Morineau G, Gosling J, Patricot M C, Soliman H, Boudou P, al Halnak A, Le Brun G, Brérault J L, Julien R, Villette J M, Fiet J
Laboratoire de Biologie Hormonale, Hôpital Saint-Louis, Paris, France.
Clin Chem. 1997 May;43(5):786-93.
We applied various prepurification protocols (extraction with different solvents, liquid/solid separation on bonded silica media, Celite, and Sephadex LH20 chromatography) with a range of commercially available RIA kits to measure cortisol in urine samples. We then compared the results with the concentrations measured by a HPLC method validated with reference to isotope dilution gas chromatography-mass spectrometry. We conclude that chromatography on a commercial, prepacked diol minicolumn (Waters Sep-Pak Vac RC) in combination with dichloromethane extraction is a convenient and very effective purification step before RIA of urinary cortisol in patients not receiving corticoid medication. We tested numerous steroids for interference and found that free polar cortisol derivatives (hydroxylated or hydrogenated) could only partially account for the overestimations routinely encountered when free urinary cortisol concentrations are measured by direct RIA.
我们使用多种预纯化方案（用不同溶剂萃取、在键合硅胶介质、硅藻土和葡聚糖凝胶LH20上进行液/固分离、以及进行色谱分析），搭配一系列市售放射免疫分析试剂盒，来测定尿液样本中的皮质醇。然后，我们将结果与通过参考同位素稀释气相色谱-质谱法验证的高效液相色谱法所测得的浓度进行比较。我们得出结论，对于未接受皮质类固醇药物治疗的患者，在对尿皮质醇进行放射免疫分析之前，使用市售的预填充二醇微型柱（Waters Sep-Pak Vac RC）进行色谱分析并结合二氯甲烷萃取，是一个方便且非常有效的纯化步骤。我们测试了多种类固醇的干扰情况，发现游离极性皮质醇衍生物（羟基化或氢化）只能部分解释在通过直接放射免疫分析测定游离尿皮质醇浓度时经常出现的高估现象。
