Assemblage of novel release modules for the development of adaptable drug delivery systems

The aim of this paper was to study the applicability of the release module assemblage technology for an adaptable control of drug delivery rate and site. The elementary release module was a swellable matrix having one base convex and the other concave, named Dome Matrix (R). The swelling and release behavior of the release module was studied. The presence of the convex and concave bases in the swellable matrix slightly changed the overall drug delivery kinetics exhibited by a flat base cylindrical matrix having the same weight and composition. The swelling and drug release of the individual bases of the matrix was also studied to investigate the effect of the surface shape. The concave, convex and flat bases exhibited different swelling and release kinetics. The convex base released drug at faster rate than the concave base, whereas the flat base was intermediate. The release mechanisms of convex and concave bases were significantly different. The Dome Matrix (R) module was selected for assembling several modules in a delivery system obtained by a guided insertion of the convex base into the concave base or by concave/concave base sticking. The module assemblage shows different drug release behavior depending on the geometry of assembled systems. (c) 2005 Elsevier B.V. All rights reserved.