A sustained release composition comprising a multivalent cation cross-linked algenate combined with a polyacrylic acid.

摘要

Alginate beads are employed as a site specific oral delivery system for cationic therapeutic agents, such as TGF- beta 1, designed to target the agents to the luminal side of the small intestine. Improved delivery of bioactive material is obtained by: 1) incorporating selected polyanions in the alginate beads to shield the cationic therapeutic agent from interaction with alginate and/or 2) acid treating alginate beads containing the therapeutic agents to reduce the molecular weight of alginate and its interaction with the agents. Enhanced bioactivity of therapeutic agents released from the alginate is attributed to the ability of polyacrylic acid to shield the agents from interaction with lower molecular fragments of acid treated alginate.