CUSTOM ITEM: HPLC Column, Bidentate C18, 4um, 3.0mm ID x 250mm Length, 100A. Cogent TYPE-C Brand. 1 EA.
Additional Info:
The 40018‑25P‑3 Cogent Bidentate C18™ HPLC Column is a custom‑manufactured, long‑format mid‑bore column designed to deliver the highest resolving power in the Bidentate C18™ family while using significantly less mobile phase than equivalent 4.6 mm ID columns. Built on Cogent TYPE‑C™ silica hydride technology, this column provides unique selectivity, rapid equilibration, and exceptional chemical robustness for demanding analytical methods.
The stationary phase utilizes an aliphatic C18 chain bonded via two direct silicon–carbon bonds (bidentate attachment) to a silica hydride surface. This chemistry produces a surface that is highly hydrophobic yet versatile, enabling retention of compounds that often show weak or inconsistent retention on conventional silica‑based C18 columns. Unlike traditional C18 phases, this column supports 100 % aqueous mobile phases without phase collapse and tolerates very low pH conditions (below pH 2) with no damage.
The 3.0 mm internal diameter allows operation at lower flow rates, reducing solvent consumption and waste, while delivering run times comparable to 4.6 mm ID columns. The extended 250 mm length maximizes plate count and selectivity, making this format the preferred choice for closely related compounds, isomers, or complex mixtures that require the greatest separation power—without requiring specialized low‑flow instrumentation.
Why Choose the 3.0 × 250 mm Bidentate C18™ Format
This configuration is commonly specified when:
Maximum analytical resolution is required
Shorter columns (50–150 mm) do not provide adequate separation
Solvent‑use reduction is a priority without changing instrumentation
Methods operate at low pH or with aqueous‑dominant mobile phases
The combination of long column length and TYPE‑C™ silica hydride chemistry delivers exceptional separation performance while maintaining fast equilibration and long column life.
Key Features
Cogent TYPE‑C™ Silica Hydride Technology
Reduced silanol activity and secondary interactions
Faster equilibration than conventional C18 columns
Extremely robust column lifetimes
Bidentate C18™ Bonding
Two‑point attachment via direct Si–C bonds
Unique selectivity not achievable with standard C18 phases
Retains strongly hydrophobic and select hydrophilic analytes
Maximum‑Resolution, Solvent‑Efficient Geometry
3.0 mm ID × 250 mm length
Highest plate count in a mid‑bore format
Lower solvent consumption than 4.6 mm ID columns
Compatible with standard analytical HPLC systems
Broad Method Operating Window
Stable with 100 % aqueous mobile phases
Resistant to degradation at very low pH (below 2)
Suitable for aggressive and unconventional reversed‑phase methods
Typical Applications
High‑resolution analytical HPLC
Closely related compounds and isomer separations
Complex mixtures requiring extended retention
Low‑pH reversed‑phase methods
Aqueous‑dominant mobile‑phase separations
Solvent‑reduction initiatives
Custom Order Information
This product is classified as a Custom Item. Custom items are manufactured to order, non‑returnable, and cannot be canceled once production has begun.
Please contact Customer Service for lead time confirmation, documentation, or customization inquiries.