The cortisol RIA we have been using for years (Siemens DPC Coat-a-count) to measure plasma levels in non-human primates is being discontinued. Does anyone have a recommendation for another cortisol immunoassay to measure plasma levels?
Hi Patrick, I agree with Hanna and the kit by Cayman is surely one of the best (I know where was developped Antibodies and tracer with AChE which is one of the best and more reproducible and easy to use enzymatic tracer) . It is not always necessary to extract dépending of what you want to analyse (free of free+bound cortisol). For me worrking with a home made cortisol EIA for ruminant serum or plasma, I just use extraction in iced ethanol to precipitate the biggest proteins and bound cortisol to transcortine carrier, in order to assay dried and reconstituted supernatant in adapted buffer. Good luck
The labs of J.C. Wingfield and L.M. Romero have used a Cortisol (I125) RIA kit from MP Biomedical. We used it to run Degu samples collected in South America and were very happy with the performance of the assay. If I remember correctly, I think it worked out to about a dollar per tube so it is a very affordable kit. Good Luck
I recently found myself in a similar position. If you want to stick with RIA I recently used the Beckman Coulter assay (catalog IM1841) which gave comparable results to the DPC assay and is slightly cheaper.