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目的定量的考察姜黄素与α,β,γ-环糊精及一系列有机硒桥连双环糊精的键合能力与包结配位行为.方法采用紫外-可见光谱滴定法测定了姜黄素在25℃时,pH=2.0缓冲溶液中与主体分子1～6形成1:1超分子配合物的稳定常数(Ks)及吉布斯自由能(△G°).结果β-环糊精对姜黄素的键合能力明显高于α,与γ-环糊精.与母体环糊精相比,具有功能桥链的有机硒桥连双环糊精通过相邻的两个环糊精空腔对一个姜黄素分子的协同键合,能够明显的扩展母体环糊精原有的键合能力,给出了比β-环糊精高2.8～17.1倍的稳定常数.结论尺寸/形状匹配及主客体间的疏水相互作用是影响主体1～6与姜黄素的键合能力和包结配位行为的关键因素.“,”Aim To investigate quantitatively the binding ability and inclusion complexation behavior of curcumin withnatural α-, β-, γ-cyclodextrins (1-3) and a series of organoselenium-bridged bis(β-cyclodextrin)s with simple spacer(4-6). Methods The spectrophotometric titrations have been performed in KCl-HC1 buffer solution(pH = 2.0) at 25℃to calculate the complex stability constants(Ks) and Gibbs free energy changes( △G°) for the stoichiometric 1: 1 inclusioncomplexation of 1- 6 with curcumin. Results The binding ability of β-cyclodextrin for inclusion complexation with guestcurcumin is higher than that of a-and γ-cyclodextrins. As compared with parent β-cyclodextrin, the organoselenium bridgedbis(β-cyclodextrin)s tethered by some functional groups can further enhance the original molecular binding ability throughcooperative binding of one curcumin molecule in the closely located two cyclodextrin cavities, showing the enhanced bindingabilities of parent β-cyclodextrin by a factor 2.8 - 17.1. Conclusion Size/shape fit and hydrophobic interaction betweenhost cyclodextrins and guest curcumin molecule are the important factors affecting the binding ability and inclusion complexation behavior of these cyclodextrins 1 - 6.