Voltammetric behaviour of puerarin and its determination by single-sweep oscillopolarography

Abstract

In 0.1 mol dm^–3 H₂SO₄ solution, a sensitive reductive wave of puerarin was obtained by single-sweep oscillopolarography. The peak potential was –1.00 V (versus SCE). The peak height was proportional to the concentration of purearin over the range 4.0 × 10^–7–6.0 × 10^–6 mol dm^–3 and the detection limit was 5.0 × 10^–8 mol dm^–3. The behaviour of the reduction wave was studied and applied to the determination of puerarin in tablets. The reduction process was irreversible with the adsorptive characteristics and the behaviour obeyed the Frumkin adsorptive isotherm. The adsorption coefficient β was 1.14 × 10⁵ and the interaction factor α was 1.54.