Measuring the Electrical Activity of Cardiomyocytes Using Electrolyte-Gated Organic Thin Film Transistors

Dinaphtothienothiophene (DNTT) based semiconductors have been used in state-of-the-art organic thin film transistors, exhibiting high mobility, high stability, and low contact resistance relative to other organic materials.^1,2 However, such devices have not been utilized for the direct sensing of cells. In this work, we demonstrate DNTT-based, electrolyte-gated field effect thin film transistors (EGOFETs) as sensors that measure the activity of induced pluripotent cardiomyocytes. Cells are placed directly onto the channels of the transistors, modulating the gate voltage as they spontaneously contract. EGOFETs have very high gate capacitance, so the small variations induced by cellular activity generate large variations in the drain current. Arrays of transistors are used to map conduction across in vitro cardiomyocyte tissue. We also study the electrical properties of DNTT-based EGOFETs, demonstrating their high mobility and low contact resistance even when in contact with an electrolyte. Through these experiments, we show that DNTT-based EGOFET arrays are a promising new platform for bioelectric sensing.

(1) Borchert, J.; Weitz, R. T.; Ludwigs, S.; Klauk, H. A Critical Outlook for the Pursuit of Lower Contact Resistance in Organic Transistors. Adv. Mater. 2022, 34 (2104075).

(2) Zschieschang, U.; Waizmann, U.; Weis, J.; Borchert, J.; Klauk, H. Nanoscale Flexible Organic Thin-Film Transistors. Sci. Adv. 2022, 8 (13).