[Chemiluminescence and bioluminescence in clinical analysis. Perspectives of development]

Until now, the methods of analysis by luminescence have not developed greatly in clinical biology because of the instability of the reagents and the absence of a single protocol applicable to a sufficiently wide range of assays. For this reason, the application has been limited to several assays using a specific bioluminescence reaction i.e., the ATP assay (for the measurement of bacterial contamination), and several assays which evaluate NADH production (bile acids, triglycerides, lactate). Research on assay methods that are very specific and very sensitive and do not use radioactive molecules has led to, among other things, the development of new techniques using luminescence reactions. These reactions are of two types: chemiluminescence reactions, which use molecules (luminol, dioxetane, derivatives of acridine and imidazol) that lead to an emission of light under the action of various chemical and enzymatic compounds; bioluminescence reactions produced by specific enzymatic systems (luciferases). Chemiluminescence reactions are used in several immunometric assays. The chemiluminescent marker fixed to the antigen or antibody has a low molecular weight: for this reason it does not lead to a significant modification of immunoreactivity and it is highly stable. Moreover, in certain cases it is possible to use particular properties of these markers (energy transfer, modification of the efficiency of the luminescent reaction) to carry out homogeneous immunometric assays requiring no separation step. Bioluminescence reactions have been less developed, because of the instability of enzymatic systems. However, these reactions are by far the most sensitive of all the detection techniques currently used.(ABSTRACT TRUNCATED AT 250 WORDS)