H. Cottet et P. Gareil, ELECTROPHORETIC BEHAVIOR OF FULLY SULFONATED POLYSTYRENES IN CAPILLARIES FILLED WITH ENTANGLED POLYMER-SOLUTIONS, Journal of chromatography, 772(1-2), 1997, pp. 369-384
Citations number
25
Categorie Soggetti
Chemistry Analytical","Biochemical Research Methods
Very little work has been reported so far on the separation of synthet
ic or industrial polyelectrolytes by CE. Following the pioneering work
by Poll and Schure (Anal. Chem., 64 (1992) 896), a more extensive stu
dy was undertaken on the separation of standard sodium polystyrenesulf
onates (PSS), with molecular masses ranging between 16 and 990x10(3),
in capillaries filled with entangled hydroxyethylcellulose (HEC, M-r 2
50x10(3)) or polyethyleneoxide (PEG, M-r 100x10(3)) solutions as sievi
ng media. Both bare and polyethyleneglycol (PEG) coated silica capilla
ries were successfully carried out for achieving the separation. As a
consequence, the detection order was easily inverted. Nevertheless, PE
G-coated capillaries should not be used in conjunction with chemically
similar PEO solutions, owing to PSS-PEG interactions. In order to ana
lyze the electrophoretic behaviour of PSS in these polymer solutions,
viscosity measurements directly performed using the CE instrument enab
led us to estimate some characteristic polymer parameters such as the
radii of gyration, monomer dimensions, entanglement thresholds as well
as average pore sizes of the separating network. The influence of the
nature and concentration of the separating polymer, the nature of the
buffer counter-ion, the ionic strength and the field strength are pre
sented in detail. The PSS migration regimes are also analyzed on the b
asis of classical models (Ogston, modified Ogston, reptation, biased r
eptation) that were initially established to account for DNA migration
in permanent gels. The impact of PSS molecular masses and conformatio
n and of network pore size is highlighted.