Modeling indirectly detected analyte peaks in ion-pair reversed-phase chromatography.

Autor: Leśko M; Department of Engineering and Chemical Sciences, Karlstad University SE-651 88 Karlstad, Sweden., Szabados G; Department of Engineering and Chemical Sciences, Karlstad University SE-651 88 Karlstad, Sweden., Fornstedt T; Department of Engineering and Chemical Sciences, Karlstad University SE-651 88 Karlstad, Sweden. Electronic address: Torgny.Fornstedt@kau.se., Samuelsson J; Department of Engineering and Chemical Sciences, Karlstad University SE-651 88 Karlstad, Sweden. Electronic address: Jorgen.Samuelsson@kau.se.
Jazyk: angličtina
Zdroj: Journal of chromatography. A [J Chromatogr A] 2024 Nov 23; Vol. 1740, pp. 465550. Date of Electronic Publication: 2024 Nov 23.
DOI: 10.1016/j.chroma.2024.465550
Abstrakt: In indirect detection, sample components lacking detectable properties are detected by adding a detectable component to the eluent, a so-called probe that interacts with the analytes to be detected. This study focuses on modeling indirect detection in two principally different cases. In case (1), the analyte component has the same charge as the probe component, so the probe acts as a co-ion of the analyte. In case (2), the analyte component has the opposite charge to the probe, so the probe acts as a counter-ion of the analyte. In the co-ion case (1), the analytes are alkyl sulfonates, and a competitive bi-Langmuir isotherm model was used. In the counter-ion case (2), the analytes are amines, and a modified bi-Langmuir isotherm model, incorporating ion-pairing on the stationary phase surface, was derived and applied for simulating the elution profiles. The chromatographic system comprised an XBridge Phenyl column as the stationary phase and an acetonitrile/phosphate buffer mixture with varying concentrations of sodium 2-naphthalenesulfonate as the eluent. In both cases, the detectable probe component was sodium 2-naphthalenesulfonate. The applied isotherm models successfully predicted system peaks with high agreement in both model cases, with calculated relative errors in retention times typically below 4.72 % and often below 1 %. The models were employed to predict the sensitivity of analytical methods, demonstrating excellent agreement between experimental and calculated sensitivities. These findings confirm the validity of the new adsorption isotherm model under these experimental conditions.
Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper.
(Copyright © 2024. Published by Elsevier B.V.)
Databáze: MEDLINE
Externí odkaz: