A Comprehensive Review on Development and Investigational Strategies for Biphasic Site-Specific Floating Cum Bioadhesive Drug Delivery System
The purpose of this review is to compile the recent literature with special focus on characterization of both, in vitro and in vivo parameters for gastric behavior of biphasic floating cum bioadhesive site specific drug delivery system. This review consists of different types of bilayer floating drug delivery systems, one of the type, biphasic gastroretentive drug delivery system gives better patient compliance (by reducing both dose and dosing frequency) and increases the efficacy of drug therapy. Few drugs have narrow absorption window in GIT, so have poor absorption and there by leads to low bioavailability via conventional sustained release drug delivery system. Thus, few researchers have developed biphasic floating drug delivery system which becomes more promising approach in gastroretentive drug delivery system. It consists of immediate release layer to release the drug in a very short period for quick onset of action while another floating bioadhesive sustained release layer, to release the maintenance dose of drug with sustained fashion in stomach for desired period. We have focused on calculation of both doses such as loading and maintenance dose. Floating drug delivery systems are having bulk density less than gastric fluids therefore it remain buoyant in the stomach for a desired period of time, releasing the drug slowly but promptly at the desired rate from the systems. This review includes various sophisticated in vitro and modern in vivo evaluation techniques for biphasic floating bioadhesive site-specific drug delivery system including stability studies.