Internal structure in systems of self-coacervating polymers

Liquid-liquid phase separation (LLPS) has been shown to play a central role in many

essential biological processes, including RNA synthesis, immune and stress

response, and metabolic acceleration. It has also been harnessed to aid in

technological applications such as targeted drug delivery and microencapsulation.

Although charge patterning and hydrophobic interactions have been suggested as

deciding factors in the formation of LLPS and their internal structure, their exact

strength and interplay remains elusive. In this talk, we present the results of our

computational study using a highly coarse-grained polymer model containing

polycation, polyanion, and uncharged blocks with explicit monomer polarizability.

Through systematic variation of monomer polarizability and the arrangement of the

blocks of the copolymer, we show a strong dependence of coacervate stability on

these parameters. We show how uncharged, polar domains can lead to self-

assembled microstructures within the polymer-rich phase. Our results provide

insight into the design of LLPS systems that contain internal structure, which can

help design our own coacervate phases with controllable and fine-tuned phase

behavior.