IN VITRO RELEASE KINETICS STUDY OF TRAMADOL HCl SUSTAINED RELEASE MATRIX TABLET FROM HPMC

In the present study, an effort has been made to evaluate of hydroxypropyl methylcellulose HPMC K15M as rate retardant polymer to sustain the release of Tramadol HCl from Tramadol HCl sustained release tablet matrix. Different amount of HPMC K15M were used in formulation of F1 to F5 where drug and polymer ratio were consequently 5:6, 5:5, 5:4, 5:3 and 5:2 in 200 mg tablet matrix. Tablets were prepared by direct compression. The dissolution study of the tablet matrices of different formulations were carried out in the gastric medium (pH 1.3) for first 2 hours and then in the intestinal medium (pH 6.8) for 6 hours using USP dissolution apparatus II. The drug release patterns were simulated in different kinetic orders such as Zero Order release kinetics, First Order release kinetics, Higuchi release kinetics, Korsemeyer-Peppas release kinetics and Hixson-Crowell release kinetics to assess the release mechanism. From the study it was observed that Zero Order release kinetics was the predominant release mechanism than Higuch