Comparison study of porous, fused-core, and monolithic silica-based C18 HPLC columns for Celestoderm-V Ointment® analysis

In this paper, three C18 columns with different substrates (i.e., porous ACE-3 C18, 3 μm, fused-core Halo C18, 2.7 μm, and monolithic Chromolith C18) were compared for the analysis of a pharmaceutical product, Celestoderm-V Ointment®, that contains one active pharmaceutical ingredient, betamethasone-17-valerate and one critical pair of low level impurities, betamethasone-E-enolaldehyde and betamethasone-Z-enolaldehyde. Key column performance for the analysis of pharmaceutical products including selectivity, efficiency, separation impedance, resolution factor, sample loading capacity, linearity and lifetime from the three columns were determined. The potential applications of these three C18 columns for different methods for Celestoderm-V Ointment® analysis are also recommended.