University of Illinois Scientists Use Structural DNA to Make Tiny ‘Hand’ That ‘Grabs’ COVID-19 Coronavirus
Study shows clinical laboratories may one day use nanorobotic tests to help prevent spread of viral infections, cancer, and other diseases
Scientists from the University of Illinois Urbana-Champaign (U of I) have developed a tiny robotic “hand” made from structural DNA that “grabs” viruses—including the COVID-19 coronavirus—potentially preventing them from infecting cells. Such a nano-robotic antiviral technology could be used by anatomic pathologists and clinical laboratory managers in the future as a point-of-care type of test.
This is yet another example of out-of-the-box thinking by developers of diagnostic technology. Led by Xing Wang, PhD, professor of bioengineering and of chemistry at the U of I, the scientists dubbed their DNA device the NanoGripper.
Similar to a piece of origami (Japanese art of folded paper), the so-called hand has “four bendable fingers and a palm, all in one nanostructure folded from a single piece of DNA,” according to a U of I news release. The scientists found in their study that the hand was capable of doing a rapid test to identify the (COVID-19) virus and “prevented the viral spike proteins from infecting the cells,” Gizmodo reported.
“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,” said Wang in the news release.
The scientists published their findings in the journal Science Robotics titled, “Bioinspired Designer DNA NanoGripper for Virus Sensing and Potential Inhibition.”
“It would be very difficult to apply it after a person is infected, but there’s a way we could use it as a preventive therapeutic,” said Xing Wang, PhD (above), associate professor, bioengineering and chemistry, University of Illinois Urbana-Champaign, in a news release. “We could make an anti-viral nasal spray compound. The nose is the hot spot for respiratory viruses, like COVID or influenza. A nasal spray with the NanoGripper could prevent inhaled viruses from interacting with the cells in the nose.” Clinical laboratories may one day perform antiviral testing that uses U of I’s NanoGripper technology. (Photo copyright: University of Illinois.)
How a DNA Nanorobot Grabs a Virus
The U of I researchers wanted to leverage what has been discovered about DNA as a “material for constructing versatile nanorobots for biomedical applications,” they wrote in Science Robotics. However, previous studies had not achieved the current origami design of a nanoscale mechanism, the authors added.
With robotic precision and its DNA structure, the researchers’ NanoGripper moves and enables fingers to bend for “customized interactions with target molecules,” Interesting Engineering reported, adding that the technology also:
- Employed DNA aptamers on the fingers which act as “molecular locks” to find and bind to specific targets.
- In a demonstration, wrapped its fingers around the target spike protein of the COVID-19 coronavirus, essentially “disabling its ability to infect cells.”
The NanoGripper binds to the virus with the help of “pattern-recognition-enabled multivalent interaction,” Wang told The Pathologist.
“The aptamers are arranged into a spatial pattern that specifically matches that of the trimeric spike protein on the virus outer surface. Such pattern recognition-enabled multivalent interaction—a principle developed by my group—has induced ultrahigh NanoGripper virus-binding avidity, resulting in enhanced virus diagnosis sensitivity,” Wang said.
Taken from the U of I news release, the image above shows how “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.” Such nano-robotic technology could become a new clinical laboratory test for diagnosing viral infections, or even a preventative treatment if caught prior to infection. (Photo and caption copyright: University of Illinois.)
Developing a Test for COVID-19
The scientists discovered that when equipped with a photonic crystal sensor, NanoGripper detected the SARS-CoV-2 coronavirus in 30 minutes with sensitivity equal to RTqPCR tests, Gizmodo reported.
“The NanoGripper functions as a highly sensitive biosensor that selectively detects intact SARS-CoV-2 virions in human saliva with a limit of detection of 100 copies per milliliter, providing a sensitivity equal to that of reverse transcription quantitative polymerase chain reaction [RTqPCR],” the authors wrote in Science Robotics.
In fact, the NanoGripper test is reportedly faster and easier than RTqPCR testing, which requires sophisticated instruments.
“Our test is very fast and simple since we detect the intact virus directly,” said study collaborator Brian Cunningham, PhD, professor, electrical and computer engineering and bioengineering at U of I, in the news release.
“When the virus is held in the NanoGripper’s hand, a fluorescent molecule is triggered to release light when illuminated by an LED or laser,” he said, adding, “When a large number of fluorescent molecules are concentrated upon a single virus, it becomes bright enough in our detection system to count each virus individually.”
More Research and Applications
Gizmodo compared the NanoGripper to a “true Swiss army knife,” able to change and detect other viruses such as HIV and influenza (Flu).
The U of I researchers have already studied the NanoGripper’s ability to detect hepatitis B and plan to publish findings soon, Wang told The Pathologist. He also noted it’s possible the NanoGripper “can be integrated with a lateral flow assay paper strip platform for development of a rapid, sensitive, and inexpensive at home or point-of-care virus detection.”
There is “power in soft nanorobotics,” said Wang, who envisions potential for the NanoGripper beyond viruses to include programming the fingers to detect cancer markers and enabling the grippers to deliver treatment to target cells.
Clinical pathologists and laboratory managers may want to follow this research coming out of the University of Illinois Urbana-Champaign. Once put through additional clinical studies, such nanorobotic diagnostic technology might eventually be used at the point-of-care to help prevent viral infection and spread of disease.
—Donna Marie Pocius
Related Information:
Nanorobot Hand Made of DNA Grabs Viruses for Diagnostics and Blocks Cell Entry
Scientists Built a Tiny DNA “Hand” That Grabs Viruses to Stop Infections
Bioinspired Designer DNA NanoGripper for Virus Sensing and Potential Inhibition
Tiny Four-Fingered DNA Robot Hand Grabs COVID Virus, Shields Cells from Infection
Folded DNA “Hand” Grips Virus Particles in a Rapid Detection System in Liquid Samples
