EFFECT OF SINTERING CONDITION ON PHYSIO-CHEMICAL PARAMETERS AND DRUG RELEASE CHARACTERISTICS FROM POLYMERIC MATRIX TABLET OF ATENOLOL FOR CONTROLLED RELEASE

Sintering technique, a relatively new, convenient, economic process for making polymeric matrices for controlled release is described here. The objective of the present investigation was to prepare thermally sintered matrix tablets of Atenolol using Eudragit RS 100 as sintering polymer and to study the effect of thermal treatment on drug release; physiochemical properties of the prepared tablets. The tablets are prepared by direct compression method. The compressed fluffy matrices were subjected to thermal treatment at three different constant temperatures like 60 °C, 70°C and 80°C for two different periods like 1.5 hr and 3 hr in hot air oven. The sintering condition markedly affected the drug release characteristics of prepared matrix tablets. Drug release rate was found to be inversely related with the sintering temperature and sintering duration. Hardness of tablets was found to be increased with increasing sintering time and temperature; whereas friability was decreased with sintering. Both percent water uptake and percent erosion of sintered tablets decreased with increase in sintering condition. Based on the evaluation tests with mentioned parameters, formulation F2 Sintered at 80 °C for 3 hr was selected as optimised formulation. The drug release kinetics from formulations was best described by the Higuchi model and it followed anomalous non-Fickian diffusion mechanism. SEM analysis conformed smoother tablet surface and decrease in the porosity of sintered tablet. FTIR and DSC studies revealed that there was no evidence of interaction between the drug and polymer used in the study and no polymorphic changes in drug due to thermal sintering.