The role of polymer membrane formation in sustained release drug delivery systems.

A discussion of the role of polymer membrane-based drug delivery systems is presented. This is followed with a review of recent studies in our laboratories of the membrane formation and drug delivery characteristics of injectable polymer solution platforms. Attention is focused on the role of depot formulation in terms of solvent quality and water miscibility and polymer type (amorphous versus crystallizable), as well as the effects of bath-side additives on the in vitro release behavior. A quantitative model describing the protein release dynamics in fast phase inverting systems (FPI) is also discussed.