Capillary Electrophoresis-Based Immunoassay for Cortisol in Serum

Abstract

A competitive immunoassay for cortisol based on capillary electrophoresis (CE) and laser-induced fluorescence is described. The work involved the production of assay reagents and the development of separation conditions allowing for routine analysis of serum samples. Fluorescein-labeled cortisol was synthesized and purified. Fab fragments were produced from mouse monoclonal anticortisol antibody and purified using a POROS cation exchange chromatography column. After incubation of these reagents with serum, free and bound labeled antigen were separated by CE with high reproducibility. No prior sample cleanup of the serum samples was necessary. Serum calibration curves were established and used for the quantitation of cortisol in serum. The results demonstrate feasibility for a cortisol assay based on CE operating directly on serum samples.

Capillary Electrophoresis with Laser-induced Fluorescence Detection for Application in Intracellular Investigation of Anthracyclines and Multidrug Resistance Proteins

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Prostate Cancer in African-American Men: Serum Biomarkers for Early Detection Using Nanoparticles

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Determination of doping methyltestosterone by capillary electrophoresis immunological analysis with thermally reversible hydrogel and laser-induced fluorescence

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