Nanorobot hand made of DNA grabs viruses for diagnostics and blocks cell entry

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A tiny, four-fingered “hand” folded from a single piece of DNA can pick up the virus that causes COVID-19 for highly sensitive rapid detection and can even block viral particles from entering cells to infect them, University of Illinois Urbana-Champaign researchers report. Dubbed the NanoGripper, the nanorobotic hand also could be programmed to interact with other viruses or to recognize cell surface markers for targeted drug delivery, such as for cancer treatment.

Led by Xing Wang, a professor of bioengineering and of chemistry at the U. of I., the researchers describe their advance in the journal Science Robotics.

Inspired by the gripping power of the human hand and bird claws, the researchers designed the NanoGripper with four bendable fingers and a palm, all in one nanostructure folded from a single piece of DNA. Each finger has three joints, like a human finger, and the angle and degree of bending are determined by the design on the DNA scaffold.

“We wanted to make a soft material, nanoscale robot with grabbing functions that never have been seen before, to interact with cells, viruses and other molecules for biomedical applications,” Wang said. “We are using DNA for its structural properties. It is strong, flexible and programmable. Yet even in the DNA origami field, this is novel in terms of the design principle. We fold one long strand of DNA back and forth to make all of the elements, both the static and moving pieces, in one step.”

The fingers contain regions called DNA aptamers that are specially programmed to bind to molecular targets — the spike protein of the virus that causes COVID-19, for this first application — and trigger the fingers to bend to wrap around the target. On the opposite side, where the wrist would be, the NanoGripper can attach to a surface or other larger complex for biomedical applications such as sensing or drug delivery.

To create a sensor to detect the COVID-19 virus, Wang’s team partnered with a group led by Illinois electrical and computer engineering professor Brian Cunningham, who specializes in biosensing. They coupled the NanoGripper with a photonic crystal sensor platform to create a rapid, 30-minute COVID-19 test matching the sensitivity of the gold-standard qPCR molecular tests used by hospitals, which are more accurate than at-home tests but take much longer.

“Our test is … Read More