Silica hydride based phases for small molecule separations using automated liquid chromatography-mass spectrometry...

Area of Science:

• Analytical Chemistry
• Chromatography Science

Background:

• Silica hydride (Type C silica) is an emerging chromatographic support material.
• Various bonded phases are available for silica hydride supports.
• Understanding retention and selectivity is crucial for method development.

Purpose of the Study:

• To investigate the retention and selectivity behavior of four novel silica hydride bonded phases.
• To evaluate these phases under reversed-phase and aqueous normal-phase conditions.
• To identify potential for dual retention modes in liquid chromatography.

Main Methods:

• Liquid chromatography coupled with triple quadrupole mass spectrometry was employed.
• Four bonded phases (Cholesterol, Bidentate C18, Diamond Hydride, Diol) were screened.
• Automated column switching and scouting gradients were utilized for phase evaluation.

Main Results:

• Four analytes demonstrated dual-mode retention behavior across all tested phases.
• Fentanyl showed distinct "U-shaped" retention profiles on Cholesterol and Bidentate C18 phases.
• Retention order changes between reversed-phase and aqueous normal-phase highlighted altered selectivity, with Cholesterol phase offering highest retention.

Conclusions:

• Silica hydride bonded phases exhibit diverse retention and selectivity profiles.
• The potential for dual retention modes offers new possibilities for analyte separation.
• These novel phases provide reproducible retention and selectivity for liquid chromatography applications.