Covalent anionic copolymer coatings with tunable electroosmotic flow for optimization of capillary electrophoretic separations

0561238 - ÚOCHB 2023 RIV DE eng J - Journal Article
Šolínová, Veronika - Tůma, P. - Butnariu, Maria - Kašička, Václav - Koval, Dušan
Covalent anionic copolymer coatings with tunable electroosmotic flow for optimization of capillary electrophoretic separations.
Electrophoresis. Roč. 43, č. 20 (2022), s. 1953-1962. ISSN 0173-0835. E-ISSN 1522-2683
R&D Projects: GA ČR(CZ) GA20-03899S
Institutional support: RVO:61388963
Keywords : capillary coating * capillary electrophoresis * electroosmotic flow * chiral separation * helicene
OECD category: Analytical chemistry
Impact factor: 2.9, year: 2022
Method of publishing: Limited access
https://doi.org/10.1002/elps.202200130

We present a method for finely adjustable electroosmotic flow (EOF) velocity in cathodic direction for the optimization of separations in capillary electrophoresis. To this end, we use surface modification of the separation fused silica capillary by the covalently attached copolymer of acrylamide (AM) and 2-acrylamido-2-methyl-1-propanesulfonate (AMPS), that is, poly(AM-co-AMPS) or PAMAMPS. Coatings were formed by the in-capillary polymerization of a mixture of the neutral AM and anionic AMPS monomers premixed in various ratios in order to control the charge density of the copolymer. EOF mobility varies in the 0 to similar to 40 x 10(-9) m(2) V-1 s(-1) interval for PAMAMPS coatings ranging from 0 to 60 mol.% of charged AMPS monomer. For EOF in PAMAMPS-treated capillaries, we observed (i) a negligible dependence on pH in the 2-10 interval, (ii) a minor variance among background electrolytes (BGEs) in function of their components and (iii) its standard decrease with increasing ionic strength of the BGE. Interest in variable cathodic EOF was demonstrated by the amelioration of separation of two kinds of isomeric anionic analytes, that is, monosaccharides phosphates and helquat enantiomers, in counter-EOF mode.
Permanent Link: https://hdl.handle.net/11104/0333923