CaltechAUTHORS
  A Caltech Library Service

Extrathermodynamic relations in the binding of charged and neutral substrates to sulfobutylether-β-CDs (SBE-β-CDs) and a 2-hydroxypropyl-β-CD (HP-β-CD)

Zia, V. and Vander Velde, D. and Stella, V. J. (2014) Extrathermodynamic relations in the binding of charged and neutral substrates to sulfobutylether-β-CDs (SBE-β-CDs) and a 2-hydroxypropyl-β-CD (HP-β-CD). Journal of Inclusion Phenomena and Macrocyclic Chemistry, 79 (3-4). pp. 503-512. ISSN 1388-3127. http://resolver.caltech.edu/CaltechAUTHORS:20140818-090433954

Full text is not posted in this repository. Consult Related URLs below.

Use this Persistent URL to link to this item: http://resolver.caltech.edu/CaltechAUTHORS:20140818-090433954

Abstract

The thermodynamics of binding of various neutral, cationic and anionic substrates to β-cyclodextrin, a hydroxylpropyl-β-cyclodextrin (HP_(4M)-β-CD) and three sulfobutyl-β-cyclodextrins with varying degrees of total substitution (SBE_(1M)-β-CD, SBE_(7M)-β-CD, and SBE_(12M)-β-CD) were determined by estimating binding constants, using a UV spectrophotometric technique, and temperature variation. linear free energy relation (LFER) plots and enthalpy–entropy Compensation (EEC) plots provided insight into the mechanisms of complexation as did carbon T_1 relaxation times using NMR. LFER plots for charged molecules with HP_(4M)-β-CD deviate from the neutral substrates suggesting differences in interaction modes. LFER plots for SBE_(7M)-β-CD show that cationic substrates surprisingly fall within the same linear relationship for neutral substrates while anionic substrates deviate. The EEC plots for HP_(4M)-β-CD show the largest loss of motion and degree of desolvation upon complexation. The interaction with SBE_(1M)-β-CD was similar to that for β-CD. SBE_(7M)-β-CD, and SBE_(12M)-β-CD EEC plots are similar with the least loss of motion upon complex formation, suggesting a more organized and less flexible structure. This is supported by the T_1 relaxation times for SBE_(1M)-β-CD, SBE_(7M)-β-CD, and SBE_(12M)-β-CD, which show a critical distance at which the mobility of the side chain is reduced to form an extended cavity. No such evidence was seen with HP_(4M)-β-CD, although the effect of varying of hydroxypropyl substitution was not studied.


Item Type:Article
Related URLs:
URLURL TypeDescription
http://link.springer.com/article/10.1007/s10847-013-0374-2PublisherArticle
http://dx.doi.org/10.1007/s10847-013-0374-2DOIArticle
http://rdcu.be/tvTKPublisherFree ReadCube access
Additional Information:© 2013 Springer Science+Business Media Dordrecht. Received: 7 October 2013. Accepted: 25 November 2013. Published online: 3 December 2013.
Subject Keywords:Cyclodextrin, Complexation, Thermodynamics, Inclusion, complexes, Hydroxypropyl-b-cyclodextrin, Sulfobutyl-bcyclodextrin, Temperature effects, Binding
Record Number:CaltechAUTHORS:20140818-090433954
Persistent URL:http://resolver.caltech.edu/CaltechAUTHORS:20140818-090433954
Official Citation:Zia, V., Vander Velde, D. & Stella, V.J. J Incl Phenom Macrocycl Chem (2014) 79: 503. doi:10.1007/s10847-013-0374-2
Usage Policy:No commercial reproduction, distribution, display or performance rights in this work are provided.
ID Code:48641
Collection:CaltechAUTHORS
Deposited By: Ruth Sustaita
Deposited On:19 Aug 2014 22:13
Last Modified:16 Jun 2017 16:32

Repository Staff Only: item control page