大豆苷元与氨基修饰β-环糊精包合物的制备、表征及水溶性

摘要

To improve the water solubility of daidzein, solid inclusion complexes of daidzein with two amino-modified β-cyclodextrins (ACDs), i.e., mono-6-amino-6-deoxy-β-cyclodextrin (NCD) and mono-6-ethylenediamino-6-deoxy-β-cyclodextrin (ENCD), were prepared by the saturated solution method in water under the preparation conditions as follows: the ratio of daidzein/ACD was 3∶1 and the stirring time was 72 h (83% and 67% yields, respectively).The formation of two inclusion complexes was confirmed by x-ray diffractometry (XRD) and themogravimetric (TG) analysis.The inclusion stoichiometry of the inclusion complexes was 1∶1 from the Job plot and their complexation stability constants (KS) were 899.2 and 203.8 L/mol from fluorescence titration, respectively.After formation of inclusion complexes with NCD and ENCD, the water solubility of daidzein was dramatically raised from 8.31 μg/mL to 15.2 and 13.2 mg/mL at 25℃, increasing by 1800-fold and 1500-fold.%采用饱和水溶液法制备了大豆苷元分别与两种氨基修饰β-环糊精(ACD) 即单-6-氨基-β-环糊精(NCD) 和单-6-乙二胺基-β-环糊精(ENCD) 的固体包合物,并获得最佳包合条件:大豆苷元与环糊精投料比为3∶1(n/n) ,搅拌时间为72 h,分别获得83%和67%的产率.利用X-射线粉末衍射和热重分析对其进行了表征,证实了两种包合物的形成.利用Job′s曲线法确定了主客体的包合比为1∶1,并利用荧光光谱滴定分析测得其包合稳定常数KS分别为899.2和203.8 L/mol.水溶性实验表明,通过与NCD和ENCD形成包合物,25℃下大豆苷元在水中的溶解度由原来的8.31 μg/mL增至15.2和13.2 mg/mL,分别提高了约1800和1500倍.