Article ID Journal Published Year Pages File Type
1246413 Talanta 2006 7 Pages PDF
Abstract

Application of capillary electrophoresis (CE) to simultaneously determine the apparent binding constants and thermodynamic parameters for six positional and structural naphthalenesulfonate derivatives with β-cyclodextrin (β-CD) is presented. The change in electrophoresis mobilities was used to assess the binding constants by non-linear regression and three different linear plots methods (named double reciprocal, x-reciprocal and y-reciprocal). The substituent group(s) attached to the naphthalene ring considerably affected the inclusion behaviors of these naphthalenesulfonate derivatives. The binding constant varies over almost one order of magnitude and a highly selective sequence is obtained between these guest model compounds. Naphthalenesulfonates with the substituent(s) at the 2-position(s) displayed stronger interaction with β-CD, and gave well compatible results by these four plot methods. While at least one substituent was substituted into the 1-position of naphthalene showed the weak interaction or no interaction with β-CD. Comparison to three linear regression methods, the non-linear regression method proves to be the most suitable for these determinations. Additionally, apparent binding constants for each structural isomer with β-CD at several temperature, and thermodynamic parameters for binding were also calculated and discussed.

Related Topics
Physical Sciences and Engineering Chemistry Analytical Chemistry
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