Hydrogel for topical drug delivery based on Mimosa pudica seed mucilage: Development and characterization

A Large number of existing excipients had become common place in today's pharmaceutical formulations as additives but had certain drawbacks such as lack of biodegradability, biocompatibility, toxicity, side effects, high cost as well as environmental pollution during synthesis. As the establishment of toxicity and side effects poses a problem with synthetic excipients for the recognition as safe use from regulatory authorities, more interest is attracted towards the development of natural excipients. In the present study, attempts were made to explore mucilaginous polysaccharides isolated from seeds of Mimosa pudica as a hydro-gelling agent as mucilaginous materials obtained from plant sources could be an effective gelling agent. The isolated mucilaginous polysaccharides material was tested for its physicochemical, spectrophotometric, thermal, mechanical, biodegradation, micromeritics properties (like particle size, density, flow properties of powder) and oral toxicity study. The results reveal that isolated mucilaginous polysaccharides had slightly acidic pH, low moisture and ash content and a good swelling index with good micromeritics properties. Rheological properties showed non Newtonian shear thinning behavior. Biodegradation study confirms its easily biodegradable nature at a reasonable rate. The FTIR and NMR spectrum showed its characteristic as polysaccharide moiety. Oral toxicity studies report of M pudica mucilaginous polysaccharide confirms it as GRAS material. Isolated mucilaginous polysaccharide exhibits hydrogel-forming ability at 1% w/w concentration. Diclofenac loaded hydrogel exhibited persistent drug release. These findings demonstrated that the Mimosa pudica mucilaginous polysaccharide could be a suitable excipient as a hydrogel-forming agent not only in drug delivery applications but also in cosmetic industries.