Effect of Formulation Variables on the Swelling Index of Acyclovir Sustained Release Tablets Using Xanthan Gum and Sodium Alginate

摘要

The swelling index characterizes the rate at which a tablet will dissolute and is also an indicative of the mechanism. The present study focuses on studying the effect of swelling capacity of Acyclovir Sustained release tablets such that for all formulations it increases as increase the concentration of gum in each formulation. The swelling index of all formulation increases as increase the concentration of gum in each formulation. Swelling of matrix tablets increases with respect to time because weight gain by tablets was increased proportionally with rate hydration up to 4hrs and matrix appeared swollen almost from the beginning and a viscous gel mass was created after contact with water later on swelling were decreases due to dissolution of outermost gelled layer of tablets. Swelling index of tablets prepared from ACL3 resulted as better swelling behavior with respect to concentration. It has observed that drug release decreases with increasing concentration of gum and swelling index. The reason attributed to this fact is formation of thick gel layer by matrices around tablets that delays diffusion and release drug. It has observed that swelling index of matrix tablets containing only one natural polymer was less this may attributed to the lower water uptake and less hydrophilicity.