Nifedipine is one of the calcium channel blockers widely employed in indications such as high blood pressure and angina pectoris. In the present study, a prompt attempt is done in the formulation of gastro retentive sustained-release tablets. The effect of polymers and their combination on release pattern, initial burst release, and floating behavior were studied. Out of four polymers, two polymers such as cellulose derivatives like highly viscous polymer Hydroxypropyl methylcellulose (HPMC) K100, low viscous HPMC K4M and their combinations, and other two polymers used were from natural sources like xantham gum, guar gum and their combinations were studied. The percentage of drug release was compared with the theoretical model. Formulated gastro retentive Nifedipine floating tablets were evaluated with various parameters such as wetting time, floating behavior, hardness test, swelling studies, and drug release. The combinations of natural polymers had shown the best result on drug release and initial burst release such as 98.28 and 22%, respectively, with floating lag time of 90 s. Dissolution data were fitted into various mathematical equations like zero-order, First order, Hixon Crowell, and Higuchi model to understand the concept of drug release. Based on result, it was found that optimized formulation follows the Hixon Crowell equation (r2 > 0.966) and zero-order drug release (r2 > 0.968). The conclusion is that gastroretentive Nifedipine floating tablets followed dissolution controlled mechanism of drug release. The similarity factor f2 and dissimilarity factor f1 were found to be 76.02 and 4.32, respectively, for Nifedipine release from the optimized batch in comparison with the theoretical drug release profile. Short term accelerated stability studies were conducted as per ICH guidelines and evaluated.
Faculty of Pharmaceutical Sciences, Chulalongkorn University
Pradeep, H. K.; Thimmasetty, Juturu; Babu, P.R. Sathesh; Gururaj, S.; and Sreeharsha, N.
"Behavior of polymers and in-vitro evaluation on gastroretentive nifedipine sustained release floating tablets,"
The Thai Journal of Pharmaceutical Sciences: Vol. 46:
1, Article 8.
Available at: https://digital.car.chula.ac.th/tjps/vol46/iss1/8