The present investigation is aimed to prepare the porous microspheres of carbamazepine using eudragit as release retardant, compritol as core forming agent, and HPMC as re-crystallization inhibitor for short-term sustained delivery of carbamazepine. The proposed microspheres were formulated using the emulsion solvent diffusion method. The obtained microspheres were characterized for its particle size distribution, thermal analysis (DSC), crystallinity (PXRD), surface morphology (SEM), and in vitro drug release. The prepared microspheres were found to be optimal in terms of particle size and entrapment efficacy. However, the obtained entrapment efficacy is insufficient to deliver the high dose drug such as carbamazepine. There were no compatibility issues and the drug is partially present in crystalline form in microspheres, which were confirmed by DSC and PXRD, respectively. The time to release 50% of drug from microspheres were in the range of 0.5 – 3.0 h, which could be used to prevent the formation of dihydrate and high extent of drug release. Further investigations are required to reduce the amount of polymer in microspheres that can provide maximum drug loading and acceptable dosage form.
Key words: Carbamazepine, microspheres, re-precipitation, sustained release, dissolution enhancement.
