The next big biofuel source could be the most locally sourced yet—it'll come from your own skin.
A research team out of the University of California at San Diego led by Joseph Wang has created a sweat-powered radio that was able to run for two days on perspiration. Researchers used a soft, flexible skin patch just a few centimeters across that contains enzymes that replace the precious metals traditionally used in batteries.
The technology could potentially be used in wearable activity or health trackers, researchers say. The patch produces enough current to power a light-emitting diode or a Bluetooth radio.
Getting enough power from a biofuel cell to make it a viable fuel source has long proved elusive, but this latest innovation can extract 10 times more power than previous versions. "We're now getting really impressive power levels," Wang told New Scientist. "If you were out for a run, you would be able to power a mobile device."
Wang and his colleagues used the lactate found in sweat to power the cells. The amount of lactate or lactic acid found in sweat is also related to how efficiently a person's muscles are functioning.
"The most exciting application is wearable sensors that can monitor health conditions," Mirella Di Lorenzo at the University of Bath in England told New Scientist. "Then sweat could generate enough power for a Bluetooth connection so that the results could be read straight from a smartphone."
Another potential application is glucose monitoring, which would allow diabetics to ditch needles or blood samples, since levels of glucose in sweat are related to its concentration in the blood.
