High-performance electrolyte-gated amorphous InGaZnO field-effect transistor for label-free DNA sensing

Accurate, convenient, label-free, and cost-effective biomolecules detection platforms are currently in high demand. In this study, we showcased the utilization of electrolyte-gated InGaZnO field-effect transistors (IGZO FETs) featuring a large on-off current ratio of over 106 and a low subthreshold slope of 78.5 mV/dec. In the DNA biosensor, the modification of target DNA changed the effective gate voltage of IGZO FETs, enabling an impressive low detection limit of 0.1 pM and a wide linear detection range from 0.1 pM to 1 μM. This label-free detection method also exhibits high selectivity, allowing for the discrimination of single-base mismatch. Furthermore, the reuse of gate electrodes and channel films offers cost-saving benefits and simplifies device fabrication processes. The electrolyte-gated IGZO FET biosensor presented in this study shows great promise for achieving low-cost and highly sensitive detection of various biomolecules.