Generation of high-energy chemiluminophores in ambient light

YuB TSAPLEV, RF VASIL EV, AV TROFIMOV Emanuel Institute of Biochemical Physics, Russian Academy of Sciences, ul. Kosygina 4, Moscow 119334, Russian Federation E-mail tsap 04 mail.ru, rfv28 mail.ru, avt 2003 mail.ru 

The chemuluminescence measurements were performed with a photon-counting 

The interaction of both Rg and Rg isomers with bases is exothermic however, the energy released in the reaction of Rg with HO is not sufficient for the electronic excitation of the hydrazone anion, the chemiluminescence emitter. The PM3 computations reveal that the enthalpy of the Rg formation exceeds that of the Rg species by 130 kJ/mol, which covers the energy deficiency for the excitation of the light emitter. Thus, the Rg species constitutes the putative high-energy chemiluminophore, which is readily generated in the ambient light. 

Intermediate photodimeric species. The following example par excellence for the LCCL manifestation is provided by the base-initiated chemiluminescence of preirradiated 9-anthrone.2 Addition of bases to the 9-anthrone solutions stored in the dark does not trigger a chemiluminescence process. However, exposure of the reactant to ambient light and subsequent addition of base results in excited-state generation as manifested by the chemiluminescence emission. The products of the 9-anthrone photolysis in dioxane were separated by high-performance thin-layer chromatography. 

At a first glance, the ability of ambient laboratory light to create chemiluminescence seems astonishing. However, under ordinary illumination (only a few mW/m2), more than 1013 photons pass through an area of 1 cm2 per second, which is 109 times greater than the detection limit of laboratory chemiluminometers. Clearly, this gap can be filled by numerous chemical systems, for which the absorption efficiencies multiplied by the photochemical transformation and the chemiluminescence yields are no less than 10 9. This implies that the list of known chemiluminescent reactions needs to be revisited to disclose the systems, which may be particularly influenced by the ambient illumination while preparing the reaction mixtures. 

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GENERATION OF HIGH-ENERGY CHEMILUMINOPHORES IN AMBIENT LIGHT... 

Generation of High-Energy Chemiluminophores in Ambient Light 149... 

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