Targeted drug delivery has recently become increasingly popular among researchers from around the world. But, despite the large number of advantages, this technology also has a lot of disadvantages. The elements used in their construction are currently working on the technology of a chemical gradient. A way out of this situation can serve as a recently created kind of "motors, steering wheel and brakes", which are capable of incredibly accurately delivering the active substance.
Scientists from the University of Redbound in the Netherlands have found a way to completely control the movement of nanocapsules, which allows them to stop when they reach an area with diseased tissue, the temperature of which is always slightly higher than that of normal healthy tissue. In addition, the design also contains elements for controlling the movement and rotation of the capsule. The braking system is a heat-sensitive polymer molecules placed on the body. Changes in temperature cause these molecules to shrink or bend, blocking the access of fuel (in this case, hydrogen peroxide) to the area of the surface covered by the catalyst bed. The sensitivity of these molecules is quite high, and they completely shut off the "supply" of fuel at temperatures of 35 degrees Celsius and above, which makes this miniature nanomechanism stop.
To operate a kind of engine, scientists used an organic catalyst that breaks down hydrogen peroxide into water and oxygen. An external magnetic field acts as the "helm" for the capsules, and the actuating element of this mechanism is a nickel particle grown during the self-assembly of the nano-rocket body. According to the creators,
“We are going to do an even more interesting thing in the future. We plan to replace the "brakes" that respond to temperature changes with brakes that respond to light. This will allow us to regulate the speed or completely stop the movement by illuminating the desired place with laser light. In addition, we plan to make nano-rocket bodies from completely biodegradable materials that will disappear without leaving the slightest trace in the human body."
VLADIMIR KUZNETSOV