Development of Titania Nanotube-based Electrochemical Immunosensor and Determination of Prostate Specific Antigen

Early diagnosis of cancer is the most important factor that increases the success of treatment. Therefore, the development of new diagnostic tools is a necessity. In this study, a new electrode surface was developed via modification of a disposable titanium electrode with anodic oxidation and coating of gold nanoparticle and chitosan. Titanium electrodes were anodized by several anodization parameters to obtain a nanoporous surface and characterized by scanning electron microscopy. Electrodes anodized in optimum conditions were modified with gold nanoparticles and chitosan for enhancing conductivity and functionalizing the surface of electrode, respectively. To detect prostate specific antigen (PSA), anti-PSA was bound onto the functional electrode surface. Modified electrodes were characterized with scanning electron microscopy and cyclic voltammetry and used for chronoamperometric detection of PSA. Limit of detection (LOD) of the designed electrode was found to be 7.8 ng mL^-1 for PSA in a linear range of 0 - 100 ng mL^-1.