Highly sensitive, label-free and real-time detection of alpha-fetoprotein using a silicon nanowire biosensor.
Alpha-fetoprotein (AFP) is a tumor-associated fetal protein that can be expressed in large amounts in adult tumor cells, serving as a useful clinical tumor-marker. Silicon nanowire (SiNW) biosensors have emerged as a powerful tool in detecting protein biomarkers, due to their ultrahigh sensitivity, real-time response and label-free detection. We fabricated a SiNW-based field-effect transistor (FET) according to \"top-down\" methodology. First, anti-AFP antibodies were immobilized onto the surface of the SiNW-FET.