PROPERTIES, PHARMACEUTICAL APPLICATION AND VARIOUS TECHNIQUE OF CHEMICAL MODIFICATION IN NATIVE STARCH: A DESCRIPTIVE REVIEW

Starch is one important natural polymer that finds application in the formulation of dosage forms as the binder, disintegrates, diluents, gelling agent etc. Starch is drawing the attention in drug delivery as it is cheap, non-toxic, renewable, biodegradable and compatible with many other materials for industrial application. Starch has vital intrinsic properties that have made its pharmaceutical applications possible. It has also been used for a wide range of particular drug delivery applications, such as the delivery of challenging molecules and targeting to specific sites in the body. Starches are integrally unsuitable for most applications such as loss of viscosity and thickening power upon cooking and storage, retrogradation characteristics and absence of certain groups responsible for a particular function etc. So, in order to reduce its limitations and improve its applications, modification of starch is necessary. It can be modified by several ways like chemical modification, physical modification and genetic modification but the most important one is the chemical modification. This review summarizes the properties and application of native starchin conventional drug delivery systems within a world of dynamic drug production technology. It also describes the chemical modification like cross-linking, esterification, etherification and dual modification of starch.