Host-guest complex of β-cyclodextrin and pluronic F127 with Luteolin: Physicochemical characterization, anti-oxidant activity and molecular modeling studies

The purpose of this investigation was to ameliorate the solubility and dissolution rate of luteolin (LUT) in aqueous phase by LUT: β-cyclodextrin (β CD) binary and LUT: β-cyclodextrin (β CD) : Pluronic F127 (PLF) ternary complex. Phase solubility study was performed with β CD as well as with β CD-PLF to assess the solubilizing efficiency. The solid complexes were prepared by solvent evaporation (SE), and microwave irradiation (MI) techniques. The in-vitro dissolution study was performed for the developed systems. The selected ternary complex was evaluated for solid state characterization, anti-oxidant effect and further molecular docking study was performed to provide structural insights and to identify the favorable role of β CD in improving the solubility of LUT. The key results of phase solubility studies indicated that 6.23 fold and 10 folds increase in LUT solubility with β CD and β CD-PLF respectively in comparison to pure LUT solubility. The formulation TIC-MI showed maximum drug release 97.06 ± 4.23% followed by TIC-SE (83.679 ± 3.78%) > BIC-MI (76.35 ± 3.57%) > BIC-SE (57.39 ± 2.11%) > TNPM (42.72 ± 2.45%) > BNPM (26.16 ± 1.71%). Most importantly IR, NMR study results revealed that there is no interaction was observed between LUT and used excipients. The antioxidant effect of the complex was found higher than that of LUT. The docking results demonstratethat LUT is completely embedded into the β CD cavity. Therefore, LUT: β CD: PLF ternary complex prepared by MI method found to be efficient with improved solubility, dissolution and antioxidant effect.