Determination of Binding Strengths of Host-Guest Complexes in Deep Eutectic Solvents Using Spin Probe Methodology

Andrea Cantelli; Paola Franchi; Elisabetta Mezzina; Marco Lucarini

doi:10.1002/cphc.202001007

Determination of Binding Strengths of Host-Guest Complexes in Deep Eutectic Solvents Using Spin Probe Methodology

Chemphyschem. 2021 Mar 17;22(6):517-521. doi: 10.1002/cphc.202001007. Epub 2021 Feb 11.

Authors

Andrea Cantelli¹, Paola Franchi¹, Elisabetta Mezzina¹, Marco Lucarini¹

Affiliation

¹ Department of Chemistry "G. Ciamician", University of Bologna, Via San Giacomo 11, Bologna.

PMID: 33524192
DOI: 10.1002/cphc.202001007

Abstract

Electron paramagnetic resonance (EPR) and spin probe methodologies have been employed to study the complexation properties of cyclodextrins (CDs) and cucurbit[n]urils (CB[n]s) in the deep eutectic solvent (DES) choline chloride-urea. In the presence of γ-CD an affinity constant very similar to that measured in water was measured in DES with benzyl-tert-butyl nitroxide (BTBN). With β-CD, complexation of BTBN is significantly depressed, although still maintained. Complexation of TEMPO radical probe by CB[7] or CB[8] was instead almost entirely cancelled in DES. In addition, this methodology enabled for the first time to measure the single rate constants for the association and dissociation processes with CDs in DES.

Keywords: Cyclodextrins; deep eutectic solvents; electron paramagnetic resonance; host-guest chemistry; spin probes.

Publication types

Research Support, Non-U.S. Gov't

Abstract

Publication types

Grants and funding