Bedaquiline fumarate microemulsion: formulation optimization, rheological characterization and in vitro studies - Supplementary data

Aim: Bedaquiline fumarate (BQF), an antitubercular drug, shows limited bioavailability due to solubilitylimited
intestinal absorption. In this research, the authors formulated a BQF-loaded microemulsion
to improve BQF’s oral bioavailability. Methods: Microemulsion was prepared by a spontaneous
emulsification method and evaluated for thermodynamic stability, size, dispersibility, transmittance,
rheology, microrheology, drug release, cytotoxicity and cellular uptake. Results: Microemulsion showed
an average globule size of 26.50 ± 6.29 nm with spherical geometry and revealed gel-sol-gel behavior
in microrheological studies. Cytotoxicity and cell uptake studies in Caco-2 cells showed that BQF
microemulsion was cytocompatible at the highest concentration of 500 μg/ml with significantly higher
cellular uptake than control. Conclusion: The present study indicates that BQF microemulsion could be
explored further for effective treatment of multidrug-resistant tuberculosis.