Microelectronics meets biomedicine: Integrated MOSFET-embedded cantilever sensor and diagnostics system

Recent advances in nanotechnology promise considerable and realistic potential for the development of innovative and high performance sensing and diagnostic approaches in biomedical field. In particular, the microcantilever detection paradigm based on direct transduction of molecular binding induced surface stress into a nanomechanical motion of microcantilevers, has attracted considerable attention for label-free detection of biomolecules. As an alternative to the currently deployed optical, piezoresistive, and capacitance nanomechanical detection techniques, we introduce a new electronic transduction paradigm comprising two-dimensional microcantilever arrays with geometrically configured metal-oxide-semiconductor-field-effect-transistors (MOSFETs) embedded in the high stress region of the microcantilevers. We have shown that the deflection of the microcantilever induced by specific ligand-analyte binding events leads to a precise, measurable and reproducible change in the drain current of the MOSFET buried in the microcantilevers. High current sensitivity of MOSFET- embedded platform enables detecting nanoscale cantilever deflection from specific biomolecular binding events at very low concentration of analytes with sensitivity in the parts-per-trillion (ppt) range. We have shown ultra-sensitive detection of streptavidin-biotin based biomolecular interactions and biomarkers for cardiovascular diseases. Our novel detection mechanisms offer an excellent platform for variety of different biomolecular sensing applications, ranging from clinical diagnostics and environmental monitoring to drug discovery, as well as gas and chemical sensing by integrating receptors on MOSFET cantilevers.