A team of micro-robot researchers has developed a groundbreaking system capable of simultaneously removing microplastics and bacteria from water. These microscopic elements, working in harmony like schools of fish, have the potential to address a major environmental concern.
Microplastics, measuring up to 5 mm in size, pose a significant threat to aquatic ecosystems as they can be ingested by animals and enter the food chain, eventually reaching humans. Compounding the issue is the fact that bacteria can colonize these particles, including pathogenic strains, further exacerbating pollution levels.
The researchers designed micro-robots by connecting positively charged polymer chains with magnetic microparticles. These innovative robots have the ability to attract both plastic particles and microbes, offering a dual solution to water contamination.
During laboratory testing, the scientists used luminous polystyrene balls to simulate microplastics and Pseudomonas aeruginosa bacteria, a common pathogen. The micro-robots, placed in a water tank, were subjected to a rotating magnetic field, resulting in the removal of approximately 80% of the bacteria when the robot concentration was 7.5 mg/ml.
Following the water purification process, the micro-robots were retrieved using a permanent magnet, and the bacteria were subsequently separated from them through ultrasound treatment and ultraviolet irradiation for disinfection. Reuse of the disinfected robots demonstrated that they remained effective in collecting microplastics and microbes, albeit in reduced quantities.
This innovative technology of micro-robots presents new possibilities for combating water pollution caused by microplastics and bacterial contamination. The system offers a promising approach to cleaning up water bodies and safeguarding ecosystems from these harmful pollutants.