Definition of radioimmunoassay in English:
 radioimmunoassay
noun ˌreɪdɪəʊɪˌmjʊnəʊaˈseɪˌrādēōˌimyənōˈasā
Medicine A technique for determining antibody levels by introducing an antigen labelled with a radioisotope and measuring the subsequent radioactivity of the antibody component.
 Example sentencesExamples
-  To confirm the diagnosis, allergen specific serum IgE was measured by radioimmunoassay according to the manufacturer's instructions.
 -  Basal serum C peptide levels were measured by radioimmunoassay after an overnight fast.
 -  Plasma folate levels were measured by radioimmunoassay for the quantitative determination of vitamin B 12 and folate in serum.
 -  Routine determination in blood now involves the technique of radioimmunoassay - even very low concentrations of hormone can be determined quite rapidly on a large number of samples.
 -  As an objective indicator of the infants' exposure to passive smoke, serum cotinine was measured by radioimmunoassay, with the lower level of detection at 0.1 [micro] g/ml.