Non-covalent interactions evidenced by EPR spectroscopy in cyclodextrin complexes

Abstract

In this review are summarized studies, performed by researchers from the “Ilie Murgulescu” Institute of Physical Chemistry, involving electron paramagnetic resonance spectroscopy on non-covalent interactions. The review examines interactions between paramagnetic hosts and diamagnetic guests, diamagnetic hosts and paramagnetic guests, diamagnetic hosts and dual paramagnetic-fluorescent guests, interactions that accompany the formation of gel systems and interactions of fatty acid-like spin probes with proteins.

Physicochemical Changes of Alginate and Polyacrylate Mixture Induced by Interactions of the Appended Units

“…The relevant EPR parameters that are sensitive to the host–guest systems that involve complexation of nitroxides with cyclodextrins are N hyperfine coupling constant (a N ) and rotational correlational time ( τ ). [ 34,35 ] In solution, the changes in dynamic of Alg‐T and AlgCD‐T induced by the presence of NaPA and alkyl derivatives of NaPA are not significant at 293 K. In previous studies, it was noticed that the EPR spectra of TEMPO radicals recorded at lower temperatures can be useful to prove the inclusion in cyclodextrin cavities. [ 9,36,37 ] Therefore, the EPR spectra of Alg‐T, AlgCD‐T in the absence and in the presence of NaPA and its derivatives have been recorded at 150 K. The corresponding gels formed in the presence of CaCl 2 have been also recorded at 150 K. The spectra for these gels are presented in Figure .…”