Determination of Corticoids using Pyrrole. IV. Fluorometric Determination of Cortisol in Serum

Abstract

A fluorometric method for the determination of cortisol (CS) in serum was established. The keto-alcohol side-chain of CS was converted to keto-aldehyde with cupric acetate, and the product was reacted with pyrrole. The relationship between the fluorescence intensity and the concentration of CS was linear in the range of 0-50 ng. This method was applied to the determination of human serum CS and the analytical data were compared with those obtained by radioimmunoassay. The regression equation for the results of the two method was y=1.29x-0.44, and the coefficient of correlation for 14 samples with CS in the range of 6.78-14.56 μg/dl was 0.967. This method gave reliable results with high specificity and sensitivity.