Abstract
The aim of this study is to review the advantage of Mucoadhesive microsphere, mechanism and theories involved in mucoadhesion, factor that affect the mucoadhesion and polymers in the drug delivery systems. Gastroretentive systems are those which are retained in the stomach for a longer period of time and thereby improve the bioavailability of drugs. Also to evaluate the potential use of mucoadhesive microspheres for Gastroretentive delivery.Chitosan, thiolated chitosan, Carbopol 71G and Methocel K15M were used as mucoadhesive polymers. The poor bioavailability of microsphere is attributed to short retention of its dosage form at the absorption sites (in upper gastrointestinal tract to duodenum and jejunum). Overall review indicated prolonged delivery with significant improvement in oral bioavailability of mucoadhesive microspheres due to enhanced retention in the upper GI tract.Gastric emptying is a complex process and makes in vivo performance of the drug delivery systems uncertain. In order to avoid this variability, efforts have been made to increase the retention time of the drug-delivery systems for more than 12 hours.. The present review addresses briefly about the floating drug delivery systems. Uniformly sized polymeric microspheres that support a variety of applications in the life sciences. Available in diameters ranging from 20nm to 20μm, products exhibit excellent size uniformity. Most of our microspheres are polystyrene-based, although some other base polymers are also offered. Plain (non-functionalized) polymer microspheres are ideal for protein adsorption applications, while surface modified microspheres (COOH or NH2) are used for covalent ligand attachment. Cross-linked polymer microspheres are available for improved solvent, heat, and pressure resistance. Polymer microspheres are also available with impregnated visible or fluorescent dyes.
