They're not just good for playing Fruit Ninja and reminiscing about Flappy Bird - turns out, your smartphone has the potential to be a pocket-sized doctor.
More specifically, the smartphone has the capability to become a real-time diagnostic device, thanks to nanotechnology biosensing that simply requires your phone and a lens attachment, which developers hope will run at around $20. The lens, intended to act in lieu of a microscope, looks for evidence of a chemical reaction as a standard diagnostic tool would, with observing the relationship between telltale pathogens and molecules the key to diagnosis.
Developed by University of Houston scientists Jiming Bao and Richard Willson, the device requires a glass slide covered by a thin layer of gold riddled with minuscule laser-cut nanoholes - measuring just 600 nanometers each - that enable light to pass through. For a little context, the width of a single human hair is 60,000 nanometers. To effective diagnose a patient, a pathogen sample is placed on the slide, with the slide then immersed in a solution of antibodies that react specifically to different pathogens and allow a silver substance to cloud the holes. The slide is rinsed, and a light is then aimed at the holes to check if they're blocked - a process that needs to be viewed under a microscope due to the size of the holes (though the team hopes a smartphone camera flash will soon be able to step into this responsibility). If so, the result of the test is positive, meaning a firm diagnosis.
The development of a diagnostic smartphone was largely built around the idea of quick diagnosis for those in fieldwork, such as industrial-site injuries, though there is also some potential for its usage in remote areas. "There are a lot of situations where an affordable diagnostic tool that is simple to use and simple to interpret could be very useful. If both your disposables and your reader are cheap, that makes it a lot easier to extend your system out into the real world," said Professor Willson.
Indeed, Willson also pointed to the lower price point as instrumental in making the tool accessible to a broader group of people. "Some of the more advanced diagnostic systems need $200,000 worth of instrumentation to read the results," he said, though "with this, you can add $20 to a phone you already have and you're done."
The study, titled Transmissive Nanohole Arrays for Massively-Parallel Optical Biosensing, was published in ACS Photonics.