ELECTROCHEMICAL SCIENCE Femtogram Electroanalytical Detection of Prostatic Specific Antigen by Brdicka Reaction

Abstract

Prostatic-specific antigen is considered as the best marker for prostate cancer. Due to the importance of PSA for diagnostic purposes it is not surprising that there are tested and optimized various methods for its determination. In spite of such intensive research in the field of electrochemical detection of some by-products connected with concentration of PSA, electrochemical behaviour of PSA has not been studied yet. The aim of this study was to investigate electrochemical catalytic signals of PSA using differential pulse voltammetry Brdicka reaction. The catalytic signals were studied using adsorptive transfer stripping technique as well as directly in the electrochemical cell. Nevertheless, we primarily tested detection of PSA by standard immunoanalysis and by gel and capillary chip electrophoresis to investigate behaviour of this protein in electric field. Both electrophoretic methods showed that the most intensive band of PSA was determined at 37 kDa under reducing conditions and at 26 kDa under non-reducing. Band at 37 kDa corresponds to a reduced, and at 26 kDa to non-reduced PSA. Studying of basic electrochemical behaviour of PSA was primarily carried out using standard electrochemical cell and HMDE as a working electrode. Co(NH 3