Ionotropic Gelation: A Promising Cross Linking Technique for Hydrogels.

Microencapsulation is by far the most commonly exploited technique for the generation of multipartuculate drug delivery system. But serious drawbacks of this technique like non-uniform coating, non-reproducible release kinetics and more importantly, the use of more or less harsh conditions in the formulation process limits the encapsulation of the many substances such as proteins, enzymes and live cells etc. Besides this, the regulatory authorities, such as U.S.FDA are restricting to greater degrees the amount of additional components allowed such as organic solvents. The solution of this problem is presented by a technique, which involved neither the use of harsh chemicals nor elevated temperature and based on principle of ionotropic gelation (polyelectrolyte complexation). This review emphasizes the importance of ionotropic gelation and its cross linking potential to formulate hydrogel beads using different natural polymers.