Characterization and kinetic performance of 2.1 × 100 mm production columns packed with new 1.6 μm superficially porous particles.

The overall kinetic performance of three production columns (2.1 mm × 100 mm format) packed with 1.6 μm superficially porous CORTECS-C18 + particles was assessed on a low-dispersive I-class ACQUITY instrument. The values of their minimum intrinsic reduced plate heights (h(min) = 1.42, 1.57, and 1.75) were measured at room temperature (295 K) for a small molecule (naphthalene) with an acetonitrile/water eluent mixture (75:25, v/v). These narrow-bore columns provide an average intrinsic efficiency of 395,000 plates per meter. The gradient separation of 14 small molecules shows that these columns have a peak capacity about 25% larger than similar ones packed with fully porous BEH-C18 particles (1.7 μm) or shorter (50 mm) columns packed with smaller core-shell particles (1.3 μm) operated under very high pressure (>1000 bar) for steep gradient elution (analysis time 80 s). In contrast, because their permeabilities are lower than those of columns packed with larger core-shell particles, their peak capacities are 25% smaller than those of narrow-bore columns packed with standard 2.7 μm core-shell particles.