Synthesis and Characterization of Water Soluble Diethylenetriamine‐β‐Cyclodextrin/Ethinylestradiol Inclusion Complex

Abstract Ethinylestradiol (EE), is widely used to treat conditions such as breast cancer, prostate cancer and climacteric syndrome. However, due to the low water solubility of EE, the bioavailability of EE is low. Herein, to improve the bioavailability of EE, a hydrosoluble cyclodextrin drug carrier system, diethylenetriamine‐β‐cyclodextrin/ethinylestradiol (DETA‐β‐CD/EE) was prepared. High performance liquid chromatography (HPLC), fourier transform infrared (FTIR), 2D rotating frame overhauser effect spectroscopy (ROESY) spectrum and scanning electron microscope (SEM) were used to characterize the DETA‐β‐CD/EE. HPLC test showed that DETA‐β‐CD was the optimal host molecule, which can improve the solubility of EE to 496 mg L −1 . Phase solubility indicated the formation of a soluble inclusion complex with 1 : 1 stoichiometry. In terms of practical application, the solubility and stability of DETA‐β‐CD/EE in blood was proved by dissolution rate studies. Overall, by the encapsulation in polysaccharide DETA‐β‐CD, the water solubility of EE is increased by 100 times. The establishment of hydrosoluble cyclodextrin drug carrier system provides support for the sustained release system or large dose drug delivery.