Biosensing Applications of Graphitic Carbon Nitride-Chitosan Nanosheets on Glassy Carbon Electrode for Determination of Phytic Acid Biosensor

摘要

A novel phytic acid (PA) biosensor was fabricated using phytase enzyme immobilized graphitic carbon nitride (g-C_(3)N_(4)) and chitosan (CH) on the surface of glassy carbon electrode (GCE). The electrochemical method used for determination of phytic acid was strippingcyclic voltammetry (CV) and differential pulse voltammetry (DPV). The synergistic effect of g-C_(3)N_(4)-CH/phytase made the biosensor to possess the excellent activity toward the oxidation of the analyte in acetate buffer in pH 5.0. The biosensor exhibited a linear responseto phytic acid as substrate from 5.0 to 25 ppm with correlation confectioned (R ~(2) = 0.97) and limit of detection (LOD) of 2.0 ppm phytic acid at optimum pH 5.0 in 0.1 M acetate buffer. In addition, the biosensor excludes interfering substance, which makes the biosensor possessesthe requisite accuracy and sensitivity to assay phytic acid in corn flour samples.