Electrochemical Behavior of Luteolin and Application to Its Determination

Electrochemical behavior of luteolin in an unitary aqueous medium was studied.It was found that a reversible and well-shaped symmetrical redox peak of luteolin was obtained in a base solution of B-R buffer of pH 4.0.As shown by the results of CV study,the electrode reaction of luteolin on the surface of the glassy carbon electrode was controlled by adsorption.The relationship between anodic peak current ipa and concentration of luteolin cLu as studied by DPV,was found in the range of 8.0×10-8-8.0×10-6mol·L-1,with detection limit (3S/N) of 7.14×10-8mol·L-1,and recovery in the range of 98.5%-104.0%.Value of ipa attained to a maximum when cLu was 4.14×10-5mol·L-1 (as tested by LSV),and the max.adsorption coverage ΓT of 6.21×10-10mol·cm-2 was found by the formula Q=nFAΓT.Based on the principle of Laviron and the Langmuir isothermal adsorption equation,the following dynamic parameters of the electrode process are found: n=2,=2,a=0.90 and ks=2.96 s-1.A brief discussion on the mechanism of the electrode reaction was also given.