苦参碱类生物碱在玻碳电极上的直接电化学行为及电分析方法研究

Study on direct electrochemical behaviors and the electroanalytical method of matrine type alkaloids at glassy carbon electrode

目的:研究苦参碱类生物碱(苦参碱,氧化苦参碱,槐定碱和氧化槐定碱)在玻碳电极上的直接电化学行为,对样品中苦参碱、槐定碱进行含量测定。方法:运用循环伏安法和方波伏安法测定它们在0.15mol·L-1NaCl水溶液中的电化学行为,并用方波伏安法进行样品含量测定。结果:玻碳电极上苦参碱和槐定碱在0.81V和0.92V附近均产生1个不可逆氧化峰,并且在一定条件下电极反应为扩散步骤控制,在相同条件下氧化苦参碱和氧化槐定碱均无氧化峰出现。运用方波伏安法测得了苦参碱和槐定碱的浓度线性范围,分析了相应药品中苦参碱和槐定碱的含量。结论:在固体玻碳电极上运用直接电化学方法测定苦参碱和槐定碱含量的精密度和准确度符合测定要求,测定结果令人满意。

Objective: To investigate the direct electrochemical behaviors of matrine(MT), oxymatrine(OMT), sophoridine(SR) and oxysophoridine(OSR) at a glassy carbon electrode in a physiological medium, and to determine the contents of commercial MT and SR pharmaceutical products were determined. Method: Their electrochemical behaviors and contents in 0.15 mol·L^(-1) NaCl aqueous solutions were obtained by cyclic voltammetry(CV) and square wave voltammetry(SWV) methods. Result: The electrochemical experimental results show that the two totally irreversible oxidation peaks for both MT and SR were observed, which potential values are 0.81 V and 0.92 V, and the electrode reaction processes were diffusion-controlled. But for both OMT and OSR, they have no oxidation peaks observed in the same condition as well. The linear range of the concentration of MT and SR and the contents in their products were obtained by SWV. Conclusion: The research results can be applied in determination of the contents of commercial MT and SR pharmaceutical products.