Patent ID: 6071447
Filing Date: 2000-06-06
Classification: A61F,A61K,A61L,C08G

Abstract:
A method for preparing a polymeric delivery vehicle for controlled-release of a bioactive agent comprising the steps of:treating with a cross-linking agent a biopolymer containing chemically reactive functionalities which react with said cross-linking agent, wherein said cross-linking agent comprises greater than two reactive sites per molecule which are chemically reactive with said functionalities, to form a cross-linked biopolymer;wherein said treating step is conducted in the presence of a protic solvent whereby a gaseous side product is evolved, whereby said cross-linked biopolymer is formed as a foam;optionally, forming said cross-linked biopolymer into a desired shape;contacting said cross-linked biopolymer with a solution containing said bioactive agent to noncovalently bind at least a portion of said bioactive agent to said cross-linked biopolymer to form said polymeric delivery vehicle, wherein the rate of release of said bioactive agent is controlled by the binding affinity of said cross-linked biopolymer with said bioactive agent, and wherein said binding affinity is above 0.8.