ZORBAX Eclipse Plus

Eclipse Plus columns provide the ultimate in performance for silica-based columns. Peak shape for the Eclipse Plus is excellent for the most challenging basic compounds, improving efficiency and resolution with these sample types. These results are achieved by improvements in the silica manufacturing and bonding technology, which is completely controlled by Agilent. To achieve fast method development and superior productivity, choose an Eclipse Plus column with high-resolution 1.8 µm particles. For standard methods, conventional 5 µm Eclipse Plus Columns and Rapid Resolution 3.5 µm Eclipse Plus columns are your best choices. With all particle sizes, easy method transfer is possible. Three different reversed-phase chemistries are available, Eclipse Plus C18, Eclipse Plus C8 and Eclipse Plus Phenyl-Hexyl. Eclipse PAH columns are recommended for the separation of polycyclic aromatic hydrocarbons. HILIC Plus columns are designed for hydrophilic interaction chromatography (HILIC) applications - typically used for the retention and resolution of small polar compounds. The reversed-phase chemistries are aligned with the Infinitylab Poroshell 120 EC-C18, EC-C8 and Phenyl-Hexyl chemistries, and HILIC Plus is very similar to InfinityLab Poroshell 120 HILIC. See more on InfinityLab Poroshell 120.



  • High level of performance – peak shape, efficiency, resolution, and lifetime – with all sample types: acids, bases and neutrals
  • Superior reproducibility with more rigorous QA/QC testing
  • Improved, patented silica manufacturing with start-to-finish product control
  • PAH column for high resolution separation of 16 PAHs in EPA 610 - specifically tested with PAHs for maximum reproducibility
  • HILIC column for good retention of small, polar analytes - recommended for EPA Method 1694
  • Available in 1.8, 3.5, and 5 μm particle sizes for all analytical, high resolution, and fast LC analyses
  • To compare technical information and specifications for different phases, see our phase specifications chart



Eclipse Plus columns are recommended for initial method development from pH 2-9 and provide high resolution and excellent peak shape of all types of compounds. Like all Eclipse columns Eclipse Plus columns achieve superior performance through extra dense bonding and a precise double-endcapping process. But Eclipse Plus columns also feature enhanced high-performance silica, new endcapping reagents, and a unique bonding process that is optimized for the improved silica.

Eclipse Plus columns are available in C18, C8, Phenyl-Hexyl, a C18 bonded phase for the separation of PAHs (polycyclic aromatic hydrocarbons), and unbonded silica HILIC Plus for hydrophilic interaction liquid chromatography . These phase choices provide the flexibility to rapidly separate all types of compounds. Eclipse Plus columns are available in particle sizes ranging from 1.8 µm to 5 µm RRHT to Prep.

Bonded Phase Pore Size Surface Area Temp. Limits pH Range* End capped Carbon Load USP Designation
ZORBAX Eclipse Plus C18 95Å 160 m2/g 60 °C 2.0 - 9.0 Double 9% L1
ZORBAX Eclipse Plus C8 95Å 160 m2/g 60 °C 2.0 - 9.0 Double 7% L7
ZORBAX Eclipse Plus Phenyl-Hexyl 95Å 160 m2/g 60 °C 2.0 - 8.0 Double 9% L11
ZORBAX Eclipse PAH 95Å 160 m2/g 60 °C 2.0 - 8.0 No 14% L1
ZORBAX HILIC Plus 95Å 160 m2/g 60 °C 0 - 8.0 N/A N/A L3

Specifications represent typical values only.

*Column lifetime will be reduced significantly at pH >7 and temperature > 40 °C. At pH 6-9, highest column stability for all silica based columns is obtained by operating at temperatures < 40 °C and using lower buffer concentrations in range of 0.01 0.02M, especially with phosphate and carbonate buffers.