Ascentis C18 HPLC Columns

The First Choice for Classic C18 Retention and Selectivity

Optimization of silica and bonded phases make Ascentis C18 a true workhorse for the vast majority of HPLC separations. High surface area and phase stability give it perfect character for demanding LC-MS and preparative separations.


  • Classic C18 selectivity
  • High non-polar retentivity
  • Symmetric peak shape
  • Highly reproducible and stable
  • Ideal for LC-MS

Key Applications

General reversed phase, hydrophobic and polar compounds

Ordering Information for Ascentis C18 HPLC columns

USP Code: L1
Bonded Phase: Octadecyl
Endcapped: Yes
Particle composition: Type B silica gel
Particle Purity: <5 ppm metals
Particle Shape: Spherical
Particle Size: 3, 5 and 10 µm
Pore Size: 100 Å
Surface Area: 450 m2/g
Carbon Load: 25 %
pH Range (recommended): 2 to 8
Extended pH range*: 1.5 to 10


The classic reversed-phase column, Ascentis C18 is suitable for any method that specifies a C18-type column. Its high surface area gives Ascentis C18 strong hydrophobic retention and high loading capacity for preparative applications.

LC-MS Implications

Ascentis C18 is low-bleed for clean ESI and APCI traces. The high retentivity means that the mobile phase can contain high levels of organic modifier that are more readily desolvated.


Modern C18 columns have very similar selectivity, even for basic compounds, because silica quality and bonding techniques have improved to the point that silanol effects are minimal. Unless quality with your current column is the issue, the main reasons for evaluating different brands of C18 columns are for improved peak shape and for slight changes in selectivity.

* Under certain conditions, the Ascentis family can be operated in the extended pH range. For more details, see “Acid/Base Stability of Silica Based on C8, C18, and Amide HPLC Columns” (T406018 - 530Kb pdf)