Preparation and Evaluation of Cross Linked Starch Urea- A New Polymer for Controlled Release of Aceclofenac

Abstract

The objective of the present investigation is to synthesize cross linked starch-urea, a new starch based polymer and to evaluate its application in controlled release and in the design of aceclofenac controlled release tablets. Starch-urea (carbamate) was prepared by gelatinizing potato starch in the presence of urea. The starch-urea was then cross linked by treatment with calcium chloride to result in cross-linked starch-urea. Matrix tablets each containing 100 mg of aceclofenac were formulated employing (i) starch-urea and (ii) cross-linked starch-urea in different proportions by wet granulation method and the tablets were evaluated. Cross-linked starch-urea was more suitable than starch-urea for controlled release application. Aceclofenac release from the matrix tablets formulated employing cross-linked starch-urea was slow, spread over 24 h and the release was diffusion controlled. Non-Fickian diffusion was the drug release mechanism from these matrix tablets. Aceclofenac release from matrix tablets (F3) formulated employing 50 % cross-linked starch-urea was similar to that from hifenac SR tablets, a commercial SR formulation of aceclofenac. Aceclofenac CR tablets for once-aday (24 h) administration could be designed employing cross-linked starch-urea.