MODIFICATION OF MYRIANTHUS ARBOREUS GUM: EFFECT ON DISINTEGRATION AND IN VITRO RELEASE OF METRONIDAZOLE FROM TABLET FORMULATION

Modification of natural polymer can lead to improvement of polymer properties. Gums can be modified by physical and chemical methods. The aim of this study was to examine the effect of modification of Myrianthus arboreus gum on disintegration and in vitro release of metronidazole from tablet formulations. The gum was extracted, modified by acid treatment and Carboxymethylation, and used as a binder in metronidazole tablet formulations at concentrations of 2.5% w/w, 5% w/w and 10% w/w. The granule properties were evaluated for bulk and tapped densities, Carr’s index, Hausner’s ratio and angle of repose. The properties of tablets formulated with the modified gums were compared with tablets formulated with sodium alginate and the unmodified native gum. The results showed that carboxymethylation of Myrianthus arboreus gum led to faster disintegration and drug release. Batch B10 containing 2.5% w/w carboxymethylated Myrianthus arboreus gum (C-MAG) disintegrated in less than 2 minutes and released over 80% of metronidazole in 15 minutes. While acid modification of Myrianthus arboreus gum led to slower disintegration and drug release. Metronidazole tablets formulated with 5% w/w and 10% w/w of acid modified Myrianthus arboreus gum (A-MAG) gave disintegration time of 40.33 minutes and 46.35 minutes, respectively, while drug release in 15 minutes for 5% w/w and 10% w/w were 57% and 16%, respectively. It can be concluded from the study that modification of Myrianthus arboreus gum could lead to multi-functional excipients for drug delivery systems by altering the physicochemical properties of the gum.