Nanomechanical protein detectors based on the mechanical property measured by nano-gap actuators

This paper presents a new method and an associated device for detecting the presence and size of protein based on a protein-induced stiffness change. Compared to the conventional mechanical method, the present nanomechanical method shows higher precision. The present method also offers simple and inexpensive protein detection by removing labeling process and optical components. We design and fabricate the nanomechanical protein detector using an electrothermal actuator and a nano-gap. In experimental study, we measure two stiffness changing points and their coordinate shift between two cases (without/with target proteins). The fabricated device detects the protein presence and size of 14.0 ± 7.4 nm from this coordinate shift of stiffness changing points. Therefore, we experimentally verify the high-precision protein sensing capability of the nanomechanical protein detector.