Several earlier investigations have focused on enantiomeric binding sites on
chiral selectors (Domenici et al. 1990; Noctor et al. 1992). In these studies, an
immobilised-selector stationary phase was initially equilibrated with a mobile
phase containing a single enantiomer. The retention of the other enantiomeric solute
injected onto the column under these conditions was then compared with the
retention of the solute when no enantiomer is dissolved in the mobile phase. If the
enantiomers bind at the same location(s), the retention of the injected enantiomer
will be decreased by the presence of the equilibrated enantiomer within the stationary phase. Moreover, if the column is equilibrated with a series of marker solutes that
are known to bind at specific sites on the selector, the precise location of the binding
site for each enantiomer can be systematically determined. Although in many cases,
the structure of these binding sites remains ambiguous, the information gained from
these studies is valuable when used in conjunction with other structural or
functional data.
3.8 Updated Reviews on Enantioselective HPLC/UHPLC
New updated reviews reported advancements in enantiomer-selective HPLC/
UHPLC after the first edition of this monograph was published. These overviews
are recommended for more detailed overviews on specific topics with regard to
current applications of HPLC/UHPLC in analytical chemistry and environmental
research (Turiel and Martin-Esteban 2004; Wong 2006; Mericko et al. 2007; PerezFernandez et al. 2011; Nie et al. 2013; Leon-Gonzalez et al. 2014; Lorenz and
Seidel-Morgenstern 2014; Tiwari and Prasad 2015; Pan et al. 2016; Patel et al. 2016;
Scriba 2016; Sanganyado et al. 2017; Greno et al. 2018; Huang et al. 2018a; Ribeiro
et al. 2018) (Table 3.4).
Table 3.3 Principal Thermodynamic functions related to chromatographic separation
Parameter
Unit [SI]
property
Energy (E)
J
Intermolecular forces
Gibbs free energy (ΔG)
ΔG ¼ ΔH – TΔS
J mol
–1
Energy loss during chemical/physical
transition
Enthalpy (ΔH )
ΔH ¼ ΔU + PΔV
J mol
–1
Energy transition during chromatographic
interactions
Entropy (ΔS)
ΔS ¼ q/T
J mol
–1 K
–1
Randomness movements along the chromatographic column
Compound specific distribution
coefficient
[A] s /[A] m
Dimensionless Chromatographic interactions
3.8 Updated Reviews on Enantioselective HPLC/UHPLC
47
chiral selectors (Domenici et al. 1990; Noctor et al. 1992). In these studies, an
immobilised-selector stationary phase was initially equilibrated with a mobile
phase containing a single enantiomer. The retention of the other enantiomeric solute
injected onto the column under these conditions was then compared with the
retention of the solute when no enantiomer is dissolved in the mobile phase. If the
enantiomers bind at the same location(s), the retention of the injected enantiomer
will be decreased by the presence of the equilibrated enantiomer within the stationary phase. Moreover, if the column is equilibrated with a series of marker solutes that
are known to bind at specific sites on the selector, the precise location of the binding
site for each enantiomer can be systematically determined. Although in many cases,
the structure of these binding sites remains ambiguous, the information gained from
these studies is valuable when used in conjunction with other structural or
functional data.
3.8 Updated Reviews on Enantioselective HPLC/UHPLC
New updated reviews reported advancements in enantiomer-selective HPLC/
UHPLC after the first edition of this monograph was published. These overviews
are recommended for more detailed overviews on specific topics with regard to
current applications of HPLC/UHPLC in analytical chemistry and environmental
research (Turiel and Martin-Esteban 2004; Wong 2006; Mericko et al. 2007; PerezFernandez et al. 2011; Nie et al. 2013; Leon-Gonzalez et al. 2014; Lorenz and
Seidel-Morgenstern 2014; Tiwari and Prasad 2015; Pan et al. 2016; Patel et al. 2016;
Scriba 2016; Sanganyado et al. 2017; Greno et al. 2018; Huang et al. 2018a; Ribeiro
et al. 2018) (Table 3.4).
Table 3.3 Principal Thermodynamic functions related to chromatographic separation
Parameter
Unit [SI]
property
Energy (E)
J
Intermolecular forces
Gibbs free energy (ΔG)
ΔG ¼ ΔH – TΔS
J mol
–1
Energy loss during chemical/physical
transition
Enthalpy (ΔH )
ΔH ¼ ΔU + PΔV
J mol
–1
Energy transition during chromatographic
interactions
Entropy (ΔS)
ΔS ¼ q/T
J mol
–1 K
–1
Randomness movements along the chromatographic column
Compound specific distribution
coefficient
[A] s /[A] m
Dimensionless Chromatographic interactions
3.8 Updated Reviews on Enantioselective HPLC/UHPLC
47