Shape-Shifting Peptide-Based Nanomaterials

With the support of the Macromolecular, Supramolecular and Nanochemistry Program in the Division of Chemistry, Professor Vincent Conticello of Emory University will investigate the design, structure, and functional properties of shape-shifting nanomaterials derived from peptides that mimic natural tissues. They are capable of changing their shape in a defined manner in response to changes in their local environment.

The materials will be designed to form two-dimensional, sheet-like structures that can roll up reversibly to form tubes or other more compact structures. The reversibility of this process is promising in creating nanomaterials that can be tailored for societally important applications such as the controlled encapsulation and delivery of therapeutic agents.

This project will involve skills drawn from scientific disciplines including chemistry, materials science, and biology. Students involved in this project will receive training in cutting-edge research methods in peptide design and the structural analysis of nanomaterials, which will prepare them intellectually for the challenging scientific problems encountered in the twenty-first century workforce.

Scientific material related to the proposed research will be presented in a newly developed introductory core course, CHEM 204, and its associated laboratory experience, which focuses on macromolecular structure and function.

The controlled fabrication of functionally responsive assemblies remains a key contemporary challenge in nanoscience. While sequence-defined polymers (e.g., peptides, proteins, and structurally related foldamers) are promising building blocks for constructing a myriad of assemblies with excellent nanoscale structural order, the ability to reliably and predictably encode responsive behavior and higher-order function lies beyond current synthetic capabilities, especially when compared to the multicomponent macromolecular machines of living systems.

This proposal describes and develops an approach to the design of shape-shifting nanomaterials through fabrication of two-dimensional peptide assemblies that display surface asymmetry. The central hypothesis of the proposal will focus on the concept that surface asymmetry in designed peptide assemblies can be employed as a mechanism to introduce unbalanced surface stresses, which can be manifested at the meso-scale in terms of reversible and controllable morphological transitions.

Three aims are described to investigate the structural scope of the process and investigate the potential of shape-shifting for materials applications. It is envisioned that the proposed structures will provide new opportunities for creation of dynamically responsive materials that can be tailored for specific applications that include controlled capture and release of substrates, gated catalysis and energy transduction, through incorporation of molecular mechanisms that can actuate this higher-order structural transition.

This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.