title: Methods to Concentrate Proteins for Protein Isolation, Proteomic, and Peptidomic Evaluation.
abstract: In protein isolation, proteomic, or peptidomic procedures, protein solutions are often concentrated to remove solvents and undesirable molecules, to separate protein fractions or to increase protein concentrations. Proteins can be concentrated by precipitation from solution with ammonium sulfate, polyethylene glycol, organic solvent, trichloroacetic acid, potassium chloride/sodium dodecyl sulfate, and three-phase partitioning. Solvents can be removed by passage through a semipermeable barrier where protein solutions are forced against the barrier in a centrifuge tube or with increased pressure concentrating protein in the remaining solution. The semipermeable barrier can be surrounded by a hygroscopic reagent to draw the solvent across the membrane. Proteins can be concentrated by freeze-drying (lyophilization). All these methods to concentrate proteins are discussed.
authors.affiliation: Biochemistry, University of KwaZulu-Natal, Pietermaritzburg PBX01, Scottsville, 3209, South Africa, GoldringD@ukzn.ac.za.
authors.forename: J P Dean
authors.initials: JP
authors.lastname: Goldring
mesh_terms: D000327:Adsorption; D000645:Ammonium Sulfate / Q000737:chemistry; D000818:Animals; D002498:Centrifugation / Q000379:methods; D011232:Chemical Precipitation; D003956:Dialysis / Q000379:methods; D004591:Electrophoresis, Polyacrylamide Gel / Q000379:methods; D005612:Freeze Drying / Q000379:methods; D006801:Humans; D011092:Polyethylene Glycols; D011506:Proteins / Q000302:isolation & purification*; D040901:Proteomics / Q000379:methods; D012967:Sodium Dodecyl Sulfate / Q000737:chemistry; D012997:Solvents / Q000737:chemistry; D014238:Trichloroacetic Acid / Q000737:chemistry; D014462:Ultrafiltration / Q000379:methods
chemical_list: D011506:Proteins; D012997:Solvents; D012967:Sodium Dodecyl Sulfate; D011092:Polyethylene Glycols; D014238:Trichloroacetic Acid; C028913:dodecyl sulfate; D000645:Ammonium Sulfate