Abstract
Electrostatic ion chromatography (EIC) using a zwitterionic stationary phase (formed by coating a C 18 material with a hydrophobic zwitterionic surfactant) was studied with a mobile phase comprising an aqueous solution of histidine at the pH of its isoelectric point, together with non-suppressed conductometric detection. Anions and cations were found to be eluted as separate peaks, unlike the elution behaviour observed on the same system when pure water was used as mobile phase. An explanation was suggested in terms of protonation equilibria of the overall uncharged histidine to form small amounts of histidine cations and anions in the mobile phase which could act as counterions for analyte anions and cations. This suggestion was supported by measured pH changes occurring in the bands of eluted analyte anions (a decreased pH compared to the mobile phase) and cations (an increased pH compared to the mobile phase). The analytical potential of this type of EIC is discussed.
Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
