Article

Studies on bioadhesive granules II. Granules formulated with Mucuna flagillepes (mucuna) gum

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Abstract

Mucuna gum extracted from the seeds of the tropical plant, Mucuna flagillepes was assessed for the bioadhesive delivery of theophylline. Theophylline containing granules were formulated by wet granulation, and thereafter, subjected to a bioadhesive test using adhesion on porcine jejunum. The bioadhesive properties of the gum dispersions were also assessed using coated glass beads and a tensiometer. Also, the physical properties of the film formulated from the gum were evaluated. Sodium carboxymethylcellulose (SCMC) and acacia gum were used as standard bioadhesive polymers. Results obtained indicated that mucuna gum is much more bioadhesive than acacia gum, but less bioadhesive than SCMC at equivalent concentration with respect to coated glass beads test; however, mucuna gum was more bioadhesive with respect to the tensiometric evaluation of the bioadhesive strength. The bioadhesive force recorded for mucuna gum may probably be high enough for the bioadhesive delivery of theophylline as the release study results show. SCMC had better film-forming properties than either mucuna gum or acacia gum. Ex vivo study showed that theophylline could be released from the granules.

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