title: The effect of sample salt additives on capillary electrophoresis analysis of intact proteins using surface modified capillaries.
abstract: The effect of adding alkali salts to protein samples for capillary electrophoretic (CE) analysis of intact proteins was studied. A high degree of peak stacking, even for large proteins, was found to occur when alkali salts were added to the sample. The addition of salt to the protein sample promotes a strong improvement in the peak efficiency of individual proteins giving up to 2.1x 10(6)apparent plates/m. The concentration of salt required in the sample to reach optimal peak efficiency show dependency on both the molecular weight and molar concentration of the protein. However, adding salt will, at a sufficiently high concentration, cause a mixture of proteins to co-migrate to one very sharp peak. The observed sample stacking effect was obtained with a number of different surface modified silica capillaries indicating a general phenomenon and not surface coating specific.
authors.affiliation: Department of Physical and Analytical Chemistry, Uppsala University, Biomedical Center, Uppsala, Sweden.
authors.forename: Anisa
authors.initials: A
authors.lastname: Elhamili
authors.forename: Magnus
authors.initials: M
authors.lastname: Wetterhall
authors.forename: Angel
authors.initials: A
authors.lastname: Puerta
authors.forename: Douglas
authors.initials: D
authors.lastname: Westerlund
authors.forename: Jonas
authors.initials: J
authors.lastname: Bergquist
mesh_terms: D019075:Electrophoresis, Capillary / Q000295:instrumentation / Q000379:methods*; D011189:Potassium Chloride / Q000737:chemistry; D011506:Proteins / Q000032:analysis* / Q000737:chemistry; D012492:Salts / Q000737:chemistry*; D012680:Sensitivity and Specificity; D012822:Silicon Dioxide / Q000737:chemistry; D012965:Sodium Chloride / Q000737:chemistry; D012974:Sodium Iodide / Q000737:chemistry; D013499:Surface Properties
chemical_list: D011506:Proteins; D012492:Salts; D012965:Sodium Chloride; D011189:Potassium Chloride; D012822:Silicon Dioxide; D012974:Sodium Iodide