Wearable sensor to revolutionise heart monitoring?

Developed by Zhenan Bao, a professor of chemical engineering at Stanford University, the ultra thin, postage stamp sized sensor can be worn under an adhesive bandage on the wrist to monitor a patient's pulse. To make the heart monitor both sensitive and small, Bao's team combined layers of organic semiconductors with a thin middle layer of compressible rubber covered with tiny pyramid bumps only a few microns wide. When pressure is put on the device, the pyramids deform slightly, changing the size of the gap between the two halves of the device. This change in separation causes a measurable change in the electromagnetic field and the current flow in the device. The more pressure placed on the monitor, the more the pyramids deform and the larger the change in the electromagnetic field. When the sensor is placed on someone's wrist using an adhesive bandage, the sensor can measure the person's pulse wave as it reverberates through the body. According to Bao, the device is so sensitive that it can even detect more than just the two peaks of a pulse wave, opening up the possibility of it being used for more detailed diagnostics in the future. The team is now working with other researchers to make the device completely wireless. More information is available in the video below.