Abstract
In this study, an immunosensor was designed to utilize for the detection of prostate specific antigen (PSA) based on three different generations (G1, G2 and G3) of ferrocene (Fc) cored polyamidiamine dendrimers (Fc-PAMAM) gold (Au) electrode. The self-assembled monolayer principle (SAM) was used to fabricate the sensitive, selective and disposable immunosensor electrodes. In electrode fabrication cysteamine (Cys) was the first agent covalently linked on the Au electrode surface. Immobilized redox center (ferrocene) cored PAMAM dendrimers served as a layer for the further binding of biological components. The monoclonal antibody of PSA (anti-PSA) was covalently immobilized on dendrimers which were attached onto the modified Au surface (Au/Cys/Fc-PAMAMs/anti-PSA). PSA levels were quantitatively analyzed by using electrochemical differential pulse voltammetry (DPV) whose lowest detection limit was calculated as 0.001 ng mL(-1). The Au/Cys/FcPAMAM/anti-PSA immunosensor showed excellent performance for PSA at the pulse amplitude; 50 mV and the scan rate; 10 mV/s in a wide linear concentration range of 0.01 ng-100 ng mL(-1). Analytical performance and specificity assays were carried out using human serum and different proteins. (C) 2016 Elsevier B.V. All rights reserved.