摘要
在Ｈ３ＢＯ３Ｎａ２Ｂ４Ｏ７（ｐＨ８５）底液中，大黄素在单扫示波极谱仪上于－０７５Ｖ（ｖｓ．ＳＣＥ）左右有一灵敏的二阶导数峰，峰电流与浓度在１４２×１０－７～５７×１０－６ｍｏｌ·Ｌ－１和７１×１０－６～７１×１０－５ｍｏｌ·Ｌ－１范围内呈良好的线性关系，检测限为０７×１０－７ｍｏｌ·Ｌ－１。本法操作简便、快速、灵敏、选择性好，应用于中药大黄中大黄素的测定，结果良好。本文还研究了大黄素的极谱行为及电极反应机理，并用电化学方法讨论了大黄素、大黄酸、大黄酚、大黄素甲醚和芦荟大黄素清除由邻苯三酚自氧化产生的超氧自由基（Ｏ·－２）的作用。
Emodin showed a second order derivative reduction wave with peak potential of -0 75 V(SCE) by single sweep oscillopolarography using H 3BO 3 Na 2B 4O 7 (pH 8 50) as base solution. The peak height of emodin is proportional to the concentration in the range of 1 42×10 -7 ～5 7×10 -6 mol·L -1 and 7 1×10 -6 ～7 1×10 -5 mol·L -1 , respectively. The detection limit is 0 7×10 -7 mol·L -1 . It can be employed for the determination of emodin in Rheum officinale Baill with satisfaction. The electrochemical behavior of emodin was studied and the electrode reaction mechanism was proposed. In addition, it was found that emodin, aloe emodin, chrysophanol, rhein and physcion can scavenge superoxide anion radical produced by the autoxidation of pyrogallol. The scavenging activity is in the order: emodin>aloe emodin>chrysophanol>rhein>physcion.
出处
《药学学报》
CAS
CSCD
北大核心
1997年第4期310-313,共4页
Acta Pharmaceutica Sinica
基金
国家自然科学基金
中科院长春应化所电分析化学开放实验室基金
关键词
大黄素
超氧自由基
极谱法
中药
Emodin
Superoxide anion radical
Polarography
