Three isomers of aminopyridine separate well by reversed-phase cation-exchange mixed-mode chromatography on an Obelisc R HPLC column. The presence of additional mechanism of interaction provides great selectivity for separation of closely related compounds. Elution of compounds can be monitored by UV, Evaporative Light-Scattering Detector (ELSD), Corona (CAD) or LC/MS. This method was validated at a pharmaceutical company. This HPLC method can be adopted as general approach for analysis of aminopyridine and other isomeric compounds.
SIELC has developed the Obelisc™ columns, which are mixed-mode and utilize Liquid Separation Cell technology (LiSC™). These cost-effective columns are the first of their kind to be commercially available and can replace multiple HPLC columns, including reversed-phase (RP), AQ-type reversed-phase, polar-embedded group RP columns, normal-phase, cation-exchange, anion-exchange, ion-exclusion, and HILIC (Hydrophilic Interaction Liquid Chromatography) columns. By controlling just three orthogonal method parameters - buffer concentration, buffer pH, and organic modifier concentration - users can adjust the column properties with pinpoint precision to separate complex mixtures.Select options