A micromethod for the quantitation by radioimmunoassay of cyclic AMP in samples containing immuno-cross reactive compounds and other interfering substances.

A procedure for measuring cyclic AMP in samples containing interfering substances, especially high concentrations of other adenine nucleotides, is described. Samples are purified by sequential chromatography on phenyl boronate followed by Dowex - 1. The final elution is with 0.1 normal hydrochloric acid; the samples are immediately ready for acetylation and radioimmunoassay. Cyclic AMP can be detected at 0.5 nanomolar without need to concentrate the sample at any step. The method has been successfully applied to samples containing 100 micromolar ATP, ADP, or AMP in tissue culture medium.