Analytical Sciences

Abstract − Analytical Sciences, 21(10), 1223 (2005).

Electrochemical Behavior and Detection of Plant Hormone 6-Benzyl Adenine in Acetate Buffer at Mercury Electrode
Xiang-Jin QU, Jie ZHOU, and Ji-Gang GAO
College of Chemistry and Material Science, Shandong Agricultural University, Taian 271018, P. R. China
The electrochemical behavior of 6-benzyl adenine (6-BA) has been studied in 0.1 mol L-1 HAc-NaAc solution (pH 3.8). Cyclic voltammetry, single-sweep polarography and direct current polarography were employed to clarify the mechanism of the electrode process; the kinetic parameters of the rate-determining step were determined. Reduction of 6-BA involves two pH-dependent processes, corresponding to the overall irreversible reduction of the 1,6 and 3,2 N=C bonds. Each reduction stage consists a preprotonation of the nitrogen atom at the electroactive site and a rapid two-electron transfer. In the presence of 6-BA, the reduction potentials of some ions were shifted. Under the given conditions, 6-BA displays one irreversible reduction peak controlled by adsorption. Two linear response were observed in the range 2.0 × 10-8 - 8.0 × 10-7 mol L-1 and the range 1.0 × 10-6 - 8.0 × 10-6 mol L-1, with correlation coefficients of 0.9995 and 0.9998, respectively. The detection limit is 7.1 × 10-9 mol L-1. The method had been applied to the determination of 6-BA in bean sprout samples with satisfactory results.