Technical Note 20788
Comparison of the Reversed-Phase
Selectivity of Solid Core HPLC Columns
M. Dolci, L. Pereira, Thermo Fisher Scientific, Runcorn, Cheshire, UK
Introduction
Accucore HPLC columns are based on Core Enhanced
Technology™, which features solid core materials with a
very tight particle size distribution and advanced bonding
technology to functionalize the surface. The particles in
the Accucore stationary phases can be described as a solid
silica core surrounded by a porous outer layer. The very
tight particle size distribution of these materials results in
columns with high permeability. Therefore, for the same
nominal pressure, Accucore particles provide better
separations than fully porous materials.
In this technical note the retention properties of Accucore
C18 and Accucore RP-MS (an optimized alkyl chain
length bonded phase) materials are compared to other
solid core reversed-phase C18 materials. To fully
characterize the surface chemistry of the reversed-phase
materials, a series of diagnostic chromatographic tests
were used (based on those developed by Tanaka [1]).
These tests characterize analyte/stationary phase
interactions and combine probes to measure
hydrophobicity, shape selectivity, hydrogen bonding, and
secondary interactions with bases, acids, and chelators.
The results from this characterization study will help
users to select the best phase for their separations. These
tests are described in Tables 1 to 3.
Key Words
Accucore, solid core, column characterization, selectivity, primary
interactions, secondary interactions, Core Enhanced Technology, radar plots
Abstract
The selectivities of Thermo Scientific™ Accucore™ C18 and RP-MS phases
are compared to six other solid core reversed-phase stationary phases.
The retention properties of the stationary phases were categorized by
analyzing primary modes of interaction (hydrophobicity, steric selectivity,
and hydrogen bonding) and secondary modes of interaction (ion exchange
and chelation).
The phase characterization data obtained were
summarized in radar plots, which allow visual comparison
of the overall selectivity of the different stationary phase
chemistries. Radar plots, also known as spider or star
charts (because of their appearance), plot the values of
each category along a separate axis that starts in the
center of the chart and ends on the outer ring.
1...,9,10,11,12,13,14,15,16,17,18 20,21,22,23,24,25,26,27,28,29,...58