In this work, InO electrolyte gated thin film transistors (InO-EGTFTs) with integrated on-chip gate electrode were investigated as a label-free biosensor. The InO channel works as sensitive membrane and the on-chip gate electrode replaces reference electrode. The pH sensitivity of the device is 64 mV/pH with the deviation of 10 mV. The InO channel was coated by streptavidin/neutravidin receptors to detect the target biomolecules of biotin. The streptavidin modified device presents an ultra-low working voltage ( [Formula: see text] V, [Formula: see text] mV) and the detection limit as low as 50 pg · mL . And the neutravidin modified device presents apparent detecting performance even in low biotin concentration of 50 fg · mL under a working voltage of [Formula: see text] V and [Formula: see text] mV. This work provides a high-performance biosensor device with low power consumption and simple structure that is easy to integrate and package.
