Ultra Aqueous C18 Columns by Restek Corp.

The Ultra line represents Restek’s broadest selection of stationary phases on a single silica support. Made of high-purity, type-B silica that minimizes activity and creates high-density bonding, these columns are designed for selective and reliable HPLC applications.

The Ultra Aqueous C18 HPLC column provides reproducible retention times and can be used with highly aqueous mobile phases, which may eliminate the need for sample derivitization or ion pairing reagents. This column features a true C18 alkyl bonded phase, meeting the requirements of a US Pharmacopoeia (USP) L1 stationary phase.

The Ultra Aqueous C18 column uses a novel bonding chemistry that results in polar groups at the silica surface. These surface polar groups keep the alkyl stationary phase extended, and thus wetted by the mobile phase—even when using up to 100% aqueous mobile phases.

Additionally, although the Ultra Aqueous C18 column behaves similarly to a traditional base-deactivated C18 column when analyzing neutral hydrophobic compounds, it has enhanced retention and unique selectivity for polar and basic compounds.


Ultra Aqueous C18 Columns Features:

• Analyzes polar compounds by reversed phase.
• Retains compounds such as amino acids and water soluble vitamins using simple mobile phases and without derivitization.
• Analyzes polar, hydrophillic materials without retention time loss. Stable retention in 100% aqueous mobile phases.
• Can analyze compounds that are sparingly soluble in organic solvents.
• True C18 alkyl bonded phase.
• High-density C18 ligand coverage.
• Similar selectivity as traditional C18 phases for neutral hydrophobic compounds.
• Unique secondary polar characteristics.
• End-capping diminishes peak tailing observed from exposed silanol sites on the silica surface.

Column Characteristics:

• Phase: C18
• particle Size: 3, 5 μm
• Pore Size: 100 Å
• Length: 30, 50, 100, 150, 200, 250 mm
• ID: 0.3, 1.0, 2.1, 3.0, 3.2, 4.6 mm