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ACE SuperC18

ACE SuperC18

    ACE SuperC18:
  • Exploit selectivity at low, intermediate and high pH
  • Use with LC/MS compatible buffers between pH 1.5 – 11.5
  • High efficiency 2μm, 3μm, 5μm and 10μm particles for UHPLC and HPLC
  • Ultra-inert for maximum performance and reproducibility
  • EBT (TM)
  • Inertness - pH5.8
  • Exploiting Selectivity
  • Inertness - pH10.7

Encapsulated Bonding Technology (EBT™) for improved chromatography and stability

The unique Encapsulated Bonding Technology (EBT™) developed for ACE SuperC18 columns dramatically increases ligand coverage of the silica surface and effectively eliminates the effect of unbonded silanol groups from separations.This higher ligand coverage results in improved inertness, chromatographic performance and stability.


Under aggressive acidic conditions (see Figure 1) ACE SuperC18 is highly resistant to ligand cleavage, due to a combination of the Encapsulated Bonding Technology (EBT™) and ultra-inert ACE silica. Many C18 bonded columns will exhibit ligand cleavage under acidic conditions, resulting in retention shifts and/or increased peak tailing.


Under basic conditions with LC/MS compatible mobile phases (see Figure 2), the Encapsulated Bonding Technology (EBT™) shields the ACE SuperC18 surface from dissolution whilst maintaining excellent chromatographic performance. Traditional C18 bonded silica columns are prone to silica dissolution under such aggressive conditions, which can result in premature column deterioration.


The 'Porous ACE SuperC18 buffer guide' is available on the download tab.

Comparison of Column Inertness at Intermediate pH

Significant differences in efficiency, peak shape and selectivity are seen when analysing pyridine – a basic molecule. - see figures below


Increased tailing and retention, combined with reduced efficiency, are indicative of undesirable secondary interactions between pyridine and silanol groups on the stationary phase surface.


These interactions can also result in poor column reproducibility.


ACE C18 columns have gained a well deserved reputation for providing excellent efficiency, peak shape and reproducibility . ACE SuperC18 columns further build upon this proven reputation to provide the analyst with even better chromatographic performance across an extended range of pH conditions under LC/MS compatible conditions.


Exploit selectivity by adjusting pH

Ideal column choice for method development
  • Exploit selectivity changes at low, intermediate and high pH
  • Excellent column lifetime for reduced analysis costs

Specially designed for high and low pH mobile phases
  • Designed for use with LC/MS compatible buffers
  • Recommended pH range 1.5 – 11.5

Ultra-Low Bleed for Improved LC/MS Compatibility
  • Designed for use with LC/MS compatible buffers
  • Rapid column equilibration without memory effects

Preparative dimensions available
  • Reproducible scale up from analytical separations
  • Exploit increased loading capability at elevated pH

Comparison of Column Inertness at High pH

When analysing a basic molecule (pyridine) at high pH, differences in efficiency, peak tailing and retention are seen. This suggests undesirable secondary interactions between the basic molecule and silanol groups on the stationary phase surface remain.


Further to the intermediate pH comparison (see Inertness-pH5.8 tab), the ACE SuperC18 again provides excellent peak shape and efficiency when analysing a basic molecule (pyridine) at high pH, indicating undesirable secondary interactions have been virtually eliminated. These undesirable interactions can also result in poor column reproducibility.


Changing pH is a powerful tool to enable the selectivity to be optimised and sample impurities to be identified. ACE SuperC18 columns are designed to provide excellent peak shape and lifetime under acidic, intermediate and high pH with LC/MS compatible buffers, and may additionally be used with mobile phases containing MeOH or MeCN without suffering efficiency loss and/or extended equilibration times.