Researchers at INSERM (Institut national de la santé et de la recherche médicale) in France, and collaborators, have developed a DNA-based nanorobot called the Nano-winch. The tiny creation is made using DNA molecules and a “DNA Origami” approach. The tiny robot is so small that it can land on a cell surface and interact with ‘mechanoreceptors’ that the cell uses to sense mechanical forces acting on it. 

The robots can apply tiny forces to the mechanoreceptors, allowing the researchers to measure the biochemical and molecular changes that result. While the technology is certainly useful for basic cellular research, it may also pave the way for similar nanorobots with medical applications, given its ability to interact with specific cellular receptors.       

It seems that every week someone develops a new nano- or microrobot that can perform tasks hitherto considered within the realm of science fiction. These breakthroughs could well herald a new era in medicine, with swarms of tiny machines performing an array of complex medical procedures within the body. This latest technology follows this trend, with the ability to land on the cell surface and delicately apply a tiny force to specific cellular receptors.  

The researchers describe their creation as a “programmable DNA origami-based molecular actuator” and have called it the Nano-winch. It consists of three DNA origami structures and can land on the cell surface and apply a force of 1 piconewton to a cellular receptor. To put this in perspective, this is 1 trillionth of a Newton, and 1 Newton is approximately the force exerted by your finger when you click the top of a pen.

The robots can activate several mechanoreceptors at once and incorporate elements that recognize and bind to the receptors to ensure targeting specificity. Such specificity could be very useful in activating other receptors to achieve therapeutic effects, if the technology progresses into the medical arena in the future.

The next step for the researchers is to shield the nanorobots from the enzymatic ravages that they experience within the body, so that they can remain functional for as long as possible. “The design of a robot enabling the in vitro and in vivo application of piconewton forces meets a growing demand in the scientific community and represents a major technological advance,” said Gaëtan Bellot, one of the designers of the new devices. “However, the biocompatibility of the robot can be considered both an advantage for in vivo applications but may also represent a weakness with sensitivity to enzymes that can degrade DNA.”

“So our next step will be to study how we can modify the surface of the robot so that it is less sensitive to the action of enzymes. We will also try to find other modes of activation of our robot using, for example, a magnetic field,” said Bellot.