Maintaining a steady blood oxygen level is critical for the body to stave off breathing problems and organ trouble. For those needing to keep a close eye on things, there's no shortage of monitoring systems and dedicated pulse oximeters available, but these can be somewhat unwieldy. Scientists at the University of California (UC) Berkeley are looking to make the process a little less cumbersome with the development of a thin, blood-oxygen sensor that can be worn much like a Band-Aid.

Typical pulse oximeters rely on LEDs that shoot both infrared and red light through certain parts of the body, usually a fingertip or earlobe, with a sensor waiting on the receiving end to gauge how much makes it through. As blood that is rich in oxygen absorbs more infrared light, and darker low-oxygen blood absorbs more red light, the sensor assesses the ratio of the two as they come out the other side and gains an indication of the blood's oxygen levels.

The UC Berkeley team instead used red and green light, which they say are comparably effective in determining oxygen levels in the blood. These green and red LEDs are made from organic materials and were integrated onto a flexible piece of plastic. The researchers tested the prototype alongside conventional pulse oximeters and discovered the readings to be equally accurate.

“We showed that if you take measurements with different wavelengths, it works, and if you use unconventional semiconductors, it works,” says Ana Arias, associate professor of electrical engineering and computer sciences and head of the UC Berkeley. “Because organic electronics are flexible, they can easily conform to the body.”

One other advantage of the newly developed sensors is that they are much cheaper to manufacture than the conventional versions. Rather than needing to disinfect them for repeated use, the researchers say that the organic sensors could be cheap enough to warrant one-time use before disposal.

The research findings were published in the journal Nature Communications.

Source: UC Berkeley