Test can be run using very small blood sample
by Greg von Portz and Satish Misra, MD
December 14, 2016
British researchers at Imperial College London and hardware developers DNA Electronics have created a way to test for HIV using a USB stick plugged into a computer that analyzes a drop of blood.
Describing what they developed as a “USB stick” is a bit facetious. As described by the research team behind the device, it is a “complementary metal-oxide semiconductor (CMOS) chip-based, pH-mediated, point-of-care HIV-1 viral load monitoring assay that simultaneously amplifies and detects HIV-1 RNA.” That chip is built onto a USB stick, allowing the device to be powered by a connected computer that can also capture data from the device.
Using a small blood sample, this device tests for the presence of HIV RNA, specifically HIV-1. Current tests use complex, costly, and cumbersome machines that take 3 days to produce results. In some remote parts of the world where HIV is prevalent, like sub-Saharan Africa, these tests don’t exist at all. The new device, on the other hand, takes around 30 minutes and is completely portable and disposable, making it easy to run these tests anywhere.
This USB stick could be plugged in to any device that has a USB port, including low-cost tablets or smartphones. And according to the researchers, the overall design of the device could be scaled up in a low-cost way. Having an accurate, fast test that doesn’t break the bank and can go to the patients who need it could affect the long-term care of millions of people.
In this study, the researchers tested the device on 991 plasma samples. When built into the USB stick, which is the use case we were most interested in, the sensitivity was 88% and specificity 95%. While that falls far short of what would be necessary in a mass screening program, this was a proof-of-concept with a version 2.0 in the wings.
In a press release, Chris Toumazou, DNAe’s founder and executive chairman and also a professor at Imperial, stated, “This is a great example of how this new analysis technology has the potential to transform how patients with HIV are treated by providing a fast, accurate, and portable solution. At DNAe we are already applying this highly adaptable technology to address significant global threats to health, where treatment is time-critical and needs to be right first time.”
The HIV testing device is still just a prototype, but the company wants to expand to test for other diseases like hepatitis.
This post appeared on iMedicalApps.com.