Square Wave Voltammetric Determination of Rutin with Ionic Liquid Modified Carbon Paste Electrode

An ionic liquid, namely 1-amyl-3-methylimidazolium bromide (［AMIM］Br), used as electroactive material to modify carbon paste electrode (IL/CPE), was prepared, and electrochemical behavior of this modified electrode was studied by cyclic voltammetry and square wave voltammetry in B-R buffer solution of pH 3.29. It was found that a pair of reversible oxidation and reduction peaks of rutin was obtained at IL/CPE, with potential difference of oxidation peak and reduction peak attained to a value of 0.055 V. Linear relationship between values of reduction peak current and concentration of rutin was obtained in the range of 2.0×10-8-1.0×10-5mol·L-1, with detection limit (3S/N) of 1.0×10-8mol·L-1. Test for precision was performed with 8.0×10-7mol·L-1 rutin standard solution for 6 determinations, value of RSD found was 1.6%. The proposed method was applied to the determination of rutin in urine, giving values of recovery in the range of 98.3%-102.2%.