Detecting coronavirus with paper
Credit: Purdue University photo/Rebecca McElhoe
By Shardell Joseph
Engineers have developed a handheld paper divide able to detect a strain of coronavirus quickly and accurately. The strain, MERS-CoV, can be detected by the device in very small quantities, and can be read directly from the device making it portable.
As one of the select few given permission by USA health officials to use diagnostics tests for COVID-19, the Purdue University biomedical engineers claimed that this device could be used to detect the COVID-29 strain – the limitations in doing so currently is the lack of funding. According to the team, the process to scale the technology for manufacturing would cost at least a couple of million US dollars.
‘Paper-based devices are already manufactured – pregnancy tests are paper-based,’ said Purdue University Biomedical Engineering Professor, Jacqueline Linnes.
‘Because this device has a more complex shape, a process hasn’t been developed to make it available on a commercial scale. However, many processes in electronics and paper manufacturing could be translated to scaling up this device.’
But so far, Linnes’ team has just been able to produce these devices on a lab scale, which calls for cutting out the paper components by hand.
‘The most difficult aspect of producing this device is definitely the assembly,’ said Purdue University Biomedical Engineering PhD Cadidate, K Byers.
This time-lapse video shows how a paper device developed by Purdue researchers tests a sample in 40 minutes. This sample is positive for MERS-CoV, as indicated by the formation of a second line on the paper strip. Credit: Purdue University video/K Byers
These challenges may easily be overcome with existing manufacturing techniques, the researchers said.
The device format would not need to change in order to detect other diseases. As the device scales up, however, it would also need to be more sensitive to detect a lower concentration of a virus for clinical relevance.
‘This paper device isn’t dependent on a particular virus or sequence. To detect COVID-19, we would just need an assay design specific to that sequence, which could come from a nasal or throat swap sample. Just like with MERS-CoV, a user could load the assay with liquid into the paper platform, fold the device and let it run,’ Linnes said.
When the device folds over, a liquid wash and chemical substances called reagents push the assay up a paper strip to make an easily visible detection line. This automatically completes a multistep process needed for detecting a virus. A user can check the strip within 40 minutes to see if the sample tested positive.
Read the full paper at: https://pubs.acs.org/doi/full/10.1021/acsomega.0c00115?_ga=2.52130409.1579527955.1583773474-378642389.1583773474
