Highly sensitive and label-free electrochemical biosensor based on gold nanostructures for studying the interaction of prostate cancer gene sequence with epirubicin anti-cancer drug

A label-free electrochemical DNA hybridization biosensor was developed based on gold nanocubes (AuNCs) modified graphite screen-printed electrodes (GSPEs) for investigating the epirubicin (EPI) interaction with the short sequence DNA of prostate cancer gene. The electrochemical behavior of the genosensor was assessed in different steps of construction using cyclic voltammetry and electrochemical impedance spectroscopy methods. The changes in the biosensor responses versus the DNA interactions with the various concentrations of EPI were monitored by the differential pulse voltammetry method. The reduction peak current of EPI linearly increased with the increasing concentration of EPI. Under optimal conditions, two linear ranges were obtained from 0.04 to 0.80 mu M and 0.8 to 20.0 mu M, respectively with a limit of detection 0.01 mu M. The prepared biosensor exhibited a proper selectivity toward the target drugs. The applicability of the sensor was demonstrated by the explored of epirubicin in a human blood serum sample. In addition, the prepared biosensor was used as a reproducible and stable device for EPI determination.