D. Schmalzing et al., SOLUTION-PHASE IMMUNOASSAY FOR DETERMINATION OF CORTISOL IN SERUM BY CAPILLARY ELECTROPHORESIS, Clinical chemistry, 41(9), 1995, pp. 1403-1406
We describe a competitive solution-phase immunoassay for serum cortiso
l determination that involves capillary electrophoresis (CE) combined
with laser-induced fluorescence for separation and quantification. A p
olyclonal antibody preparation and fluorescein-labeled cortisol are us
ed as assay reagents. 8-Anilino-1-naphthalenesulfonic acid was added t
o the serum sample during the assay to promote the release of cortisol
from endogeneous binding proteins. Conditions for the rapid separatio
n of free and bound labeled antigen by CE were developed. Aspects of a
ssay performance are evaluated in this report. The resulting assay pro
tocol allows for the analysis of serum samples without extraction or o
ther sample preparation steps.