title: Optimization of the capillary zone electrophoresis loading limit and resolution of proteins, using triethylamine, ammonium formate and acidic pH.
abstract: Capillary zone electrophoresis (CZE) of five model proteins (lysozyme, myoglobin, ribonuclease A, alpha-lactalbumin, and trypsinogen), using ammonium formate as the electrophoretic buffer and triethylamine (TEA) as a buffer additive at pH 2.5, was used for protein separation. The electrophoretic behavior of these proteins was examined with respect to various concentrations (10-40 mM) of TEA and of ammonium formate. Based on the experimental parameters of electrophoretic resolution, current, and peak separation time, an electrolyte (30 mM each of TEA and ammonium formate) was empirically derived as the optimum for scale-up separation. The loading limit for proteins, covering a wide range of injection volumes (60-990 nl) and amount of protein (1-21 pmol of each protein), was investigated on 75 and 100 microns I.D. untreated fused-silica capillaries. Protein adsorption (average < 15%) was experimentally determined using this volatile buffer system.
authors.affiliation: Charles B. Stout Neuroscience Mass Spectrometry Laboratory, University of Tennessee, Memphis 38163, USA.
authors.forename: H G
authors.initials: HG
authors.lastname: Lee
authors.forename: D M
authors.initials: DM
authors.lastname: Desiderio
mesh_terms: D000327:Adsorption; D000818:Animals; D002021:Buffers; D002417:Cattle; D002645:Chickens; D019075:Electrophoresis, Capillary / Q000379:methods*; D005021:Ethylamines; D005561:Formates; D006736:Horses; D006863:Hydrogen-Ion Concentration; D007202:Indicators and Reagents; D007526:Isoelectric Point; D007768:Lactalbumin / Q000302:isolation & purification; D008970:Molecular Weight; D009113:Muramidase / Q000302:isolation & purification; D009211:Myoglobin / Q000302:isolation & purification; D011506:Proteins / Q000302:isolation & purification*; D012259:Ribonuclease, Pancreatic / Q000302:isolation & purification; D014362:Trypsinogen / Q000302:isolation & purification
chemical_list: D002021:Buffers; D005021:Ethylamines; D005561:Formates; D007202:Indicators and Reagents; D009211:Myoglobin; D011506:Proteins; C030544:formic acid; D014362:Trypsinogen; D007768:Lactalbumin; D012259:Ribonuclease, Pancreatic; D009113:Muramidase; C016162:triethylamine