For athletes looking to track their workouts or physicians who want to monitor a patient's heart disease, a flexible Chem-Phys patch from the University of California San Diego analyzes the body's biochemical and electric signals. The Chem-Phys wearable technology records electrocardiogram (EKG) heart signals and detects levels of lactate, a biochemical that is a marker of physical effort, in real time.

The device, worn on the chest, communicates wirelessly with a smartphone, smartwatch, or laptop.

Nanoengineers and electrical engineers at the UC San Diego Center for Wearable Sensors worked together to build the technology, which includes a flexible suite of sensors and a small electronic board. The device also can transmit the signal data via Bluetooth.

"One of the overarching goals of our research is to build a wearable tricorder-like device that can measure simultaneously a whole suite of chemical, physical and electrophysiological signals continuously throughout the day,” said UCSD electrical engineering professor Patrick Mercier. “This research represents an important first step to show this may be possible.”

The researchers used screen printing to manufacture the patch on a thin, flexible polyester sheet that can be applied directly to the skin. The lactate-sensing electrode was printed in the center of the patch, with two EKG electrodes bracketing the sensor to the left and the right.

To avoid interference, the engineers experiemented with the best distance between electrode. The tean found that a distance of four centimeters (roughly 1.5 inches) between the EKG electrodes was optimal.

Next steps include improving the way the patch and the board are connected and adding sensors for other chemical markers, such as magnesium and potassium, as well as other vital signs.