Synthetic Biomaterials

A key attribute of synthetic biomaterials is their ability to mimic naturally occurring biological molecules and systems. The challenge, however, is to generate materials with hierarchical assemblies down to the atomic level that have precisely tailored chemical heterogeneities and external stimuli-responsiveness.

Self-assembling peptides have emerged as a promising avenue for the creation of novel biomaterials. For instance, coiled-coil peptide materials comprising fibers and hydrogels have been described, some of which are capable of supporting cell growth and differentiation for tissue regeneration. Additionally, nanotubes, cages, films, and crystals have also been created for ultimate applications in drug delivery and biosensing.

Researchers in the Chielewski Group, published in JACS, describes a set of coiled-coil peptides, radially functionalized with bipyridines, that demonstrate hierarchical assembly into banded rectangular nano- and microstructures, the dimensions of which vary with the strategic placement and number of aromatic groups on the monomer backbone.

Finer structural aspects of the hexagonal packing of the individual trimers were determined by X-ray scattering, including intertrimer aromatic interactions between bipyridine moieties. The ease of formation of these biomaterials under physiological conditions and the use of pH to reversibly modulate assembly demonstrate future potential for a range of biological applications, such as drug delivery in a pH-controlled manner.

Reversible Hierarchical Assembly of Trimeric Coiled-Coil Peptides into Banded Nano- and Microstructures
Monessha Nambiar, Li-Sheng Wang, Vincent Rotello, and Jean Chmielewski
J. Am. Chem. Soc., 2018, 140 (40), pp 13028-13033