芦荟大黄素的电化学研究

Investigation on Electrochemical Behavior of Aloe-emodin

用单扫示波极谱法研究了芦荟大黄素的电化学行为。在５％Ｎａ２ＣＯ３＋５％ＮａＯＨ（９＋１）底液中，芦荟大黄素于－０．８４Ｖ（Ｐ１）和－０．９７Ｖ（Ｐ２）处产生两个示波极谱峰，利用Ｐ１可测定芦荟大黄素，线性范围为 ０．１１－２４ｍｇ／Ｌ和３．０－２８．６ｍｇ／Ｌ，检测限为０．０６ｍｇ／Ｌ。将该法应用于中药大黄中的芦荟大黄素的测定，结果满意。另外，讨论了芦荟大黄素清除由邻苯三酚自氧化产生的超氧自由基（Ｏ２）的作用。

The electrochemical behavior of aloe-emodin is studied by single sweep oscillopolarography. Aloe-emodin shows two reduction waves and the peak potentials are - 0.84 V(P1)and - 0.97 V(P2)respetively,using 5% Na2CO3 + 5% NaOH(9 + 1 )as a base solution.The peak height of the first wave(P1) is proportional to the mass concentration in the range of 0.11 - 2.4 mg/L and 3.0 - 28.6mg/L, respechtively. the deception limit is 0.06mg/L. It is employed for the detendnation of aloe-emodin in Rheum officinale Baill with satisfaction. In addition, it is discussed that aloe-emodin can scavenge superoxide anionradical produced by autoxidation of pyrogallol.