Capillary electrophoretic resolution of phosphorylated peptide isomers using micellar solutions and coated capillaries.
The addition of sodium dodecyl sulfate (SDS) micelles in the running buffer can be used to resolve mono- and diphosphorylated isomers of the insulin receptor peptide by capillary electrophoresis. The effect of SDS on peptide resolution is very dependent on pH. Complete resolution of three monophosphorylated isomers is achieved in uncoated capillaries filled with phosphate buffer containing 25 mM SDS and buffered at pH 6.1. Resolution of the diphosphorylated isomers can be significantly improved by using polyacrylamide coated capillaries. In coated capillaries electroosmotic flow is negligible and the migration order of the isomers is reversed. This allows for a longer period of interaction between the diphosphorylated isomers and the micelle and therefore selectivity is improved. Efficiency of all peptide isomers was also improved in coated capillaries due to reduced adsorption to the capillary wall.
Tadey
T
T
Department of Chemistry, McGill University, Montreal, Quebec, Canada.
Purdy
W C
WC
D000180:Acrylic Resins / Q000737:chemistry; D000595:Amino Acid Sequence; D002845:Chromatography / Q000379:methods*; D004586:Electrophoresis / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D008823:Micelles; D008969:Molecular Sequence Data; D010455:Peptides / Q000032:analysis; D010766:Phosphorylation; D011972:Receptor, Insulin / Q000032:analysis* / Q000737:chemistry; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D000099166:Polyacrylamides
D000180:Acrylic Resins; D008823:Micelles; D010455:Peptides; D011972:Receptor, Insulin; D012967:Sodium Dodecyl Sulfate; D000099166:Polyacrylamides