title: Controlled protein release from polyethyleneimine-coated poly(L-lactic acid)/pluronic blend matrices.
abstract: Protein release from degradable polymer matrices, composed of poly(L-lactic acid) and its blends with Pluronic surfactant, was investigated with and without the aqueous coating of an adsorptive water-soluble polymer, polyethyleneimine (PEI). PEI is a highly branched cationic polymer containing primary, secondary, and tertiary amino groups in its backbone. The treatment of PEI for PLA/Pluronic blend films exhibited a remarkable decrease in the "burst" release of protein at an initial stage and a significant extension in the protein release period. Protein release profiles could be controlled by varying PEI treatment time and its concentration. Our results suggest that PEI diffuses into the polymer matrices and crosslinks protein molecules by ionic interactions. Such a PEI-protein network near the surface region of matrix may act as a diffusional barrier for further release of protein molecules.
authors.affiliation: Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge 02139.
authors.forename: T G
authors.initials: TG
authors.lastname: Park
authors.forename: S
authors.initials: S
authors.lastname: Cohen
authors.forename: R
authors.initials: R
authors.lastname: Langer
mesh_terms: D003692:Delayed-Action Preparations; D007773:Lactates / Q000737:chemistry*; D019344:Lactic Acid; D011091:Polyesters; D011094:Polyethyleneimine / Q000737:chemistry*; D011108:Polymers / Q000737:chemistry*; D012710:Serum Albumin, Bovine / Q000493:pharmacokinetics*; D013501:Surface-Active Agents / Q000737:chemistry*
chemical_list: D003692:Delayed-Action Preparations; D007773:Lactates; D011091:Polyesters; D011108:Polymers; D013501:Surface-Active Agents; D012710:Serum Albumin, Bovine; D019344:Lactic Acid; C033616:poly(lactide); D011094:Polyethyleneimine