DNA-Protected Silver Clusters for Atomically Precise Nanophotonics and Wiring

University Of California-Santa Barbara, Santa Barbara CA

Investigators

Abstract

The project focuses on tiny particles of 10-30 silver atoms that are encapsulated by strands of DNA. These silver 'clusters' glow in colors set by their size and elongated shapes, which are determined by the sequence of the DNA that wraps around the cluster. The project seeks to control the color-determining cluster geometries within new types of nanometer scale, DNA-based materials that employ silver clusters to manipulate light. Potential applications range from cluster signaling of molecular events around the DNA, to biological imaging in the infrared tissue window, to sensing of disease-related DNA. Additionally, the research aims to develop techniques for merging silver clusters into connected patterns on 'scaffolds' built from DNA, for development of nanoscale antennas and wiring to sense and perhaps even manipulate biomolecular events important to life. Broader participation in science and technology is promoted by development of related 'miniclasses' for presentation to high school students who attend the Saturday sessions of the University of California-Santa Barbara's School for Scientific Thought. Transfer students from California Community Colleges (CCC) are sought to participate in the research, with special efforts to reach underrepresented students. The project aims to develop atomically precise metal cluster photonics using DNA scaffolds to arrange multicolor assemblies of DNA-stabilized silver clusters, 'AgN-DNA', at separations below 10 nm. Efforts to achieve longer, infrared AgN-DNA build on techniques for identifying composition via high-performance liquid chromatography together with high resolution mass spectrometry (MS). Methods to achieve finer, patterned metallization of DNA scaffolds are sought through the approach of anchoring longer silver cluster rods in AgN-DNA onto DNA scaffolds in select geometries. Understanding of the key interactions of silver cations, Ag+, with DNA bases is developed through mass spectroscopic studies of select DNA oligomers and comparison to advanced quantum chemical calculations carried out by international collaborators. Miniclasses for high school students will be presented at the University of California-Santa Barbara's School for Scientific Thought. In addition, transfer students from California Community Colleges (CCC) are sought to participate in the research, with special efforts to reach underrepresented students.