ABSTRACT
OBJECTIVE: To determine the constant for the inclusion complex of Yinqiao volatile oil with beta-cyclodextrin. METHOD: The stability constant for the inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was detemined under multiwavelength by ultraviolet spectroscopy, and spectroscopy feature for inclusion complex was studied. The phase solubility-curve showed the inclusion proportion. The inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was prepared by saturated aqueous solution. The DTA spectroscopy of inclusion complex was different from not only oil with beta-cyclodextrin but also the mixture of them. RESULT: The inclusion complex of Yinqiao the volatile oil with beta-cyclodextrin was formed. The experimental data of inclusion complex fitted well to the molar ratio of 1:1. There was good liner feature under multiwavelength of ultraviolet spectroscopy. CONCLUSION: Adopting multiwavelength method may determine the appearant stability constant of multicomponential traditional drug. The determination of the stability constant of the inclusion complex can be used in traditional drug.