Preparation and Evaluation of Controlled Release of Eperisone Hydrochloride Resinate Beads by Complexing with Ion Exchange Resin

Abstract

Complexes of ion-exchange resins and Eperisone hydrochloride, a model drug, were prepared using a batch method with different functional groups, loading equilibrium time, degree of cross linking, and resin particle size. Drug loading efficiency, mircromeritics properties and study of effect of cross linking and particle size on release behaviours, were also investigated. Most of the functional groups of resins were loaded with EpeH after the completion of a single batch method and it was recommended for drug loading into the ion-exchange resin. Using a batch method, drug loading could be monitored by simply measuring changes in the pH of the reaction medium since as complex formation reached completion, the pH returned to the initial pH of the eluent due to the limited amount of functional groups available for the exchange. EpeH could be loaded up to the ratio of 1 (drug): 1 (resin), depending on the physicochemical properties of the resin. As the cross linking ratio and particle size increased, release rate decreased due to the reduced effective diffusion coefficient and surface area.