Sponsor
Arash Farhadi was supported by the NSERC graduate fellowship. Research in the Shapiro lab was supported by the National Institutes of Health (R01EB018975), the Packard Fellowship in Science and Engineering, the Pew Scholarship in the Biomedical Sciences and the Heritage Medical Research Institute. The Nadeau lab was supported by the Gordon and Betty Moore Foundation (Grant #4038) and the National Science Foundation (NSF) 1828793. Portions of this work were supported under a contract from the Jet Propulsion Laboratory (JPL), California Institute of Technology, under a contract with the National Aeronautics and Space Administration (NASA).
Published In
Nano Letters
Document Type
Post-Print
Publication Date
10-2020
Subjects
Contrast media (Diagnostic imaging), Holographic Images -- Optics, Image processing, Digital holographic microscopy, Phase-contrast microscopy, Reporter genes
Abstract
Quantitative phase imaging and digital holographic microscopy have shown great promise for visualizing the motion, structure and physiology of microorganisms and mammalian cells in three dimensions. However, these imaging techniques currently lack molecular contrast agents analogous to the fluorescent dyes and proteins that have revolutionized fluorescence microscopy. Here we introduce the first genetically encodable phase contrast agents based on gas vesicles. The relatively low index of refraction of the air-filled core of gas vesicles results in optical phase advancement relative to aqueous media, making them a “positive” phase contrast agent easily distinguished from organelles, dyes, or microminerals. We demonstrate this capability by identifying and tracking the motion of gas vesicles and gas vesicle-expressing bacteria using digital holographic microscopy, and by imaging the uptake of engineered gas vesicles by mammalian cells. These results give phase imaging a biomolecular contrast agent, expanding the capabilities of this powerful technology for three-dimensional biological imaging.
Rights
This document is the unedited author's version of a Submitted Work that was subsequently accepted for publication in Nano Letters, copyright © American Chemical Society after peer review. To access the final edited and published work, see https://pubs.acs.org/doi/10.1021/acs.nanolett.0c03159.
DOI
10.1021/acs.nanolett.0c03159
Persistent Identifier
https://archives.pdx.edu/ds/psu/34366
Citation Details
Published as Nano Lett. 2020, 20, 11, 8127–8134. Publication Date:October 29, 2020. https://doi.org/10.1021/acs.nanolett.0c03159