Abstract:Acrylamide is a neurotoxin and a potential carcinogen. Hemoglobin (Hb) biosensor passivation can be achieved by the formation of a covalent compound by acrylamide with the -NH2 group of the N-terminal valine of hemoglobin. Different concentrations of acrylamide produce different degrees of passivation. Based on this principle, hemoglobin biosensors were prepared by immobilizing multi-wall carbon nanotubes (MWCNTs) and Hb in a chitosan film on the surface of glassy carbon electrodes and these were used for the detection of acrylamide in fried food. The optimum analysis conditions for the detection of acrylamide in fried food by differential pulse voltammetry (DPV) was determined as follows: pulse increment 0.008 V, pulse amplitude 0.05 V, pulse width 0.1 V, pulse interval 0.1 s. The oxidative-reductive detector consisted of 10 μg/cm2 MWCNTs and the supporting electrolytes were 0.1 mol/L PBS (pH 7.4), 0.1 mol/L NaCl and 5×10-3 mol/L potassium ferrocyanide. The linear range of response was from 3.0×10-8 mol/L to 3.0×10-7 mol/L and the detection limit was estimated as 1.2×10-8 mol/L, taking into account a signal-to-noise ratio of 3. The developed method is practical in the determination of acrylamide in fried foods, with the advantages of simplicity, rapidity, sensitivity, and accuracy over the standard high-pressure liquid chromatography method.
