Scientists from the University of Utah in the U.S. developed a sensor that could be paired with a smartphone and can detect coronavirus.
Massood Tabib-Azar, a professor at the University of Utah, electrical and computer engineering, has received a $200,000 National Science Foundation Rapid Response Research (RAPID) grant to develop a portable and reusable coronavirus sensor.
The quarter-sized sensor could be paired with the cellphone and give the results within 60 seconds whereas a standard test involves a 6-inch swab inserted through the nose to the back of the cavity for about 15 seconds to get a lab sample and takes about hours to several days to receive the test’s results.
Process of detection of Covid-19 using sensor
First, the user would plug the sensor into the cellphone’s power jack and launch the respective app made for the device. Then, a drop of saliva is placed on the sensor and the result would appear on the screen.
It can also test if the virus is present on a surface by brushing a swab on the surface and then placing it on the sensor. It might be able to detect the presence of floating particles of the virus in the air and in enclosed spaces such as an elevator (this virus is not airborne and non of the studies proves otherwise).
The sensor would use single-stranded DNA called aptamers that are specific and would only bind with the proteins of the novel coronavirus (SARS-CoV-2).
After that, an electrical resistance would be generated which will be measured in the device, signaling a positive result. The entire process would use little battery power from the cellphone.
What are Aptamers?
Aptamers are single-stranded oligonucleotides (DNA or RNA molecules) of about 20-100 nucleotides in length with defined structures that can specifically bind to a target molecule such as proteins via three-dimensional structures. DNA Aptamers are of 15 – 60 oligonucleotide bases long.
SELEX (systematic evolution of ligands by exponential enrichment) is a gold-standard methodology for generating aptamers.
The first aptamer approved for a therapeutic application was Pegaptanib sodium (Macugen; Pfizer/Eyetech), which was approved in 2004 by the US Food and Drug Administration for macular degeneration(deterioration of the central portion of the retina, known as the macula) .
The sensor would include an array of tiny devices inside it, each with an aptamer specific to the virus.
“By increasing the number of devices and single-strand DNA, we can increase the sensor’s accuracy and reduce the false positives and false negatives,”-says Tabib-Azar
It is designed to be reusable as it can destroy the previous sample on it by producing a small electrical current that could produce heat and remove or disintegrate the virus.
“It can be made to be a standalone device, but it can also be connected to a cellphone,”-says Tabib-Azar. “Once you have it connected either wirelessly or directly, you can use the cellphone software and processor to give a warning if you have the virus.”
Another strategy would involve placing saliva on disposable sheets and would be placed on the top of the sensor like a sticky note. This would decrease the chances of cross-contamination on the sensor. There would be no need to heat it up to destroy the virus afterward.
This device could also be designed to map out positive results in an area by uploading the data to a designated database, giving researchers a clear view of the hotspots of the spread of the disease.
This prototype has been originally developed over a year ago for NSF(National Science Foundation) by Tabib-Azar to detect the Zika virus, and will now be converted to develop a new prototype of COVID-19 sensor for clinical trials in two to three months.