Universität zu Köln

Niether, Doreen ORCID: 0000-0002-8496-4215, Kawaguchi, Tsubasa, Hovancova, Jana ORCID: 0000-0001-9101-2119, Eguchi, Kazuya, Dhont, Jan K. G., Kita, Rio ORCID: 0000-0002-9683-5840 and Wiegand, Simone ORCID: 0000-0001-6333-1956 (2017). Role of Hydrogen Bonding of Cyclodextrin-Drug Complexes Probed by Thermodiffusion. Langmuir, 33 (34). S. 8483 - 8493. WASHINGTON: AMER CHEMICAL SOC. ISSN 0743-7463

Full text not available from this repository.

Abstract

Temperature gradient-induced migration of biomolecules, known as thermophoresis or thermodiffusion, changes upon ligand binding. In recent years, this effect has been used to determine protein ligand binding constants. The mechanism through which thermodiffusive properties change when complexes are formed, however, is not understood. An important contribution to thermodiffusive properties originates from the thermal response of hydrogen bonds. Because there is a considerable difference between the degree of solvation of the protein ligand complex and its isolated components, ligand-binding is accompanied by a significant change in hydration. The aim of the present work is therefore to investigate the role played by hydrogen bonding on the change in thermodiffusive behavior upon ligand-binding. As a model system, we use cyclodextrins (CDs) and acetylsalicylic acid (ASA), where quite a significant change in hydration is expected and where no conformational changes occur when a CD/ASA complex is formed in aqueous solution. Thermophoresis was investigated in the temperature range of 10-50 degrees C by infrared thermal diffusion forced Rayleigh scattering. Nuclear magnetic resonance measurements were performed at 25 degrees C to obtain information about the structure of the complexes. All CD/ASA complexes show a stronger affinity toward regions of lower temperature compared to the free CDs. We found that the temperature sensitivity of thermophoresis correlates with the 1-octanol/water partition coefficient. This observation not only establishes the relation between thermodiffusion and degree of hydrogen bonding but also opens the possibility to relate thermodiffusive properties of complexes to their partition coefficient, which cannot be determined otherwise. This concept is especially interesting for protein ligand complexes where the protein undergoes a conformational change, different from the CD/ASA complexes, giving rise to additional changes in their hydrophilicity.

Item Type:	Journal Article
Creators:	Creators Email ORCID ORCID Put Code Niether, Doreen UNSPECIFIED orcid.org/0000-0002-8496-4215 UNSPECIFIED Kawaguchi, Tsubasa UNSPECIFIED UNSPECIFIED UNSPECIFIED Hovancova, Jana UNSPECIFIED orcid.org/0000-0001-9101-2119 UNSPECIFIED Eguchi, Kazuya UNSPECIFIED UNSPECIFIED UNSPECIFIED Dhont, Jan K. G. UNSPECIFIED UNSPECIFIED UNSPECIFIED Kita, Rio UNSPECIFIED orcid.org/0000-0002-9683-5840 UNSPECIFIED Wiegand, Simone UNSPECIFIED orcid.org/0000-0001-6333-1956 UNSPECIFIED
URN:	urn:nbn:de:hbz:38-221639
DOI:	10.1021/acs.langmuir.7b02313
Journal or Publication Title:	Langmuir
Volume:	33
Number:	34
Page Range:	S. 8483 - 8493
Date:	2017
Publisher:	AMER CHEMICAL SOC
Place of Publication:	WASHINGTON
ISSN:	0743-7463
Language:	English
Faculty:	Faculty of Mathematics and Natural Sciences
Divisions:	Faculty of Mathematics and Natural Sciences > Department of Chemistry > Institute of Physical Chemistry
Subjects:	no entry
Uncontrolled Keywords:	Keywords Language THERMAL-DIFFUSION; BETA-CYCLODEXTRIN; SORET COEFFICIENT; LIQUID-MIXTURES; CALORIMETRIC TITRATION; INCLUSION COMPLEXATION; TEMPERATURE-DEPENDENCE; MOLECULAR RECOGNITION; CIRCULAR-DICHROISM; QUANTUM DOTS Multiple languages Chemistry, Multidisciplinary; Chemistry, Physical; Materials Science, Multidisciplinary Multiple languages
Refereed:	Yes
URI:	http://kups.ub.uni-koeln.de/id/eprint/22163