The OmniPac^® PAX-500 column is a macroporous, low-capacity, solvent-compatible column designed to separate anionic and neutral species in a single run. This column combines both anion-exchange and polymeric reversed-phase retention mechanisms in a single column.

• Good for the simultaneous separation of neutral and anionic species
• Unique selectivity for polar and ionic organic analytes
• Effective for biological samples such as purines, pyrimidines, and vitamins
• Good for drugs and pharmaceuticals

The multimode separation mechanism of the OmniPac PAX-500 is achieved by coating a macroporous, hydrophobic core for reversed-phase retention, with an anion-exchange latex bead layer for anion-exchange retention. The macroporous structure provides an accessible hydrophobic core where reversed-phase retention occurs. The anion-exchange selectivity is provided by an anion-exchange MicroBead^TM latex that coats the hydrophobic core. Since the anion-exchange layer is identical to that of the OmniPac PAX-100, the two columns exhibit similar ion-exchange selectivity. As a result, the OmniPac PAX-100 can be used to develop the ion-exchange separation and the method can then be transferred to the OmniPac PAX-500 for refinement to include the reversed-phase separation. The OmniPac PAX-500 column is 100% solvent compatible and should always be run with at least 1% organic solvent in the mobile phase to maintain column life.

The OmniPac PAX-500 may be used for the separation of compounds such as alcohols, alkanolamines, antihistamines, anti-inflammatory agents, aromatic acids, inorganic acids, peptides, purines and pyrimidines, sulfonamides, sulfonated anionic surfactants, and water-soluble vitamins.