title: Use of electrophoresis and gel filtration to characterize human pituitary somatotropin preparations after storage.
abstract: Fresh and stored preparations of human pituitary somatotropin examined by different polyacrylamide gel electrophoresis techniques and by gel exclusion chromatography (Ultrogel) clearly demonstrated that the hormone undergoes a structural alteration during storage for 3 years. The formed aggregates were readily quantitated from the gel filtration profile and from polyacrylamide gel electrophoresis in the presence of sodium dodecylsulfate (SDS-PAGE). According to gel filtration the amount of aggregates in fresh and stored hormone was determined to be 2 and 10%, respectively, while SDS-PAGE indicated 6 and 14%.
mesh_terms: D002850:Chromatography, Gel; D004591:Electrophoresis, Polyacrylamide Gel; D013006:Growth Hormone / Q000032:analysis*; D006801:Humans; D007525:Isoelectric Focusing; D008968:Molecular Conformation; D008970:Molecular Weight; D011092:Polyethylene Glycols; D011309:Preservation, Biological; D013997:Time Factors
chemical_list: D011092:Polyethylene Glycols; D013006:Growth Hormone