Pharmaceutical and Biomedical Applications of Native and Modified Starch: A Review.

Starch is a natural, renewable, and biodegradable polymer produced by many plants as a source of stored energy. The structural and functional diversity of starches makes them suitable for different applications. Various physical, chemical, and enzymatic modifications can change and improve functional properties of starch to facilitate its use for different pharmaceutical purposes. Currently, some types of starches—for example, native starch, sodium starch glycolate (chemically modified starch), and pregelatinized starch (physically modified starch)—are approved by the United States Food and Drug Administration (FDA) for use either as an isolated excipient or as a matrix for drug delivery systems in granules, capsules, tablets, suppositories, implants, stents, transdermal, and ophthalmic systems. However, the increasing number of drug moieties with varying physicochemical and stability properties along with the development of new drug production processes and drug delivery systems exert pressure on formulators to search for new excipients that achieve the desired set of functionalities. This paper offers a clear overview of native and modified starches and their use in pharmaceutical and biomedical applications, either as excipients or as drug delivery systems. In addition, some drug release mechanisms, which include encapsulants, micro/nanoparticles hydrogels and scaffolds, are discussed. [ABSTRACT FROM AUTHOR]