Release behaviour of drugs from tamarind seed polysaccharide tablets.

PURPOSE: This study examines the sustained release behaviour of both water-soluble (acetaminophen, caffeine, theophylline and salicylic acid) and water insoluble (indomethacin) drugs from tamarind seed polysaccharide isolated from tamarind kernel powder. It further investigates the effect of incorporation of diluents like microcrystalline cellulose and lactose on release of caffeine and partial cross-linking of the polysaccharide on release of acetaminophen. Applying exponential equation, the mechanism of release of soluble drugs was found to be anomalous. The insoluble drug showed near case II or zero order release mechanism. The rate of release was in the decreasing order of caffeine, acetaminophen, theophylline, salicylic acid and indomethacin. An increase in release kinetics of drug was observed on blending with diluents. However, the rate of release varied with type and amount of blend in the matrix. The mechanism of release due to effect of diluents was found to be anomalous. The rate of release of drug decreased on partial cross-linking and the mechanism of release was found to be super case II.