Determination of the stability and stoichiometry of p-methyl red inclusion complexes with γ-cyclodextrin

被引：35

作者：

Tawarah, KM ^{[1
]}

Khouri, SJ ^{[1
]}

机构：

[1] Yarmouk Univ, Dept Chem, Irbid, Jordan

来源：

DYES AND PIGMENTS | 2000年 / 45卷 / 03期

关键词：

inclusion complexes; cyclodextrins; stability constants; p-methyl red; gamma-cyclodextrin;

D O I：

10.1016/S0143-7208(00)00024-3

中图分类号：

O69 [应用化学];

学科分类号：

081704 [应用化学];

摘要：

The effect of cyclomaltooctaose (gamma-cyclodextrin, gamma CD) on the UV-visible spectrum of p-methyl red {4-[4-(dimethylamino) phenylazo] benzoic acid} in alkaline and acidic aqueous solutions was analyzed according to a 2:1 (dye:gamma CD) inclusion process. The inclusion process in acidic solutions was studied at different ionic strengths. The values of the Gibbs free energy, Delta G(0), obtained in alkaline and acidic solutions indicate that the 2:1 inclusion complex of the cation form of the dye is more stable than that of the anion form. The values of the thermodynamic parameters Delta H-0 and Delta S-0 of the inclusion process are given for both media. The formation of the 2:1 inclusion complexes is exothermic and entropy stabilized. (C) 2000 Elsevier Science Ltd. All rights reserved.

引用

页码：229 / 233

页数：5

共 20 条

[1]

COLOR-CHANGE AND TAUTOMERISM OF SOME AZO-INDICATORS ON COMPLEX-FORMATION WITH CYCLODEXTRINS [J].