el-Gamal B A, Landon J
Department of Chemical Pathology, St. Bartholomew's Hospital, London, UK.
Clin Chim Acta. 1988 Apr 15;173(2):201-16. doi: 10.1016/0009-8981(88)90258-6.
Separation techniques have been studied in the development of a direct radioimmunoassay to determine levels of 17-hydroxyprogesterone in serum. The same highly specific sheep antiserum was used throughout, together with the same amount of 125I-labelled 17-hydroxyprogesterone to which was added sodium salicylate to eliminate interference by endogenous binding proteins in serum samples. In one approach, dextran-coated charcoal was employed to adsorb the free fraction and, in another, the antibodies were covalently coupled to magnetisable particles. The antiserum was also adsorbed to assay tubes either directly or indirectly through second (double) antibodies. Analytical recovery and specificity were similar irrespective of the separation technique as was the correlation with results obtained by a reference assay. Levels of 17-hydroxyprogesterone in sera from normal adults and from treated and untreated patients with congenital adrenal hyperplasia due to 21-hydroxylase deficiency were also similar. However, the assay employing dextran-coated charcoal for separation showed the best precision and resulted in the greatest sensitivity, while the use of antibodies adsorbed indirectly to assay tubes was superior in terms of practicability.
在开发一种直接放射免疫测定法以测定血清中17-羟孕酮水平的过程中，对分离技术进行了研究。整个过程中使用的是同一种高特异性的绵羊抗血清，以及相同量的125I标记的17-羟孕酮，其中添加了水杨酸钠以消除血清样本中内源性结合蛋白的干扰。在一种方法中，使用葡聚糖包被的活性炭吸附游离部分，在另一种方法中，抗体与可磁化颗粒共价偶联。抗血清也可直接或通过第二（双）抗体间接吸附到测定管上。无论采用何种分离技术，分析回收率和特异性均相似，与参考测定法获得的结果的相关性也相似。正常成年人以及患有因21-羟化酶缺乏导致的先天性肾上腺皮质增生的经治疗和未经治疗患者的血清中17-羟孕酮水平也相似。然而，采用葡聚糖包被的活性炭进行分离的测定法显示出最佳的精密度并具有最高的灵敏度，而间接将抗体吸附到测定管上在实用性方面更具优势。
