GASTRORETANTIVE SYSTEM OF ATENOLOL USING HPMC K15

ABSTRACT: Floating matrix tablets of atenolol were prepared to provide sustained drug delivery of atenolol and also to enhance the bioavailability of the drug. Atenolol was chosen as a model drug because it is better absorbed form stomach than the intestine. Tablets were prepared using direct compression technique using HPMC K15, chitosan and carbopol 934P. Drug and polymers were evaluated for compatibility study using differential scanning calorimetry (DSC). Prepared tablets were evaluated for physical parameters viz. hardness, swelling index, thickness, weight variation, buoyancy time. All the tablets were evaluated for in vitro release study using pH 1.2 hydrochloric acid buffer as dissolution medium. To analyze the mechanism of drug release from the tablets, the in vitro dissolution datas were fitted to zero order, first order, higuchi release model and korsmeyer and peppas model. All the tablets were showing buoyancy time of 24 hr. The results indicated the release of atenolol from the tablets was in controlled fashion. It was observed that the release of drug followed zero order release and controlled by both diffusion and erosion mechanism. The effervescent based floating drug delivery was a promising approach to achieve in vitro buoyancy. The addition of gas generating agent sodium bicarbonate was essential to achieve in vitro buoyancy. The drug release from the tablets depends upon the nature of gel matrix. It may thus conclude that polymer swelling play an important role in pattern and amount of drug release from the formulation