ABSTRACT:
The aim of this study is to review the gatro-retentive muco-adhesive microspheres, basic anatomy of stomach and its physiology, introduction of gastro-retentive drug delivery system, muco-adhesive (bio-adhesive) systems, mechanism of muco-adhesion, methods of preparation of muco-adhesive microspheres and evaluation of controlled release muco-adhesive microspheres. Gatro-retentive drug delivery system which remains in stomach for long duration of time, during which drug release in controlled manner. Muco-adhesion is one of the approaches of gastric retention by attaching to mucin in stomach to enhance residence time. For muco- adhesion different polymer (s) may used. Muco-adhestive microspheres have most of advantage for patient compliance as it is multi unit particle drug delivery system. Muco- adhesive microspheres may prepared by different method such as Complex Coacervation , Hot Melt Micro-Encapsulation , Emulsification- Internal Gelation Technique , Double Emulsion Method , Solvent Removal , Iono-Tropic Gelation , Phase Inversion Method and Spray Drying . Gastro-retentive muco- adhesive microspheres evaluated for percentage yield, particle size determination, determination of particle size distribution and zeta potential, micromeritic studies, drug entrapment efficiency, scanning electron microscopy, Muco-adhesive property of microspheres, in vitro drug release study, kinetics of drug release, and stability studies.