Inhalable curcumin formulations: Micronization and bioassay

Inhalable formulations of curcumin with hydroxypropyl-β-cyclodextrin and polyvinylpyrrolidone have been produced by a newly developed anti-solvent micronization technique based on the supercritical fluid (SCF) technology. The micronization process used is the atomized rapid injection solvent extraction process (ARISE), which utilizes high pressure carbon dioxide as the anti-solvent. The composition, particle morphology and aerodynamic performance of the samples were observed. Curcumin formulations with aerodynamic performance suitable for inhalation delivery have been produced and tested in vitro using normal and lung cancer cells (MRC-5 cells and H1299 cells, respectively). The cytotoxicity study revealed that the encapsulation of curcumin improved its biodistribution and solubility for lung cancer cells. A rapid cell uptake was observed for all formulations by confocal microscopy and flow cytometry. Fluorescence life time imaging microscopy showed a rapid release of curcumin in the cells. Results show that co-processing by ARISE preserved the anticancer properties of curcumin and generated inhalable powders thus demonstrating potential in the localized treatment of lung cancer.