单扫描示波极谱法测定甘草酸

Determination of Glycyrrhizic Acid bySingle-sweep Oscillopolarography

本文报道测定甘草酸的单扫描示波极谱方法。在０．１ｍｏｌ／ＬＮａＡｃ－Ａｃ（ｐＨ４．１±０．１）缓冲液中，甘草酸还原波峰电位为－１．３８Ｖ（ｖｓ．ＳＣＥ），峰高与其浓度在２。０×１０￣（－６）～１．０×１０￣（－４）ｍｏｌ／Ｌ范围内有线性关系，检测限为１．２×１０￣（－６）ｍｏｌ／Ｌ。甘氨酸、半此氨酸等不干扰测定。应用本方法测定强力宁注射液中甘草酸含量，结果令人满意。本文还讨论了电极过程机理。

method for the polarographic determi-nation of glycyrrhizic acid(Ⅰ)is described.In0.1mol/L NaAc-HAc(pH4.1±0.1)buffersolution,the peak potential of Ⅰis一1.38 V(vs.SCE),the peak height of I is linearly pro-portional to its concentration in the rangefrom 2.0×10￣(-6) to 1.0×10￣(-4) mol/L Accom-panying components such as glycine,cysteinedonot interfere.The method was used to de-termine the content of I in Potenlin injectionwith satisfactory results.