Orthogonal HPLC Method Development – AppNote

Choose Reversed or Normal Phase Selectivity on the Same C18 Column In the Chromatogram (A) below, a Reversed Phase Method Strategy is used: Loratadine in 100% Tetrahydrofuran (THF) elutes with the Solvent Front. With 70:30 DI Water / Tetrahydrofuran (THF), the Selectivity for this Compound is Reversed Phase, which is based on polarity of the […]

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Phenolic Compounds Analyzed with Normal Phase HPLC – AppNote

Cogent Silica-C™ Compared to Standard Silica in Normal Phase HPLC The Cogent Silica-C Column was compared with a different brand and type of Silica Column for Separation of three proprietary, large, substituted Phenol Compounds using Normal Phase HPLC . The Cogent Silica-C Column provided satisfactory Selectivity under isocratic elution conditions. The Column displayed typical Normal […]

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Prep HPLC in Normal Phase on C18 Column – AppNote

“Prep up” in NP with a Step Gradient and “Check Purity” in RP on the Same Column Two compounds with similar Polarity but different Function Groups, that can be typically Resolved in Isocratic Reversed Phase conditions, are more Separated using this Method with Normal Phase Conditions (non Polar Solvents); without the characteristic hassles associated with […]

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