Controlling Microscale Collagen Peptide Assembly with Metal Triggers

Purdue University, West Lafayette IN

Investigators

Abstract

Controlling Microscale Collagen Peptide Self Assembly with Metal Triggers Collagen is one of the major structural proteins of the extracellular matrix and is found associated with skin, bone, tendons, ligaments, and blood vessels. As such, there is great interest in using collagen for applications in regenerative medicine and tissue engineering. Natural collagen has limitations, however, for these applications due to difficulties in precisely controlling the protein's structure at the nano- and micro-scale and a limited ability to modify its chemical structure. These difficulties could be overcome by using synthetic fragments of collagen (peptides) as building blocks for larger, functional biomaterials. To this end, the Chmielewski group has designed collagen peptide building blocks that can be assembled using metal ion/ligand interactions to generate unique micron-scaled structures, such as fibers, spheres, meshes and disks. The overall goals of the proposed research are to understand the mechanism used in the formation of the collagen peptide assemblies and to fully optimize the conditions needed to generate distinct collagen peptide microstructures on demand. Specific questions that will be addressed include: (1) What roles do the metal-ligand combination and the chemical structure of the collagen building block play in the assembly of nano- to micro-scaled structures? (2) What is the mechanism of the formation of the collagen peptide microstructures? (3) Can features of different building block design strategies be combined to create modular microstructures? The initial designs of collagen peptide assembly using metal-ligand interactions have provided fascinating microstructures, some of unprecedented sizes and shape. The intellectual merit of the proposed studies is focused on gaining a firm understanding of the parameters and mechanisms of the assembly process. The metal-promoted assembly of collagen peptides into micro-scale materials is evocative and may have broad impact on many areas of science, including bio-nanotechnology, tissue engineering and drug delivery. The results of the proposed scientific questions will, therefore, have a broad impact on society, as will the training of the students who participate in this interdisciplinary area of research.