Identification of Beryllium Fluoride Complexes in Mechanically Distorted Gels Using Quadrupolar Split 9Be NMR Spectra Resolved with Solution-State Selective Cross-Polarization Full article
Journal |
PCCP: Physical Chemistry Chemical Physics
ISSN: 1463-9076 , E-ISSN: 1463-9084 |
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Output data | Year: 2021, Volume: 23, Number: 31, Pages: 16932-16941 Pages count : 10 DOI: 10.1039/d1cp02515e | ||||||
Tags | NUCLEAR-MAGNETIC-RESONANCE; BERYLLOFLUORIDE COMPLEXES; COORDINATION CHEMISTRY; AQUEOUS-SOLUTION; GAMMA-PHOSPHATE; SPECTROSCOPY; ALIGNMENT; BICELLES; ALUMINUM; ANALOGS | ||||||
Authors |
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Affiliations |
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Funding (3)
1 | Ministry of Science and Higher Education of the Russian Federation | 0239-2021-0009 |
2 | Leverhulme Trust | RPG-2020-066 |
3 | Australian Research Council | DP190100510 |
Abstract:
The uniformly anisotropic media afforded by hydrogels are being increasingly exploited in analytical (structure elucidation) nuclear magnetic resonance (NMR) spectroscopy, and in studies of mechanosensitive biophysical and biochemical properties of living cells. The 9Be NMR parameters of beryllium fluoride complexes formed in aqueous solutions are sensitive markers of the anisotropic molecular environments produced by gelatin gels. The electric quadrupole moment of the 9Be nucleus (spin I = 3/2) interacts with the electric field gradient tensor in a stretched (or compressed) gel, giving rise to the splitting of peaks in 9Be NMR spectra. These are in addition to those produced by scalar coupling to the 19F nuclei. Thus, an equilibrium mixture of beryllofluoride complexes (BeF2, BeF3−, and BeF42−) in mechanically distorted gels generates an envelope of overlapping 9Be NMR multiplets. In the present work, the multiplets were dissected apart by using selective excitation of 9Be–19F cross-polarization; and the spectral components were quantified with multi-parameter line-shape decomposition, coupled with SpinDynamica simulations. The effects of gel density and Bloom number (a measure of gelatin-gel rigidity under standard conditions of sample preparation) on residual quadrupolar splittings were examined. Cross-polarization experiments revealed a bimodal distribution of residual quadrupolar coupling constants (RQC) of the BeF3− complexes. The average RQC of the dominant BeF3− population was ∼3 times larger than that of BeF42−. The secondary BeF3− population existed in a tetrahedral configuration. It was attributed to BeF3− complexes associated with negatively charged –COO− groups of the denatured collagen matrix.
Cite:
Romanenko K.
, Elliott S.J.
, Shubin A.A.
, Kuchel P.W.
Identification of Beryllium Fluoride Complexes in Mechanically Distorted Gels Using Quadrupolar Split 9Be NMR Spectra Resolved with Solution-State Selective Cross-Polarization
PCCP: Physical Chemistry Chemical Physics. 2021. V.23. N31. P.16932-16941. DOI: 10.1039/d1cp02515e WOS Scopus РИНЦ AN OpenAlex
Identification of Beryllium Fluoride Complexes in Mechanically Distorted Gels Using Quadrupolar Split 9Be NMR Spectra Resolved with Solution-State Selective Cross-Polarization
PCCP: Physical Chemistry Chemical Physics. 2021. V.23. N31. P.16932-16941. DOI: 10.1039/d1cp02515e WOS Scopus РИНЦ AN OpenAlex
Dates:
Submitted: | Jun 5, 2021 |
Accepted: | Jul 16, 2021 |
Published online: | Jul 17, 2021 |
Published print: | Aug 21, 2021 |
Identifiers:
Web of science: | WOS:000679993800001 |
Scopus: | 2-s2.0-85112718138 |
Elibrary: | 46977466 |
Chemical Abstracts: | 2021:1577944 |
OpenAlex: | W3184308056 |