From the firefly bioluminescence to the dioxetane-based (AMPPD) chemiluminescence immunoassay: a retroanalysis

Abstract

Chemiluminescent dioxetanes, which are enzymically triggerable, have proved to be a valuable tool in diagnostic clinical applications. In this context, the phenomenon of firefly bioluminescence (the most efficient light-producing system so far) has served as an excellent example to develop new chemiluminescent probes for bioanalysis, in particular chemiluminescence immunoassays. From the recognition of the molecular details of the firefly bioluminescence, a chemical equivalent has been conceived which possesses the essential features for efficient generation of light, i.e., thermal persistence through spiroadamantyl substitution, spontaneous chemically initiated electron exchange luminescence (CIEEL)-active decomposition after enzymic triggering, efficient light emission as a lasting glow and convenient synthesis by photooxygenation. This has led to a rationally designed dioxetane, namely the 3-(2′-spiroadamantyl)-4-methoxy-4-(3″-phosphoryloxy)-phenyl-1,2-dioxetane (AMPPD) derivative, which serves as a substrate for alkaline phosphatase and, in terms of sensitivity, has surpassed the hazardous radioactive immunoassay probes. This paper gives a historical account in the form of a retroanalysis of the success story behind the rational design of the first enzymically triggerable, CIEEL-active AMPPD chemiluminescent probe.