Designing peptide-based complex coacervates for protein and virus encapsulation*

Complex coacervates have served as a versatile materials platform for exploring the material microenvironment, facilitating a wide range of biochemical and biomedical applications. These applications span from biosensing and catalysis to refrigeration-free vaccines. Complex coacervates are formed by the associative phase separation of oppositely-charged polymers, which is driven by an electrostatic attraction and an entropically driven complexation. Here, we design and synthesize various patterned peptides as model polymers to study the role of sequence, hydrophobicity, hydrogen bonding, and encapsulation of model proteins into our coacervates. Additionally, we explore the encapsulation of non-enveloped viruses to understand how the charge, hydrophobicity, and surface patterning chemistry on the virus capsid influence encapsulation. Overall, our systematic and practical approach incorporates sequence effects into our physical understanding of the coacervate system, expanding the range of chemical functionalities available in our peptides.