Interparticle Interactions in Dilute Solutions of Polyelectrolyte Complex Micelles

The application of dilute solutions of polyelectrolyte complex micelles for delivering therapeutic nucleic acids into disease sites has gained momentum. This letter reports a detailed characterization of PEC micelles in dilute solutions including their internal structures and the determination of the interparticle interactions. We found that the soft corona chains tethered on the surface of phase-separated complex domains are compressed when micelles come close, at which point a hard-sphere interaction takes over. These findings contribute to the fundamental understanding of the structure and space-filling constraints in the complexation-driven self-assemblies and advance the rational design of cationic polymer-based non-viral nanocarriers.