Reverse transcription-polymerase chain reaction (RT-PCR) has been the gold standard for diagnosis during the COVID-19 pandemic.
However, the PCR portion of the test requires bulky, expensive machines and takes about an hour to complete.
Scientists have now developed a plasmofluidic chip that can perform PCR in about eight minutes, which could speed diagnosis during current and future pandemics.
Currently, RT-PCR is the most sensitive and reliable diagnostic method, but because the PCR portion of the test requires 30–40 cycles of heating and cooling in special machines, it takes about an hour to perform, and samples must typically be sent away to a lab.
The team of scientists devised a postage stamp-sized polydimethylsiloxane chip with a microchamber array for the PCR reactions.
They tested the device on a piece of DNA containing a SARS-CoV-2 gene, accomplishing 40 heating and cooling cycles and fluorescence detection in five minutes, with an additional three minutes for sample loading.
The amplification efficiency was 91%, whereas a comparable conventional PCR process has an efficiency of 98%.
The new device could provide many opportunities for rapid point-of-care diagnostics during a pandemic, the researchers say.
Image credit | Korea Advanced Institute of Science and Technology(KAIST)