Fabrication of sulfobutylether-β-cyclodextrin/glabridin inclusion complex for promoting bioactivities

As the main active compound of Glycyrrhiza glabra L., glabridin (GLD) has been shown to have multiple bioactivities, whereas the clinical application of GLD is restricted by its low water solubility. In this study, GLD was encapsulated into a sulfobutylether-β-cyclodextrin (SBE-β-CD)-based inclusion complex (SBE-β-CD/GLD) by the freeze-drying method. The materials characterization, antibacterial activity, stimulated cellular behavior and in vivo full-thickness diabetic wound healing ability of the hydrogels were assessed and analyzed. The successful encapsulation of the inclusion complex was confirmed by ultraviolet (UV) visible spectroscopy, Fourier transform infrared (FT-IR), X-ray diffractometer (XRD), scanning electron microscope (SEM), and nuclear magnetic resonance (NMR). SBE-β-CD as an excipient significantly enhances the water solubility of GLD, and SBE-β-CD/GLD showed excellent biocompatibility on human vascular endothelial cells (HUVECs) and erythrocytes. The SBE-β-CD/GLD inclusion complex exerted a pronounced antibacterial activity on Staphylococcus aureus and Escherichia coli in vitro. The SBE-β-CD/GLD inclusion complex markedly enhanced the antioxidant activity compared with free GLD. The SBE-β-CD/GLD inclusion complex potently accelerates the healing of full-thickness skin defects by inhibiting inflammation. The outcomes suggest that SBE-β-CD could be used as a promising drug delivery system for the clinical application of GLD.