SeQuant® ZIC®-pHILIC Polymeric

Use SeQuant® ZIC®-pHILIC HPLC Columns for More Difficult Separations of Polar Hydrophilic Compounds.

SeQuant® ZIC®-pHILIC HPLC columns are the preferred choice when extreme eluent conditions are needed to overcome challenging separations of polar hydrophilic compounds. Offering excellent pH stability from pH 2 to 10, these polymer-based columns carry densely bonded, truly zwitterionic functional groups with a charge balance of 1:1. This results in straightforward and reproducible separations with wide-spectrum pH tuning for optimal separation selectivity and detection sensitivity. Furthermore, SeQuant® ZIC®-pHILIC columns minimize background noise in evaporative detection techniques with high sensitivity to ions, such as charged aerosol detectors (CAD). SeQuant® ZIC®-pHILIC columns are available with 5 µm polymer particles in various formats of analytical dimensions. Alternative choices for the separation of polar hydrophilic compounds include silica-based SeQuant® ZIC®-HILIC columns with identical functional groups, and SeQuant® ZIC®-cHILIC columns with complementary selectivity.

Independent Column Comparison

Researchers of an American pharmaceutical company compared several HILIC columns of different brands for the analysis of counter ions using a charged aerosol detector. According to their results, ZIC®-pHILIC offered favorable selectivity and peak shapes with minimum background noise – a combination not achieved with the other columns tested. “When operating on ZIC®-pHILIC columns, the baseline noise was negligible (<3 pA) and not affected by increasing the aqueous percentage of the eluent.” (Huang et al., J. Pharm. Biomed. Anal. 50 (2009) 809-814)

Read the Article

What is HILIC?

HILIC or hydrophilic interaction liquid chromatography is a high-performance liquid chromatographic (HPLC) technique for separation of polar and hydrophilic compounds. Simply put, HILIC is a normal-phase type of separation but uses reversed-phase type eluents. Thus, it unites the benefits of aqueous mobile phases with separation based on normal phase principles in which more polar compounds respond with higher retention. This results in more efficient separation. Furthermore, HILIC is easy to combine with a wide range of detection methods, and boasts improved sensitivity with some of these techniques, such as electrospray ionization mass spectrometry (ESI-MS).

Application Examples

SeQuant® ZIC®-pHILIC columns have been used for a wide range of applications, and are often preferred for difficult separations in which high mobile phase pH is required for enhanced selectivity, stability or sensitivity of analytes.

Separation of Gentisic Acid, Protocatechuic Acid, and Isophtalic Acid

Column	ZIC®-pHILIC (5 µm, polymer) PEEK 100x4.6 mm
Mobile phase	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

Gradient	Time	%A	%B
	0	20%	80%
	15	60%	40%
	20	60%	40%
	35	20%	80%
Column	ZIC®-pHILIC (5µm, polymer) PEEK 150x2.1 mm
Mobile phase	A: Acetonitrile B: 10 mM (NH4)2CO3 + 0.2% NH4OH
Sample	Pantothenate (2, structure), Acetyl-CoA (3), AMP (4), CoA (5), ADP (6), and ATP (7).
Courtesy of	T. Pluskal, K. Nagao, M. Yanagida, GO Cell Unit, Initial Research Project Okinawa Institute of Science and Technology, Okinawa 904-2234, Japan.

SeQuant®  Column	Functional group	Features	Base particle	Particle size	Pore size	Column types
SeQuant®  ZIC®-pHILIC	Sulfobetaine	High pH-stability and low noise with ion detectors	polymer	5 µm		analytical, guards

Technical Support for SeQuant® HILIC Columns

Merck offers several technical support services to help you achieve optimal separations and reliable analytical results with SeQuant® HILIC products.

SeQuant® FAQ list

Download instructions