Scientists Achieve Autonomous Control of Microscopic Machines

Tohoku and Kyoto University researchers have successfully created a DNA-based molecular controller that autonomously controls molecular robot building and disassembly. This innovative technology represents a major advancement toward sophisticated autonomous molecular systems that may find use in nanotechnology and medicine.

Our newly developed molecular controller, composed of artificially designed DNA molecules and enzymes, coexists with molecular robots and controls them by outputting specific DNA molecules. This allows the molecular robots to self-assemble and disassemble automatically, without the need for external manipulation.”

Shin-ichiro M. Nomura, Associate Professor and Study Co-Author, Graduate School of Engineering, Tohoku University

The ability of molecular robots to operate autonomously is an important development since it allows them to carry out activities in areas that are inaccessible to outside signals.

The research co-authors include Ibuki Kawamata (Associate Professor at Kyoto University's Graduate School of Science), Kohei Nishiyama (Graduate Student at Johannes Gutenberg University Mainz), and Akira Kakugo (Professor at Kyoto University's Graduate School of Science).

The study of molecular robots, which can operate both within and outside the body and are intended to help in illness diagnosis and therapy, is becoming increasingly popular. In earlier work, Kakugo and associates created molecular robots that move independently like a swarm.

External manipulation could be used to assemble and disassemble these robots collectively. However, the robots are able to self-assemble and disassemble in accordance with a preprogrammed sequence because of the built molecular controller.

The molecular controller outputs a specific DNA signal equivalent to the instruction “assemble” to start the process. The same solution's DNA-modified microtubules, driven by kinesin molecular motors, recognize the DNA signal, align their direction of motion, and automatically come together to form a bundled structure.

The microtubule bundles then automatically deconstruct as the controller sends out a “disassemble” signal. The molecular circuit's exact control made this dynamic shift possible, which works similarly to a very advanced signal processor. In addition, the molecular controller and molecular robots live together, removing the need for outside intervention.

It is anticipated that developing this technology will aid in creating increasingly sophisticated autonomous molecular systems; because of this, molecular robots that assemble in response to commands and then disperse to explore targets may be able to carry out activities that humans cannot complete on their own.

Additionally, by combining several molecular groups, such as the motor protein operating system and the DNA circuit system, this research increased the activity conditions of molecular robots.

By developing the molecular controller and combining it with increasingly sophisticated and precise DNA circuits, molecular information amplification devices, and biomolecular design technologies, we expect swarm molecular robots to process a more diverse range of biomolecular information automatically. This advancement may lead to the realization of innovative technologies in nanotechnology and the medical field, such as nanomachines for in-situ molecular recognition and diagnosis or smart drug delivery systems.”

Shin-ichiro M. Nomura, Associate Professor and Study Co-Author, Graduate School of Engineering, Tohoku University