Chemiluminescent reaction of lucigenin with reducing sugars.
The chemiluminescent reaction, in alkaline solution, of lucigenin with the reducing sugars sorbose, fructose, lactose, glucose, xylose, galactose, arabinose and mannose has been studied. There is a linear relationship (correlation coefficient = 0.996) between the emission intensity and the second-order rate constant for the alkaline oxidation of these sugars. The emission intensity is linearly related to the sugar concentration; at high sugar concentrations (5mM) it is independent of the lucigenin concentration, but at low concentrations (<0.05mM) is linearly related to the lucigenin concentration. These facts support the view that the rate-limiting step is the tautomerization of the sugars to the 1,2-enediol form; the enediol then undergoes reaction with lucigenin.
Lucigenin chemilumiscence and biomolecules
Heparin, a polymer of glucosamien and uronic acids, is subjected to acid hydrolysis to be degraded to disaccharides which are in turn quantified by using a chemilumiscent reaction with lucigenin. The hydrolysis time used was 4 h in 0.25–0.5 M sulfuric acid at 90°C, and the optimum reagent concentrations for the chemiluminescent reaction were 1 mM lucigenin and 0.5 M KOH. The detection limit is 90 μg of heparin and the response is linear up to 10 mg of heparin. The relative standard deviation for the method is 10% with a 4-h hydrolysis and 4% with an 8-h hydrolysis; the relative standard deviation for the measurement step is 2%.
Applications of bio- and chemiluminescence in the clinical laboratory.
Many papers have been published in recent years describing the analytical uses of bio- and chemiluminescent reactions (for reviews see 1-10). Although several of these methods, which are often very sensitive and specific, can be applied in clinical laboratories, they are still little known and have in general not been used for routine assays. We propose to survey existing methods and to discuss their applicability. Extensive information on the mechanisms of bio- and chemiluininescence can be found in several recent reviews (11-19) and books and will not be dealt with in the present article.