Flow-injection chemiluminometric analysis of some steroids by their sensitizing effect on the bromate-sulphite reaction

The chemiluminescent oxidation of sulphite by bromate was investigated and compared with that by cerium(IV). The reaction is sensitized by various steroid hormones which can thus be determined in the ranges 0.50–20.0μg ml ¹ for cortisone; 0.50–5.00 μg ml^?1 for hydrocortisone and progesterone and 0.50–6.00 μg ml^?1 for testosterone and corticosterone.     

Surface plasmon resonance immunosensor for cortisol and cortisone determination

In this paper, we present a surface-plasmon-resonance-based immunosensor for the real-time detection of cortisol and cortisone levels in urine and saliva samples. The method proposed here is simple, rapid, economic, sensitive, robust, and reproducible thanks also to the special features of the polycarboxylate-hydrogel-based coatings used for the antibody immobilization. The sensor surface displays a high level of stability during repeated regeneration and affinity reaction cycles. The immunosensor shows high specificity for cortisol and cortisone; furthermore, no significant interferences from other steroids with a similar chemical structure have been observed. The suitability of the hydrogel coating for the prevention of nonspecific binding is also investigated. A good correlation is noticed between the results obtained by the proposed method and the reference liquid chromatography/tandem mass spectrometry method for the analysis of cortisol and cortisone in urine and saliva samples. Standard curves for the detection of cortisol and cortisone in saliva and urine are characterized by a detection limit less than 10 μg l⁻¹, sufficiently sensitive for both clinical and forensic use. Application of a newly developed SPR immunosensor for the measurement of cortisol in anti-doping analysis     

Spectrophotometric Determination of δ4 -3-Ketosteroids Using Oxalyldihydrazide

Abstract

A novel spectrophotometric method for the assay of δ⁴ -3-Ketosteroids in formulations is presented. Oxalyldihydrazide in methanol reacts selectively with δ⁴-3-Ketosteroids at pH 2 forming stable hydrazones which exhibit intense absorption specta at 300 nm. and high molar absorpitivities ranging from 14480–18750 for most steroids studied. Methyltestosterone showed exception ally high sensitivity where its molar absorpitivity was 21630. As little as 5–30 μg steroid were determined with 99.28 ± 0.65–100.16 ± 0.94% accuracy. The method was applied successfully to the micro-determination of cortisone, hydrocortisone, hydrocortisone acetate, norethisterone, norethisterone acetate, norgestrel and methyltestosterone in substance as well as in different pharmaceutical dosage forms. The precision of assay was compareble with existing spectrometric methods for ketosteroid drugs. The method is simple, accurate mean - while selective and more sensitive than the INH-method.