β-环糊精与土霉素的相互作用研究及分析应用

Study and application on the inclusion complexation of β-cyclodextrin and oxytetracycline

以荧光法研究了土霉素（OTC）与环糊精（β-CD）的包合作用,并利用β-CD对OTC荧光的增敏作用建立了一种高灵敏度测定OTC的新方法,土霉素在9.19×10^-8-1.66×10^-5mol/L范围内与荧光强度成正比,方法的检出限为7.4×10^-9mol/L,方法用于药物制剂中土霉素的测定,结果与标示量吻合。荧光光度法测得OTC与β-CD形成1∶1包合物,包合物形成常数为3.68×10^2L/mol。从土霉素和环糊精的分子结构出发,对包合物的形成机理进行了探讨。

The interaction of oxytetracycline with β-cyclodextrin has been studied by fluorescence spectrometry. It was found that the fluorescence intensity of OTC was greatly enhanced in the presence of β-CD. A new fluorescence method was established for the determination of OTC with high selectivity and specificity. The fluorescence intensity was linearly related to the OTC concentration in the range of 9.19 ×10^-8- - 1.66 × 10^-5 mol/L and the detection limit was 7.4 × 10^-9 mol/L. The method was satisfactorily applied to the determination of OTC in pharmaceutical preparations. The results show that OTC has formed a 1 ： 1 inclusion complex with β-CD, and their formation constant was 3.68 ×10^2 L/mol. Their possible inclusion mechanism has been discussed.