Polyelectrolytes under spatial and dielectric confinement

Understanding the conformational behavior of polyelectrolytes inside viral capsids and lipid vesicles is crucial for gene delivery and drug loading applications. In this talk, we focus on the collective effects of dielectric mismatch and spatial confinement on the conformational behavior of a model polyelectrolyte chain and counterions confined in a spherical cavity. We show that surface polarization due to dielectric mismatch between the media inside and outside the cavity influences the chain conformational behavior. Specifically, it is found that surface polarization increases the work required to change the equilibrium (unconfined) chain conformation and favors the collapsed conformations with smaller size. The roles of surface charge density, electrostatic strength between the monomers and counterions and multivalent counterions are also discussed. The findings therein offer insights into the effects of dielectric mismatch, which were often overlooked in previous studies on confined polyelectrolytes.