Formulation of amorphous ternary solid dispersions of dapagliflozin using PEG 6000 and Poloxamer 188: solid-state characterization, ex vivo study, and molecular simulation assessment

The present study was designed to prepare dapagliflozin (DFG) loaded ternary solid dispersions (SDs) using the carrier blend polyethylene glycol 6000 (PEG 6000) and poloxamer 188 (PLX 188). The prepared DFG-SDs were evaluated for solubility study, physicochemical characterization and molecular simulation study. The prepared DFG-SDs showed significant higher solubility and dissolution vis-a-vis pure DFG and DFG physical mixture. The composition DFG:PEG:PLX (1:2.25:0.75 mM) showed the highest solubility (0.476 ± 0.016 mg/mL). The physicochemical characterization confirms the polymorphic transition of DFG from crystalline state to stable amorphous form. The prepared DFG-SDs showed a significantly higher dissolution (64.78 ± 2.34% to 78.41 ± 2.39%) than pure DFG (15.70 ± 3.54%). DFG-SD2 showed a significantly enhanced drug permeation (p<.05) (58.76 ± 4.65 µg/cm) as compared to pure DFG (14.97 ± 3.32 µg/cm). The molecular docking study result revealed a good hydrophobic interaction of DFG with the used carrier due to the lowest energy pose. The interaction occurs between the methylene bridges and the central hydrophobic chain of polyoxypropylene of the polymer. Therefore, DFG-SDs prepared by microwave irradiation method using hydrophilic carrier blend might be a promising strategy for improving the solubility and in vitro dissolution performance.