In-Situ Electron Microscopy of DNA-Guided Self-Assembly and Reconfiguration of 3D Nanocrystal Superlattices
Abstract
Solution-phase self-assembly of nanoparticles into mesoscale structures via engineered nucleic acid linkers is a promising strategy for constructing functional materials and dynamically adaptive materials architectures from nanoscale components. The underlying processes remain poorly understood. Conventional approaches of studying self-assembly can assess only the final assembly outside the native solution environment (e.g., by ex-situ electron microscopy) or follow the degree of ordering (in- situ diffraction) but do not provide access to real-space dynamics, especially at small scale. Here, we propose to use real-time observations by in-situ liquid-cell electron microscopy (LCEM) coupled with numerical simulations in a research program aimed at establishing the fundamental mechanisms, pathways, and forces that govern DNA-guided nanoparticle self-assembly and the dynamic reconfiguration of nanocrystal superlattices in their native liquid environment. To actively influence assembly and reconfiguration during observation, we will deploy novel experimental platforms comprising liquid cells with complex fluidic capabilities for controlled release and mixing of solutions. This will enable us to probe the effects of a comprehensive range of external stimuli such as changes in temperature, polarity, ionic strength, and modifications to DNA shells and linkers. Finally, we propose LCEM experiments to investigate biomimetic mineralization within soft assemblies to develop fixation pathways that will enable their use in dry environments. The proposed research will provide a fundamental understanding of the interactions between spherical nanocrystal-nucleic acid conjugates and the associated self-assembly and reconfiguration mechanisms, pathways, possible kinetic bottlenecks and novel avenues to avoid them. Quantitative analysis of the in-situ microscopy data will support the development of realistic models capable of accurate predictions for complex nanocrystal-based materials architectures and adaptive systems with dynamically programmable properties. The results of this project will thus contribute to the realization of critical defense related capabilities, such as the ultra-sensitive detection of chemical and biological agents, manipulation of the electromagnetic spectrum and photonic cloaking, the development of autonomous inorganic ÔorganismsÕ, and novel approaches to quantum information processing.
Document Details
- Document Type
- DoD Grant Award
- Publication Date
- Oct 17, 2018
- Source ID
- W911NF1710141
Entities
People
- Eli Sutter
Organizations
- Army Contracting Command
- United States Army
- University of Nebraska–Lincoln