Introducing Hydrofluoroethers as Modifiers for Enantioseparation in Super/Subcritical Fluid Chromatography.

Area of Science:

• Analytical Chemistry
• Chromatography

Background:

• Super/subcritical fluid chromatography (SFC) is a powerful separation technique.
• Conventional modifiers in SFC can limit the accessible chemical space and achievable selectivity.
• There is a need for novel modifiers to expand SFC capabilities, particularly for challenging separations like enantioseparations.

Purpose of the Study:

• To introduce and evaluate hydrofluoroethers, termed Engineered Fluids, as novel modifiers in SFC.
• To investigate the utility of Engineered Fluids for enantioseparations on polysaccharide-based chiral stationary phases.
• To demonstrate the unique selectivity offered by Engineered Fluids compared to conventional solvents.

Main Methods:

• Utilized three hydrofluoroethers (Novec 7000, 7100, 7200) as modifiers in SFC.
• Employed polysaccharide-based chiral stationary phases (Chiralpak AD and IG).
• Analyzed enantioseparations using super/subcritical fluid chromatographic conditions with varying Engineered Fluid concentrations blended with methanol.

Main Results:

• Engineered Fluids provided novel selectivity for enantioseparations, not achievable with conventional modifiers like neat methanol.
• Enhanced retention and significant selectivity changes were observed when Engineered Fluids were blended with methanol.
• Optimization of Engineered Fluid concentration in the mobile phase was found to be crucial for maximizing separation performance.
• Different hydrofluoroethers within the Engineered Fluids class exhibited distinct selectivity profiles, highlighting their tunable nature.

Conclusions:

• Hydrofluoroethers (Engineered Fluids) represent a new class of effective modifiers for SFC.
• These novel modifiers significantly expand the chemical space and selectivity options for chiral separations.
• Engineered Fluids offer a promising alternative to conventional solvents for achieving unique enantioseparations in SFC.