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Updated: May 24, 2026

Use of Electron Paramagnetic Resonance in Biological Samples at Ambient Temperature and 77 K
Published on: January 11, 2019
Real sample temperature: a critical issue in the experiments of nuclear resonant vibrational spectroscopy on
Hongxin Wang1, Yoshitaka Yoda, Saeed Kamali
1Department of Chemistry, University of California, 1 Shields Avenue, Davis, CA 95616, USA. hxwang2@lbl.gov
Abstract:
There are several practical and intertangled issues which make the experiments of nuclear resonant vibrational spectroscopy (NRVS) on biological samples difficult to perform. The sample temperature is one of the most important issues. In NRVS the real sample temperatures can be very different from the readings on the temperature sensors. In this study the following have been performed: (i) citing and analyzing various existing NRVS data to assess the real sample temperatures during the NRVS measurements and to understand their trends with the samples' loading conditions; (ii) designing several NRVS measurements with (Et(4)N)[FeCl(4)] to verify these trends; and (iii) proposing a new sample-loading procedure to achieve significantly lower real sample temperatures and to balance among the intertangled experimental issues in biological NRVS measurements.
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