Preparation and evaluation of sulindac alginate beads

Sulindac (SUL) is one of the potent nonsteroidal anti-​inflammatory drugs (NSAIDS) which has deleterious side effects on the gastrointestinal tract (GIT) such as irritation, ulceration and hemorrhage.  Calcium alginate beads loaded with sulindac were prepd. at 2:1 and 4:1 polymer to drug ratio.  The effect of polymer to drug ratio and the pH of the dissoln. medium (5.5 and 7.4) on the release profile of sulindac was investigated.  In all cases, the release rate mechanism followed Higuchi model with sustained release of sulindac from alginate beads.  The Higuchi model mechanism was confirmed by the linearization of the data when spherical matrix model was adopted.  As the polymer to drug ratio increased the amt. of drug released progressively decreased.  Also the release rate was significantly slower in the acidic side (pH 5.5) than that of pH 7.4.  The effect of the intact drug as well as sulindac alginate beads on the ulcerogenic activity of the drug in the stomach of rabbit was carried out.  The ulcerogenic activity of the intact drug disappeared and the mucosal surface was free of hemorrhage and inflammation when the drug is loaded with alginate beads.