic is everyone’s hyper-awareness of surface cleanliness. To combat surface germs in general, dragonflies have become an inspiration to research scientists with recent antimicrobial nanocoatings aiming to replicate the incredibly sterile surfaces of dragonfly wings.

"Dragonfly" by S Hooper via Flickr
“Dragonfly” by S Hooper via Flickr

What are nanocoatings?

Nanocoatings form a thin layer of nanoparticles once applied to surfaces. The coatings differ in composition according to the purpose for which they are designed. They are commonly applied to vehicles in order to make them resistant to dirt, water and scratching. However, their abilities reach far beyond the upkeep of people’s cars. They are incredibly useful in a range of industries, and to date have been tailored to assist in food, health and construction workplace environments. Their properties can include weather and UV ray protection as well as chemical and oil resistance. Further research and mass production of these nanocoatings is predicted to exceed $9.7 billion per year after 2025. This highlights their potential contributions to society many are anticipating.

The dragonfly wing model

Past research shows that dragonfly wings have antimicrobial properties, keeping the dragonflies protected from unwanted diseases. Bacteria, viruses and fungal spores, among other harmful organisms are classified as microbes. The wings were found to be covered in small, pointed structures, formally known as nanopillars. These nanopillars pierce the cell walls of bacteria unfortunate enough to land on them, which ultimately leads to their destruction. These findings prompted researchers to attempt replicating the surface of dragonfly wings in the form of a nanocoating. Researchers cleverly constructed the nanopillars out of zinc oxide, which is an antimicrobial, yet non-toxic material. Conveniently, these zinc oxide nanopillars also excrete other useful particles into their surrounding atmosphere, which can destroy bacteria present nearby. Dr. Yugen Zhang produced and tested the zinc oxide nanocoating on a range of materials, including ceramic, glass and textile surfaces. It was found that the nanocoated surface killed 99.9% of bacteria it came into contact with. What a promising result!

Future applications

An issue of great concern that has arisen from typical antibacterial treatment is the bacteria’s growing resistance to it. Over-prescription of medicines such as antibiotics has seen a dramatic increase in ‘superbugs’. With over 700,000 people dying per year from drug-resistance bacterial infections, we are in desperate need of a treatment that will not give the bacteria an opportunity to develop a resistance. Good thing that zinc oxide nanocoatings do just that!

Ideally, this nanocoating would be used like a standard surface sanitising spray, and be administered to frequently touched surfaces in public spaces, particularly hospitals and doctors’ clinics. Since bacteria, viruses and fungal spores can adhere to surfaces, it is no surprise to learn that 80% of regular infections are transmitted by people’s hands.

Looking to the future, the benefits that nanocoatings could offer society really are phenomenal. And to think this brilliance was based off the wings of a dragonfly! It makes me wonder what other remarkable features nature has in store that are yet to be discovered.

4 Responses to “Dragonflies, diseases and sterilised surfaces”

  1. eewent says:

    Nanocoatings seem like a very interesting idea and hopefully it can become applicable sometime in the near future. Thanks for the post I learned a lot of new things!

  2. Alysha Caruso says:

    Thanks Tom and George!

  3. George Mechaalani says:

    Hi Alysha! Really interesting post I learned new concepts I was unaware of!

  4. Tom Roads says:

    Great post Alysha! Always interesting to see what we can learn from pre-existing systems in nature!