Stability of four steroids in lyophilised human serum.
The stability of a preparation of lyophilised serum and its suitability for use as a reference material for routine assays of cortisol, oestradiol, and progesterone have been studied in four laboratories with a variety of assay systems. Cortisol and oestradiol were also measured by gas chromatography-mass spectrometry. The lyophilised serum was suitable for use in all routine and reference assay methods examined, with between-method variability no greater than that for frozen serum pools. The concentrations of cortisol, oestradiol, and progesterone were predicted by accelerated degradation studies to decline by 0.01% per annum if the preparations were to be stored at --20 degrees C. The testosterone content of the preparation, determined in one laboratory, provided no evidence for degradation. The preparation can be shipped for use at ambient temperature without deleterious effect.
D004355:Drug Stability; D004958:Estradiol / Q000097:blood*; D005260:Female; D005612:Freeze Drying; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D008598:Menstruation; D011374:Progesterone / Q000097:blood*; D013048:Specimen Handling; D013696:Temperature; D013739:Testosterone / Q000097:blood*; D013997:Time Factors
D013739:Testosterone; D011374:Progesterone; D004958:Estradiol; D006854:Hydrocortisone