The observed increase of current by adding glucose is the result of higher charge carrier density produced by GOx-catalyzed glucose reaction with water and oxygen on the ZnO surface. In this reaction, H 2 O 2 is produced and injects electrons onto the n-type ZnO nanowire, increasing its conductivity [72]. This response can be further enhanced by strain through the piezotronic effect at the reversed-bias Schottky contact, where the Schottky barrier is dominant in the charge transport process throughout the device. With the c-axis pointing toward the source and the nanowire being under compression, non-mobile ionic positive charges accumulate at the drain and tune the Schottky barrier height at the interface between the n-type ZnO nanowire and silver. Since the current response is exponentially dependent on the barrier height, it can be significantly tuned by the applied strain to the high sensitivity range for glucose sensing as demonstrated by the experimental results