盐酸吡哆辛在聚对氨基苯磺酸修饰电极上的电化学行为与测定

通过电聚合法制备了聚对氨基苯磺酸(PABSA)修饰玻碳电极(GCE),采用循环伏安法(CV)和差分脉冲伏安法(DPV)研究了盐酸吡哆辛(VB₆)在该修饰电极上的电化学行为。 结果表明,VB₆在该修饰电极上的氧化电流显著增加,为裸电极上的7.5倍。 在pH值3.06.5的醋酸缓冲溶液中,VB₆在PABSA/GCE上的电极反应为吸附控制的一电子两质子的不可逆氧化反应。 在优化条件下,使用DPV对VB₆进行了定量检测,线性范围为0.04100 μmol/L,检出限为0.01 μmol/L,是目前所报道的电化学方法测定VB₆的最低检出限,相对平均偏差为3.1%(n=8)。 采用本方法对维生素B₆片中的VB₆进行检测,回收率为106%~108%。

Electrochemical Behavior and Determination of Pyridoxine Hydrochloride at Poly p-Aminobenzene Sulfonic Acid Modified Electrode

A poly p-aminobenzene sulfonic acid(ABSA) modified glassy carbon electrode(GCE) was prepared by electroploymerization. The electrochemical behavior of pyridoxine hydrochloride(VB₆) was studied by cyclic voltammetry(CV) and differential pulse voltammetry(DPV) on the modified electrode. The results show that the oxidation current of VB₆ on the modified electrode increases remarkably 7.5 times as that on the bare GCE. The electrode reaction of VB₆ on PABSA/GCE is an diffuse-limited irreversible oxidation process involving one electron and two protons in the pH 3.06.5 acetate buffer. Under optimized conditions, DPV was utilized for the measurement of VB₆. The linear range for the quantitative determination of VB₆ is 0.04100 μmol/L and the limit of detection is 0.01 μmol/L. This is the lowest detection limit of the known reported electrochemical analytical methods for the determination of VB₆. The proposed method was applied to the analysis of VB₆ tablets rapidly with recoveries between 106% and 108%.