Preparation and development of solid phase radioimmunoassay system for determination of cortisol

The goal of this article was oriented to prepare stable polystyrene coated tubes for direct radioimmunoassay (RIA) of human cortisol. Coating process was performed using rabbit polyclonal antisera specific for cortisol. The stability study showed that these tubes could be stored for up to one year at 4ºC without any appreciable reduction in their binding. Labeling of cortisol was carried out using chloramin-T method and the ¹²⁵I-cortisol tracer was purified using HPLC column. Preparation of polyclonal antibodies (anti-cortisol) was carried out in host rabbit animals against cortisol-21-hemisuccinate:Bovine serum albumin conjugate. The statistical analysis revealed good correlations between the results from the present study and the commercial IZOTOP RIA kit. The local may be extremely helpful in diagnosis and proper management of adrenal cortex disorders.