Azaadamantyl nitroxide spin label: complexation with β-cyclodextrin and electron spin relaxation

Sandra S. Eaton, Andrzej Rajca, Zhimin Yang, Gareth R. Eaton

Research output: Contribution to journalArticle

1 Citation (Scopus)

Abstract

An iodoacetamide azaadamantyl spin label was studied in fluid solution and in 9:1 trehalose:sucrose glass. In 9:1 toluene:CH2Cl2 solution at 293 K, the isotropic nitrogen hyperfine coupling is 19.2 G, T1 is 0.37 µs and T2 is 0.30–0.35 µs. Between about 80 and 150 K 1/Tm in 9:1 trehalose:sucrose is approximately independent of temperature demonstrating that the absence of methyl groups decreases 1/Tm relative to that which is observed in spin labels with methyl groups on the alpha carbons. Spin lattice relaxation rates between about 80 and 293 K in 9:1 trehalose:sucrose are similar to those observed for other nitroxide spin labels, consistent with the expectation that relaxation is dominated by Raman and local mode processes. Although complexation of the azaadamantyl spin label with β-cyclodextrin slows tumbling in aqueous solution by about a factor of 10, it has little impact on 1/T1 or 1/Tm in 9:1 trehalose:sucrose between 80 and 293 K.

Original languageEnglish (US)
Pages (from-to)319-326
Number of pages8
JournalFree Radical Research
Volume52
Issue number3
DOIs
StatePublished - Mar 4 2018

Fingerprint

Spin Labels
Trehalose
Cyclodextrins
Complexation
Sucrose
Electrons
Iodoacetamide
Barreling
Spin-lattice relaxation
Toluene
Glass
Nitrogen
Carbon
Temperature
Fluids

Keywords

  • Double electron resonance
  • spin echo dephasing
  • spin lattice relaxation

ASJC Scopus subject areas

  • Biochemistry

Cite this

Azaadamantyl nitroxide spin label : complexation with β-cyclodextrin and electron spin relaxation. / Eaton, Sandra S.; Rajca, Andrzej; Yang, Zhimin; Eaton, Gareth R.

In: Free Radical Research, Vol. 52, No. 3, 04.03.2018, p. 319-326.

Research output: Contribution to journalArticle

Eaton, Sandra S. ; Rajca, Andrzej ; Yang, Zhimin ; Eaton, Gareth R. / Azaadamantyl nitroxide spin label : complexation with β-cyclodextrin and electron spin relaxation. In: Free Radical Research. 2018 ; Vol. 52, No. 3. pp. 319-326.
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