New Nanorobots Developed That Can Collect and Transport Bacteria in the Microscopic World

Researchers at Julius-Maximilians-Universität Würzburg (JMU), led by Professor Bert Hecht, have created tiny nanorobots capable of directly handling objects within the microbial world. These machines are approximately 50 times smaller than a human hair, allowing scientists new means to manipulate biological materials in water, such as individual cells and bacteria. This innovation addresses the significant challenge of controlling and moving objects at such a small scale.

The design of the nanorobots incorporates up to four plasmonic nanoantennas which enable propulsion through the recoil generated by individual photons. These antennas absorb and emit light in specific directions, resulting in a recoil force akin to that of a bullet being fired. The lightweight nature of the microdrones means these minimal forces can create substantial acceleration and speed.

In their latest developments, the researchers successfully miniaturized the light-powered robots to sizes less than one micrometer. They achieved this by simplifying the steering mechanism while maintaining the photon recoil-based propulsion method. The new control system utilizes nanoscale antenna wires embedded in the robots, which align with the polarization of incoming light, allowing for directional control of the nanorobots while they move forward.

Functionality as “Microscopic Cleaners”

According to Jin Qin, lead experimental scientist on the project, “In essence, we have built a light-driven nanorobot that can track down and collect bacteria.” The simplified design allows these robots to operate efficiently in the microbial world, operating similarly to microscopic cleaning devices. They possess high maneuverability, capable of making swift 90° turns to scan large areas methodically.

Under laboratory conditions, the nanorobots can effectively “clean” microscopic environments, gathering bacteria from one area and depositing them elsewhere with precision. “This is a striking example of how light can be used not only to observe the microscopic world but also to actively shape it,” states Hecht. The robots maintain maneuverability even when transporting larger clusters of bacteria, although their speed diminishes under increased load. This capability suggests potential applications in microbiology, biomedical research, and the intricate manipulation of materials at a microscopic scale.