Dash R J, England B G, Midgley A R, Niswender G D
Steroids. 1975 Nov;26(5):647-61. doi: 10.1016/0039-128x(75)90057-4.
A radioimmunoassay technique has been developed for the measurement of cortisol in a single methylene chloride extract of human plasma without chromatography. The antiserum, obtained by immunizing rabbits with cortisol-3-carboxymethyl-oxime conjugated to bovine serum albumin, had a high affinity (KA = 1.8 X 10(9) 1/mole) and capacity (2.3 X 10(-6) moles/L undiluted serum) for cortisol. The minimum detectable amount determined at the lower 95% confidence limit of the buffer control tubes was 8.3 +/- 4.7 pg/tube and a log dose - logit response standard curve was linear between 20 pg and 20 ng/tube. The antiserum was highly specific for cortisol with only corticosterone, cortisone, 11-deoxycortisol and 21-deoxycortisol showing significant cross-reaction (12.4, 6.6, 3.8 and 3.7%, respectively). The cross-reaction for the other tested naturally occurring and synthetic steroids did not exceed 1%. Regression analysis of cortisol concentration estimates obtained on 20 samples before and after Sephadex LH-20 column chromatography gave a coefficient of correlation (r) of 0.995 and a regression coefficient (b) of 1.04. Recovery of cortisol added to plasma samples was quantitative. The intra-assay error was 8.5% and the inter-assay error averaged 5.7%. The method is simple requiring a single solvent extraction of plasma, therefore permitting large numbers of samples to be handled efficiently by a single technician.
已开发出一种放射免疫分析技术，用于在不进行色谱分析的情况下，测定人血浆二氯甲烷单次提取物中的皮质醇。通过用与牛血清白蛋白偶联的皮质醇 - 3 - 羧甲基肟免疫兔子获得的抗血清，对皮质醇具有高亲和力（KA = 1.8×10⁹ 1/摩尔）和容量（2.3×10⁻⁶摩尔/升未稀释血清）。在缓冲液对照管的95%置信下限处测定的最低可检测量为8.3±4.7皮克/管，并且在20皮克至20纳克/管之间，对数剂量 - 对数几率响应标准曲线呈线性。该抗血清对皮质醇具有高度特异性，仅皮质酮、可的松、11 - 脱氧皮质醇和21 - 脱氧皮质醇显示出显著的交叉反应（分别为12.4%、6.6%、3.8%和3.7%）。其他测试的天然存在和合成类固醇的交叉反应不超过1%。对20个样品在Sephadex LH - 20柱色谱前后获得的皮质醇浓度估计值进行回归分析，相关系数（r）为0.995，回归系数（b）为1.04。添加到血浆样品中的皮质醇回收率是定量的。批内误差为8.5%，批间误差平均为5.7%。该方法简单，只需对血浆进行单次溶剂萃取，因此允许一名技术人员高效地处理大量样品。
