Glucose Biosensor Based on MWCNTs-Gold Nanoparticles in a Nafion Film on the Glassy Carbon Electrode Using Flow Injection FFT Continuous Cyclic Voltammetry
A new glucose electrochemical biosensor was designed using a flow injection system. Glucose oxidase (GOx), as a sensing material, was immobilized on to the modified surface of a glassy carbon electrode using nafion polymeric matrix. Gold nanoparticles (AuNPs) and multiwall cabon nanotubes (MWCNTs) were used to modify the surface of the glassy carbon electrode and improve the biosensor response. Fast Fourier transformation continuous cyclic voltammetry (FFTCCV) was used as detection method in which the charge under the peak calculated in a specific potential range. Ferrocene methanol in PBS buffer (pH=7.0) was used as the flowing eluent. It is a pair of well-reversible redox reagent which is used as an electron-transfer mediator. Effect of scan rate, solution flow rate and buffer pH were also studied. The results show that, the linear response range of biosensor was in the range of 0.1 to 10 mu M and the detection limit was calculated 0.03 mu M at a signal-to-noise ratio of 3. The proposed biosensor showed an acceptable reproducibility, good stability and low interferences.