A chemical chip can control the delivery of the neurotransmitter acetylcholine, enabling chemical control of muscles.

Klas Tybrandt, a doctoral student in organic electronics at Linköping University (Sweden), has developed an integrated chemical chip that combines both ion transistors for transport of positive and negative ions and biomolecules into complementary circuits. An advantage of chemical circuits is that the charge carrier consists of chemical substances with various functions, providing new opportunities to control and regulate the signal paths of cells in the human body.

“We can, for example, send out signals to muscle synapses where the signaling system may not work for some reason," remarks Magnus Berggren, professor of organic electronics and leader of Tybrandt's research group. "We know our chip works with common signaling substances, for example acetylcholine.” 

Three years ago, Tybrandt and Berggren began to develop ion transistors, which can control and transport ions and charged biomolecules. The transistors were then used by researchers at Karolinska Institutet to control the delivery of acetylcholine to individual cells. Now, Tybrandt is developing chemical chips that also contain logic gates, such as NAND gates, that allow for the construction of all logical functions. His breakthrough creates the basis for a new circuit technology based on ions and molecules instead of electrons and holes.