Detecting subtle proteins in blood can save many lives but they are difficult and lavish to do so. Keeping in line a new study, that can detect them simply with the help of a cellphone camera.
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.
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.
Issadore’s approach works by measuring one protein at a time, by breaking apart the sample into microdroplets, each of which contain either a single protein or none at all.
His lab’s expertise in microfluidics has produced microchips etched with hundreds of microdroplet generators, all working in parallel.
While an off-the-shelf camera can detect whether a microdroplet contains a fluorescent-marker-bound protein or not, the big challenge was to speed up the process.
Rather than having a single channel, the researchers flow droplets into hundreds of channels that pass by the camera at the same time and can capture the data fast.
A cellphone camera takes about a hundred images a second, and that’s far too slow to be useful for us to resolve these droplets.
The trick that makes the Issadore team’s approach work was to encode this strobing light with a signal that would allow them to tease apart one microdroplet from its neighbors.