The efficacy of mucilage obtained from A. indica as a pharmaceutical excipient for sustained release matrix tablets was established. Gum mucilage was isolated from the bark of A. indica. The rheological behavior of the obtained gum mucilage was compared with other gums. The mucilage was further subjected to physicochemical characterization. Also, a comparative study on binding properties of gum mucilage and starch was performed. The gum mucilage obtained from the A. indica exhibited superior rheological properties. The physicochemical characterization showed good flow properties and excellent swelling ratio. The dried mucilage was evaluated as a matrix-forming material for oral sustained-released tablets using diclofenac sodium as a model drug. The diclofenac sodium tablets were prepared using dried mucilage of A. indica in various drug–mucilage ratios. The physical tests like hardness test, friability, and weight variation were performed for all formulations and found to be within the pharmacopoeial limits. The study of dimensional changes in the tablets was also carried out for 5 h in distilled water and the radial and axial swellings of the tablets were found to be increasing with increase in the proportion of the dried mucilage. The study supported the utility of A. indica gum mucilage as a cheap, economic and easily available tablet excipient of natural origin.
