Professor Alpert introduced a new concept in 1990: hydrophilicity chromatography (HILIC). This chromatographic method is used to separate strong polar and hydrophilic compounds, such as nucleosides and nucleotides, amino acids, sugars, etc. Besides, it uses polar stationary phase, polar mobile phase, and solutions with lower polarity than stationary phase, such as acetonitrile/water, etc. Different from reverse phase chromatography, the greater the polarity of mobile phase, the stronger the elution ability in HILIC chromatography. Nevertheless, it is recommended that aqueous phase proportion should not exceed 40% or not less than 3%.
HILIC principle is still under study today, and the most widely accepted statement says it is because of the distribution of analytes between the enriched water layers on the surface of the mobile phase and the stationary phase, weak electrostatic interaction, hydrogen bond and molecular bipolar interaction, etc.
Based on ultra-high purity and porous spherical silica gel, Welch adopts unique stationary phase bonding technology and silica gel surface treatment technology, providing many HILIC chromatographic columns to meet the needs of different projects.
Ultisil® HILIC Amide column
Ultisil® HILIC Amide column is a special column designed for HILIC mode. As amide group has strong hydrophilicity, stability and electrically neutral, Ultisil® Amide has longer life, better reproducibility and more ideal peak shape than NH2 phase.
• Based on silica bonded with amide groups, appropriate for the separation of hydrophilic samples
• Multiple actions such as hydrogen bond, molecular and electrostatic interactions
• Good compatibility with many kinds of detectors, such as MS detector
• Stable in organic mobile phase that contains water
Ultisil® HILIC Amphion II Column
Ultisil® HILIC Amphion II is a newly developed HILIC column, using amphion-bonded silica as packing material. It applies to the separation of most polar compounds, using acetonitrile or Water other than ion-pairing reagents as mobile phase. The Amphion, containing both Positive Charge Centre and Negative Charge Centre, brings high retention for acid and alkaline compounds through ion-exchange mechanism. Compared with common HILIC packing materials like silica and amino groups, the Amphion-bonded packing material provides better reproducibility and stability.
• Amphion-bonded silica stationary phase
• Enhanced hydrophilic interaction brings higher retention for polar and hydrophilic compounds
• Different selectivity from common HILIC packing materials
• Simple mobile phase used for the separation of polar compounds
Ultisil® HILIC Silica Column
Ultisil® HILIC provides complementary selectivity relative to the reverse phase and preserves high polar compounds that can not be retained by traditional methods. Compared to that reverse phase separation uses a high proportion of aqueous phase to retain polar molecules, Ultisil®HILIC silica gel column uses a high volatile mobile phase (>80% organic phase), which is ideal for mass spectrometry and detection sensitivity.
• Unique chemical bonding technology makes the surface of HILIC stationary phase have high chemical stability and low stationary phase loss;
• Suitable for separating polar drugs, peptides, amino acids and other compounds.
If you have any problem or require further information, please contact info@welchmat.com.
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