Studies on the factors influencing Metformin Hydrochloride release from matrix tablets and the optimizition of formulation

Objective To prepare the metformin hydrochloride sustained-release tablets(MH-SRT) and study the influencing factors.Methods The metformin hydrochloride sustained-release tablets(MH-SRT) were prepared by HPMC as the matrix material.The effects of the viscosity of HPMC,sort of an adhensive,amount of a lubricant,and the preparation methods on the release of MH 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.Results The release behavior of the tablets follows the Higuchi equation.The viscosity of HPMC,the compression force has no significant effects on the release of MH-SRT,while the sort of an adhensive,amount of a lubricant and the preparation methods influcence the release of MH-SRT to some degree.The pH of the dissolving solution has significant effects.Conclusions Combining with other filers,a sustained release tablet (SRT) of once daily administration is prepared by using hydropropyl methylcellulose as the basic matrix material.