ABSTRACT
Objective To investigate effect of hydroxypropyl methyl cellulose (HPMC) to in vitro release characteristics of cefaclor sustained-release tablets.Methods Collected 10 batches of HPMC from different manufacturers.Determined the viscosity, molecular weight and the distribution of molecular weight of HPMC.HPMC from different manufacturers was used as blocking agent for the preparation of cefaclor sustained-release tablets according to the same prescription.Results The molecular weight was positively related to the viscosity of HPMC.The more molecular weight was, the slower the drugs release rate was,the better controlled released.Conclusion HPMC from different manufacturers show different quality stability and effect in vitro release of cefacor sustained-release tablets.