Highly sensitive protein functionalized nanostructured hafnium oxide based biosensing platform for non-invasive oral cancer detection

摘要

We report results of the studies relating to the development of a non-invasive, label free immunosen-sor based on nanostructured hafnium oxide (hafinia) deposited onto indium tin oxide (ITO) coated glass for oral cancer biomarker (CYFRA-21-1) detection in human saliva. The nanostructured haf-nia (nHfO_2) has been synthesized via one step low temperature hydrothermal process and modified with 3-aminopropyltriethoxy silane (APTES) for covalent immobilization of monoclonal antibodies (anti-CYFRA-21-1). Bovine serum albumin (BSA) was used to block non-specific sites at the anti-CYFRA-21-l/APTESHfO_2/ITO electrode surface. The structural, morphological and spectroscopic characterization of the synthesized nanomaterials and fabricated electrodes has been carried out usingX-ray diffraction (XRD), transmission electron microscopy (TEM), Fourier transform infrared spectroscopy (FT-1R) and X-ray photoelectron spectroscopy (XPS) studies, respectively. The results of response studies conducted on BSA/anti-CYFRA-21-1/APTESHfO_2/ITO immunoelectrode reveal that this biosensor has high sensitivity (9.28μAmLng~(-1) cm~(-2)), wide linear detection range (2-18ngmL~(-1)) and fast response time (15 min). This immunosensor has been validated with enzyme linked immunosorbent assay (ELISA) in saliva samples of oral cancer patients.