Grafting of Natural Polymers and Gums for Drug Delivery Applications: A Perspective Review

Natural polymers have received more attention because of their advantages over synthetic polymers such as abundant availability, low cost, biodegradability and non-toxicity. However, natural polymers suffer some limitations such as drop-in viscosity upon storage, uncontrolled hydration, solubility, inability to perform under high temperature and pressure (thermal stability), etc. In many instances above mentioned drawbacks of natural polymers limits their applications in drug delivery systems. Grafting of natural polymer leads to improved properties and characteristics of backbones of macromolecules such as improvement in gel strength, swelling index, mucoadhesion, drug targeting and drug release profile. Therefore, in recent decades grafting of the natural polymer has gained immense importance for the development of drug delivery systems. In addition to the pharmaceutical applications graft copolymers are extensively utilized in diversified fields. The present review is an attempt to define the grafting, various methods of polymer grafting and their application in drug delivery.