Mixtures of positively and negatively charged biomolecules often associate into two or three dimensional ionic structures. Ionic co-assembly of biomolecules is exceedingly important in biology, given that most biomolecules are charged and hydrophobic. Biomolecule assemblies have finite size, and the molecules have large excluded volumes, giving rise to specific structures. In mixtures of heterogeneous biomolecules we find new surface patterns of charged domains. The interaction of ionic co-assemblies with charged domains can be long range, and break the symmetry of the system, an important concept in biological functions.

Department of Materials Science, Northwestern University