Medical Breakthrough: Scientists Use Microrobots To Eradicate Bacteria

Micromotors — and their smaller counterparts, nanomotors — are synthetic objects that are self-propelled by energy from their environment. The motion is made possible by asymmetrically structured microjet engines.

These micromotors are being altered to create Low cost method to deal with biofilms, a new study suggested.

Biofilms are a colony of algae,bacterias and protozoans, which Produces a quick sticking glue like substances which makes them resistant to disinfectant and antibiotics.

According to Professor Martin Pumera, a principal investigator for the study “These have profound negative impact, as they cause about 100 billion USD annual loss just in USA” with these biofilms frequently found on medical implants, teeth, catheters, and other surfaces, increasing the risk of infection or failure of the implant. They also have been found to corrode water pipelines and contaminate the water — affecting taste, odor, color, and safety, making the micromotors all the more valuable.

Very few studies have considered using micromotors due to the expensive short lifespan and cost of these micromotors.

However, Pumera and colleagues have successfully synthesized micromotors made of zinc oxide doped with silver (ZnO:Ag) — both of which have antibacterial properties — at a relatively low-cost and environmentally friendly method. The micromotors were stable, round-shaped stars (a rough ball covered with protruding microrods) that self-propel under UV light.

In laboratory tests, these micromotors have been found to be very effective as they have killed more than 80% of the tested biofilms within 5 minutes. In fact, the bacteria Pseudomonas aeruginosa, often found in wounds and drinking water pipes, was killed with a very small amount of motors (1 μg mL−1) in a short time. In addition to causing cell death, the motors caused damage that hindered the formation of new biofilm.

These results have created a great window of opportunities for the broad application of micromotors in biofilm removal in healthcare, industry, and environmental fields.

“We are now focusing on medical application of micro and nanorobotics in removal biofilms in medicine,” said Pumera. “We are also working on collective behavior of these motors, so they can act together and in coordinated action attack the bacteria.”

Reference: M. Ussia, et al., Active Light‐Powered Antibiofilm ZnO Micromotors with Chemically Programmable Properties, Advanced Functional Materials (2021). DOI: 10.1002/adfm.202101178