Fluorophores with a Genome: DNA-Stabilized Silver Clusters as a New Class of Tunable Fluorophores for Microscopy and Biosensing
Because near-infrared (NIR) electromagnetic radiation penetrates much farther into biological tissues than visible light, NIR microscopy allows for noninvasive imaging deep into tissues and even whole organisms. In the second near-infrared window (NIR-II: 1,000-1,700 nm), biological tissues are transparent up to several centimeters depth. However, fluorescence microscopy in this spectral window has been limited by the dearth of small, bright, and nontoxic NIR-II fluorophores. To address this challenge, we are investigating a promising class of nanomaterials – DNA-templated silver clusters (Ag-DNAs) – to develop small, stable, and modular NIR-II biolabels with broad applicability for deep tissue imaging. Ag-DNAs represent a diverse palette of fluorophores with sequence-encoded sizes of 10-30 atoms and fluorescence emission wavelengths of 400 – 1,000 nm. I will discuss our growing understanding of the fundamental properties of Ag-DNAs and our development of a high throughput experimental platform coupled with machine learning frameworks to guide discovery of Ag-DNAs within the NIR spectral windows. Using this approach, we are expanding the color palette of Ag-DNAs well into the NIR, with exciting future potential to enable deep tissue imaging applications.
Stacy Copp is an Assistant Professor of Materials Science and Engineering at the University of California, Irvine, where she holds the Samueli Faculty Development Chair and courtesy appointments in the Departments of Physics and Astronomy and Chemical and Biomolecular Engineering. Her research focuses on harnessing information-encoding macromolecules – DNA, peptides, and block copolymers – as building blocks for novel optical and electronic materials. Due to the complexity of these molecular materials, her work incorporates machine learning and data mining for materials study and design. Copp earned a B.S. in physics and mathematics from the University of Arizona (2011) and Ph.D. in physics from UC Santa Barbara. Before joining UCI in 2019, she was a Hoffman Distinguished Postdoctoral Fellow at Los Alamos National Laboratory (LANL). Copp’s research has been recognized by awards including the AFOSR Young Investigator (2020), L’Oreal USA for Women in Science Fellowship (2018), and numerous postdoctoral and graduate fellowships.
Sponsored by the Michael and Roberta Berns Laser Microbeam Program