, Volume 40, Issue 4, pp 393–394

Simplification of the ecdysteroid radioimmunoassay by the use of protein A fromStaphylococcus aureus

  • J. T. Warren
  • W. Smith
  • L. I. Gilbert
Short Communications


Three methods of separating antibody-bound ligand from free ligand were compared for an ecdysteroid radioimmunoassay. Ecdysteroid antibody concentration and ligand specific radioactivity were adjusted to measure 2 ranges of ecdysone concentrations (0.01–2.0 ng and 0.25–32.0 ng). In comparison with the tradiotional separating agent, ammonium sulfate, neither protein A nor polyethylene glycol altered sensitivity or specificity of the radioimmunoassays. The protein A immunoglobulin precipitation method is quick and simple, making it a preferred alternative protocol for terminating ecdysteroid radioimmunoassays.


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Copyright information

© Birkhäuser Verlag 1984

Authors and Affiliations

  • J. T. Warren
    • 1
  • W. Smith
    • 1
  • L. I. Gilbert
    • 1
  1. 1.Department of BiologyUniversity of North CarolinaChapel HillUSA

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