A Study of the Swelling of Tablet Excipients Using Video Recording

Abstract

A video recording technique was used to study microscopically the svelling characteristics of individual tablet disintegrant particles in vater. Feret's diameter, projected area and dimensionless shape factors such as elongation ratio, bulkiness factor and surface factor of various particle profiles were determined. Hydrated particles of cross-linked sodium cazboxymethylcellulose (Ac-Di-Sol) and loW substituted sodium carboxymethylcellulose (Nymcel ZSB10 and ZSD16) had high Feret's diameter and projected areas. Swelling in their case vas due to the hydration of macromolecules. Hydrated microcrystalllne CellUlOSe (Avicel PHlOll partlcles had a narrov distribution of both Feret's diameter and projected area. The lov degree of svelling In these particles vas due to entry of vater into particle pores. Fibrous particles of Nymcel ZSB10 retained their elongated shape even after swelling fully. Ac-Di-Sol and Nymcel ZSD16 particles hovever svelled appreciably along their breadth also and assumed a less elongated profile than vhen dry. The order for increase in projected area diameter after hydration was Ac-Di-Sol > Nymcel ZSB10 > ZSD16 > Avicel PH101.