Determination of rutin on the poly(p-aminobenzene sulfonic acid) modified glassy carbon electrode.

The electrochemical behaviors of rutin at a poly(p-aminobenzene sulfonic acid) modified glassy carbon electrode (PABSA/GC) have been investigated. Rutin can generate a pair of well-defined redox peaks at the PABSA/GC located at 0.440 V (E(pa)) and 0.396 V (E(pc)) (vs. saturated calomel electrode (SCE)), respectively. The results indicate that the reaction involves two electrons transfer, accompanied by two protons and the electrochemical process is controlled by adsorption. The electrochemical parameters of rutin on the modified electrode were calculated with the results of the charge transfer coefficient (alpha), the number of electron transfer (n) and the electrode reaction rate constant (k(s)) as 0.61, 2.08 and 2.18 s(-1), respectively. Under the selected conditions, the oxidation peak current was linear to the rutin concentration over the range of 2.5x10(-7)-1.0x10(-5) M with a detection limit of 1.0x10(-7) M. The proposed method has been successfully applied to the determination of compound rutin tablets with no interference from the coexisting ascorbic acid.