Medical technology Tiny robots can wander through human tissue

A swarm of robots swims through an eye for the first time

In hardly any other area are the advances in medical technology so reminiscent of science fiction novels and films as in nanotechnology. Recently, a team of researchers reported on special nanorobots that are able to traverse human tissue and freely swim around in an eyeball. The tiny little robots will be used in the future to bring drugs in the body exactly where they are needed.

Researchers at the Max Planck Institute for Intelligent Systems have developed a specially coated nanopropeller capable of maneuvering through dense tissue, such as a glass body in the human eye. Until now, nanoribots could only be controlled by liquids. By overcoming solid tissue nanorobotics reaches a new level in medical technology. The results of the research were recently presented in the journal Science Advances.

Yesterday still fiction, today already a reality. Tiny nanorobots move through the body and even overcome solid tissue. They should be used for medical purposes. (Image: gorbovoi81 / fotolia.com)

Operations without intervention

As the international research team reports, the further development of nanorobots is a major step for medical technology. In the foreseeable future, it will be possible to perform a variety of therapies without major surgery where surgery is still required today. The nanorobots could be used as minimally invasive tools that deploy drugs exactly where they are needed without first having to travel through the gastrointestinal tract or through the bloodstream.

The smallest propeller machine in the world

The propeller-shaped nanorobots are just 500 nanometers wide. This means that they are 200 times smaller than the diameter of a human hair. According to the research team, they are so small that they can slip through the tight mesh of a solid tissue, as is the case in the vitreous body of the eye. "Their helical structure, size and slippery coating enable the nanoprinters to move through one eye relatively unhindered, without damaging the delicate tissue around them," writes the Max Planck research team.

Inspired by nature

Since the consistency inside the eye is particularly sticky and tough, the researchers used a very special two-layer non-stick coating to prevent the robots from getting stuck in the tissue or obstructing each other. "When it came to coating, we were inspired by nature," explains study author Zhiguang Wu in a press release.

What do carnivorous plants and nanorobots have in common??

"We applied a liquid layer to the nanopropellers found in the carnivorous pitcher plant (Nepenthes)," Wu explains. The leaves of the pitcher plant create a kind of pitfall. If insects land on them, they will not stop on the slippery coating and fall inside, where they are digested by a liquid. According to the researchers, the same coating ensures that the nanorobots do not get stuck in the eye. "As slippery as the Teflon coating of a frying pan," comments Wu.

With magnetic drive through the eye

The small robots can be controlled from the outside. They are driven by magnetism. Iron particles built into the propeller, according to the scientists, allow the mini-tracker to be controlled in a magnetic field to the desired destination.

Not only usable in the eye

"The magnetic drive of the nanorods, their small enough size, and the slippery coating are not only eye-catching, but can also be useful for the penetration of other tissues in the human body," adds Tian Qiu, another author of the study. So far, propeller robot movement has only been tested within dissected pig eyes. With a small needle, tens of thousands of helical robots could be injected into the eye. The robots then move together as a swarm. (Vb)