H. Wan et al., Chemometric modeling of neurotransmitter amino acid separation in normal and reversed migration micellar electrokinetic chromatography, J CHROMAT A, 916(1-2), 2001, pp. 255-263
A chemometric experimental design has been applied for the optimization of
neurotransmitter amino acid separation in capillary electrophoresis. The op
timizations were carried out for normal micellar electrokinetic chromatogra
phy (N-MEKC) and reversed migration micellar electrokinetic chromatography
(RM-MEKC). In order to optimize three separation factors and study the inte
raction between factors, a response function was optimized via searching it
s optimum (minimum/maximum). Far this purpose a central composite design wi
th multivariate linear regression (MLR) analysis was utilized. Modeling wit
h good regression coefficients from the MLR adequately described the intera
ction of factors such as background electrolyte and sodium dodecylsulfate c
oncentrations which had a large impact on selectivity and migration behavio
rs. Similar optimal conditions regarding resolution and number of theoretic
al plates but different retention behaviors as a function of background ele
ctrolyte and micellar concentrations were observed for N-MEKC and RM-MEKC.
Improved overall performance from the RM -MEKC separation of five neurotran
smitter acids, superior to N-MEKC, is demonstrated in terms of repeatabilit
y, peak symmetry, sensitivity, and in particular, impurity determination in
an overloaded separation system. (C) 2001 Elsevier Science B.V. All rights
reserved.