ABSTRACT
In this study, butaselen-2,6-dimethyl-β-cyclodextrin inclusion complexes were prepared by saturated aqueous solution method to improve the solubility of butaselen, so as to obtain its injection solutions. The content of butaselen in the inclusions was determined by high performance liquid chromatography (HPLC), and then the preparation process was optimized by orthogonal design using the inclusion ratio as an indicator. X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR) and scanning electron microscope (SEM) were used to verify the structure of the inclusions. The effects of the inclusions on the solubility and stability of butaselen were also investigated. The results showed that the optimized preparation process with a mass ratio of 1∶340, an encapsulation time of 3 h and an encapsulation temperature of 70 ℃ resulted in an encapsulation ratio of (91.24 ± 0.42) %, and the results of XRD, FTIR and SEM demonstrated the formation of inclusion complexes. The developed HPLC method is rapid, simple, accurate, applicable, specific and reproducible for the determination of butaselen content in butaselen cyclodextrin inclusion complexes, which can lay the foundation for the development of new butaselen dosage forms and clinical applications and provide technical support.
ABSTRACT
Objective: To prepare tetrahydropalmatine (THP) and β-cyclodextrin (β-CD) and its derivatives inclusion complexes (HP-β-CD, DM-β-CD, and TM-β-CD and explore their inclusion behavior and properties. Methods: The inclusion complexes of THP with β-CD, HP-β-CD, DM-β-CD, and TM-β-CD were prepared by saturated solution. The inclusion ratio and stability constant of inclusion complexes were determined with the Job plot and UV-vis spectroscopy. The THP/CDs complexes were characterized and determinated by means of XRD, TG, and SEM. The molecular simulation was processed to investigate the inclusion behavior of THP and different CDs. The water solubility of the inclusion complexes was measured and the stability test was conducted in the simulated human gastric juice and intestinal fluid environment. Results: Job plot and UV-vis spectroscopy showed that inclusion ratio of host-guest inclusion complexes was 1:1. Molecular docking showed that the entire THP entered the macrophage port and run through the cavities of β-CD and DM-β-CD, with the two aromatic rings located at the large and small mouth, respectively. For HP-β-CD and TM-β-CD, the two nitrogen heterocycle of THP were “V” shaped inlaid into the CD cavity, and both aromatic rings were located at the large end of the CDs. Conclusion: The solubility of tetrahydropalmatine was increased from 0.30 mg/mL to 1.60, 3.40, 9.13, and 4.02 mg/mL for β-CD, HP-β-CD, DM-β-CD, and TM-β-CD, respectively. The thermal stability and biological environment stability had been significantly improved.