Dissolution Behavior of Oxazepam in Presence of Cyclodextrins: Evaluation of Oxazepam-Dimeb Binary Systemxs

The inclusion complex formation between oxazepam (Ox) and heptakis (2,6-di-O-methyl)-β-cyclodextrin (DIMEB) was studied in solution by solubility and ultraviolet spectroscopy methods, and in the solid state by differential scanning calorimetry, scanning electron microscopy, and powder x-ray diffractometry. The apparent stability constant, K_c, calculated by solubility and spectral data, was estimated as 642 and 588 M^-1, respectively. The solid complexes have been prepared by kneading and spray-drying techniques. The dissolution rate studies reveal that the better dissolution behavior corresponded to the spray-dried systems.