Non-Separation Radioassay for Cortisol Binding Capacity in Human Serum

Abstract

i Summary: A radioassay for the measurement of cortisol binding capacity in human serum was developed and the results validated by radioimmuiioassay of serum corticosteroid binding globulin. The mini-scale method is simple, reliable and rapid, and avoids Separation of partitioned phases. The linear correlation between the free cortisol index and free cortisol concentration äs calculated by the two methods utilizing serum samples with normal and abnormal protein concentrations was r = 0.962 (n = 114, p < 0.001) and the regression equation was y = 3.51 6 -2.632. The teehnique requires no preparation of reagents, and the assay can be performed in 45 minutes using 0.05 ml of serum or plasma.