Unique Carbon LC U/HPLC Columns

Porous graphitic carbon from Merck is a novel stationary phase and gives the chromatographer an additional chemistry option in the separation of challenging compounds, beyond the realm of conventional silica-based reversed phase chromatography. While in many respects, PGC may behave like a reversed-phase column, it also offers the advantages of enhanced temperature, solvent, and pH stability. Moreover, because of the unique properties of graphite, highly polar compounds (that may need HILIC or ion-exchange conditions) can be retained on a PGC column. Although its retention mechanisms are yet to be elucidated, it is clear that PGC has unique retentive properties towards polar compounds - especially planar molecules or analytes with double bond conjugation that can interact with the electron cloud of graphite. PGC is a unique stationary phase amongst more conventional HPLC stationary phases and further advancements in PGC particle design may result in even better resolving power for a wider range of compounds.

The key advantages of using PGC columns over silica particle-packed columns include:

• Elevated Temperature Stability: Columns can be readily operated at temperatures up to 250 °C, thereby allowing faster and more efficient separations.
• pH Stability: Compatible with mobile phases in the pH range of 1 – 14 at any temperature without causing a decline in the column lifespan.
• Unique Retention Mechanism: The Polar Retention Effect on Graphite (PREG) mechanism allows for the retention of polar or charged compounds without hydrophilic interaction liquid chromatography (HILIC) conditions. The mechanism also allows the resolution of geometric isomers.
• Compatibility with Any Solvent: Any polar or non-polar solvent can be used for the resolution of an analyte of interest.
• Pressure Stability up to 700 bar.