The Ultra line represents Restek’s broadest selection of stationary phases on a single silica support.

• High-purity type-B silica
• High-density bonding
• Designed for selectivity

Since 2005, the Restek biphenyl has offered a greater degree of dispersion than conventional phenyls and a greater degree of polarizability than phenyl hexyls, creating higher selectivity and a greater range of usability. Because of these heightened interactions, this column shows substantial increases in retention—especially for dipolar, unsaturated, or conjugated solutes—and enhanced orthogonal selectivity when using methanol mobile phases. It is ideal for increasing sensitivity and selectivity in LC-MS analyses.