Preparation, Characterization and Release Kinetics of Encapsulated Lithium Carbonate into Carnauba Wax Microspheres

The objective of the present study was to minimise the unwanted side effects of lithium carbonate (LC) drug by kinetic control of drug release, LC was entrapped into gastro resistant, biodegradable carnauba wax microspheres using meltable emulsified dispersion cooling induced solidification technique utilizing a wetting agent. Solid, discrete, reproducible free flowing microspheres were prepared. The yield of the microspheres was up to 92.0%, having smooth surfaces, with free flowing and good packing properties, angle of repose, % Carr’s index and tapped density values were within the limit, more than 98.0% of the isolated spherical microspheres were in the particle size range of 345-365 μm were confirmed by scanning electron microscopy (SEM). The drug loaded in microspheres was stable and compatible, as confirmed by DSC and FTIR studies. The release of drug was controlled for more than 8 hours. Intestinal drug release from microspheres was studied and compared with the release behaviour of commercially available formulation Intalith CR -450. The release kinetics followed different transport mechanisms. The drug release performance was significantly affected by the materials used in microsphere preparations, which allows absorption in the intestinal tract.