Grewia Gum 2: Mucoadhesive Properties of Compacts and Gels

Purpose: To compare the mucoadhesive performance of grewia polysaccharide gum with those of guar
gum, carboxymethylcellulose, hydroxypropyl methylcellulose and carbopol 971P.
Methods: Grewia polysaccharide gum compacts or gels as well as those of guar gum,
carboxymethylcellulose, hydroxypropyl methylcellulose or carbopol 971P were prepared. Texturometric
and tensile analysis of the polymer gels and compacts were carried out using a software-controlled
penetrometre, TA.XTPlus texture analyzer. The polymer gels were evaluated for hardness, stickiness,
work of cohesion and work of adhesion. Furthermore, the detachment force of the polymer compacts
from a mucin substrate was evaluated.
Results: The work of adhesion of guar gels was significantly greater than that of grewia gels (p < 0.001)
but the latter showed a significantly greater work of adhesion than carboxymethylcellulose gels (p <
0.05) and hydroxypropyl methylcellulose gels (p < 0.001). However, the work of cohesion for
grewia/mucin gel mixture was significantly greater (p < 0.001) than those of
carboxymethylcellulose/mucin, hydroxypropyl methylcellulose/mucin and carbopol 971P/mucin gel
blends. The difference between the mucoadhesive performance of grewia compacts and those of
hydroxypropyl methylcellulose and carbopol 971P compacts was insignificant (p > 0.05).
Conclusion: Grewia polysaccharide gum demonstrated good mucoadhesive properties, comparable to
those of carbopol 971P, carboxymethylcellulose, guar gum and hydroxypropyl methylcellulose, and
therefore, should be suitable for the formulation of retentive drug delivery devices.