ABSTRACT
Polar functional groups in natural polysaccharides come with a high molecular weight and a relatively rigid backbone. If the drugs have a high pH level or are easily degraded by enzymatic action they also need a special carrier system for intestinal delivery. Polysaccharides are complex carbohydrates with long chains of monosaccharide units bound together by glyosidic linkages. Natural polysaccharides are stable to a high temp. They also offer high melting and softening temperatures and high cohesive forces of interaction. Natural polysaccharide grafting is a method where monomers of other polymers are covalently bonded onto the existing polymer chain. It improves the structure-function relationship of natural polysaccharides by imparting a variety of functional groups onto the backbone. The concept of grafting allows structural modification on the primary polymer backbone. The modification of the natural biopolymer requires a specific drug or group of drugs for particular delivery requirements.
