Directing the Mineralization of Inorganic Nanomaterials using Programmable Macromolecular Building Blocks

Abstract

Sequence-defined building blocks such as peptides, proteins, and peptoids offer a path toward the construction of precision materials by enabling the organization, mineralization and dynamic reconfiguration of organic and inorganic components through engineered functions. With thermoresponsive elastin-like polypeptides (ELPs) fused to solid-binding peptides, we demonstrate the biomimetic mineralization of highly uniform and positively charged silica nanoparticles that support the one-step assembly of mono- and bi-material superstructures with highly integrated components. Using gold-binding ELPs, we synthesize gold nanoparticles that can be reversibly assembled into clusters with distinct plasmonic signatures in response to temperature change. For both systems, we study how protein sequence and concentration, solution conditions, and temperature affect mineralization outcomes and plasmonic responses. In collaborative work, we transfer learnings from solid-binding peptides to peptoids by designing a polymeric analog of the R5 silicifying peptide. The biomimetic approaches to the synthesis of size- and composition-controlled nanomaterials described herein are simple and environmentally friendly, and the extracted design rules should prove useful for the biological fabrication of a broad range of hierarchical systems with applications in biomedicine and energy-related fields.