Ethylbenzene-modified fused-silica columns for capillary electrophoresis
Coated capillaries modified with a hydrocarbon layer have been developed. Modification of the surface with ethylbenzene greatly improved the electrophoretic performance of the capillaries. The column efficiency for basic organic compounds was as high as 378000 theoretical plates per meter on a 50 μm i.d. ethylbenzene-surface-treated fused-silica capillary column. This value did not change during 25 replicate analyses and the capillary columns were very stable against continuous treatment for 30 h with buffer of pH 10 and treatment for 3 h with HCl of pH 1 and NaOH of pH 12. The relative standard deviation of run-to-run, day-to-day, and capillary-to-capillary for coating with the ethylbenzene layer was<2.6%, and reproducibility was good. The separation of four aromatic amines and six pharmacological amines at pH 2.5 is reported.
Key WordsCapillary electrophoresis Surface modification Ethylbenzene coating Ethylbenzene-n-hydrocarbon coating Basic organic compounds
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- Adamson, A.W.Physical Chemistry of Surfaces, 4th edn, Wiley, New York,1982.Google Scholar
- Bard, A.; Faulkner, L.Electrochemical Methods: Fundamentals and Applications, Wiley, NY,1980.Google Scholar
- Morrison, R.T.; Boyd, R.N.Chimica Organica, 5th edn, Casa Editrice Ambrosiana, Milano,1991.Google Scholar
- Vogel, A.I.Chimica Organica Pratica, 3rd edn, Casa Editrice Ambrosiana, Milano,1967.Google Scholar
- Jorgenson, J.W.; Lukacs, K.D.Anal. Chem. 1981,53, 1298.Google Scholar