Exploring cross-linked tragacanth as novel excipient-proof-of-concept

Background: Tragacanth, a natural gum, is frequently used as stabilizer for colloidal systems and as a binder in tablets. Materials from natural sources are in increasing demand to solve the current global environmental problems arising from synthesis involving petroleum-based substances. Objectives: In this context, we improved functionality of tragacanth through crosslinking and extended its application for directly compressed fast dissolving systems. Fast dissolving formulations upon settling on the tongue disintegrate promptly and release the medicament, thus making it especially suitable for paediatrics, geriatrics, bedbound, or incapacitated patients. Materials and Methods: Cross-linked tragacanth (CLT) was explored as a potent disintegrant and compared with sodium starch glycolate and Crospovidone for its effect on compressibility and release of metoclopramide hydrochloride from tablets made by direct compression and sublimation method. Formulations made using CLT were optimized for swelling capacity, absorption efficiency, and moisture sorption capacity. Results: The most appropriate controls for linkage of tragacanth were 1:0.4 proportion of tragacanth: Epichlorohydrin, at 105°C temperature for 45 min of reaction. Prepared formulations showed desired disintegration and wetting time. Formulations made using camphor showed porosity because of sublimation and favored rapid disintegration. Based on the drug release study, it is confirmed that formulation with 4% CLT and 20% camphor prepared by sublimation process exhibited highest drug release, i. e. 99.23% within 15 min. Conclusion: This study demonstrates the novel applicability of tragacanth as an effective natural superdisintegrant after cross-linking and provides a sustainable alternative to synthetic superdisintegrants while formulating the fast-disintegrating tablets.