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Probing the general time scale question of boronic acid binding with sugars in aqueous solution at physiological pH.

ABSTRACT: The boronic acid group is widely used in chemosensor design due to its ability to reversibly bind diol-containing compounds. The thermodynamic properties of the boronic acid-diol binding process have been investigated extensively. However, there are few studies of the kinetic properties of such binding processes. In this report, stopped-flow method was used for the first time to study the kinetic properties of the binding between three model arylboronic acids, 4-, 5-, and 8-isoquinolinylboronic acids, and various sugars. With all the boronic acid-diol pairs examined, reactions were complete within seconds. The k(on) values with various sugars follow the order of D-fructose>D-tagatose>D-mannose>D-glucose. This trend tracks the thermodynamic binding affinities for these sugars and demonstrates that the 'on' rate is the key factor determining the binding constant.

SUBMITTER: Ni N

PROVIDER: S-EPMC3355949 | biostudies-literature | 2012 May

REPOSITORIES: biostudies-literature

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Probing the general time scale question of boronic acid binding with sugars in aqueous solution at physiological pH.

Ni Nanting N Laughlin Sarah S Wang Yingji Y Feng You Y Zheng Yujun Y Wang Binghe B

Bioorganic & medicinal chemistry 20120310 9

The boronic acid group is widely used in chemosensor design due to its ability to reversibly bind diol-containing compounds. The thermodynamic properties of the boronic acid-diol binding process have been investigated extensively. However, there are few studies of the kinetic properties of such binding processes. In this report, stopped-flow method was used for the first time to study the kinetic properties of the binding between three model arylboronic acids, 4-, 5-, and 8-isoquinolinylboronic ...[more]

PMID: 22464680

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