Exploiting HPLC and UHPLC Selectivity With Rational Stationary Phase Design

Alan P McKeown

In this seminar, we explore the power of selectivity using the resolution equation in HPLC and UHPLC. Using a variety of chromatographic data, we discuss how incorporating an aromatic building block in phase design has led to the unique bonded phases ACE® C18-AR and ACE® C18-PFP. These unique phases have been engineered based upon the popular ACE® C18 phase due to its generally well known and advantageous characteristics that include ultra-inert base silica, excellent phase stability / robustness, hydrophobicity, low ligand bleed and superb batch to batch and column to column reproducibility.

In addition to the hydrophobic interaction mechanism contributed by the C18 ligand, the ACE® C18-AR and ACE® C18-PFP phases have been specifically designed to confer multiple modes of interaction with analytes to effect separations without compromising reproducibility. The potent combination of these mechanisms in each phase appears to provide new options for the chromatographer involved in method development or screening. This is further underlined by phase characterisation data and also Selectivity plots which indicate a high degree of orthogonality.

Various examples and chromatography challenges for both HPLC (with ACE® columns) and UHPLC (with ACE® Excel ™ columns) where selectivity has provided the separation solution will be illustrated. Experiments and observations when moving methods between HPLC and UHPLC modes will also be discussed.