Manufacturers of RNA extraction kits have had difficulty keeping up with demand during the COVID-19 pandemic, hindering testing capacity worldwide.
‘A new COVID-19 testing method directly detects coronavirus RNA in less time.’
To overcome this, A team of researchers using a chelating agent made by the lab supply company Bio-Rad called Chelex 100 resin to preserve coronavirus RNA in samples for detection by RT-qPCR. This finding is reported in the journal iScience.
“We used nasopharyngeal and saliva samples with various virion concentrations to evaluate whether they could be used for direct RNA detection,” said Guan, the lead author.
Researchers made their discovery by testing a variety of chemicals using synthetic and human samples to identify those that could preserve the RNA in samples with minimal degradation while allowing direct detection of the virus by RT-qPCR.
To validate the test, they collected patient samples (on Research Protocol NIH IRB 20-D-0094) and stored them in either viral transport media, or the newly developed chelating-resin-buffer at the NIH Symptomatic Testing Facility.
The samples in viral transport media were tested by the COVID-19 testing team at NIH’s Clinical Center using conventional RNA extraction and RT-qPCR testing.
The samples in the chelating-resin-buffer were heated and the viral RNA was, then, tested by RT-qPCR. The new preparation significantly increased the RNA yield available for testing, compared to the standard method.
This novel methodology has clear benefits of increasing sensitivity, cost and time saving for COVID-19 testing. NEI has protected the intellectual property around this technology and is seeking partners for co-development/licensing.
Source: Medindia