Organic electrochemical transistors (OECTs) are designed to measure signals created by electrical impulses in the body, such as heartbeats or brainwaves. However, they are currently only able to measure certain signals. Researchers have created a material that measures signals in a way that is different from traditional OECTs that they believe could be used in complementary circuits, paving the way for new biological sensor technologies.
It will also allow new applications, particularly in the sensing of biologically important positive ions, which are not feasible with current devices. For example, these materials might be able to detect abnormalities in sodium and potassium ion concentrations in the brain, responsible for neuron diseases such as epilepsy.
The researchers demonstrated the first ambipolar OECT that can conduct electrons as well as holes with high stability in water-based solutions. The team overcame the seemingly inherent instability of n-type materials in water by designing new structures that prevent electrons from engaging in side-reactions, which would otherwise degrade the device.