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OmniPac PAX-100 Anion-Exchange Column

Anion-Exchange Column for the Analysis of Hydrophobic and Halogenated Anions

The OmniPac® PAX-100 column is a microporous, solvent-compatible, high-capacity, anion-exchange column designed for the separation of hydrophobic anions, and specifically very hydrophobic and halogenated anions. All neutral matrix components are eluted in the void volume.

  • Acid, base, and solvent-compatible, pH 0–14
  • Well suited for the separation of high-molecular-weight organic acids
  • Good for the separation of very hydrophobic anions
  • Good for the separation of halogenated anions

The OmniPac PAX-100 column was one of the first solvent-compatible, anion-exchange columns for the separation of inorganic and organic anions providing acid and base compatibility over the entire pH range. Because the OmniPac PAX-100 is solvent compatible, solvents can be used to modify the ion-exchange selectivity. Additionally, solvents can be used to solubilize otherwise insoluble samples, or to remove organic impurities from the column to prolong column life. The OmniPac PAX-100 is 100% solvent compatible and should always be run with at least 1% organic solvent in the mobile phase.

The OmniPac PAX-100 column is particularly well suited for the analysis of larger organic acids, including alkylbenzene sulfonates, aromatic acids, barbiturates, polyphosphates, inositol phosphates, thiocyanate, thiosulfate, and iodate. For separations of inorganic and low-molecular-weight organic acids, the IonPac® AS11 and IonPac AS11-HC are suitable alternatives that may provide different selectivities. The IonPac AS11 and AS11-HC may also be considered as viable alternate columns for larger organic acid applications.