Separation of peptides by open-tubular capillary electrochromatography using Fe(III)-deuteroporphyrin as a covalently attached stationary phase

YONE A; CARBALLO R; REZZANO IN; VIZIOLI NM*

ELECTROPHORESIS

WILEY-VCH

Lugar: Weinheim; Año: 2009 vol. 30 p. 2293 - 2299

0173-0835

The separation of seven biologically active peptides was attempted by open-tubular capillary electrochromatography (OT-CEC) in fused-silica (FS) capillaries chemically modified with Fe(III)-deuteroporphyrin using UV-absorption detection at 214 nm. The effect of background electrolyte (BGE) pH and content of organic solvent modifier was investigated. The best separations were obtained in 25 mM phosphate (BGE), pH 4.0, containing 5% v/v acetonitrile and 10 mM hydroquinone, which was added to prevent gas bubble formation. Considering the method sensitivity, lower concentration LODs were obtained for all peptides in their OT-CEC separation as compared to their CZE separation in bare FS capillary. The Fe(III)-deuteroporphyrin column proved to be highly stable over time and showed acceptable precision of migration times and corrected peak areas (RSD in the range 2 - 4 %).