Solution-phase immunoassay for determination of cortisol in serum by capillary electrophoresis.
We describe a competitive solution-phase immunoassay for serum cortisol determination that involves capillary electrophoresis (CE) combined with laser-induced fluorescence for separation and quantification. A polyclonal antibody preparation and fluorescein-labeled cortisol are used as assay reagents. 8-Anilino-1-naphthalenesulfonic acid was added to the serum sample during the assay to promote the release of cortisol from endogenous binding proteins. Conditions for the rapid separation of free and bound labeled antigen by CE were developed. Aspects of assay performance are evaluated in this report. The resulting assay protocol allows for the analysis of serum samples without extraction or other sample preparation steps.
Schmalzing
D
D
PerSeptive Biosystems, Framingham, MA 01701, USA.
Nashabeh
W
W
Fuchs
M
M
D000817:Anilino Naphthalenesulfonates; D000911:Antibodies, Monoclonal; D002197:Capillary Action; D004586:Electrophoresis / Q000379:methods* / Q000706:statistics & numerical data; D019793:Fluorescein; D005452:Fluoresceins; D005456:Fluorescent Dyes; D006801:Humans; D006854:Hydrocortisone / Q000097:blood*; D007118:Immunoassay / Q000379:methods* / Q000706:statistics & numerical data; D007140:Immunoglobulin Fab Fragments; D007202:Indicators and Reagents; D011485:Protein Binding; D012680:Sensitivity and Specificity
D000817:Anilino Naphthalenesulfonates; D000911:Antibodies, Monoclonal; D005452:Fluoresceins; D005456:Fluorescent Dyes; D007140:Immunoglobulin Fab Fragments; D007202:Indicators and Reagents; C027132:1-anilino-8-naphthalenesulfonate; D019793:Fluorescein; D006854:Hydrocortisone