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oai:recercat.cat:2445/1619862025-12-04T19:36:52Zcom_2072_1057col_2072_478813col_2072_478917

urn:hdl:2445/161986 Feasibility of the estimation of octanol-water distribution coefficients of acidic drugs by microemulsion electrokinetic chromatography Fernández-Pumarega, Alejandro Amézqueta, Susana Fuguet i Jordà, Elisabet Rosés Pascual, Martí Electroforesi capil·lar Lipofília Capillary electrophoresis Lipophilicity Previous studies have shown that a microemulsion electrokinetic chromatography (MEEKC) system can estimate the logarithm of the octanol-water partition coefficient (log Po/w) of neutral solutes. In the present work, the applicability of the method to partially and fully ionized acids has been evaluated. Naproxen, a monoprotic acid, has been used as test solute. The retention factor (k) of this compound has been measured in MEEKC at several values of pH and the retention factor-pH profile has been established. As log Po/w correlates with log kMEEKC for neutral compounds, this correlation has been used to estimate the logarithm of the octanol-water partition coefficient of the neutral (log Po/w(HA)), and the fully ionized (log P o/w(A-)) forms of naproxen. Then, the logarithm of the octanol-water distribution coefficient (log Do/w) of the partially ionized form of the acid has been estimated. The comparison of the estimated values with the ones obtained experimentally using the classical procedures, such as the shake-flask method, shows differences under 0.4 log Do/w units either if the acid is partially ionized or in its neutral form in the most part of the pH range. However, the method overestimates the log Do/w of the highly (>99.5 %) or fully ionized form of naproxen 2020-05-22T09:02:53Z 2020-05-22T09:02:53Z 2018-03-25 2020-05-22T09:02:53Z info:eu-repo/semantics/article info:eu-repo/semantics/publishedVersion Reproducció del document publicat a: https://doi.org/10.5599/admet.6.1.510 ADMET & DMPK, 2018, vol. 6, num. 1, p. 55-60 https://doi.org/10.5599/admet.6.1.510 cc-by (c) Fernández-Pumarega, Alejandro et al., 2018 http://creativecommons.org/licenses/by/3.0/es info:eu-repo/semantics/openAccess IAPC Publishing Articles publicats en revistes (Enginyeria Química i Química Analítica)