Alginate encapsulated bioadhesive chitosan microspheres for intestinal drug delivery.

Sustained intestinal delivery of drugs such as 5-fluorouracil (choice for colon carcinomas) and insulin (for diabetes mellitus) seems to be a feasible alternative to injection therapy. For successful therapy, the drug should be delivered at proper sites (here, the intestine) for long duration, for producing maximum pharmacological activity. We have attempted to develop a formulation that can bypass the acidity of the stomach and release the loaded drug for long periods into the intestine by using the bioadhesiveness of polyacrylic acid, alginate, and chitosan. Bromothymol blue was taken as a model drug. The formulation exhibited bioadhesive property and released the drug for an eight-day period in vitro.