Design and evaluation of glipizide CR tablets employing starch acetate as rate controlling matrix former

Background/Objectives

In the present work, starch acetate was synthesized, characterized and evaluated as effective release retarding matrix materials.

Methods

Matrix tablets of glipizide were formulated employing starch acetate in different proportions of drug and polymer and the tablets were evaluated for drug release kinetics and mechanism.

Results

Starch acetate (SA) was prepared by acetylation of potato starch with acetic anhydride in alkaline medium. The percent acetylation was 42.38% and the degree of substitution was 2.75. Glipizide (10 mg) matrix tablets prepared using starch acetate as matrix former in different concentrations gave slow and controlled release more than 24 h. Glipizide release from the tablets formulated was slow and depends on the concentration (%) of starch acetate in the matrix tablets and nature/type of diluent. A linear relationship was found out between percent of polymer, starch acetate and release rate (K₀) of the tablets. The controlled release characteristics of the starch acetate matrix tablets of the drug remained unaltered during short time accelerated stability study.

Conclusions

Starch acetate was found suitable as matrix former for controlled release and the matrix tablets of glipizide formulated employing starch acetate gave controlled release of glipizide over 24 h.