Method for removing microplastics from water could also speed up blood analysis
Researchers have demonstrated a way to speed up and potentially scale up the process of particle separation in liquids. This could be used, for example, to study microplastics in drinking water or even to analyze cancer cells in the blood.
In a report in the journal Nature Microsystems & Nanoengineering, a team led by researchers at the KTH Royal Institute of Technology described a faster and more precise method of elastoinertial microfluidics, which controls the movement of tiny particles in fluids by exploiting both the elastic properties of the fluid and the forces acting as the fluid moves.
Selim Tanriverdi, a PhD student at KTH and lead author of the study, says the improved technique offers a wide range of potential applications in medical testing, environmental monitoring and manufacturing. The method could help quickly sort cells or other particles in blood samples, remove contaminants from water for analysis, or enable the development of better materials by separating different components more efficiently, he says.
The microfluidic device consists of specially designed channels that can process relatively large volumes of liquid quickly, making it perfect for applications that require rapid and continuous separation of particles, says Tanriverdi. Within these channels, particles can be sorted and aligned – a crucial step that is critical for separating different particle types.
The improved accuracy is made possible by using special fluids with high polymer concentrations. This gives them a viscoelastic character that can push like water and spring back, comparable to egg white. By combining these forces, particles can be made to move in specific ways.
“We have shown how to increase sample throughput in our microfluidic channel,” he says. “This would reduce the process time for blood analysis, which is critical for a patient.”
The study found that larger particles were easier to control and remained concentrated even as fluid flow increased. Smaller particles required optimal flow rates to stay in line, but showed better control under the right conditions.
The development of the method goes back to a project funded by the European Commission to develop technologies for monitoring micro- and nanoplastics in water. Tanriverdi was involved in the project, called MONPLAS, as a Marie Skłodowska-Curie researcher.
Read the research article in Nature Microsystems & Nanoengineering https://doi.org/10.1038/s41378-024-00724-2
