Are you in danger of having a heart attack? Scientists from Taiwan's National Tsing Hua University and National Cheng Kung University are developing an inexpensive medical biosensor that could let you know, so you can take preventative measures before it's too late.

The portable device, which currently exists as a functioning prototype, is based around what's known as a GaN (gallium nitride)-based high electron mobility transistor, or HEMT. Analyzing just a single drop of blood from a finger prick, within five minutes it can measure concentrations of C-reactive protein (CRP) in the bloodstream.

Elevated CRP levels indicate inflammation that can be linked to imminent heart attack or stroke, or ongoing coronary artery disease.

Biosensors often incorporate more traditional silicon-based field-effect transistors, or FETs, although the high salt concentration in blood samples can affect their accuracy and performance. Gallium nitride doesn't have that problem, and while it is more expensive than silicon, the HEMT used in the new biosensor is very small, so it should hopefully still be quite affordable once it's mass-produced.

Additionally, if different chemical receptors are used in the device, it could conceivably test the blood for other biomarkers besides CRP, and thus warn of other conditions.

"This device will eventually be made as a small handheld device, which can easily connect with a smartphone through Bluetooth or Wi-Fi," says National Tsing Hua University's Prof. Yu-Lin Wang, coauthor of the study. "The data can be collected in an app and users can send that data to their doctors. The operation is just as simple as the blood sugar meter, where anyone can do the test with one drop of blood anywhere, anytime."

Wang believes that a commercial version of the biosensor may be ready to go within one year.

A paper on the research was recently published in the ECS Journal of Solid State Science and Technology.