Preparation and in vitro release of metformin hydrochloride sustained release tablets

The paper discussed how to prepare metfoumin hydrochloride sustained release tablets(MH-SRT)and establish a detecting method of drug release.The tablets were prepared by using hydroxypropymethylcellose(HPMC)as the extended matrix material.The release rate of tablets was measured by UV.The effects of a filler and an adhesive on the release of metformin hydrochloride from matrix tablets were observed.On the basis of pharmaceutical preformulation studies,the preparation technique and optimized formulation of MH-SRT were determined by the orthogonal design test according to cumulative percent of drug release.Three batch of sustained release tablets were prepared according to the optimized formulation.In vitro releasing properties of the sustained release tablets were compared with normal metformin hydrochloride tablets.The release behavior of the tablets follows the Higuchi equation within 12 hours.