Polyoxyethylene as the Stationary Phase in Ion Chromatography

Abstract

The present article reviews the use of polyethylene glycol (PEG) or polyoxyethylene (POE) as the stationary phase for the separation of inorganic anions in ion chromatography and discusses about the retention mechanisms involved in the separation of anions on the novel stationary phases. PEG permanently coated on a hydrophobic stationary phase retained anions in the partition mode and allowed us to use high-concentration eluents because the retention of anions increased with increasing eluent concentration for most of the eluents. This situation was convenient to determine trace anions contained in seawater samples without any disturbance due to matrices. Chemically bonded POE stationary phases retained not only anions but also cations. Anions were retained in the ion-exchange mode, although POE chains possess no ion exchange sites. The retention behavior suggested that eluent cations could be trapped among multiple POE chains via ion-dipole interaction, and that the trapped cations worked as the anion-exchange sites. Anions could be separated using crown ether, i.e., cyclic POE, as the eluent additive with a hydrophobic stationary phase, where analyte anions were retained via electrostatic interaction with the eluent cation trapped on the crown ether.

Separation of Inorganic Anions on a Chemically Bonded 18-Crown-6 Ether Stationary Phase in Capillary Ion Chromatography

“…[8][9][10] Chemically bonded poly(oxyethylene) (POE) stationary phases could also separate anions in the ion-exchange mode. 11,12 This is because the eluent cation was trapped by ion-dipole interaction with the oxygen atoms of multiple brush-type POE chains, and the eluent and analyte anions could compete for the trapped cation. Inorganic anions can therefore be separated on the POE-bonded phases in the ion-exchange mode, and nearly the same retention order as in common ion-exchange mode was observed.…”

Advanced analytical methods and sample preparation for ion chromatography techniques

“…10,37,[52][53][54][55][56] However, in practice the operator normally encounters real samples whose composition may vary considerably and which in many cases can only be analyzed by IC aer suitable sample preparation procedure. 10,37,[52][53][54][55][56] However, in practice the operator normally encounters real samples whose composition may vary considerably and which in many cases can only be analyzed by IC aer suitable sample preparation procedure.…”

Development of Micro-Flow-Controlled Techniques and Novel Stationary Phases in Capillary Liquid Chromatography

“…For example, sulfate and magnesium ions are kosmotropic ions while ammonium and perchlorate are chaotropic ions. Since PEG could provide hydrophobic interaction, it can be easily fixed on hydrophobic supports such as the common C18 stationary phase [57].…”