RADIOIMMUNOASSAY FOR STEROID HORMONES I. RADIOIMMUNOASSAY FOR PLASMA CORTISOL
A radioimmunoassay for the measurement of plasma cortisol has been developed. Antiserum raised against cortisol-21-hemisuccinate conjugated to BSA has a high specificity for cortisol. A useful range in a dose response line ranges from 10 pg to 500 pg. 0.002 ml of plasma is used for the measurement without chromatography. The coeffecient of variation for within assay and between assay is 8.4 % and 7.0 % in average. The method is sensitive and precise for practical use.