C18 Reversed Phase HPLC Columns comparison Guide Independently Tested at The University of Aberdeen, UK

An Independent Comparison of Leading C18 Column Brands gave the following conclusion:

Significant differences in efficiency, peak shape and selectivity are seen with C18 bonded columns when evaluating acidic and basic compounds. These variations are caused by undesirable secondary silanol interactions. The selection of a high efficiency base deactivated phase with very low silanol activity will prove highly beneficial for the majority of  analyses.
Professional chromatographers chose their columns based on hard technical facts. Below you find comparison data on commonly used C18 phases.

It includes

• Stationary phase specifications
• Phases compared according to relative hydrophobicity
• Comparison of column efficiency for a neutral compound
• Phases compared according to metal activity
• Phases grouped according to silanol activity
• Comparison of column efficiency for basic compounds
• Categorisation of phases according to silanol activity and inertness