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Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization. / Bothe, Sarah; Nowag, Jens; Klimavičius, Vytautas et al.

In: Journal of Physical Chemistry C, Vol. 122, No. 21, 31.05.2018, p. 11422-11432.

Research output: Contribution to journal › Article › peer-review

Harvard

Bothe, S, Nowag, J, Klimavičius, V, Hoffmann, M, Troitskaya, TI, Amosov, EV, Tormyshev, VM, Kirilyuk, I, Taratayko, A, Kuzhelev, A, Parkhomenko, D, Bagryanskaya, E, Gutmann, T & Buntkowsky, G 2018, 'Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization', Journal of Physical Chemistry C, vol. 122, no. 21, pp. 11422-11432. https://doi.org/10.1021/acs.jpcc.8b02570

APA

Bothe, S., Nowag, J., Klimavičius, V., Hoffmann, M., Troitskaya, T. I., Amosov, E. V., Tormyshev, V. M., Kirilyuk, I., Taratayko, A., Kuzhelev, A., Parkhomenko, D., Bagryanskaya, E., Gutmann, T., & Buntkowsky, G. (2018). Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization. Journal of Physical Chemistry C, 122(21), 11422-11432. https://doi.org/10.1021/acs.jpcc.8b02570

Vancouver

Bothe S, Nowag J, Klimavičius V, Hoffmann M, Troitskaya TI, Amosov EV et al. Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization. Journal of Physical Chemistry C. 2018 May 31;122(21):11422-11432. doi: 10.1021/acs.jpcc.8b02570

Author

Bothe, Sarah ; Nowag, Jens ; Klimavičius, Vytautas et al. / Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization. In: Journal of Physical Chemistry C. 2018 ; Vol. 122, No. 21. pp. 11422-11432.

BibTeX

@article{7a77d0c0362348ff9113eda77d9cbb59,
title = "Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization",
abstract = "Synthesis of novel trityl-nitroxyl biradicals and their performance as polarization agents in DNP-enhanced solid-state MAS NMR spectroscopy is presented. Signal enhancements in 1H, 1H → 13C CP MAS, and 13C MAS experiments obtained with these radicals dissolved in 1,1,2,2-tetrachloroethane (TCE) solution are compared with the enhancements obtained from TCE solutions of binitroxyl radicals. The signal enhancements are correlated with the distance between the radical centers of the biradicals, as determined by theoretical structure calculations. Some of the biradical TCE solutions display direct-channel resonances in 13C MAS experiments as well as indirect channel resonances induced via the proton spin reservoir. Differential scanning calorimetry reveals that only these solutions do not form any solid crystalline phases upon rapid cooling, suggesting that molecular motions needed for polarization transfer from radicals to 13C via the proton spin reservoir remain active at the experimental low temperatures of nominal 120 K. DNP magnetic field sweep enhancement profiles for selected new biradicals are presented as well. These indicate that the DNP transfer is dominated by the cross-effect mechanism.",
keywords = "TRITYL-NITROXIDE BIRADICALS, INTRACELLULAR OXYGEN PROBES, ENHANCED NMR-SPECTROSCOPY, SOLID-STATE, POLARIZING AGENTS, ABSOLUTE SENSITIVITY, HIGH-FREQUENCY, AQUEOUS-MEDIA, RADICALS, EFFICIENT",
author = "Sarah Bothe and Jens Nowag and Vytautas Klimavi{\v c}ius and Markus Hoffmann and Troitskaya, {Tatiana I.} and Amosov, {Evgenii V.} and Tormyshev, {Victor M.} and Igor Kirilyuk and Andrey Taratayko and Andrey Kuzhelev and Dmitriy Parkhomenko and Elena Bagryanskaya and Torsten Gutmann and Gerd Buntkowsky",
year = "2018",
month = may,
day = "31",
doi = "10.1021/acs.jpcc.8b02570",
language = "English",
volume = "122",
pages = "11422--11432",
journal = "Journal of Physical Chemistry C",
issn = "1932-7447",
publisher = "American Chemical Society",
number = "21",

}

RIS

TY - JOUR

T1 - Novel Biradicals for Direct Excitation Highfield Dynamic Nuclear Polarization

AU - Bothe, Sarah

AU - Nowag, Jens

AU - Klimavičius, Vytautas

AU - Hoffmann, Markus

AU - Troitskaya, Tatiana I.

AU - Amosov, Evgenii V.

AU - Tormyshev, Victor M.

AU - Kirilyuk, Igor

AU - Taratayko, Andrey

AU - Kuzhelev, Andrey

AU - Parkhomenko, Dmitriy

AU - Bagryanskaya, Elena

AU - Gutmann, Torsten

AU - Buntkowsky, Gerd

PY - 2018/5/31

Y1 - 2018/5/31

N2 - Synthesis of novel trityl-nitroxyl biradicals and their performance as polarization agents in DNP-enhanced solid-state MAS NMR spectroscopy is presented. Signal enhancements in 1H, 1H → 13C CP MAS, and 13C MAS experiments obtained with these radicals dissolved in 1,1,2,2-tetrachloroethane (TCE) solution are compared with the enhancements obtained from TCE solutions of binitroxyl radicals. The signal enhancements are correlated with the distance between the radical centers of the biradicals, as determined by theoretical structure calculations. Some of the biradical TCE solutions display direct-channel resonances in 13C MAS experiments as well as indirect channel resonances induced via the proton spin reservoir. Differential scanning calorimetry reveals that only these solutions do not form any solid crystalline phases upon rapid cooling, suggesting that molecular motions needed for polarization transfer from radicals to 13C via the proton spin reservoir remain active at the experimental low temperatures of nominal 120 K. DNP magnetic field sweep enhancement profiles for selected new biradicals are presented as well. These indicate that the DNP transfer is dominated by the cross-effect mechanism.

AB - Synthesis of novel trityl-nitroxyl biradicals and their performance as polarization agents in DNP-enhanced solid-state MAS NMR spectroscopy is presented. Signal enhancements in 1H, 1H → 13C CP MAS, and 13C MAS experiments obtained with these radicals dissolved in 1,1,2,2-tetrachloroethane (TCE) solution are compared with the enhancements obtained from TCE solutions of binitroxyl radicals. The signal enhancements are correlated with the distance between the radical centers of the biradicals, as determined by theoretical structure calculations. Some of the biradical TCE solutions display direct-channel resonances in 13C MAS experiments as well as indirect channel resonances induced via the proton spin reservoir. Differential scanning calorimetry reveals that only these solutions do not form any solid crystalline phases upon rapid cooling, suggesting that molecular motions needed for polarization transfer from radicals to 13C via the proton spin reservoir remain active at the experimental low temperatures of nominal 120 K. DNP magnetic field sweep enhancement profiles for selected new biradicals are presented as well. These indicate that the DNP transfer is dominated by the cross-effect mechanism.

KW - TRITYL-NITROXIDE BIRADICALS

KW - INTRACELLULAR OXYGEN PROBES

KW - ENHANCED NMR-SPECTROSCOPY

KW - SOLID-STATE

KW - POLARIZING AGENTS

KW - ABSOLUTE SENSITIVITY

KW - HIGH-FREQUENCY

KW - AQUEOUS-MEDIA

KW - RADICALS

KW - EFFICIENT

UR - http://www.scopus.com/inward/record.url?scp=85046662792&partnerID=8YFLogxK

U2 - 10.1021/acs.jpcc.8b02570

DO - 10.1021/acs.jpcc.8b02570

M3 - Article

AN - SCOPUS:85046662792

VL - 122

SP - 11422

EP - 11432

JO - Journal of Physical Chemistry C

JF - Journal of Physical Chemistry C

SN - 1932-7447

IS - 21

ER -

ID: 13754619