Solubility of some inhaled glucocorticoids in supercritical carbon dioxide

The equilibrium solubilities of three glucocorticoid drugs were investigated at temperatures ranging from 338 to 358 K and pressures from 213 to 385 bar in supercritical CO2 by a simple and reliable static method. The crossover region was observed for beclomethasone dipropionate and budesonide at 243 bar. In case of fluticasone, at all conditions, the solubility was too low for correct determination. The solubilities of beclomethasone dipropionate and budesonide were correlated using a semi empirical model. Correlation of the results shows good self-consistency of the data obtained.