This post was originally published on here
The detailed observation of nature can reveal brilliant solutions for science. This was the case with the wings of the Empress cicada, which hide a nanoscopic network capable of transforming chemical and biological detection.
Thousands of microscopic spirals cover each wing of the insect and, when coated with silver, allow the SERS (Surface-Enhanced Raman Spectroscopy) technique to capture previously invisible signals with surprising precision.
A discovery with global impact
The discovery, published in the journal AIP Advances, could revolutionize the manufacturing of sensors by enabling more sensitive, economical, and sustainable molecular devices. Its applications range from medical diagnostics to environmental controls, expanding access to detection technologies worldwide.
The study was led by the scientist Chung-Hung Hong, along with teams from the China Medical University and the National Taiwan University.
The Empress cicada and its unique structure
This insect of the order Hemiptera, known for its translucent wings and summer song, inhabits regions of Asia. Its wing structure not only fulfills biological functions but also inspires developments in nanotechnology, thanks to the regular arrangement of microscopic columns on its surface.
For years, detecting small molecules or traces of contamination has required specialized and expensive optical sensors. Raman spectroscopy, the basis of these devices, demands complex nanostructures and costly materials, limiting its widespread application in hospitals or environmental monitoring.
Nature as a template
Faced with this challenge, the researchers took advantage of the natural geometry of the wings as a ready-to-use template. They applied a thin film of silver using two techniques:
- Sputtering.
- Electron beam evaporation.
Each method generated different columns (cylindrical or conical). The team sought the perfect thickness of silver and discovered that a five-nanometer separation between cylindrical pillars produces the greatest SERS effect.
This spacing creates “hot spots” where the electromagnetic field is concentrated, multiplying the detected signal. The intensity obtained was up to a million times greater than that of a wing without silver, positioning this technology as a benchmark in ultrasensitive optical detection.
Future applications
The researchers noted that the method could be extended to surfaces inspired by other species, such as butterflies or leaves, making it more sustainable and scalable. The wings of the Empress cicada could inspire sensors that work at different wavelengths, even beyond visible light, allowing the detection of pathogens or pollutants in various environments.
The team estimates that this advancement could “open a new path towards sustainable, low-cost, and highly sensitive detection technologies,” expanding access to scientific innovations.
Challenges and conclusions
The use of biological materials involves challenges, such as the natural variability in size or shape, and the need to adapt other natural surfaces. However, the research demonstrates that biological nanostructures can guide scientific and engineering advances.
The conclusion is clear: science and nature can walk together towards new tools for health and planet care, inspiring innovative solutions from the invisible patterns of an insect.
