P-type Si-nanowire-based Field-effect Transistors for Electric Detection of a Biomarker: Matrix Metalloproteinase-9

We studied the electric detection of a biomarker by using p-type Si-nanowire-based field-effect transistors (FETs) for biological applications. A combination of electron-beam lithography and a lift-off process was utilized to fabricate individual 50-nm-thick Si nanowire FETs. The gate-dependent I - V-SD curves revealed that the conductance of a Si-nanowire FET increased with increasing negative V-G. The conductance of the Si nanowire FET depended upon the existence of negatively charged streptavidin binding to a biotin with a peptide and Matrix metalloproteinase-9 (MMP-9), cutting the peptide. Our results suggest that Si-nanowire FETs can be used to detect MMP-9 activity.