radioimmunoassay

American  

[rey-dee-oh-im-yuh-noh-as-ey, -a-sey, -i-myoo-] / ˌreɪ di oʊˌɪm yə noʊˈæs eɪ, -æˈseɪ, -ɪˌmyu- /

noun

1. a test procedure that integrates immunologic and radiolabeling techniques to measure minute quantities of a substance, as a protein, hormone, or drug, in a given sample of body fluid or tissue.

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radioimmunoassay British  

/ ˈreɪdɪəʊˌɪmjʊnəʊˈæseɪ /

noun

1. a sensitive immunological assay, making use of antibodies and radioactive labelling, for the detection and quantification of biologically important substances, such as hormone concentrations in the blood

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radioimmunoassay Scientific  

/ rā′dē-ō-ĭm′yə-nō-ăs′ā,-ĭm-yo̅o̅′- /

1. An immunoassay in which the substance to be identified or quantified is labelled with a radioactive substance (called a tracer), such as an ion.

2. See also immunoassay tracer

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Etymology

Origin of radioimmunoassay

First recorded in 1960–65; radio- + immunoassay

Example Sentences

Many of the private testing labs hired by manufacturers seeking regulatory approval for new products are not equipped to do the radioimmunoassay analyses required to measure extremely low chemical concentrations.

From Nature

But a few drops of blood from a pinprick on the newborn’s heel can be analyzed with radioimmunoassay to identify babies at risk.

From New York Times

In their work on radioimmunoassay, Dr. Yalow and Dr. Berson used radioactive tracers to measure hormones that were otherwise difficult or impossible to detect because they occur in extremely low concentrations.

From New York Times

Scientific journals initially refused to publish their discovery of insulin antibodies, a finding fundamental to radioimmunoassay.

From New York Times

Using radioimmunoassay, she determined that people with Type 2 diabetes produced more insulin than non-diabetics, providing early evidence that an inability to use insulin caused diabetes.

From New York Times