A molecularly imprinted electrochemical nanobiosensor for prostate specific antigen determination

Prostate Specific Antigen (PSA) is a biomarker employed for detection of prostate cancer. An electrochemical nanobiosensor is designed and fabricated using a molecularly imprinted polymer for the simple and fast PSA detection. The imprinted polymer served as a PSA artificial receptor fabricated by electrochemical polymerization of pyrrole on screen-printed gold electrode in the presence of PSA. PSA was a molecular template for the polymer. The fabricated nanobiosensor was evaluated by differential pulse voltammetry and using K₃[Fe(CN)₆]/K₄[Fe(CN)₆] as an electrochemical marker. The factors influencing the performance of the sensor including electropolymerization cycle umbers (to control the thickness of the polymer film) and time of PSA binding were optimized to attain the best sensitivity. The binding affinity of the nanobiosensor surface was examined by the Freundlich isotherm with Freundlich constant and exponent of 0.89 ng mL^-1 and 10.93, respectively. The nanobiosensor demonstrated a fast rebinding rate and a high capacity of PSA recognition with detection limit of 2.0 pg mL^-1.