Competitive chemiluminescent assay for cyclic nucleotide monophosphates

A kit for conducting a competitive, cell-based immunoassay for the concentration of a cyclic nucleotide phosphate, said kit comprising:

• a conjugate of said cyclic nucleotide phosphate and an alkaline phosphatase;
• an antibody which binds said cyclic nucleotide phosphate;
• and
• an alkaline phosphatase-triggered 1,2-dioxetane which decomposes in the presence of alkaline phosphatase to release light.

A competitive assay for determining the concentration of a cyclic nucleotide phosphate in a sample comprising cells, the assay comprising:

• lysing cells in the sample;
• combining, in a reaction chamber provided with a capture antibody, (1) a conjugate of said cyclic nucleotide phosphate and an alkaline phosphatase, (2) a primary antibody that is bound by said capture antibody and that binds, when so bound, said cyclic nucleotide phosphate, and (3) said sample to form a reaction mixture,
• incubating the reaction mixture so as to permit said cyclic nucleotide phosphate and said conjugate to bind competitively with said primary antibody,
• washing said reaction mixture to remove any unbound conjugate or antibody,
• adding to said reaction mixture an alkaline phosphatase-triggered 1,2-dioxetane which, when contacted with alkaline phosphatase in said conjugate, is caused to decompose and release light, and
• detecting any chemiluminescent signal emitted by said reaction mixture,
• wherein said signal is indicative of the concentration of cyclic nucleotide phosphate in the sample.