Solid-Core Primesep S
HILIC mode is required for the retention of zwitterionic compounds because of the difficulty in to have stationary phase be ionized enough to retain weak basic compounds such as amino acids.
Basic drugs can be retained and separated by the HILIC/cation-exchange mechanism on Primesep S Columns. Dopamine and epinephrine can be separated within 1 minute with high efficiency and a perfect peak shape (Fig. 3). In the case of hydrophobic basic molecules, ion-exchange mode can be employed without HILIC being present. At low concentrations of MeCN, only cation-exchange mode is present and the retention time is dependent on pH and buffer concentration. A mixture of isomers of toluidine was separated within 3 minutes (Fig. 4).
In general, Primesep S Columns offer alternative selectivity not only to reverse-phase Columns, but also to traditional HILIC Columns (cyano, diol, bare silica, zwitter-ionic). Retention time and elution depends on the concentration of MeCN , buffer pH, buffer concentration, and the nature of the buffer.
The retention time of compounds can be adjusted independently. Various mobile phases can be employed to suit the particular detection technique that is used (Fig. 5).
Solid-Core Primesep S columns are available in all standard dimensions
Column IDs: 22 mm, 10 mm, 4.6 mm, 3.2 mm, 2.1 mm, 1 mm, 0.5 mm, 0.25 mm
Column Lengths: 250 mm, 150 mm, 100 mm, 50 mm, 25 mm, 10 mm
Particles: 2.7 µm
Pores: 100 A