吡哆醛的电化学行为研究

Investigation of Electrochemical Behavior of Pyridoxal

用单扫示波极谱法，吡哆醛在０．２ｍｏｌ／ＬＫＣｌ＋０．０２ｍｏｌ／ＬＮａＯＨ底液中，产生一良好的二阶导数峰，Ｅｐ＂＝－１．３０±０．０１Ｖ（ＳＣＥ），其峰高与浓度在２×１０－７－２×１０－４ｍｏｌ／Ｌ范围内成线性关系，检出限为１×１０－７ｍｏｌ／Ｌ．实验证明，其电极过程为伴有微弱吸附性质的可逆扩散过程（ｎ＝２）．当在弱酸性和中性介质中时，吡哆醛的电极过程为前行动力学过程，其电极反应机理为伴有双聚反应的可逆的逐级电子过程．用自由基阻聚剂能有效地抑制吡哆醛的电双聚反应。

Pyridoxal(PL) shows a 2nd order derivative reduction wave and a peak potential of -1.30±0.01v(SCE) by single sweep oscillopolarography, using 0.2mol/L KCl+0.02mol/L NaOH as base solution. The peak height is proportional to the concentration of PL in the range of 2×10 -7 -2×10 -4 mol/L. The electrode reaction of PL is two electrons reversible process under the control of diffusion with a weakly adsorptive character. In the weak acidic and neutral medium, the electrode reaction is reversible multistep charge transfer process involving dimeration reaction. The experimental results show the dimeratiom can be inhibited by free radical inhibitor. It is helpful to understand this kind of electrode process better.