Performance of amino‐silylated fused‐silica capillaries for the separation of enkephalin‐related peptides by capillary zone electrophoresis and micellar electrokinetic chromatography
- 1 January 1995
- journal article
- research article
- Published by Wiley in Electrophoresis
- Vol. 16 (1), 557-563
- https://doi.org/10.1002/elps.1150160191
Abstract
Enkephalin-related peptides were separated at low pH in a capillary with covalently bonded aminopropyl groups. The peptides are electrostatically repelled from the capillary surface and much higher efficiencies and faster separations were achieved compared to separations using uncoated capillaries. At low pH the amino groups are protonated, which results in reversed electroosmosis. The influence of voltage and ionic strength on the mobility and the separation efficiency was studied. The repeatability of migration times within one day was very good with relative standard deviations of 0.3–0.7%. Increasing the pH decreased the electroosmosis, eventually turning towards the cathode in the pH range 5–6; the separation performance, however, was lower at higher pH. Neutral and anionic micellar agents were added to the background electrolyte at different concentrations; the enkephalins had weak association with the neutral micellar agents but were distributed to the anionic taurodeoxycholic acid (TDC) micelles, giving rise to changes in separation selectivities. Very high efficiencies were obtained for peptides with a low distribution to the TDC micelles, while the efficiencies were impaired for those with a strong association with the micelles, which may indicate a slow mass transfer in the association process.Keywords
This publication has 20 references indexed in Scilit:
- A new type of pH‐ and detergent‐stable coating for elimination of electroendosmosis and adsorption in (capillary) electrophoresisElectrophoresis, 1993
- Electrophoretic separations of proteins in capillaries with hydrolytically-stable surface structuresAnalytical Chemistry, 1990
- Performance of carbohydrate-modified fused-silica capillaries for the separation of proteins by zone electrophoresisJournal of Chromatography A, 1989
- Capillary electrophoresis of proteins in buffers containing high concentrations of zwitterionic saltsJournal of Chromatography A, 1989
- Capillary zone electrophoretic separations of proteins in polyethylene glycol-modified capillariesJournal of Chromatography A, 1989
- Capillary zone electrophoretic separation of peptides and proteins using low pH buffers in modified silica capillariesAnalytical Chemistry, 1988
- High voltage capillary zone electrophoresis: Operating parameters effects on electroendosmotic flows and electrophoretic mobilitiesChromatographia, 1987
- Control of electroosmosis in coated quartz capillariesJournal of Colloid and Interface Science, 1987
- Capillary zone electrophoresis of proteins in untreated fused silica tubingAnalytical Chemistry, 1986
- High-performance electrophoresisJournal of Chromatography A, 1985