双等色点光度法测定姜黄素-铁(Ⅱ)的稳定常数及试验方法改进

Dual Isosbestic Points Spectrophotometric Determination of Stability Constant of Curcumin-Fe(Ⅱ) Complex and Modification of the Test Method

摘要: 采用双等色点光度法测定姜黄素-铁(Ⅱ)络合物的稳定常数并对试验方法进行了改进。采用两种紫外-可见分光光度法设计试验方案,考察了姜黄素的光谱特性,获得姜黄素与铁(Ⅱ)的络合物吸收光谱中两个等色点,姜黄素-铁(Ⅱ)络合物的稳定常数为1.48×1011(pH 6.50),改进后试验方法的稳定常数为1.49×1011。

Abstract: Dual isosbestic points-spectrophotometry was applied to the determination of stability constant of curcumin-Fe(Ⅱ) complex and the testing method was improved. The spectral characteristics of curcumin were investigated by two experimental programs of UV-visible spectrophotometry. Two isosbestic points were found in the absorption spectra of curcumin-Fe(Ⅱ) complex. The stability constant of the curcumin-Fe(Ⅱ) complex was found as 1.48×1011 (at pH 6.50),and value of stability constant of complex of 1.49×1011 was obtained by the inproved method.