title: Effect of storage on the bioactivity of two international reference preparations of human pituitary luteinizing hormone in vitro.
abstract: There was no loss of biological activity in vitro when the 1st International Reference Preparation (IRP) for human pituitary gonadotrophins [FSH and LH/interstitial cell stimulating hormone (ICSH) for bioassay] code no. 69/104 and the 1st IRP for human pituitary LH/ICSH [for immunoassay] code no. 68/40 were stored for 1 year at -70 degrees C in a buffered 0.8% saline solution containing 1% bovine plasma albumin (BPA). However, storage of the 69/104 preparation at -20 degrees C in either 0.1 or 1% BPA, or at -70 degrees C in the presence of 0.1% BPA showed a small but significant decrease (approximately 10%) in activity over the same period. It is, therefore, advantageous to store these reference preparations at -70 degrees C in the presence of 1% BPA.
mesh_terms: D004356:Drug Storage; D005615:Freezing; D006801:Humans; D066298:In Vitro Techniques; D007986:Luteinizing Hormone / Q000378:metabolism / Q000592:standards*; D012015:Reference Standards
chemical_list: D007986:Luteinizing Hormone