A pioneering method for detecting harmful nanoplastics has been developed by researchers at the University of Melbourne and the University of Stuttgart. This novel optical sieve technology promises to revolutionize the monitoring of plastic pollution, offering affordable and portable solutions for global health and environmental science.
Researchers have developed a groundbreaking method for detecting nanoplastics, offering a cost-effective and portable solution with the potential to significantly impact global environmental health monitoring. This innovative technology, developed by an international team from the University of Melbourne and the University of Stuttgart, represents a major step forward in understanding and addressing the pervasive issue of plastic pollution.
Nanoplastics, even smaller and more insidious than microplastics, pose serious risks as they infiltrate food, water and human tissues. Detecting these minute particles has long proven challenging and expensive, often requiring sophisticated equipment like scanning electron microscopes.
In a paper published in Nature Photonics, the researchers introduced an “optical sieve” technology. This novel approach, which uses a gallium arsenide microchip with an array of tiny cavities, can detect, classify and count nanoplastic particles in real-world environments.
Lukas Wesemann from the University of Melbourne, who led the research on the Australian side, emphasized the profound impact of this development.
“Until now, detecting and sizing plastic particles with diameters below a micrometer – one millionth of a meter – has relied on costly tools such as scanning electron microscopes, and been nearly impossible outside advanced laboratories, leaving us blind to their true impact,” Wesemann said in a news release. “Our novel optical sieve is an array of tiny cavities of varying sizes in a gallium arsenide microchip.”
The optical sieve works by capturing plastic particles in voids matching their size as a liquid containing nanoplastics is poured over it. Particles are sorted into categories down to a 200-nanometer diameter.
“Crucially, it requires only an optical microscope and a basic camera to observe distinct color changes to light reflecting off the sieve, which allows us to detect and count the sorted particles,” Wesemann added.
Co-author Brad Clarke, an associate professor at the University of Melbourne, highlighted the accessibility and affordability of this innovation for pollution monitoring.
“Understanding the numbers and size distribution of nanoplastics is crucial to assess their impact on global health, and aquatic and soil ecosystems,” he said in the news release. “Unlike microplastics, smaller nanoplastics can cross biological barriers – including the blood-brain barrier – and accumulate in body tissues, raising profound health concerns of toxic exposure.”
The team validated their new technique using lake water mixed with nanoplastics and plans future tests, including identifying nanoplastics in blood samples. Unlike existing methods, this approach does not require separating plastics from biological matter, Wesemann explained.
The researchers are now exploring ways to scale this innovation into a commercially available environmental testing solution. This potential commercialization could make widespread monitoring more feasible.
Source: University of Melbourne