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用循环伏安法和计时库仑法研究了维生素Ｂ＿６（ＶＢ＿６）在不同ｐＨ值的磷酸盐介质中的电化学行为。结果表明：ＶＢ＿６经过一个有质子参与的４ｅ不可逆电氧化反应；在碱性和中性介质中ＶＢ＿６被电氧化为含有羰基结构的自由基；在酸性介质中ＶＢ＿６被电氧化为γ－内酯。电氧化的产物均具电活性，可分别发生两步准可逆氧化还原反应。化学鉴定实验表明在碱性和中性介质中ＶＢ＿６氧化后生成羰基化合物，而在酸性介质中ＶＢ＿６氧化后无羰基生成。紫外吸收光谱电化学实验结果表明：ＶＢ＿６在碱性和中性介质条件下随电解时间而变化的吸收光谱与在酸性介质条件下的不一样。在此基础上提出了ＶＢ＿６在不同ｐＨ介质条件下可能的电化学反应历程。
Cyclic voltammetry and chronometric coulometry were used to study the electrochemical behavior of vitamin B_6 (VB_6) in different pH values of phosphate media. The results show that VB 6 undergoes 4e irreversible electroxidation with proton participation. VB 6 is electrically oxidized to a carbonyl group-containing free radical in alkaline and neutral media. VB_6 is electrically oxidized to γ-lactone in acidic medium. Electrooxidation products are electrically active, can occur two-step quasi-reversible redox reactions. Chemical identification experiments showed that VB_6 was oxidized to produce carbonyl compounds in alkaline and neutral media, but no oxo groups were formed in VB_6 after oxidation in acidic medium. The results of UV absorption spectroscopy showed that the absorption spectra of VB_6 under alkaline and neutral conditions vary with the electrolysis time, which is different from that under acidic medium. On this basis, the possible electrochemical reaction process of VB_6 under different pH media conditions was proposed.