Controlled Release of Drug to the Intestine from pH-responsive Chitosan-Poly (vinyl alcohol) Interpenetrating Network Hydrogels

Hydrogels are polymeric networks with three-dimensional configuration capable of imbibing high amounts of water or biological fluids. A truly amazing class of hydrogels that has found potential use for a wide variety of applications is the class of “smart” or “intelligent” hydrogels. Among all, pH-sensitive smart hydrogels have garnered special interest. Chitosan, a polycationic bioplomer, has received a great deal of attention in the fabrication of pH-responsive hydrogels. The interest in chitosan as intestinal drug delivery carriers arises from the fact that it is degraded by the microflora of the colon and is not digested in the upper gastrointestinal tract. Chitosan hydrogels, however, suffer from certain limitations such as poor mechanical strength, high porosity and tendency to absorb moisture. One of the most common methods to alleviate this problem is to incorporate chitosan into another polymeric network by the formation of an interpenetrating network. The focus of the present project is to synthesize pH-responsive chitosan- poly (vinyl alcohol) interpenetrating network hydrogels for controlled delivery of drug to the intestine