ACE C18-AR

ACE C18-AR

ACE® C18-AR phase utilises a specially developed ligand combining a C18 chain with integral phenyl functionality, thus combining the benefits of both C18 and phenyl characteristics into a single phase. This can be used for ‘standard’ C18 column separations, but is additionally recommended for separations that involve compounds containing aromatic functionality.


  • Ultra high purity, base deactivated silica with exceptional reproducibility
  • Ideal for a wide range of analytes differing in hydrophobicity
  • Wide range of particle sizes (2 to 10 µm) and complementary phases
  • Ultra low bleed to ensure LC-MS compatibility
  • ACE C18-AR
  • Differences
  • When to use
  • Column Inertness

Why do I need another new C18 phase?

The use of an ultra pure, ultra inert silica has many recognised benefits, including improved reproducibility, lifetime and chromatographic performance (particularly with basic molecules). However, since the ultra inert silica surface effectively no longer contributes to the separation, C18 columns manufactured with high purity silicas show near identical selectivity. It is therefore highly likely that a problem separation on one leading brand will not be significantly improved by changing to an alternate manufacturer’s equivalent product


For many years, experienced chromatographers have been seeking phases with the proven performance and reproducibility benefits shown by such leading C18 column brands, but which additionally provide the alternate selectivity required for their challenging applications.

How is ACE C18-AR different?

C18 bonded phases currently dominate the HPLC market, with recent surveys indicating that they are still responsible for 50-60% of all HPLC columns sold. However, in recent years the use of Phenyl bonded phases has grown significantly, due to the alternate selectivity they provide. It is estimated that Phenyl phases now account for 10-15% of HPLC column sales, making them the largest sub-category after C18 phases. The ACE C18-AR phase utilises a specially developed ligand combining a C18 chain with integral phenyl functionality, thus combining the benefits of both C18 and Phenyl characteristics into a single phase. Based upon the same ultra inert, ultra pure, ultra reproducible silica platform as ACE C18, the unique ACE C18-AR phase provides an alternate selectivity to C18 columns.


When should I use ACE C18-AR?

Due to their similar hydrophobic characteristics, ACE C18-AR columns may be used for applications in which “standard” C18 columns would normally be considered. However, due to its integral phenyl functionality, ACE C18-AR is additionally recommended for separations that involve compounds containing aromatic functionality.


ACE C18-AR can be used to improve separations that are proving problematic on C18 columns. The unique ACE C18-AR phase provides an alternate selectivity to C18 columns, but remains a valid selection for methods in which C18 bonded columns are specified. In many instances, the same evaluation conditions that prove unsuitable for the C18 column prove suitable for the C18-AR column, avoiding the need for lengthy method redevelopment.

Ultra Inert Silica for Excellent Chromatography

Many columns designed for use under high aqueous conditions are compromised by the low purity silica employed and exhibit poor peak shape with polar basic molecules. This results in poor chromatography and ultimately leads to poor column reproducibility. ACE C18-AR columns are manufactured from the same ultra inert, high purity silica as all ACE phases – ensuring excellent chromatography and excellent reproducibility are obtained.