Hierarchichal self assembly is the hallmark of biological materials such as collagen, but designing synthetic structures that do this is a challenge. Bioinspired peptoid diblock copolymers that braid themselves into a nanoscale rope have been developed by Ronald Zuckermann and co-workers, University of California, Berkeley, USA.

The polypeptides first self-assemble into sheets, these then form lamellar stacks which roll up into double helices, resembling a rope and measuring around 600 nm. The internal ordering of the stacks is controlled by the crystalline aromatic side chain−side chain interactions within the hydrophobic block.

The tunability of this system, through the side chains, allows control over the length and precise sequences of the helices. This opens the door for the development of synthetic structures that mimic biological materials’ ability to recognize specific protein forms, for example.

• Hierarchical Self-Assembly of a Biomimetic Diblock Copolypeptoid into Homochiral Superhelices
  H. K. Murnen, A. M. Rosales, J. N. Jaworski, R. A. Segalman, R. N. Zuckermann,
  J. Am. Chem. Soc. 2010, 132(45), 16112–16119.
  DOI: 10.1021/ja106340f