Separation of unsaturated compounds on conventional reversed phase columns such as C8 and C18 is often problematic. Phenyl stationary phases are commonly used for these compounds because they form π-π interactions and show different selectivity from conventional alkyl phases. However, the π-π interactions on phenyl stationary phases are moderate, and the separation for some unsaturated compounds are still insufficient.

COSMOSIL πNAP is a Reversed Phase HPLC Column with naphtylethyl group bonded silica packing material. The naphthylethyl group is composed of two fused aromatic rings and forms strong π-π interactions with unsaturated compounds. This column offers improved selectivity for structural isomers that exhibit differences in saturation.