Abstract:

A glassy carbon electrode modified with hydrophobicity 1-n-butyl-3-methylimidazolium hexafluorophosphate([BMIM]PF₆/GCE) was fabricated. In a 0.2 mol/L phosphate buffer solution(pH 4.0～8.0), cyclic voltammetry and differential pulse stripping voltammetry were used to investigate the electrochemical behavior of luteolin at the modified electrode and a new method for detection of luteolin was established. As a result, an improved response of luteolin at the modified electrode was observed with peak potential shift negatively and increase of peak current. An electrocatalytic quasi-reversible redox process of controlled by absorption was obtained for luteolin on the surface of the modified electrode in a potential range of -0.2～0.7 V at pH=7.0. The charge transfer coefficient(α) and adsorbed amount(Γ) were calculated to be 0.5 and 4.6×10-10 mol/cm², respectively. The anodic current increased linearly with luteolin concentration in a range of 1.0×10^-10～1.6×10^-8 mol/L with a detection limit of 3.2×10^-11 mol/L, and the recovery is between 98.7% and 102.0%. The method is simple, quick, accurate and reliable. It may provide a novel way for flavonoid determination in wild chrysanthemum flower.

Key words: luteolin, ion liquid, modified electrode, flavonoid, electrochemistry