Electrochemical Behavior of Epinephrine at a Glassy Carbon Electrode Modified by Electrodeposited Films of Caffeic Acid

摘要

A stable electroactive thin film of poly(caffeic acid) has been deposited on the surface of a glassy carbon electrode by potentiostatic technique in an aqueous solution containing caffeic acid. The voltammetric behavior of epinephrine (EP) at the poly(caffeic acid) modified glassy carbon electrode was studied by cyclic voltammetry. The poly(caffeic acid) modified electrode exhibited a promotion effect on the oxidation of EP. In a pH 7.4 phosphate buffer, the anodic current increased linearly with the concentration of EP in the range from 2.0 × 10⁻⁶ to 3.0 × 10⁻⁴ mol L⁻¹ and the detection limit for EP was 6.0 × 10⁻⁷ mol L⁻¹. The proposed method can be applied to the determination of EP in practical injection samples with simplicity, rapidness and accurate results.