Guar gum: Versatile natural polymer for drug delivery applications
Guar gum a non-ionic polysaccharide obtained from the seeds of Cyamopsis tetragonolobus of the Leguminosae family is found abundantly in nature. It finds extensive use in a variety of fields such as food industry, textile industry, paper industry, cosmetic industry, pharmaceutical industry among many others. Guar gum being a natural polymer with several interesting properties like biodegradability, biosafety, biocompatibility and sustainability presents a potential case for use in pharmaceutical formulations and drug release studies. Although guar gum in its native form finds limited use as delivery carriers owing to its high swelling characteristics in aqueous medium, this property can be significantly altered through derivatization of functional groups, cross-linking and grafting for application in a wide spectrum of biomedical fields. This review article provides a comprehensive overview of different modifications made on guar gum through derivatization in the quest to make them more versatile for drug delivery applications. The drug entrapment efficacy and in vitro drug release from different micro- and nano-formulations using guar gum for controlled release are also assessed.