DNA Biosensor for Determination of 5-Fluorouracil based on Gold Electrode Modified with Au and Polyaniline Nanoparticles and FFT Square Wave Voltammetry

In the present study, a new biosensor for 5-fluorouracil was described using modified gold electrode and fast fourier transform square wave voltammetry (fft swv). calf thymus dna immobilization was on a gold electrode decorated with polyaniline and gold nanoparticles. the electrochemical characteristics of the electrodes were investigated by cyclic voltammetry, and electrochemical impedance spectroscopy. after interaction dna with the analyte, a dramatic decline in [fe(cn)6]/[fe(cn)6]]^3-/4- signal was observed which could be used as the signal. the important parameters of the detection system, such as, ph were optimized. the linear dynamic range of the biosensor was1×10^-9 to 1×10^-6 m (r^2=0.996) limits of detection of 2.5×10^−10 m. in addition to the wide linear range response, the proposed method demonstrated acceptable sensitivity, repeatability and long-term stability. future experiments could be performed to examine several other effective factors so as to decrease the influence of the environment and investigate its application to fftswv detection.