CHROMATOGRAPHY, Vol. 27 (2006), No. 2, pp. 57-62
Original
Enthalpy−entropy compensation of halogenated benzylamines in reversed−phase liquid chromatography
Masato Kazusaki＊ and Toshikazu Yamaguchi
Analysis Laboratories, Group 1, Technology Research and Development Center
Dainippon Sumitomo Pharma Co., Ltd.
1−5−51 Ebie, Fukushima−ku, Osaka, 553−0001, Japan
Abstract:
Retention behavior of halogenated benzylamines on an ODS stationary phase was studied using phosphate buffer (20 mM, pH2.0) / acetonitrile
(95/5, v/v, %) as a mobile phase. The thermodynamic properties for the transfer of halogenated benzylamines from the mobile phase to
the stationary phase were evaluated for understanding on the retention mechanism in the reversed−phase high−performance liquid chromatography.
The data were analyzed to sufficiently confirm the possibility of enthalpy−entropy compensation (EEC). The EEC indicates that enthalpic
gain for retention is canceled out to one half by the entropic loss, and that entropy−driven retention could take place without enthalpic
contribution.
Keywords:
desolvation, enthalpy−entropy compensation, halogenated benzylamine, retention behavior, van’t Hoff plot.
