Design of Floating Drug Delivery Systems: An Update on Polymeric Advancements with Special Reference from Natural Origin

摘要

The purpose of writing this review on design of floating drug delivery systems is to give an update on polymeric advancements to compile the recent literatures with special focus on the polymers used in floating drug delivery systems mostly from natural origin. Floating drug delivery systems are less dense than gastric fluids; hence remain buoyant in the upper gastrointestinal tract for a prolonged period, releasing the drug at the desired rate. Thus enhances the bioavailability of certain drugs having absorption window nearer to upper gastrointestinal tract. This review article focuses on: the recent technological development in floating drug delivery systems with special emphasis on the principal mechanism of floatation and advantages of achieving gastric retention and its potential for oral controlled drug delivery; polymers used in both single unit and multiunit floating systems; brief collection on various natural polymers employed for floating drug delivery systems etc. Although a variety of polymeric materials are available to serve as release retarding floating matrices but use of natural polymers to prolong the delivery of the drugs is always an area of active research despite the advent of synthetic biodegradable polymers. Natural polymers remains attractive primarily because they are readily available in the nature, relatively inexpensive, products of living organisms, readily undergoes in-vivo degradation, non- toxic and capable of chemical modifications .