A glucose biosensor based on piezoresistive microcantilevers

A microcantilever-based biosensor with self-sensing piezoresistors integrated is developed for glucose detection. The microcantilevers were fabricated using a series of bulk silicon process. The glucose detection was achieved by immobilizing a self-assembled monolayer of 4-mercaptophenylboronic acid (4-MPBA) on the surface of a gold-coated microcantilever (sensing cantilever) and then detecting the mechanical bending induced by the glucose capture using a Wheatstone bridge. The relationship between cantilever bending and glucose concentration was obtained at glucose concentrations of 5mM and 25mM. Experimental results demonstrated that the magnitudes of bending are proportional to the glucose concentrations and the device is sensitive enough for the glucose trace detection.