Researchers at Rice University have a new, laser-powered way to diagnose malaria infection. They say it’s the first through-the-skin method that doesn’t require blood samples or chemical tests. Essentially, it listens for belly sounds as the malaria parasite chows down on blood cells. If it pans out, it could revolutionize how we diagnose this disease.
When the malaria parasite digests red blood cells, it produces hemozoin, a substance that isn’t found in the blood stream of non-infected patients. The research team developed a laser that heats the hemozoin crystals without affecting other components in the blood. The heated hemozoin makes tiny nanobubbles, and the device listens for the unique sound of the bubbles popping — which only lasts ten millionths of a second.
Currently, diagnosing malaria in the countries where it runs rampant is exceedingly difficult, requiring sterile technique to draw a blood sample, the proper chemicals for the test, and a microscope to read the results. The standard test takes 15 minutes, costs $1 each, and it’s ruined in hot climates if it’s not stored properly. By comparison, the laser method is rugged, takes 20 seconds per patient, and can be powered by a car battery, making it feasible for use in the field.
Even better: according to research published in Proceedings of the National Academy of Sciences, the test was able to detect malaria in mice when only one red blood cell in a million was infected, without false positives. The team plans to begin human testing in early 2014.
Image: E. Lukianova-Hleb/Rice University