Nano-robots fight bacterial sinusitis mechanically

A Chinese research team has developed nano-robots the size of a grain of dust that can work together in a swarm to combat deep-seated bacterial sinusitis. They use mechanical forces to destroy the cell walls of the bacteria. Initial trials have been very promising.

Chronic sinusitis is difficult to treat. In most cases, invasive surgery or antibiotics have to be administered, but these often cease to work overtime. The Chinese research team is taking a different approach and using nanorobots, Copper Single-Atom-Loaded Bismuth Oxoiodide Photocatalytic Microrobots (CBMRs). Using robots to combat bacterial sinusitis is nothing new. Magnetic robots have already been used, but they were barely able to work their way through areas clogged with viscous pus and cell debris. The Chinese researchers' CBMRs, on the other hand, are said to be light- and magnet-controlled and able to effectively push back even deep sinusitis.

The nano-robots consist of tiny magnetic particles containing antibacterial copper, the scientists write in the study “Photocatalytic microrobots for treating bacterial infections deep within sinuses”, which was published in Science Robotics. The robots are controlled using a magnetically controlled glass fiber and simultaneously illuminated with visible light. The robots injected into the sinus cavity via the nasal passage are moved to the site of infection via the magnetic optical fiber. The movements of the CBMRs are coordinated. The robots can move better as they emit heat when activated by the light.

Mechanical control of the bacteria

The nanorobots also exert collective mechanical forces under the magnetic field. This breaks down the cell walls of the bacteria. The robots also generate antibacterial reactive oxygen species (Antibacterial Reactive Oxygen Species – ROS). These free radicals then kill the exposed bacteria.

The scientists tested the robots in the laboratory on rabbit models in which bacterial biofilms with sinusitis had been introduced. In addition, the nanorobots were tested on dead pigs infected with bacterial sinusitis. In both cases, the inflammations were effectively combated. There was no tissue damage or side effects. The nanorobots could be eliminated from the nose naturally after their work.

The non-invasive procedure has clear advantages over conventional treatment methods: Firstly, no physically stressful operations are necessary. Secondly, there is no need for the usual administration of antibiotics, which can often lead to antibiotic resistance.

(olb)