A new wave of personal health and environmental monitoring devices

“It's like a Fitbit, but has a biosensor that can count particles, so that includes blood cells, bacteria and organic or inorganic particles in the air,” said Assistant Professor Mehdi Javanmard of Rutgers University–New Brunswick.

"Current wearables can measure only a handful of physical parameters such as heart rate and exercise activity,” added Abbas Furniturewalla of Rutgers University–New Brunswick. “The ability for a wearable device to monitor the counts of different cells in our bloodstream would take personal health monitoring to the next level.”

The plastic wristband includes a flexible circuit board and a biosensor with a thin channel, or pipe, with gold electrodes embedded inside. It has a circuit to process electrical signals, a micro-controller for digitising data and a Bluetooth module to transmit data wirelessly.

Blood samples are obtained through pinpricks, with the blood fed through the channel and blood cells counted. The data are sent wirelessly to a smartphone with an app that processes and displays data.

In the field, offices and hospitals, health professionals could get rapid blood test results from patients, without the need for expensive, bulky lab-based equipment, say the researchers. Blood cell counts can be used to diagnose illness; low red blood cell counts, for instance, can be indicative of internal bleeding and other conditions.

“There’s a whole range of diseases where blood cell counts are very important,” Assist Prof Javanmard said. "Abnormally high or low white blood cell counts are indicators of certain cancers like leukemia, for example.”

He also pointed to use cases such as measuring dust particle exposure for those working in harsh environments, such as miners.