Immobilization of proteins on semiconductor nanowires for biosensor development

Silicon (Si), silicon carbide (SiC), gallium nitride (GaN), zinc oxide (ZnO) and other semiconductor nanowires (NWs) show great promise as sensing elements for the electrical detection of biomolecules [1-3]. In order to enable chemiresistor-type NW devices that utilize direct electronic sensing of biomolecules, one must first develop an analyte-specific functionalization of the nanowire surface and deduce mechanisms by which the functional and analyte molecules bind to the surface. Here we present a solution based bioconjugation technique for the attachment of protein molecules to the NW surfaces. Example of selective immobilization of streptavidin on biotinylated Si, SiC, and GaN NWs was studied and verified by a suite of surface characterization techniques.