Author: EIS Release Date: Mar 9, 2020
Researchers from Purdue University’s biomedical engineering school have developed a handheld paper device that quickly and accurately detects coronavirus MERS-CoV and could be used to detect COVID-19.
Developing a process to manufacture it would cost at least a couple of million dollars.
“Paper-based devices are already manufactured – pregnancy tests are paper-based. 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,” says Purdue’s Jacqueline Linnes who specialises in building portable diagnostic tools that can rapidly detect a range of infectious diseases.
Her lab’s devices are made out of cheap but robust paper-like materials, such as glass fiber and cellulose, that have been demonstrated to detect HIV and cholera.
To know if a sample is positive, a user just looks for a second line to appear next to a control line on the device’s paper strip – similar to reading a pregnancy test.
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.
A paper device could be produced using the same roll-to-roll manufacturing tools that make pregnancy tests and a “pick-n-place” process, which is already used to build electronics.
The device format wouldn’t 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.
Folding the device automatically completes a multistep process needed for detecting a virus. 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.
A user can check the strip within 40 minutes to see if the sample tested positive.
Because the reagents are already dried onto the device, a hospital worker who might need to test someone outside of a facility wouldn’t have to carry around reagent vials. The worker would simply need a couple of test tubes to prepare the assay.
A patent application has been filed for this technology, 2017-LINN-67688, through the Purdue Research Foundation Office of Technology Commercialization. The technology is available for license.