Original scientific paper

Thermodynamic study of the transfer of acetanilide and phenacetin from water to different organic solvents

YOLIMA BAENA
JORGE A. PINZÓN
HELBER J. BARBOSA
FLMING MARTÍNEZ

Abstract

The molar (KCo/w) and rational (KXo/w) partition coefficients in the octanol/buffer, i-propyl myristate/buffer, chloroform/buffer, and cyclohexane/buffer systems were determined for acetanilide and phenacetin at 25.0, 30.0, 35.0, and 40.0 °C. In all cases except for cyclohexane, the KCo/w and KXo/w values were greater than unity. This demonstrates that these two drugs have predominantly lipophilic behavior. Gibbs and van't Hoff thermodynamic analyses have revealed that the transfer of these drugs from water to organic solvents is spontaneous and that it is mainly driven enthalpically for i-propyl myristate and chloroform, and entropy-driven for octanol and cyclohexane.

Keywords

acetanilide; phenacetin; partition coefficient; thermodynamics

Hrčak ID:

16757

URI

https://hrcak.srce.hr/16757

Publication date:

1.6.2005.

Article data in other languages: croatian

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