SIMULTANEOUS DETERMINATION OF IONIZATION-CONSTANTS AND ISOELECTRIC POINTS OF 12 HYDROXY-S-TRIAZINES BY CAPILLARY ZONE ELECTROPHORESIS AND CAPILLARY ISOELECTRIC-FOCUSING
P. Schmitt et al., SIMULTANEOUS DETERMINATION OF IONIZATION-CONSTANTS AND ISOELECTRIC POINTS OF 12 HYDROXY-S-TRIAZINES BY CAPILLARY ZONE ELECTROPHORESIS AND CAPILLARY ISOELECTRIC-FOCUSING, Analytical chemistry, 69(13), 1997, pp. 2559-2566
Capillary zone electrophoresis (CZE) was used to separate and determin
e simultaneously the pK(1), pK(2), and pI values of 12 environmentally
relevant hydroxytriazines (hydroxymetabolites of atrazine, terbuthyla
zine, simazine, and propazine and four (arylamino)-s-triazines) and ob
serve the effects of the alkylamino and arylamino substituents on the
measured values, Capillary isoelectric focusing (CIEF) methods were de
veloped to measure the pI of these compounds and compare those values
with the CZE-measured pI,s. CZE and CIEF can provide accurate pK and p
I values reasonably fast, and pI values measured by the two techniques
agree. Knowledge of the pK and pI values of hydroxytriazines is impor
tant for an understanding of the binding mechanisms of these molecules
in environmental matrices, Because the hydroxytriazines may exist as
a myriad of species-neutral, charged, zwitterionic, and keto-enol taut
omeric-depending on structure and pH, we briefly addressed the existen
ce of these species relative to their electrophoretic analysis.