Abstract: Methods for using nanowire sensors are described. In one embodiment, the nanowire sensor may be field effect transistor having a nanowire and a functionalized control electrode. One method of using such a nanowire sensor includes exposing the functionalized control electrode to a test sample and an enhancing reagent. In another embodiment, the nanowire sensor may be a field effect transistor having a gate electrode and a functionalized nanowire. One method of using such a nanowire sensor includes exposing the functionalized nanowire to a test sample and an enhancing reagent. The use of an enhancing reagent increases the sensitivity of the nanowire sensor to a substance to be detected or quantified.