Аннотация:We report on label-free and fast assay based on NW FET for detection of PSA in human serum. Functionalization of NWs was performed by a new method using GOPS-SH and 5 nm GNPs, which provides oriented covalent attachment of antibody halffragments via their thiol groups. We use the GNPs to increase the effective surface of the silicon nanowires and surface-tovolume ratio, which resulted in high sensitivity to pH and improved electrical performance of the transistor. NW FETs demonstrated high sensitivity and the widest range of detectable PSA concentrations. The presented biosensor was applied to human serum samples with different PSA content, yielding promising results for use in real sample assessment. The sensitivity achieved by the biosensor was 2 orders of magnitude higher than the well-established ELISA method.