You are not currently logged in.
Access your personal account or get JSTOR access through your library or other institution:
If You Use a Screen ReaderThis content is available through Read Online (Free) program, which relies on page scans. Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Scintillation Proximity Radioimmunoassay Utilizing 125I-Labeled Ligands
Sidney Udenfriend, Louise Diekmann Gerber, Larry Brink and Sydney Spector
Proceedings of the National Academy of Sciences of the United States of America
Vol. 82, No. 24 (Dec. 15, 1985), pp. 8672-8676
Published by: National Academy of Sciences
Stable URL: http://www.jstor.org/stable/26653
Page Count: 5
Since scans are not currently available to screen readers, please contact JSTOR User Support for access. We'll provide a PDF copy for your screen reader.
Preview not available
A unique type of radioimmunoassay is described that does not require centrifugation or separation. Microbeads containing a fluorophor are covalently linked to antibody. When an 125I-labeled antigen is added it binds to the beads and, by its proximity, the emitted short-range electrons of the 125I excite the fluorophor in the beads. The light emitted can be measured in a standard scintillation counter. Addition of unlabeled antigen from tissue extracts displaces the labeled ligand and diminishes the fluorescent signal. Application of scintillation proximity immunoassay to tissue enkephalins, serum thyroxin, and urinary morphine is described. Applications of the principle to study the kinetics of interaction between receptors and ligands are discussed.
Proceedings of the National Academy of Sciences of the United States of America © 1985 National Academy of Sciences