Organic electrochemical transistor material Measures Electrical Impulses in the Body

New sensor material could enable more sensitive readings of biological signals


Brain signals and other electronic impulses in the body can be identified and measured by organic electrochemical transistors (OECTs), but a material developed to be more sensitive to those impulses has been created.

The material measures signals more effectively and in a different way from traditional OECTs, which are designed to measure signals created by electrical impulses in the body such as heartbeats or brainwaves. Used in complementary circuits, it could pave the way for new biological sensor technologies enabling applications such as in the sensing of biologically important positive ions said researchers.

Semiconducting materials can conduct electronic signals, carried by either electrons or their positively charged counterparts, called holes. ‘P-type’ materials primarily use hole-driven transport, whereas ‘n-type’ materials primarily use primarily electron-driven transport, however a combination of the two, producing more sensitivity, is called ‘ambipolar’.

Research published recently in Nature Communications and reported by Imperial College London, which provided team leadership, 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, which will now be able detect positively charged sodium and potassium ions, relating to neuron activity throughout the body.