Formulation of Carbopol Capsules for Sustained Release of Losartan Potassium

  • Taha Umair Wani Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006
  • Nisar Ahmad Khan Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006


Sustained release formulations have been extensively studied for their benefits in improving various physicochemical and pharmacokinetic properties of large number of drugs. The aim of this study was to develop and evaluate sustained release capsules of losartan potassium in order to provide drug release over a long period of time. This allows the drug much time for absorption in gastrointestinal tract (GIT) and hence may increase the bioavailability of the drug. Carbopol 971 P was used as rate controlling polymer for the preparation of capsules. The capsules were evaluated for matrix integrity and drug release using USP type II dissolution apparatus. The sustained release capsules showed excellent matrix integrity and released more than 90% of the drug over a period of 12 hours. The kinetic studies showed that the drug release from the carbopol matrices followed Korsmeyer Peppas release kinetics and hence the mechanism of drug release was a combination of more than one processes i.e. diffusion and erossion. Hydration volume as well as matrix integrity were affected by the change in the amount of the polymer in the capsules. The study suggests that carbopol 971P capsules can be efficiently used to control and extend the release of losartan potassium over a long period. Thus improved absorption and bioavailability can be achieved which requires further studies in animals in future.

Keywords: Sustained release, Carbopol, Hydration volume, Capsules


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Author Biographies

Taha Umair Wani, Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006

Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006

Nisar Ahmad Khan, Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006

Department of Pharmaceutical Sciences, University of Kashmir, J&K Srinagar, 190006


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How to Cite
Wani TU, Khan NA. Formulation of Carbopol Capsules for Sustained Release of Losartan Potassium. JDDT [Internet]. 15Apr.2019 [cited 1Jun.2020];9(2-s):92-7. Available from: