title: Facilitated ion transfer of protonated primary organic amines studied by square wave voltammetry and chronoamperometry.
abstract: The transfer of the protonated forms of heptylamine, octylamine, decylamine, procaine and procainamide facilitated by dibenzo-18-crown-6 from water to a solvent polymeric membrane has been investigated by using cyclic square wave voltammetry. The experimental voltammograms obtained are in good agreement with theoretical predictions. The values of the standard ion transfer potential, complexation constant and diffusion coefficient in water have been obtained from these experiments, and have been used to draw some conclusions about the lipophilicity of these species and the relative stability of the organic ammonium complexes with dibenzo-18-crown-6. The results have been compared with those provided by linear sweep voltammetry. Calibration graphs were obtained with both techniques. An interesting chronoamperometric method for the determination of the diffusion coefficient of the target ion in the membrane has been developed and applied to all these protonated amines.
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de Murcia, Murcia 30100, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Torralba
authors.affiliation: Departamento de Química Analítica, Facultad de Química, Universidad de Murcia, Murcia 30100, Spain.
authors.forename: J A
authors.initials: JA
authors.lastname: Ortuño
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de Murcia, Murcia 30100, Spain. Electronic address: amolina@um.es.
authors.forename: A
authors.initials: A
authors.lastname: Molina
authors.affiliation: Departamento de Química Física, Facultad de Química, Universidad de Murcia, Murcia 30100, Spain.
authors.forename: C
authors.initials: C
authors.lastname: Serna
authors.affiliation: Department of Chemistry, Faculty of Sciences, Ferdowsi University of Mashhad, Mashhad, Iran.
authors.forename: F
authors.initials: F
authors.lastname: Karimian
keywords: Cyclic square wave voltammetry; Facilitated ion transfer; Liquid membranes; Protonated primary organic amines