Scientists from the University of Oregon have succeeded in modernizing the well-known method of fighting cancer, based on the destruction of cells using local heating. For this, metal particles are injected into the tumor, which begin to heat up up to 38 ℃ in an alternating magnetic field. They transfer heat to the surrounding cells, which leads to their death. But what if the tumor is out of reach for direct and precise injections?
The researchers faced three challenges. First, it is necessary to form a sufficiently powerful heating element inside the tumor for constant exposure. Secondly, there are serious restrictions on the amount of safe doses for single injections. Third, it is necessary to figure out how to concentrate the particles around the target so that the heat is not wasted away.
The solution was to create clusters of iron nanoparticles doped with cobalt and manganese. They have a hexagonal shape and easily form one-piece volumetric structures. Doping increased heat production, and packaging the doses in biodegradable containers allows them to travel safely through the body's vessels to the tumor using a "passive targeting" mechanism.
In experiments on mice with ovarian tumors, nanoparticles were injected directly into the abdominal cavity, moved with the bloodstream, and accumulated around cancer cells. As the concentration of nanoparticles increased, so did the temperature when a safe magnetic field was activated, eventually reaching a value of 44 ℃. Scientists managed not only to remotely destroy cancer cells, but also to master the method of controlling the process by changing the injection schedule. A new form of therapy will soon be tested in humans.