Thursday - May 9 2024, 03:37 UTC - 6 months ago

Researchers have developed microrobots using magnetic beads and a positively charged polymer that can remove both microplastics and bacteria from water. These tiny robots have shown effectiveness in lab experiments and could potentially improve water quality and address the threat of disease spread in aquatic environments.

Plastic pollution has become a global environmental crisis, with discarded plastic waste ending up in our oceans and waterways. As these plastics break down into smaller pieces, known as microplastics, they become increasingly difficult to clean up. Additionally, these tiny particles can pose a threat to both aquatic life and human health. In a recent study published in ACS Nano, researchers have developed a potential solution to this problem - microscopic robots that can remove both microplastics and bacteria from water.

The team, led by Martin Pumera, created these tiny robots using magnetic beads and a positively charged polymer. The polymer strands, which radiate from the surface of the beads, are effective in capturing both microplastics and microbes. With a diameter of only 2.8 micrometers, the individual robots are barely visible to the naked eye.

To control the movement of the robots, the research team exposed them to a rotating magnetic field. The robots self-organize into flat clusters, allowing for precise control over their movements and speed. In lab experiments, the researchers were able to replicate the environment of microplastics and bacteria in water by adding fluorescent polystyrene beads and actively swimming Pseudomonas aeruginosa bacteria to a water tank.

Using a concentration of 7.5 milligrams per milliliter, the densest of four concentrations tested, the microrobots were able to capture approximately 80% of the bacteria in just 30 minutes. The rotating magnetic field was turned on and off every 10 seconds, allowing for the captured bacteria to be detached from the microrobots using ultrasound and exposed to ultraviolet radiation for disinfection. Even after being decontaminated, the microrobots were still able to effectively remove both microplastics and bacteria from water.

This groundbreaking research has the potential to significantly improve water quality in aquatic environments. By harnessing the power of microrobots, researchers can not only remove microplastics but also address the threat of disease spread through water. These tiny robots have demonstrated their potential for improving water quality and addressing the dual threat of pollution and disease in our oceans and waterways.