Synthesis and Controlled Release Properties of Prednisone Intercalated Mg−Al Layered Double Hydroxide Composite

A drug−inorganic composite involving prednisone−cholate ion micelles intercalated Mg−Al layered double hydroxide (LDH) has been assembled by a coprecipitation method. Powder X-ray diffraction (XRD), Fourier transform infrared (FT-IR), and UV−vis absorption spectroscopy indicate a successful intercalation of prednisone-containing micelles into galleries of the LDH matrix. The in vitro drug release studies show that no burst release phenomenon was observed at the beginning of release tests, and the pH value imposes very little influence on the release performance of prednisone in the studied pH range 4.8−7.6. It is, therefore, concluded that the MgAl-LDH can be used as an excellent inorganic drug carrier for prednisone in a wide range of pH values. Four kinetic models (first-order equation, Higuchi equation, Bhaskas equation, and Ritger−Peppas equation) were chosen to study the release kinetics of prednisone from the LDH carrier, and it was found that this process can be described by the Ritger−Peppas equation satisfactorily based on a directing Excel-based solver (DEBS). Moreover, the mechanism for drug release was also discussed.