Factors affecting mixed-mode retention properties of cation-exchange stationary phases.

J Chromatogr A

University of Marburg, Faculty of Chemistry, Hans-Meerwein-Str. 4, 35043 Marburg, Germany. Electronic address:

Published: April 2023

Cation-exchange stationary phases were characterized in different chromatographic modes (HILIC, RPLC, IC) and applied to the separation of non-charged hydrophobic and hydrophilic analytes. The set of columns under investigation included both commercially available cation-exchangers and self-prepared PS/DVB-based columns, the latter consisting of adjustable amounts of carboxylic and sulfonic acid functional groups. The influence of cation-exchange site and polymer substrate on the multimodal properties of cation-exchangers was identified using selectivity parameters, polymer imaging and excess adsorption isotherms. Introducing weakly acidic cation-exchange functional groups to the unmodified PS/DVB-substrate effectively reduced hydrophobic interactions, whilst a low degree of sulfonation (0.09 to 0.27% w/w sulphur) mainly influenced electrostatic interactions. Silica substrate was found to be another important factor for inducing hydrophilic interactions. The presented results demonstrate that cation-exchange resins are suitable for mixed-mode applications and offer versatile selectivity.

Download full-text PDF

Source
http://dx.doi.org/10.1016/j.chroma.2023.463934DOI Listing

Publication Analysis

Top Keywords

cation-exchange stationary
8
stationary phases
8
functional groups
8
cation-exchange
5
factors mixed-mode
4
mixed-mode retention
4
retention properties
4
properties cation-exchange
4
phases cation-exchange
4
phases characterized
4

Similar Publications

Mixed-mode separation of antisense oligonucleotides using a single column with complementary anion-exchange and hydrophobic interaction chromatography approaches.

J Chromatogr A

January 2025

Genetics Guided Dementia Discovery (G2D2), Eisai, Inc. 35 Cambridge Park Drive, Suite 200, Cambridge, MA, 02140, USA.

The current study investigates the use of mixed-mode chromatography as a combination of anion-exchange (AEX) and hydrophobic interaction chromatography (HIC) for the analysis and purification of single-stranded antisense oligonucleotides with stereo-controlled phosphorothioate inter- nucleotide linkages. Initially a Scherzo-SS-C18 trimodal stationary phase with reversed-phase/AEX/ cation-exchange (CEX) functionalities is systematically evaluated to reveal the presence of U-shaped retention composed of two retention modes namely AEX and HIC, where the latter was also observed on related trimodal Scherzo SM and SW analogues. For the first time, retention and separation of deprotected oligonucleotides was described on a single mixed-mode column using a combination of AEX and HIC.

View Article and Find Full Text PDF

Separation of phenylpropionic acids both by strong anion exchange stationary phase and strong cation exchange stationary phase in supercritical fluid chromatography, using the same additive.

J Chromatogr A

January 2025

Ministry of Education, Engineering Research Center of Pharmaceutical Process Chemistry, School of Pharmacy, East China University of Science and Technology, Shanghai 200237, PR China; Key Lab of Separation Science for Analytical Chemistry, Key Lab of Natural Medicine, Dalian Institute of Chemical Physics, Chinese Academy of Sciences, Dalian, Liaoning Province 116023, PR China.

This study demonstrates the expanded application of ion-exchange stationary phases (including strong cation exchange, SCX and strong anion exchange, SAX) in supercritical fluid chromatography (SFC), and more importantly, provides a deeper understanding of the retention mechanisms of these two stationary phases when using the same acidic additive. Phenylpropionic acid compounds (belonging to phenolic acids) were selected as probes. On the SCX column, the π-π and polar interactions originating from the bonded benzenesulfonic acid groups were important foundations for prolonging the retention time of solutes, but they were also the main reason for solutes' tailing profiles.

View Article and Find Full Text PDF

Using poly(styrene-divinylbenzene) microspheres as stationary phase matrix and mercaptosuccinic acid as a modifier, a new weak cation exchange resin was synthesized by thiol click reaction. The conditions for thiol-chlorine click reaction and thiol-alkene click reaction were optimized. The surface morphology and chemical composition of the modified microspheres were characterized by scanning electron microscopy, Fourier-transform infrared spectroscopy, and an elemental analyzer.

View Article and Find Full Text PDF
Article Synopsis
  • The study investigates the matrix effect of ammonium ions on the behavior of lithium, sodium, and tris ions in ion chromatography, revealing that higher ammonium concentrations affect ion retention times.
  • The experimental setup varied eluent concentrations, column temperatures, and injected volumes to analyze how these factors influence ion resolution.
  • The research indicates that using a well-optimized ammonium hydroxide matrix can enhance the separation efficiency of inorganic and organic cations, particularly under specific conditions involving methanesulfonic acid eluent and precise temperatures.
View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!