title: Gradient retention prediction of acid-base analytes in reversed phase liquid chromatography: a simplified approach for acetonitrile-water mobile phases.
abstract: In previous work, a two-parameter model to predict chromatographic retention of ionizable analytes in gradient mode was proposed. However, the procedure required some previous experimental work to get a suitable description of the pKa change with the mobile phase composition. In the present study this previous experimental work has been simplified. The analyte pKa values have been calculated through equations whose coefficients vary depending on their functional group. Forced by this new approach, other simplifications regarding the retention of the totally neutral and totally ionized species also had to be performed. After the simplifications were applied, new prediction values were obtained and compared with the previously acquired experimental data. The simplified model gave pretty good predictions while saving a significant amount of time and resources.
authors.affiliation: Departament de Química Analítica and Institut de Biomedicina (IBUB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona Spain.
authors.forename: Axel
authors.initials: A
authors.lastname: Andrés
authors.affiliation: Departament de Química Analítica and Institut de Biomedicina (IBUB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona Spain.
authors.forename: Martí
authors.initials: M
authors.lastname: Rosés
authors.affiliation: Departament de Química Analítica and Institut de Biomedicina (IBUB), Universitat de Barcelona, Martí i Franquès 1-11, 08028 Barcelona Spain. Electronic address: e.bosch@ub.edu.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Bosch
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000468:Alkalies; D002851:Chromatography, High Pressure Liquid; D056148:Chromatography, Reverse-Phase / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000468:Alkalies; D014867:Water; C032159:acetonitrile
keywords: Gradient elution; Ionizable analytes; RP-HPLC; Retention models; pK(a) calculation