Indonesian scientists have found a way to convert plastic bags into nanoparticles that can detect toxic metals in drinking water, combining the fight against environmental pollution with the protection of human health.
Chemists at Gadjah Mada University in Yogyakarta, led by Dr. Indriana Kartini, have developed innovative technology to convert used polyethylene bags into Carbon Quantum Dots (CQDs)—nanoparticles capable of detecting toxic metals in drinking water.
The global community faces a massive problem of plastic pollution: millions of tons of waste enter the environment annually and take centuries to decompose. Traditional recycling is no longer sufficient, so the Indonesian team focused on upcycling—transforming waste into a high-value resource.
To create the nanoparticles, the scientists used modified pyrolysis combined with hydrothermal treatment. By using less than 7% hydrogen peroxide, the entire process took only 10 hours. The resulting CQDs emit a bright glow under UV light and remain stable during storage, sun exposure, and high salt concentrations.
The most impressive property of the new nanoparticles is their ability to detect iron ions (Fe3+) in water. Thanks to oxygen-containing chemical groups on their surface, they selectively bind to pollutants and function as precise sensors. In tests, the detection limit was a mere 9.50 micromoles, with almost perfect measurement accuracy (R2=0.9983).
The developed sensors are easy to use, portable, and affordable. They could become an indispensable tool for communities without modern laboratory equipment, enabling quick water quality monitoring.
According to the project’s authors, this work is not only a step toward solving the plastic pollution problem but also a clear example of the circular economy, where waste is transformed into a resource for creating life-saving technologies.
The research results were published on July 3, 2025, in the journal Carbon Research.
