Pulse oximetry (SpO2) has been around for decades, helping clinicians to monitor the oxygenation of patients without resorting to invasive methods. Lately, with the rise of personal fitness trackers, pulse oximetry is being looked upon as a promising new metric for sports enthusiasts to analyze their workouts. The limitation to making this happen practically has been the fact that existing pulse oximeters are rigid, somewhat bulky devices that have to be worn around the finger or kept attached to an earlobe. Now researchers at UC Berkeley have developed a flexible pulse oximeter that can wrap around a finger and provide continuous SpO2 and pulse rate readings.
Instead of relying on boring old silicon, the researchers used organic, carbon-based components layered onto a plastic substrate, so the device was made flexible and quite thin. Unlike conventional pulse oximeters that use red and infrared light, the device relies on red and green organic LEDs (OLEDs) to measure oxygen in the blood below the skin. Additionally, small changes in the blood flow are indicative of the heart beat, allowing the device to also measure the pulse rate. The researchers tested the device in the laboratory, comparing it to commercial pulse oximetry, showing that the device is about as accurate as what you will find on the fingers of your patients recovering in the ICU.
Study in Nature Communications: All-organic optoelectronic sensor for pulse oximetry…
More from Berkeley: Organic electronics could lead to cheap, wearable medical sensors….