CHARACTERIZATION OF MODIFIED ALGINATE-POLY-L-LYSINE MICROCAPSULES

Various modifications of alginate-poly-L-lysine microcapsules were mad e, such as the inclusion of polyethylenimine (PEI) or carboxyl methyl cellulose (CMC) in the core and the coating of bis(polyoxyethylene bis [amine]) (PEGA) onto the microcapsule membrane surface. A characteriza tion of the modified microcapsules in terms of mechanical and mass tra nsfer properties as well as their chemical composition was performed. The PEI treatment greatly enhanced the mechanical stability of the mic rocapsules, and this treatment did not affect the coating process of p oly-L-lysine or PECA. PEGA was found to be able to coat the microcapsu les while the mass transfer property was similar to the poly-L-lysine coated ones.