GP-C18 uses full coverage bonded silica packing, which provides exceptionally high stability. The unique mono-functional bonding chemistry of GP-C18 avoids the formation of multiple C18 layers. Such uniform stationary phase allows the separation to achieve high selectivity and high efficiency.

Monomeric and fully endcapped GP-C4 packing is bonded with butyl groups that lead to moderate hydrophobicity. GP-C4 columns have unique selectivity and peak symmetry with moderate retention for separations of acidic, neutral and basic organic compounds, such as pharmaceuticals, peptides, and organic acids.

GP-C8 phase is synthesized with monomeric and fully endcapped chemistry. The uniform octyl stationary phase allows high efficiency with lower hydrophobicity compared to ODS phase. GP-C8 phase is suitable for separating compounds with a wide range of hydrophobicity. It is highly recommended for separating the compounds which are too strongly retained on C18 phases.

GP-Phenyl packing materials are bonded with propyl phenyl groups that enable special interaction with ring structured compounds. The monomeric bonding chemistry gives high efficiency and high resolution separations. GP-Phenyl phase is suitable for separations of acidic, neutral and basic organic compounds, as well as pharmaceuticals.