Abstract

FORMULATION, OPTIMIZATION AND EVALUATION OF FLOATING PULSATILE BEADS OF CAPTOPRIL

Nimmi K. Thampi*, Boby Johns George, Daisy P. A. and Betty Carla

ABSTRACT

Background: The purpose of this work was to develop a dosage form of an antihypertensive drug for pulsatile release intended for chronotherapy of hypertension. Ionotropic gelation technique was used to develop calcium alginate beads. Methods: A 32 Full Factorial Design was employed to study the effect of independent variables (sodium alginate concentration, Sodium bicarbonate concentration) on dependent variables (Floating time, Percentage Cumulative drug release). Optimization was done by fitting the experimental data to software program (Design expert 10). Optimized beads were subjected to different evaluation parameters. Results: The optimized beads show good swelling in basic media compared to acidic media. The entrapment efficiency was 97.59%. The results of invitro drug release in both acidic and phosphate buffer showed minimum% cumulative drug release of 11.13% at 6th hr in acidic buffer and sudden release of 96.49% drug in phosphate buffer within 1 hr. Kinetics of the drug release study follows Higuchi and Kim Fassihi model. Conclusion: The optimized formulation can be used as pulsatile drug delivery system which provide time and site specific sudden drug release in intestine after a lag time of 6hrs in stomach which can be used to treat the morning surge in hypertension in patients with a night time dose itself.

Keywords: Chronotherapeutics; Pulsatile Drug Delivery System; Calcium alginate Bead; Captopril; Ionotropic gelation; 32 Full Factorial Design.