(619e) Coacervate Driven Assemblies Using α-Helical Polypeptides

Authors: 
Priftis, D., University of Chicago
Song, Z., University of Illinois
Perry, S. L., UMass Amherst
Margossian, K. O., University of Chicago
Tropnikova, A., University of Chicago
Tirrell, M., University of Chicago
Leon, L., Argonne National Laboratory

A variety of materials with diverse structures and properties can form as a result of electrostatic interactions between oppositely charged macromolecules. Under defined conditions, complexation can lead to a phase separation phenomenon, referred to as complex coacervation. Using polypeptides, derived from amino acids, as a model system we identified the external parameters that affect coacervation,1 explored the thermodynamics of coacervate formation,2 and studied the rheological3 and interfacial properties4 of polypeptide coacervates. Here, we focus on the self-assembly of a different type of polypeptides. These water-soluble ultra-stable α-helical polypeptides are produced by elongating the charged side chains from the polypeptide backbone. Under similar conditions, mixing of these helical polypeptides with oppositely charged polyelectrolytes leads to the formation of liquid complexes (complex coacervates). Using the same strategy, coacervate core micelles are formed when the helical polypeptides are linked to a neutral hydrophilic block and are mixed with homopolymers of the opposite charge. The effects of salt, chirality and block length on both self-assembly structures will be discussed.

1. Priftis D., Tirrell M., Soft Mater 2012, 8, 9396-9405.                                                                                                

2. Priftis D., Laugel N., Tirrell M., Langmuir 2012, 28, 15947-15957.                                     

3. Priftis D., Megley K., Laugel N., Tirrell M., J. of Colloid and Interface Sci. 2013, 398, 39-50.                                

4. Priftis D., Farina R., Tirrell M., Langmuir 2012, 28, 8721-8729.