Enhancement of oral bioavailability of magnolol by encapsulation in mixed micelles containing pluronic F127 and L61

OBJECTIVES: We aimed to prepare novel magnolol-loaded mixed micelles (MAG-M) by pluronic F127 and L61 to overcome the challenges of magnolol's poor solubility and then further improve its oral bioavailability. METHODS: Magnolol-loaded mixed micelles containing pluronic F127 and L61 were prepared by an organic solvent evaporation method. Physicochemical, transport experiment across Caco-2 cell monolayers and pharmacokinetic studies were performed to characterize MAG-M and to determine the final improvement of the oral bioavailability. KEY FINDINGS: The MAG-M solution was transparent and colourless with average size, polydispersity index and zeta potential of 228.0 ± 2.1 nm, 0.298 ± 0.012 and -0.89 ± 0.02 mV. The micelle solution has a higher EE% and DL% of 81.57 ± 1.49% and 27.58 ± 0.53%, respectively. TEM result showed that the morphology of MAG-M was homogeneous and spherical shape. The dilution stability of MAG-M was no significant change in particle size and entrapment efficiency. MAG was demonstrated a sustained-release behaviour after encapsulated in micelles. MAG permeability across a Caco-2 cell monolayer was enhanced, and the pharmacokinetics study of MAG-M showed a 2.83-fold increase in relative oral bioavailability compared with raw MAG. CONCLUSIONS: The mixed micelles containing pluronic F127 and L61 as drug delivery system provided a well strategy for resolving the poor solubility and bioavailability problems of MAG.