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Title: Off-axis electron holography of bacterial cells and magnetic nanoparticles in liquid

Abstract

Here, the mapping of electrostatic potentials and magnetic fields in liquids using electron holography has been considered to be unrealistic. Here, we show that hydrated cells of Magnetospirillum magneticum strain AMB-1 and assemblies of magnetic nanoparticles can be studied using off-axis electron holography in a fluid cell specimen holder within the transmission electron microscope. Considering that the holographic object and reference wave both pass through liquid, the recorded electron holograms show sufficient interference fringe contrast to permit reconstruction of the phase shift of the electron wave and mapping of the magnetic induction from bacterial magnetite nanocrystals. We assess the challenges of performing in situ magnetization reversal experiments using a fluid cell specimen holder, discuss approaches for improving spatial resolution and specimen stability, and outline future perspectives for studying scientific phenomena, ranging from interparticle interactions in liquids and electrical double layers at solid–liquid interfaces to biomineralization and the mapping of electrostatic potentials associated with protein aggregation and folding.

Authors:
ORCiD logo [1]; ORCiD logo [2]; ORCiD logo [3]; ORCiD logo [3]
  1. Ames Lab., Ames, IA (United States)
  2. Imperial College London, London (United Kingdom)
  3. Forschungszentrum Julich, Julich (Germany)
Publication Date:
Research Org.:
Ames Laboratory (AMES), Ames, IA (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1406562
Report Number(s):
IS-J-9452
Journal ID: ISSN 1742-5689; TRN: US1703042
Grant/Contract Number:
AC02-07CH11358; (FP7/2007-2013); 320832
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Interface
Additional Journal Information:
Journal Volume: 14; Journal Issue: 135; Journal ID: ISSN 1742-5689
Publisher:
The Royal Society
Country of Publication:
United States
Language:
English
Subject:
36 MATERIALS SCIENCE; 75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND SUPERFLUIDITY

Citation Formats

Prozorov, Tanya, Almeida, Trevor P., Kovacs, Andras, and Dunin-Borkowski, Rafal E. Off-axis electron holography of bacterial cells and magnetic nanoparticles in liquid. United States: N. p., 2017. Web. doi:10.1098/rsif.2017.0464.
Prozorov, Tanya, Almeida, Trevor P., Kovacs, Andras, & Dunin-Borkowski, Rafal E. Off-axis electron holography of bacterial cells and magnetic nanoparticles in liquid. United States. doi:10.1098/rsif.2017.0464.
Prozorov, Tanya, Almeida, Trevor P., Kovacs, Andras, and Dunin-Borkowski, Rafal E. 2017. "Off-axis electron holography of bacterial cells and magnetic nanoparticles in liquid". United States. doi:10.1098/rsif.2017.0464.
@article{osti_1406562,
title = {Off-axis electron holography of bacterial cells and magnetic nanoparticles in liquid},
author = {Prozorov, Tanya and Almeida, Trevor P. and Kovacs, Andras and Dunin-Borkowski, Rafal E.},
abstractNote = {Here, the mapping of electrostatic potentials and magnetic fields in liquids using electron holography has been considered to be unrealistic. Here, we show that hydrated cells of Magnetospirillum magneticum strain AMB-1 and assemblies of magnetic nanoparticles can be studied using off-axis electron holography in a fluid cell specimen holder within the transmission electron microscope. Considering that the holographic object and reference wave both pass through liquid, the recorded electron holograms show sufficient interference fringe contrast to permit reconstruction of the phase shift of the electron wave and mapping of the magnetic induction from bacterial magnetite nanocrystals. We assess the challenges of performing in situ magnetization reversal experiments using a fluid cell specimen holder, discuss approaches for improving spatial resolution and specimen stability, and outline future perspectives for studying scientific phenomena, ranging from interparticle interactions in liquids and electrical double layers at solid–liquid interfaces to biomineralization and the mapping of electrostatic potentials associated with protein aggregation and folding.},
doi = {10.1098/rsif.2017.0464},
journal = {Interface},
number = 135,
volume = 14,
place = {United States},
year = 2017,
month =
}

Journal Article:
Free Publicly Available Full Text
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