Label-free Detection of Antibody-Antigen Interaction by Si Nanowire MOSFET

We have fabricated Si nanowire transistors for protein detection using an SOI wafer and ultra-thin hafnium oxides as a gate dielectric. When a self-assembled monolayer is formed using a ProLinker on the gate dielectrics, the conductance of a transistor increases, and further attachment of hlgG protein on the surface does not noticeably change the conductance. By contrast, additional immobilization of anti-hlgG protein over the hlgG has reduced the conductance by anti body-antigen interaction and has exhibited the largest conductance change. These results confirm that this device has recognized a specific protein reaction through direct electrical detection.