Improved indirect and direct radioimmunoassay for carcinoembryonic antigen. [/sup 125/I tracer technique]

Conference · Tue Feb 01 00:00:00 EST 1977 · Clin. Chem.; (United States)

OSTI ID:6289728

Kumar, M S; Carl, K J; Deodhar, S D

Values obtained by the indirect and the direct assays for carcinoembryonic antigen by use of the CEA Roche method and reagents differ significantly. In 32 samples the latter method gave values almost twofold those obtained by the former. The mean ratio for direct/indirect was 1.9 +- 0.6. Analytical recovery experiments on samples to which known amounts of the antigen had been added showed a similar disparity. A simple modification of these two procedures, involving addition of normal human plasma (containing less than 2.0 ..mu..g of the antigen per liter) to standards, eliminated this discrepancy. In the indirect method, standards were added to normal human plasma, then extracted with perchloric acid before assay. In the direct assay normal human plasma instead of goat serum, was added to standards. With these modifications the analytical recoveries of added CEA by the indirect and direct methods were 87 +- 17% and 99.7 +- 8%, respectively, and the mean ratio between two methods was 1.2 +- 0.4.

• Research Organization: Cleveland Clinic Foundation, OH
• OSTI ID: 6289728
• Journal Information: Clin. Chem.; (United States), Vol. 25:2; Conference: 29. national meeting of the AACC, Chicago, IL, USA, Jul 1977
• Country of Publication: United States
• Language: English

Related Subjects

62 RADIOLOGY AND NUCLEAR MEDICINE
ANTIGENS
RADIOIMMUNOASSAY
BLOOD PLASMA
EXPERIMENTAL DATA
GRAPHS
IODINE 125
ISOLATED VALUES
STANDARDS
STATISTICS
TRACER TECHNIQUES
BETA DECAY RADIOISOTOPES
BIOLOGICAL MATERIALS
BLOOD
BODY FLUIDS
DATA
DATA FORMS
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
INFORMATION
INTERMEDIATE MASS NUCLEI
IODINE ISOTOPES
ISOTOPE APPLICATIONS
ISOTOPES
MATHEMATICS
NUCLEI
NUMERICAL DATA
ODD-EVEN NUCLEI
RADIOASSAY
RADIOISOTOPES
550601* - Medicine- Unsealed Radionuclides in Diagnostics