10.1021/ac0498718.s001
Scott T. Burns
Scott T.
Burns
Morteza G. Khaledi
Morteza G.
Khaledi
Predictions of Micelle−Water Partition Coefficients
and Retention in Micellar Electrokinetic
Chromatography from Solute Structure. 2.
Fragmental Constant Approach
American Chemical Society
2004
K mw values
micelle partition coefficients
fragmental
fragment
198 aliphatic compounds
partition coefficients
prediction
LSER partition coefficient values
micellar electrokinetic chromatography
solute
log K mw
FCA
K mw φ
K mw
solvation energy relationship
MEKC
k i C m
Micellar Electrokinetic Chromatography
SDS
i f i
2004-09-15 00:00:00
Journal contribution
https://acs.figshare.com/articles/journal_contribution/Predictions_of_Micelle_Water_Partition_Coefficients_and_Retention_in_Micellar_Electrokinetic_Chromatography_from_Solute_Structure_2_Fragmental_Constant_Approach/3325144
The fragmental constant approach (FCA) was used to
calculate water−sodium dodecyl sulfate (SDS) micelle
partition coefficients, <i>K</i><sub>mw</sub>, for uncharged solutes from
their structure. Subsequently, the availability of <i>K</i><sub>mw</sub>
values allows prediction of retention factor, <i>k</i>, in micellar
electrokinetic chromatography (MEKC) using the simple
relationship <i>k = K</i><sub>mw</sub><i>φ</i>, where φ is the phase ratio. The
FCA model describes a micelle−water partition coefficient
as the sum of the partition coefficients of the constituent
atomic/molecular fragments, measured by fragmental
constant values, <i>f</i><i> </i><i><sub>i</sub></i>, as well as correction factors to account
for various “intramolecular effects” that cause deviations
from the predicted partition coefficients as, log <i>K</i><sub>mw</sub> =
<i>a</i><i><sub>i</sub></i><i>f</i><i> </i><i><sub>i</sub></i> +
<i>k</i><i><sub>i</sub></i><i>C</i><sub>m</sub>. The fragmental constants for a set of
41 fragments were determined using a training set of 229
aromatic solutes and 198 aliphatic compounds. The <i>K</i><sub>mw</sub>
of the aromatic compounds in the training set were
determined by MEKC, while the <i>K</i><sub>mw</sub> of the aliphatic
solutes were estimated using the linear solvation energy
relationship (LSER) for the SDS micelles. The fragments
consisted of both aromatic fragments (i.e., directly attached to an aromatic ring) and aliphatic fragments. The
FCA predictions agree nicely with the observed and LSER
partition coefficient values, even for complex molecular
structures such as β-blocker drugs. The results show the
great potential of the FCA for a priori prediction of
retention behavior in MEKC from solute structure.