Catalog Number - 40008-15P-2

The 40008‑15P‑2 Cogent Bidentate C8™ HPLC Column is a long‑format, narrow‑bore analytical column designed for applications where maximum resolution and alternative reversed‑phase selectivity are required. Built on Cogent TYPE‑C™ silica hydride technology, this column delivers excellent selectivity, faster equilibration, and extremely robust column lifetime compared with conventional silica‑based C8 phases.

The stationary phase features an aliphatic C8 hydrocarbon chain bonded via two direct silicon–carbon bonds (bidentate attachment) to a silica hydride surface. This non‑traditional chemistry produces a phase that is more hydrophobic than standard C8 columns, yet less hydrophobic than Bidentate C18™, making it ideal when C18 retention is excessive but stronger retention than conventional C8 is still needed. Unlike traditional C8 columns, this phase can also retain select hydrophilic compounds, expanding method‑development flexibility.

The 2.1 mm internal diameter supports low‑flow operation, reduced solvent consumption, and enhanced detector sensitivity, while the extended 150 mm length provides the highest resolving power in the standard‑particle Bidentate C8™ lineup. As a result, this column is often chosen for LC‑MS workflows when closely eluting analytes require additional separation beyond what 50 mm or 100 mm formats can deliver.

The column is also stable at very low pH (below pH 2) with no degradation, enabling aggressive analytical methods that are not possible with conventional silica‑based C8 phases.

Why Choose the 2.1 × 150 mm Bidentate C8™ Format

This column size is commonly selected when:

• C18 columns provide excessive retention or poor peak spacing

• Standard C8 columns lack sufficient resolution

• Maximum separation of closely eluting compounds is required

• LC‑MS sensitivity and solvent‑use reduction are priorities

The 150 mm length increases plate count and resolving power, while TYPE‑C™ silica hydride chemistry maintains fast equilibration and long column life despite the longer column format.

Key Features

Cogent TYPE‑C™ Silica Hydride Technology

• Non‑traditional reversed‑phase surface chemistry

• Reduced silanol activity and secondary interactions

• Faster equilibration than conventional silica‑based C8 columns

• Extremely robust and reproducible performance

Bidentate C8™ Bonding

• Two‑point attachment via direct Si–C bonds

• Balanced hydrophobic retention

• Alternative selectivity when C18 is overly retentive

Maximum‑Resolution Narrow‑Bore Geometry

• 2.1 mm ID × 150 mm length

• Highest resolution among standard‑particle C8 options

• Reduced solvent consumption at low flow rates

LC‑MS‑Optimized Format

• Ideal for ESI‑MS and LC‑MS/MS workflows

• Enhanced sensitivity at reduced flow rates

• Requires precise low‑flow pumping and reduced‑volume flow cells

Broad Method Compatibility

• Stable at very low pH (below 2)

• Compatible with aqueous‑rich mobile phases

• Suitable for aggressive and unconventional analytical methods

System Requirements

For optimal performance with this long, narrow‑bore column:

• Use a pump capable of accurate, stable low‑flow delivery

• Employ detector flow cells designed for low internal volumes

Typical Applications

• LC‑MS and LC‑MS/MS

• Hydrophobic and moderately polar compounds

• Situations where C18 retention is excessive

• High‑resolution reversed‑phase methods

• Advanced method development and optimization