In vitro Release Kinetic Study of Esomeprazole Magnesium from Methocel K15M and Methocel K100 LVCR Matrix Tablets

Abstract

In the present study esomeprazole sustained release tablet matrix was prepared by utilizing different
grades of hydroxypropyl methylcellulose (HPMC) polymers such as Methocel K15M & Methocel K100 LVCR by
direct compression method. Different amount of Methocel K15M was used to develop matrix builder in the seven
proposed formulations (F1-F7) for the study of release rate retardant effect at 20%, 25%, 30%, 35%, 40%, 45% and
50% of total weight of tablet matrix respectively. The dissolution study of Methocel K15M based tablet matrices of
those proposed formulations were carried out in the simulated gastric medium (pH 1.3) for first two hours and then in
the simulated intestinal medium (pH 6.8) for 8 hours using USP dissolution apparatus II. The formulation F-5 (40%)
and F-6 (45%) met the optimum release rate of esomeprazole for 10h period of in vitro dissolution study. The release
kinetics of formulation F-5 and F-6 very closely followed Higuchi kinetic order than first order and zero order
kinetics. Similarly Methocel K100 LVCR was used to develop matrix builder in another seven proposed formulations
(F8-F14). It was found that formulations F-11 (35%), F-12 (40%) and F-13 (45%) met the desired release rate of
esomeprazole for 10h period. The release kinetics of formulation F-11, F-12 and F-13 followed Higuchi kinetic order.
Between these two polymers, Methocel K100 LVCR showed better release retardant effect than Methocel K15M.