Nanowire Mechanical Resonators for the Specific Detection of Proteins

M. Belov, V. Wright, N.J. Quitoriano, T.I. Kamins, J. Buriak, S. Evoy
University of Alberta, CA

Keywords: nanomechanical resonators, proteins, biosensors, NEMS

Abstract:

Detection of biological and chemical agents is critical to many life sciences areas. Enzyme-linked imunosorbent assay (ELISA) is a widely employed array-based analytical technique that however requires fluorescent tagging which may disrupt the biochemical properties being investigated. Micro- and nanoresonators have been shown to be promising platforms for such tagless analysis of biomolecules. The binding of the analyte onto the sensor surface is detected through a shift of resonant frequency induced by the added mass. The sensitivities of these devices scales favourably as their mass is reduced, offering a compelling path for the development of sensors of exceptional sensitivities. We have recently reported the analysis of silicon nanowires of diameters as small as 40 nm using a simple room-temperature interferometry technique. [1] We here report the nanowire-based specific detection of proteins using such resonant nanowires. This monitoring is performed using a contact-less optical technique, and would thus be readily scalable to large arrays of devices. The specific detection of streptavidin using biotin as molecular probe is demonstrated as proof of concept.