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Updated: Jun 28, 2026

Elucidating the Metabolism of 2,4-Dibromophenol in Plants
Published on: February 10, 2023
Thermodynamic approach for studying both the retention and complexation mechanisms with
François Darrouzain1, Myriam Matoga, Eric Cavalli
1Equipe des Sciences Séparatives et Biopharmaceutiques (2SB), Laboratoire de Chimie Analytique, Faculté de Médecine et de Pharmacie, Place Saint-Jacques, 25030 Besançon Cedex, France.
Abstract:
The retention and complexation mechanisms of a herbicide series were studied from a chromatographic approach using a novel column called "Nautilus((R))". The effects of water fraction and the hydroxy-propyl-beta-cyclodextrin (HP-beta-CD) concentration in the mobile phase were analysed in relation to the column temperature. Two retention models of phenoxy-propionic acid (PPA) derivatives were investigated. It was shown that the retention mechanism was led by free PPA herbicide for low HP-beta-CD concentrations and by the PPA/HP-beta-CD complex for the highest ones. In addition, an enthalpy-entropy compensation study revealed that both the solute retention and complexation mechanisms were independent of the number of chlorine atoms in the structure. Also the thermodynamic results showed that (1) the retention process depended on the water fraction (X) in the mobile phase and (2) the PPA/HP-beta-CD complexation mechanism was shown to be entropically controlled.
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