Abstract

Sandhya Sharma*, Amarjeet Singh and Neelam Singh

ABSTRACT

The colon may be one of the finest sites for drug delivery because of the long residence time and the low digestive enzymatic activity; this may be useful for prolonged drug delivery. Also it is a prospective site for systemic delivery of therapeutic drugs. Mucoadhesive microspheres are comprehensively proved as a targeted drug delivery system for pharmaceutical appliances. To formulate and evaluate the colon targeted mucoadhesive microsphere of Aceclofenac. Formulation containing sodium alginate as a release retarding polymer and pectin as a mucoadhesive polymer prepared by ionotropic gelation method using calcium chloride as cross-linking agent. Mucoadhesive microsphere was enclosed in to hard gelatin capsule and capsule shell was coated with pH sensitive polymer to prevent the adherence of mucoadhesive microsphere in upper GIT. The microspheres were evaluated for physical characteristics such as surface morphology by scanning electron microscopy, drug entrapment efficiency, in vitro drug release and in vitro mucoadhesion. The optimized formulation was found on the basis of evaluation of mucoadhesive microspheres. Formulation (A30) showed the best result as drug entrapment efficiency 82.5%, in vitro drug release 98.7% and in vitro mucoadhesion 84%. Capsule was subjected to evaluate for in vitro drug release, disintegration time and drug release kinetic model was found as 96.43%, 2.41±1.16904 hr and first order model with R2 is0.951 respectively. The microspheres are found to have a good mucoadhesive property. Due to the mucoadhesive property of microsphere it was adhering to colonic mucosa for extended period of time and exerts local action in colonic mucosa. The outer enteric coating provided a satisfactory acid resistibility due to negligible release of drug in upper GIT. This proves the ability of the formulated capsule to sense the arrival of the dosage form to the colon where it gave the highest release. Thus it is signifying a promising sustained release drug delivery system.