Electromechanical sensors that employ Janus micro/nano-components and techniques for the fabrication thereof are provided. In one aspect, a method of fabricating an electromechanical sensor includes the following steps. A back gate is formed on a substrate. A gate dielectric is deposited over the back gate. An intermediate layer is formed on the back gate having a micro-fluidic channel formed therein. Top electrodes are formed above the micro-fluidic channel. One or more Janus components are placed in the micro-fluidic channel, wherein each of the Janus components has a first portion having an electrically conductive material and a second portion having an electrically insulating material. The micro-fluidic channel is filled with a fluid. The electrically insulating material has a negative surface charge at a pH of the fluid and an isoelectric point at a pH less than the pH of the fluid.