Engineers can detect ultra rare proteins using a cellphone camera

One of the frontiers of medical diagnostics is the race for more sensitive blood tests. The ability to detect extremely rare proteins could make a life-saving difference for many conditions, such as the early detection of certain cancers or the diagnosis of traumatic brain injury, where the relevant biomarkers only appear in vanishingly small quantities.

cell phone camera capturing an image at the Issadore Lab
The researchers’ detection system uses a standard cellphone camera. (Photo courtesy: Penn Engineering)

Commercial approaches to ultrasensitive protein detection are starting to become available, but they are based on expensive optics and fluid handlers, which make them relatively bulky and expensive and constrain their use to laboratory settings.

Knowing that having this sort of diagnostic system available as a point-of-care device would be critical for many conditions, especially traumatic brain injury, engineers at the University of Pennsylvania have developed a test that uses off-the-shelf components and can detect single proteins with results in a matter of minutes, compared to the traditional workflow, which can take days.

Using a standard cellphone camera and a set of strobing LED lights, combined with their lab’s microfluidic droplet generators, the team has developed a system that is a thousand times more sensitive than the standard protein assay, is handheld, and considerably less expensive than the current state-of-the-art single-protein tests first coming to market.

The researchers, led by David Issadore, assistant professor in Penn Engineering’s Department of Bioengineering, and graduate student Venkata R. Yelleswarapu, demonstrated their system in a study published in the Proceedings of the National Academy of Sciences.

Read more at the Penn Engineering blog