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competitive binding assay

[kəm-pĕt′ĭ-tĭv]
n.
  1. An assay in which a biologically specific binding agent competes for radioactively labeled or unlabeled compounds, used especially to measure the concentration of hormone receptors in a sample by introducing a radioactively labeled hormone.
The American Heritage® Stedman's Medical Dictionary Copyright © 2002, 2001, 1995 by Houghton Mifflin Company. Published by Houghton Mifflin Company.