Preparation and characterisation of ecdysterone/hydroxypropyl-Β-cyclodextrin inclusion complex with enhanced oral and transdermal bioavailability

Abstract

To prepare ecdysterone (ES)/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex, thus improving the water solubility and bioavailability of ES. Phase-solubility study was performed to study the mass ratio of ES and HP-β-CD. Then, the ES/HP-β-CD inclusion complex was prepared by the solvent evaporation method, and its physicochemical properties were characterised using the SEM, DSC, XRD, ¹HNMR and FT-IR. In addition, in vitro dissolution and bioavailability (oral and transdermal) experiments were also conducted. The inclusion complex was formed with ES and HP-β-CD at the mass ratio of 1:1. ES existed in an amorphous form in the inclusion complex. The equilibrium solubility of ES/HP-β-CD inclusion complex in SGF (simulated gastric fluid) and SIF (simulated intestinal fluid) was 50.6 ± 0.11 mg/mL and 75.9 ± 0.38 mg/mL in SGF and SIF, which was 5.93 and 9.96 times higher than that of free ES, respectively. The ES/HP-β-CD inclusion complex had better dissolution ability and transdermal permeability than the free ES. The oral bioavailability and the transdermal bioavailability were respectively increased by 2.97 times and 1.92 times compared with the free ES. These data suggest that the ES/HP-β-CD inclusion complex can be developed as potential pharmaceutical product for future clinical applications.

Keywords:

• Ecdysterone
• HP-β-CD
• inclusion complex
• bioavailability

Ethics approval and consent to participate

All animals were housed and treated according to the Guidelines for Care and Use of Laboratory Animals of Harbin Medical University and approved by the Ethics Committee of the Harbin Medical University (May 20th, 2019, no. 2019052003).

Acknowledgements

The authors are grateful for the precious comments and careful corrections made by anonymous reviewers.

Author contributions

Experimental design: Xiuhua Zhao; experimental operation: Li Wang, Hongda Cai, Xiaohu Liu, Tongtong Feng; data analysis: Li Wang, Shen Li; drafting manuscript: Li Wang, Hongda Cai; all the authors read and approved the final manuscript.

Disclosure statement

No potential conflict of interest was reported by the author(s).

Data availability statement

All data generated and analysed during this study are included in this article.

Additional information

Funding

This work was supported by the financial support from the Fundamental Research Funds for the Central Universities [no. 2572019AA18], the Excellent Youth Foundation of Heilongjiang Scientific Committee [no. JC2018005] and Heilongjiang Touyan Innovation Team Program (Tree Genetics and Breeding Innovation Team), the 111 Project [B20088].