Natural gums as sustained release carriers: development of gastroretentive drug delivery system of ziprasidone HCl

Formulation chiefly contains locust bean gum found to be favorable for hardness and floatability but combined effect of three variables was responsible for the sustained release of drug. The in vitro drug release data of check point batch (F8) was found to be sustained well compared to the most satisfactory formulation (F7) of 7 runs. The ‘n’ value was found to be between 0.5 and 1 suggesting that release of drug follows anomalous (non-fickian) diffusion mechanism indicating both diffusion and erosion mechanism from these natural gums. Predicted results were almost similar to the observed experimental values indicating the accuracy of the design. In vivo floatability test indicated non adherence to the gastric mucosa and tablets remain buoyant for more than 24 h.Study showed these eco-friendly natural gums can be considered as promising SR polymers.The use of naturally occurring hydrophilic biocompatible polymeric materials has been focused in recent research activity in the design of oral controlled release dosage forms [1]. Natural gums are among the most popular hydrophilic polymers because of their cost-effectiveness and regulatory acceptance [2,3]. The use of naturally occurring plant-based pharmaceutical excipients has become very important in the development of controlled release dosage forms, because of their ability to produce a wide range of material based on their properties and molecular weight [4]. Plant based materials can be modified to meet the requirements of drug delivery systems and thus can compete with the synthetic excipients available in the market [5].Okra gum and locust bean gum are water soluble thickening agents which have not been much studied for their pharmaceutical applications [6]. Okra gum, obtained from the fruits of Hibiscus esculentus L. (Moench), Malvaceae, is a polysaccharide consisting of D-galactose, L-rhamnose and L-galacturonic acid [7]. Locust bean gum (LBG) is a neutral plant galactomannan extracted from the seed (kernels)