Ascentis C8 HPLC Columns

One of The Most Hydrophobic C8 Phases Available

Leveraging the improvements to silica and bonded phase properties that made Ascentis C18 so useful, its shorter alkyl chain cousin, Ascentis C8, is also suitable for routine HPLC and LC-MS.


  • Selectivity similar to C18 for non-polar compounds
  • Different selectivity for polar compounds
  • Less hydrophobic than C18, more hydrophobic than other C8 phase
  • Symmetric peak shape
  • Highly reproducible and stable
  • Ideal for LC-MS

Key Applications

Small, water soluble molecules and peptides, less hydrophobic retention than C18 but comparable selectivity, LC-MS

Ordering Information for Ascentis C8 HPLC columns

USP Code: L7
Bonded Phase Description: Octyl
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: 15 %
pH Range (recommended): 2 to 8
Extended pH range*: 1.5 to 10


Ascentis C8 is suitable for any method that specifies a C8-type column. Although C8 columns often show similar selectivity to C18 columns, shorter alkyl chains sometimes show different selectivity toward polar compounds because they can solvate differently with the mobile phase and interact differently due to the size and shape of certain molecules. Also, C8 reagents are smaller than C18 reagents and have improved primary phase coverage, thereby requiring less endcapping. Ascentis C8 has excellent peak shape and very high phase stability.

Among commercially available C8 columns, Ascentis C8 has the highest degree of hydrophobic retention. This permits the use of higher percentages of organic modifier, a benefit to LC-MS users.


* 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)