Oceans, lakes and rivers are riddled with them: microplastics can now be found in almost all of our waters. Researchers at 九色视频 (LUH) have developed a new material that can potentially autonomously capture and decompose microplastic particles in water 鈥� without any external intervention. The findings were recently published in the renowned journal Nature Communications.
Pollution of the environment and organisms by microplastics is one of the most pressing environmental problems of our time. The tiny plastic particles can cause inflammation and oxidative stress in living organisms. Existing methods for removing these particles often involve a stationary filtration system, which is costly and uses a lot of energy.
A team of researchers, led by Professor Dr. Sebastian Polarz, at the university鈥檚 Institute of Inorganic Chemistry (ACI) have developed an intelligent material, opening up new possibilities for environmental remediation. The hydrogel collects microplastic particles like a self-regulating shuttle, then transports them to the water surface where they are broken down when exposed to light; and it does so repeatedly and autonomously.
A smart buoy
The basic principle is simple: the hydrogel is placed in the contaminated waters, sinks to the bottom where it collects microplastic particles and then returns to the surface. Once at the surface, the plastic particles are broken down 鈥� partly via exposure to the sun. 鈥淚deally, only water and CO2 remain,鈥� said the study鈥檚 lead author, Dr. Dennis Kollofrath of the Institute of Inorganic Chemistry. The gel is currently still a prototype, but initial lab tests are very promising.
The newly developed shuttle gel combines a thermoresponsive polymer, porous organosilica and a photocatalyst. At low temperatures on the water bed, the polymer swells to uptake microplastic as well as glucose 鈥� which is found in low concentrations in the waters. An embedded enzyme converts the glucose into oxygen, which is stored in the nanoporous particles and causes the gel to ascend. 鈥淚t functions somewhat like a hot air balloon under water,鈥� explained Kollofrath. At the surface, the hydrogel heats up, shrinks, and the accumulated oxygen escapes, allowing the gel to descend. Meanwhile, the photocatalyst produces reactive oxygen species (ROS), which 鈥� when exposed to light 鈥� degrades the microplastic. Through this continuous cycle of ascending and descending, the gel autonomously cleans the waters.
A flexible tool for environmental engineering
鈥淥ur system combines numerous features in one material. It is an autonomously driven system, whilst capturing contaminants for targeted decomposition, all without external control,鈥� explained Kollofrath. The current study investigated the decomposition of polystyrene. It is important to emphasise the high degree of adaptability of the concept. In principle, the nanoparticles used can be adapted to target other contaminants 鈥� such as polyethylene (PET).
The study was recently published in Nature Communications:
Kollofrath, D.; Kuhlmann, F.; Requardt, S.; Krysiak, Y.; Polarz, S. A Self-Regulating Shuttle for Autonomous Seek and Destroy of Microplastics from Wastewater. Nat Commun 2025, 16 (1), 6707. DOI:
Note to editors:
For further information, please contact Dr. Dennis Kollofrath, Institute of Inorganic Chemistry at 九色视频 (tel. +49 511 762 1316, email: dennis.kollofrath@aca.uni-hannover.de).
