Inclusion complexes of cyclodextrins with nitroxide-based spin probes in aqueous solutions

Gabriela Ionita, Agneta Caragheorgheopol, Horia Caldararu, Leonie Jones, Victor Chechik

Research output: Contribution to journalArticlepeer-review

Abstract

Formation of inclusion complexes between several cyclodextrin derivatives and TEMPO and DOXYL-based spin probes was studied by EPR spectroscopy. Competition between alkyl chains and nitroxide functionalities for cyclodextrin cavities leads to different types of complexation. Long alkyl chains in amphiphilic spin probes interact preferentially with cyclodextrins, and TEMPO units in such molecules are unaffected by complexation. DOXYL-type spin probes however form stronger complexes with cyclodextrins; this complexation changes hyper. ne splitting and tumbling rate of the nitroxide group. Comparison of EPR spectra of free cyclodextrin and cyclodextrin-based polymeric nanocapsules made it possible to assess the tumbling of the spin probe inside the cyclodextrin units without the contribution of the tumbling of the whole complex.

Original languageEnglish
Pages (from-to)598-602
Number of pages5
JournalOrganic and Biomolecular Chemistry
Volume7
Issue number3
DOIs
Publication statusPublished - 2009

Keywords

  • BETA-CYCLODEXTRIN
  • LABELED CYCLODEXTRINS
  • AMPHIPHILIC CYCLODEXTRINS
  • BIMODAL INCLUSION
  • RESONANCE
  • RADICALS
  • WATER
  • SUPEROXIDE
  • MODEL

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