β-环糊精的KI-I_2分光光度法测定

Spectrophotometric Determination of β-Cyclodextrinin in Water with KI-I_2 Chromogenic System

基于β-CD引起KI-I2混合液光谱变化的原理,获得了β-CD的KI-I2分光光度测定法,并分析了不同实验条件对测定结果的影响。结果表明,以KI-I2溶液为显色剂的分光光度法测定波长为430 nm,显色时间为30 min,工作曲线相关系数为0.999 7,检测范围为0.74-75 mg/L,pH 5-9范围内测定效果好,操作简单,共存的不水解、易水解无机盐及水体腐殖酸对测定的干扰小。利用KI-I2分光光度法测定β-CD在土壤中等温吸附曲线,获得了较满意的效果。

Based on the principle β-CD induced the spectral changes of KI-I2 chromogenic system,the method KI-I2 spectrophotometry used to determine β-CD in water had been investigated. In addition,the effect of different experiment conditions on the determination of β-CD was discussed. The results showed that the wave length for determination of β-CD was 430 nm,the reactive time with KI-I2 developer was 30 min and p H was 5 ~ 9,respectively. The work curves of β-CD was highly linear（ correlation coefficient was 0. 999 7） and the linear range was 0. 74 - 75 mg / L. Moreover,the spectrophotometric method was free from interference by metal ions and humic acid in water. The determination method was successfully used in the determination of adsorption isotherm of β-CD on soils.