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Title: Damage-free vibrational spectroscopy of biological materials in the electron microscope

Abstract

Vibrational spectroscopy in the electron microscope would be transformative in the study of biological samples, provided that radiation damage could be prevented. However, electron beams typically create high-energy excitations that severely accelerate sample degradation. Here this major difficulty is overcome using an ‘aloof’ electron beam, positioned tens of nanometres away from the sample: high-energy excitations are suppressed, while vibrational modes of energies o1 eV can be ‘safely’ investigated. To demonstrate the potential of aloof spectroscopy, we record electron energy loss spectra from biogenic guanine crystals in their native state, resolving their characteristic C–H, N–H and C=O vibrational signatures with no observable radiation damage. Furthermore, the technique opens up the possibility of non-damaging compositional analyses of organic functional groups, including non-crystalline biological materials, at a spatial resolution of ~10nm, simultaneously combined with imaging in the electron microscope.

Authors:
 [1];  [1];  [2];  [3];  [4];  [5];  [5]; ORCiD logo [3];  [3]
  1. Arizona State Univ., Tempe, AZ (United States)
  2. Univ. Paris-Sud, Orsay (France)
  3. Weizmann Institute of Science, Rehovot (Israel)
  4. Arizona State Univ., Tempe, AZ (United States); Nion Co., Kirkland, WA (United States)
  5. Nion Co., Kirkland, WA (United States)
Publication Date:
Research Org.:
Rutgers Univ., New Brunswick, NJ (United States)
Sponsoring Org.:
USDOE
OSTI Identifier:
1252902
Grant/Contract Number:
SC0005132
Resource Type:
Journal Article: Accepted Manuscript
Journal Name:
Nature Communications
Additional Journal Information:
Journal Volume: 7; Journal ID: ISSN 2041-1723
Publisher:
Nature Publishing Group
Country of Publication:
United States
Language:
English
Subject:
physical sciences; optical physics

Citation Formats

Rez, Peter, Aoki, Toshihiro, March, Katia, Gur, Dvir, Krivanek, Ondrej L., Dellby, Niklas, Lovejoy, Tracy C., Wolf, Sharon G., and Cohen, Hagai. Damage-free vibrational spectroscopy of biological materials in the electron microscope. United States: N. p., 2016. Web. doi:10.1038/ncomms10945.
Rez, Peter, Aoki, Toshihiro, March, Katia, Gur, Dvir, Krivanek, Ondrej L., Dellby, Niklas, Lovejoy, Tracy C., Wolf, Sharon G., & Cohen, Hagai. Damage-free vibrational spectroscopy of biological materials in the electron microscope. United States. doi:10.1038/ncomms10945.
Rez, Peter, Aoki, Toshihiro, March, Katia, Gur, Dvir, Krivanek, Ondrej L., Dellby, Niklas, Lovejoy, Tracy C., Wolf, Sharon G., and Cohen, Hagai. 2016. "Damage-free vibrational spectroscopy of biological materials in the electron microscope". United States. doi:10.1038/ncomms10945. https://www.osti.gov/servlets/purl/1252902.
@article{osti_1252902,
title = {Damage-free vibrational spectroscopy of biological materials in the electron microscope},
author = {Rez, Peter and Aoki, Toshihiro and March, Katia and Gur, Dvir and Krivanek, Ondrej L. and Dellby, Niklas and Lovejoy, Tracy C. and Wolf, Sharon G. and Cohen, Hagai},
abstractNote = {Vibrational spectroscopy in the electron microscope would be transformative in the study of biological samples, provided that radiation damage could be prevented. However, electron beams typically create high-energy excitations that severely accelerate sample degradation. Here this major difficulty is overcome using an ‘aloof’ electron beam, positioned tens of nanometres away from the sample: high-energy excitations are suppressed, while vibrational modes of energies o1 eV can be ‘safely’ investigated. To demonstrate the potential of aloof spectroscopy, we record electron energy loss spectra from biogenic guanine crystals in their native state, resolving their characteristic C–H, N–H and C=O vibrational signatures with no observable radiation damage. Furthermore, the technique opens up the possibility of non-damaging compositional analyses of organic functional groups, including non-crystalline biological materials, at a spatial resolution of ~10nm, simultaneously combined with imaging in the electron microscope.},
doi = {10.1038/ncomms10945},
journal = {Nature Communications},
number = ,
volume = 7,
place = {United States},
year = 2016,
month = 3
}

Journal Article:
Free Publicly Available Full Text
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Citation Metrics:
Cited by: 5works
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