Electrochemical Behavior of Daidzein and Its Voltammetric Determination

In a Tris-HCl buffer base solution of pH 7.5,a well-defined oxidation peak with its peak potential at 0.53 V (vs.AgCl/Ag) was observed in the cyclic voltammogram of daidzein.Linear relationship was obtained between values of peak current and concentration of daidzein in the range of 1.2×10-7-9.6×10-6mol·L-1.Detection limit (3S/N) of 8.0×10-8mol·L-1 was found for this method.Daidzein content in a sample of trifolium was determined by this method.Using this sample as matrix,recovery test was made by standard addition method,an average recovery of 98.0% was found.Test for precision was performed with 1.6×10-6mol·L-1 of daidzein,the value of RSD (n=8) found was 0.81%.It was added that the reaction of daidzein at the glassy carbon electrode was an adsorptive and irreversible process.