Data Sheet (pdf)

ZIC®-pHilic

for the seperation of polar and hydrophilic compounds
and high pH range

ZIC®-pHILIC is a hydrophilic stationary phase with permanently charged zwitterionic groups covalently attached to a polymeric support particle. The HILIC separation mode utilises an eluent containing a high content of water miscible organic solvent (e.g., acetonitrile) to promote hydrophilic interactions between the analyte and a hydrophilic stationary phase. It is thus comparable to traditional normal phase chromatography. However, with respect to analyte solubility in the mobile phase and matrix compatibility, HILIC is superior, as the mobile phase compositions used are related to reversed phase separations. Analytes with poor retention in reversed phase chromatography (RPLC) can typically be well retained and separated using the ZIC®-pHILIC column. For example, compounds such as peptides, carbohydrates, plant extracts, protein digests and other polar compounds might be highly suitable for separation. Both isocratic- and gradient separations can be carried out depending on the complexness of the particular separation.

Schematic illustation of the ZIC®-pHILIC stationary phase.

As the stationary phase is polymeric resin, the column can be operated in a broad pH range. Generally, the ionized forms of an analyte are more polar than its uncharged analogue, which usually translates into higher retention in HILIC mode chromatography. The eluent pH is therefore a powerful tool for tuning the selectivity, retention and resolution. Since many silica-based stationary phases suffer from low stability in even moderately alkaline solutions, they are typically limited to applications below pH 7.5-8.

The ZIC®-pHILIC columns also provide a high degree of freedom when optimising the sensitivity in LC/MS applications, since volatile eluents in with pH from the acidic to alkaline range might be employed.

Figure 1 shows how the retention and selectivity for a separation of gentisic acid, protocatechuic acid and isophthalic acid can be optimised simply by changing the eluent pH from 6.8 (ammonium acetate buffer) to 9.6 (ammonium carbonate buffer)

Separation of gentisic acid, protocatechuic acid and isophthalic acid on a ZIC®-pHILIC column 100 x 4.6 mm. Eluent: 75:25 acetonitrile/aqueous buffer pumped at 0.5 mL/min. Buffer salt: ammonium acetate
(17 mM, pH 6.8) or ammonium
carbonate (17 mM, pH 9.6).

Column Type

Paricle Size

Pore Size

Length

ID

Pack of

Prduct No.
Analytical Column 5 µm 200 Å 50 mm 2.1 mm 1 pcs. 8SQ2812-052
PEEK
5 µm 200 Å 100 mm 2.1 mm 1 pcs. 8SC2812-102
5 µm 200 Å 150 mm 2.1 mm 1 pcs. 8SQ2812-152
5 µm 200 Å 50 mm 4.6 mm 1 pcs. 8SQ2812-055
5 µm 200 Å 100 mm 4.6 mm 1 pcs. 8SQ2812-105
5 µm 200 Å 150 mm 4.6 mm 1 pcs. 8SQ2812-155
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