A Sensitive Biosensor for Acrylamide Detection based on Polyaniline and Au Nanoparticles using FFT Admittance Voltammetry

A new electrochemical detection system was developed based on combination of a biosensor and Fast Fourier transform Admittance Voltammetry (FFTAV), which used for the sensitive detection of acrylamide. By effective self-assembling process, the biosensor was prepared of thiol functionalized single-stranded DNA (ssDNA) on gold nanoparticles, which deposited on a gold electrode decorated with polyaniline. The acrylamide has the ability to form a single complex with ssDNAs, which was linked on the biosensor surface, and changed the admittance of the electrode. Therefore, the concentration of acrylamide was detected directly by the change of admittance of the electrode. The biosensor was characterized by Scanning electron microscope-based (SEM), electrochemical impedance spectroscopy copy (EIS) and cyclic voltammetry. Under optimal conditions, the linear dynamic range of the acrylamide was 5.0×10-10 M to 2.0×10-7 M (r2 = 0.988) limits of detection of 5.0×10-11 M. The data showed that the electrochemical biosensor could detect acrylamide rapidly and accurately. Moreover, the proposed method demonstrated acceptable sensitivity and long-term stability.