Astragaloside-Soluplus/TPGS/glycyrrhizic acid ammonium salt mixed micelles: preparation and pharmacodynamic evaluation

Astragaloside, a natural flavonol glycoside isolated from plants, exhibits significant tumour-suppressive activity. However, its low solubility and poor bioavailability have hindered its practical application. To improve its bioavailability and therapeutic efficacy, this study prepared Ast-loaded Soluplus/TPGS/Gas hybrid polymer micelles (Ast-STG-M) via the thin-film hydration method. The resulting Ast-STG-M nanoparticles were spherical and uniformly dispersed, characterised by a small particle size (50.92 ± 0.13 nm) and a high encapsulation efficiency (95.24 ± 0.53%). In vitro release profiles demonstrated that the cumulative release rate of Ast from Ast-STG-M was higher than that of free Ast under various pH conditions. After oral administration, compared with free Ast, Ast-STG-M exhibited delayed in vivo elimination and significantly increased bioavailability. Furthermore, results from in vitro and in vivo anti-tumour studies indicated that Ast-STG-M could significantly inhibit the viability of TPC-1 cells, thereby effectively suppressing the growth of solid tumours. In conclusion, Ast-STG-M holds substantial potential as a delivery system for Ast to tumour sites, which not only enhances the oral bioavailability of Ast but also strengthens its anti-cancer activity.