Preparation of Highly Stable Biodegradable Polymer Micelles by Coating with Polyion Complex

Abstract

Abstract Positively charged core/shell type polymer micelles were prepared from a biodegradable amphiphilic block copolymer, poly( L ‐lysine) ‐block‐ poly( L ‐lactide). Polyanion‐coated biodegradable polymer micelles were then prepared via polyion complex (PIC) formation with polyanionic hyaluronic acid (HA) on the positively charged micelles. Characterization of the acquired HA‐coated micelles was carried out via dynamic light scattering, atomic force microscopic observation and ζ ‐potential measurements. The HA‐coated micelles exhibited extremely high stability against dilution and colloidal stability. The PIC‐coated micelle system with high stability would be a useful drug delivery vehicle able to survive long‐term circulation in the bloodstream. magnified image