About 5% of the world’s population has a brain aneurysm, but few of them produce symptoms or consequences. The real problem begins when the artery ruptures, causing a brain hemorrhage. Now, a new study has used rBots smaller than most bacteria to deliver drugs directly to the site of a brain aneurysmpreventing a stroke.
So far, the new technology has only been tested on rabbits, but with further studies, it could become an alternative to stents currently used to stabilize aneurysms in human patients.
This technology would be able to stop bleeding caused by an aneurysmin which the wall of an artery weakens and swells. The results have been published in Small and have been led by Qi Zhou, an expert in bioinspired engineering at the University of Edinburgh.
“Our remote controlled magnetic nanorobots “They provide a more precise and safe way to quickly close brain aneurysms without using implants,” Zhou said in a statement. “They can also alleviate the laborious task of surgeons inserting a long, thin microcatheter through complex networks of blood vessels.”
Aneurysms can form in any artery in the body. When they form in the brain, they can burst and cause a stroke. To come up with a new solution for these dangerous events, Zhou and his colleagues developed nanorobots that They measure only 295 nanometers in diameterFor comparison, a typical virus is about 100 nanometers wide and Most bacteria measure in the range of 1,000 nanometers.
Each tiny robot consists of a magnetic core, a clotting agent called thrombin that treats the aneurysm, and a coating that melts when slightly heated to release the drug. “Using a magnetic field, nanorobots can be guided to the aneurysm – Zhou adds – Concentrated heat is then used to melt the coating, releasing the drug and blocking the aneurysm from blood circulation.”
This heat is applied with an alternating magnetic field, which essentially creates friction by altering the alignment of the particles exposed to the field. The temperature is kept below 50 degrees Celsius so that it does not damage body tissue. The idea is that cardiovascular surgeons can release these nanorobots into the bloodstream, towards the aneurysm, using a microcatheter. This would prevent them from having to go too deep into the fine vessels of the brain.
Zhou’s team first evaluated the nanorobots’ biocompatibility on human cells in lab dishes. A biocompatible material can be introduced into living tissue without causing harm or unwanted side effects. They also conducted preliminary animal studies, treating three rabbits for artificially induced aneurysms in the carotid arteries, which feed the brain and head.
“We found that nanorobots could be successfully guided to the aneurysm in a clinical intervention setting and stabilize a clot and then completely block it,” Zhou said.
During a two-week follow-up period, the three rabbits They remained healthy, with stable clots blocking their aneurysms.These clots do not block the blood supply to the brain, but rather close the weak spot in the vessel so that it does not burst.
Looking ahead, the technology will need to be tested on larger animals that better mimic the human body, the study concludes. The Safety and efficacy of nanorobots in longer-term studiesto see how it affects the brain over time. In the rabbit tests, the aneurysms were located at shallow depths, so the team will also need to improve the magnetic control system to better guide the robots toward aneurysms deep in the brain.