Novel at-home saliva-based Covid-19 test as effective as PCR diagnosis


PTI, Aug 10, 2022, 10:02 AM IST

AP photo

Researchers have developed an at-home, saliva-based testing platform for Covid-19 that is as effective as a PCR test, and can provide results in just 45 minutes.

PCR tests are considered the gold standard in detecting the presence of SARS-CoV-2, the virus that causes Covid-19.

However, these tests can take a few days to process, resulting in unnecessary quarantine for negative individuals or delays for those who require proof of negative testing for travel or other commitments.

Rapid antigen-detecting tests, on the other hand, are convenient, but less reliable than PCR tests, according to the researchers.

To bridge the gap between accuracy and convenience, researchers at the Pennsylvania State University (Penn State) in the US developed the test which can detect the virus with the same level of sensitivity as PCR tests.

“PCR test results take about an hour to develop in a lab, but you have to factor in the time it takes to send the sample to a lab and for the lab to process it,” said Weihua Guan, an associate professor at Penn State.

“We wanted to create a viable alternative to the PCR for people to use at home, without having to endure the invasive nasal test,” said Guan, principal investigator of the study published in the journal ACS Sensors.

The researchers developed a palm-sized testing kit, where an individual spits into a cartridge and inserts it into processing platform. Within 45 minutes, test results are sent to a custom android app developed by the researchers.

The platform uses a technology called reverse transcription loop-mediated isothermal amplification, or RT-LAMP, to detect the virus.

In this technology, the testing device first heats the saliva to 95 degrees Celsius, the temperature at which viral particle shells break apart and release their genetic material.

The genetic material is then mixed with pre-packaged reagents in a microfluidic cartridge.

The sample is cooled to 65 degrees Celsius, triggering another chemical reaction in which a few viral molecules are multiplied into billions of copies, making the virus easier to identify.

If the virus is present in the saliva sample, the user will receive a positive result on their connected smartphone app.

The researchers tested the set up by infusing human saliva samples purchased commercially with inactivated SARS-CoV-2 virus particles and ran the samples through the prototype.

They also tested a few clinical specimens. The platform accurately determined whether every sample was positive or negative for the virus.

“We tested hundreds of mock samples and controlled the quantity of Covid particles in each one,” Guan said.

“Our platform proved to be highly sensitive to the presence of the virus in both the mock and clinical samples, with the standards set by the PCR test as our benchmark,” the scientist added.

Udayavani is now on Telegram. Click here to join our channel and stay updated with the latest news.

Top News

Actress Kasthuri released from jail, says ‘I thank those who made me raging storm’

Kidnapped for ransom in 1998, 26/11 survivor Gautam Adani faces biggest trial

100 engineering colleges in Karnataka to be ‘adopted’ by corporates by next year: IT Minister Kharge

Siddaramaiah defends BPL ration card cancellation, says only ineligible beneficiaries affected

China announces new policy measures to protect its exports from Trump’s new tariff threat

Renovated Medical Oncology OPD and Chemotherapy Day Care Centre inaugurated at Kasturba Hospital, Manipal

Karnataka Health Minister justifies revision of user fees in state-run hospitals

Related Articles More

World COPD Day: Know your lung function

As Delhi chokes with dangerous pollution levels, doctors warn of health risks for all

World Diabetes Day 2024: Kasturba Hospital Manipal Hosts Zumba Session at Malpe Beach to Raise Diabetes Awareness

World Diabetes Day: An overview of types of diabetes

World Diabetes Day: One-fourth of people living with diabetes in 2022 are in India, Lancet study estimates

MUST WATCH

Christmas Cake Fruit Mixing

DK Shivakumar

Rose Cultivation

Geethotsava

Naxal Operation


Latest Additions

Siddaramaiah says confident of winning all three bypolls in Karnataka

Hop on! IT Minister Priyank Kharge checks out Uber Shuttle at Bengaluru Tech Summit

Actress Kasthuri released from jail, says ‘I thank those who made me raging storm’

Kidnapped for ransom in 1998, 26/11 survivor Gautam Adani faces biggest trial

AIMPLB to hold its annual general sessions in Bengaluru from November 23

Thanks for visiting Udayavani

You seem to have an Ad Blocker on.
To continue reading, please turn it off or whitelist Udayavani.