Self-n-doped small molecules for highly stable and low-power biosensing

Abstract

Minimizing power consumption and improving long-term stability of bioelectronic devices are crucial for ensuring prolonged operation and reducing the risk of tissue damage. Organic electrochemical transistors (OECTs) have gained widespread attention in biosensing applications due to their high transconductance and excellent biocompatibility. Although considerable efforts have been directed toward optimizing performance metrics (e.g. µC*) in OECTs, strategies to reduce power consumption have been largely overlooked, despite their critical importance for large-scale integration and in vivo sensing applications. Here, we present a unique self-doping strategy to achieve low power consumption in OECTs. Small molecules with certain end groups can undergo self-doping through ethylene glycol side chains, enabling n-type depletion-mode OECTs with near-zero threshold voltage (VTh) and outstanding long-term stability. Based on these, we developed biosensors with high signal-to-noise ratios while operating at an ultralow power consumption of 12 nW. Our findings highlight self-doping molecules for energy-efficient biosensing.