Investigation of DNA sensing using piezoresistive microcantilever probes

Piezoresistive microcantilever-based sensors maybe used in a variety of sensing applications, including chemical sensing and biological sensing. In these applications, a sensing material is functionalized so as to undergo a volumetric or dimensional change upon analyte exposure. A piezoresistive microcantilever in contact with, or embedded within, the sensing material records the dimensional change as a simple resistance change in the cantilever as it is strained by the volumetric shift in the sensing layer. Here, we describe the detection of single-strand DNA by utilizing a sensing layer material consisting of thiolated single-strand DNA attached to a gold film substrate. A piezoresistive microcantilever in direct contact with this layer in solution immediately responds to the presence of the complimentary (25 base) single strand.