Swarms of microrobots to clean sinuses found to be potential risk

Researchers say that scores of tiny robots, each no bigger than a speck of dust, could be deployed to treat stubborn sinus infections before being flushed out through the nose into a tissue. Scientists in China and Hong Kong have succeeded in testing the devices on animals, but potential concerns include the risk of the devices remaining in the body and public suspicion.

Microrobots the thickness of a human hair have been successfully implanted into the sinuses of animals in pre-clinical trials carried out by researchers from universities in China and Hong Kong, The Guardian reports.

Swarms of microrobots are introduced into the nasal cavity through a canal running through the nostril and are guided to their target using electromagnetism, where they can be made to heat up and catalyse chemical reactions to kill bacterial infections. It is hoped that the precisely engineered technology could eventually reduce reliance on antibiotics and other one-size-fits-all drugs.

These tiny devices are part of a growing field of medical applications for micro- and nanorobots, The Guardian notes. They have also been developed to deliver drugs and remove bacteria from medical implants such as stents and hernia mesh.

Experts believe they could find clinical use in five to 10 years to treat bladder, bowel and sinus infections. Scientists in China, Switzerland, the US and the UK are developing more advanced versions that can travel through the bloodstream.

The latest development is the result of collaboration between scientists from the Chinese University of Hong Kong and universities in Guangxi, Shenzhen, Jiangsu, Yangzhou and Macau.

Researchers in this emerging field acknowledge that there are risks associated with some tiny microrobots being left behind after treatment, which could cause long-term side effects.

Another potential problem cited by technology experts is public suspicion at the thought of implanting robots into the human body and conspiracy theories that arise from concerns that robots could be activated without consent.

The latest breakthrough, based on animal rather than human testing, involves using magnetic particles “doped” with copper atoms that doctors insert through a catheter before guiding them to their target using a magnetic field.

The clusters can be heated by reacting to light from an optical fibre, which is also inserted into the body as part of the therapy. This allows the microrobots to loosen and penetrate the sticky pus that forms a barrier to the infection. The light source also prompts the microrobots to break down the cell walls of bacteria and release reactive oxygen species, which kill the bacteria.

A study published in the journal Science Robotics found that robots were able to kill bacteria from the sinuses of pigs and could clear infections in live rabbits “without apparent tissue damage.”

The researchers created a model of how the technology might work in humans: swarms of robots were deployed in an operating room, allowing doctors to see their progress using X-rays. They suggested future applications could include fighting bacterial infections of the respiratory tract, stomach, intestines, bladder and urethra.

“Our proposed microrobotic therapeutic platform has the advantages of non-invasiveness, minimal resistance and no drug intervention,” they said.

Professor Sylvain Martel, director of the nanotechnology lab at the Polytechnic Institute of Montreal in Canada, who was not involved in the study, said the science appears to be working.

"It's like a rocket that can be guided by a magnetic field," he said.

He predicts that microrobots could be available for treatment in three to five years, but perhaps not for another decade, as regulators still need to approve their use and manufacturing processes, which differ from those used in standard pharmaceuticals.

“The main advantage of microrobots is targeting,” Martel says. “Instead of taking drugs that enter the bloodstream and go to the right place in small amounts, you can administer them specifically.”

The professor hopes the public will soon be free of any fears about the idea of ​​implanting robotic devices in their bodies. “They may be scared at first,” he said. “But they will get used to it pretty quickly.”

Dr Andrea Soltoggio, an AI expert at Loughborough University, said: “The public may be suspicious of non-biological entities such as nanorobots being implanted in our bodies. This may even give rise to conspiracy theories. But it is important to look at what nanorobots are intended to do. What we are seeing here is an example of targeted intervention, aimed at reducing or eradicating infection through localised action. Nanorobots often have simpler and more targeted behaviour than many drugs, and could effectively complement a wide range of treatments.”