Jp. Quirino et S. Terabe, Sweeping of neutral analytes via complexation with borate in capillary zone electrophoresis, CHROMATOGR, 53(5-6), 2001, pp. 285-289
The sweeping concept is extended to capillary zone electrophoresis (CZE) se
paration of neutral solutes involving complexation with berate. Analogous i
o the pseudostationary phase in electrokinetic chromatography (EKC), the co
mplexing agent (borate) serves as carrier for sweeping and separation in CZ
E. Therefore, similar to the retention factor in EKC, the focusing effect i
n the present system is directly related io the association constant betwee
n the analyte and complexing agent. Theoretical and some preliminary experi
mental studies generally suggest that the electrophoretic mobility of the c
omplex and the concentration of the complexing agent affect the resulting l
ength of narrowed zones. Moreover, sweeping using berate is affected by pH
since borate complexation is pH dependent. From around 10 to 40-fold improv
ement in peak heights has been observed experimentally for some neutral les
t analytes (monosaccharides, catechols, and nucleosides)