Electrochemical preparation and electrical characterization of polyaniline as a sensitive biosensor

Electrochemical biosensor has been developed for detection of danazol (Dz) based on electrochemical polyaniline (PANI) electrode. Electrochemical PANI films were prepared by electrochemical polymerization technique. The Fourier transform infrared spectroscopy and X-ray diffraction were performed to identify the characteristic peaks and the degree of crystallinity of the prepared films. Cyclic voltammetry (CV) studies have been investigated for the electrochemical polyaniline films onto carbon electrode to determine the appropriate electro-active films to be used as electrochemical biosensor. CV of electrochemical polymerization of polyaniline films at different doping concentrations of 1, 1.2 and 1.5 M. CV results shown, the maximum peak current was 44.67 mA/cm² at 0.2 V/SCE for 1 M HCl. The prepared electrodes were used for detecting Dz using differential pulse voltammetry (DPV) technique and electrochemical impedance spectroscopy (EIS). The current peak of DPV produced inside solution containing Dz of concentration 2 nM is about 1.671 mA. Also, EIS showed that the charge transfer resistance (R_ct) was increased with different Dz concentration.