Carboxymethyl starch as a polymeric plant based excipient in drug delivery

Abstract

Polysaccharides extracted and isolated from plant products serve as potential candidates in pharmaceutics mainly drug delivery, owing to its biodegradability, bioavailability and non-toxic character. Hydrogels, three-dimensional hydrophilic polymeric networks, exhibit dramatic changes in their swelling behaviour, network structure, and mechanical strength in response to different stimuli to the body. A wide variety of polysaccharides (chitosan, alginate, cellulose, starch, etc) and their derivatives have been used to synthesize hydrogels that tend to swell in water or biological fluids. Such systems have numerous biomedical applications including: drug delivery, wound dressing, and tissue engineering. However, single-network hydrogels have weak mechanical properties and slow response at swelling. To enhance the mechanical strength and swelling/deswelling response of hydrogels, multicomponent networks as interpenetrating polymer networks have also been reported and recently have gained much importance in research on different biomedical applications. The present review focuses on the application of carboxymethyl starch as a pharmaceutical excipient where the effect of crosslinking modification and the formation of Semi Interpenetrating Polymer Network with montmorillonite clay mineral have been investigated.