: A mechanism for thermal production of excited states is discussed. Electron transfer from an easily oxidized donor to a suitable organic peroxide followed by oxygen-oxygen bond cleavage generates radical ion intermediates. Subsequent chemical reaction followed by charge annihilation generates electronically excitated state products. This sequence of reactions is called chemically initiated electron-exchange luminescence and is shown to be operating for diphenoyl peroxide, 1-phenylethylperoxy acetate, dimethyldioxeta-none, and 1,4-diphenyl-2,3-benzodioxin (0-xylylene peroxide). (Author)

Chemiluminescence of organic peroxides. Conversion of ground-state reactants to excited-state products by the chemically initiated electron-exchange luminescence mechanism

DNA probes and synthetic oligonucleotides in general present one of the key tools in modern molecular biology research and increasingly also in commercial applications. Along with the many applications that have been developed for and with DNA probes, faster and more sensitive detection methods are being developed. One of the most promising recent developments presents a method based on enzymatically triggered chemiluminescence. Details of this chemistry along with applications in molecular biology and immunology will be discussed and compared to conventional methods.

Applications of dioxetane chemiluminescent probes to molecular biology

Bioluminescence is a phenomenon that has fascinated mankind for centuries. Today the phenomenon and its sibling, chemiluminescence, have impacted society with a number of useful applications in fields like analytical chemistry and medicine, just to mention two. In this review, a molecular-orbital perspective is adopted to explain the chemistry behind chemiexcitation in both chemi- and bioluminescence. First, the uncatalyzed thermal dissociation of 1,2-dioxetane is presented and analyzed to explain, for example, the preference for triplet excited product states and increased yield with larger nonreactive substituents. The catalyzed fragmentation reaction and related details are then exemplified with substituted 1,2-dioxetanone species. In particular, the preference for singlet excited product states in that case is explained. The review also examines the diversity of specific solutions both in Nature and in artificial systems and the difficulties in identifying the emitting species and unraveling the color...

Chemi- and Bioluminescence of Cyclic Peroxides.

Significant advances have occurred regarding our knowledge of firefly luciferase mechanisms. Although most of this progress was an outcome of molecular biology and structural studies, important achievements have also occurred on its fundamental chemistry. Those developments are here summarized and presented in a historical perspective.

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Firefly luminescence: A historical perspective and recent developments

Methods are disclosed for determining an analyte in a medium suspected of containing the analyte. One method comprises providing (1) a medium suspected of containing the analyte, (2) a label reagent comprising a first specific binding pair (sbp) member associated with a photochemically activatable chemiluminescent compound wherein the first sbp member is capable of binding to the analyte or to a second sbp member to form a complex related to the presence of the analyte. The method further comprises photochemically activating the chemiluminescent compound. The amount of luminescence generated by the chemiluminescent compound is detected. The amount thereof is related to the amount of analyte in the medium. Compositions and kits are also disclosed.

Assay method utilizing photoactivated chemiluminescent label

Isolable dioxetans usually afford triplet rather than singlet excited products but we now show that high yields of excited singlet states are obtainable from stable dioxetans by appropriate substitution; a remarkable rate acceleration of the chemiluminescent reaction by surfaces is observed.

Singlet excited states from dioxetan decomposition

This invention concerns chemiluminescent moieties useful as labels in assays and immunoassays, and compositions and assay kits incorporating the moieties. The chemiluminescent moieties are of the type wherein attack by peroxide or molecular oxygen results in an electronically excited intermediate which decays with emission of light. The moieties are distinguished by being less prone to hydrolysis and thus exhibit greater stability.

Assays utilizing improved chemiluminescent esters, thioesters and amides

Isolation, along with expected product, of 1,2-dioxolans of rearranged skeleton from the reaction of singlet oxygen with certain hindered alkenes suggest the intermediacy of a dipolar species such as a perepoxide.

Reaction of singlet oxygen with hindered olefins: evidence for a perepoxide intermediate

Chemiluminescent moieties useful as labels in assays and immunoassays, and compositions and assay kits incorporating the moieties are described. The chemiluminescent moieties are of the type wherein attack by peroxide or molecular oxygen results in an electronically excited intermediate which decays with emission of light. The moieties are distinguished by being less prone to hydrolysis and thus exhibit greater stability.

Assays utilizing chemiluminescent esters, thioesters and amides

In accordance with the present invention, specific binding assays are disclosed which utilize an chemiluminescent compound, i.e., moiety, which has increased stability in aqueous solution. The chemiluminescent moiety is an ester, thioester or amide in which the ester, thioester or amide linkage is between (1) a heterocyclic ring or ring system containing a carbon atom to which the linkage is attached, wherein the heteroatom within the heterocyclic ring or ring system is in an oxidation state which renders such carbon atom susceptible to attack by peroxide or molecular oxygen to form an intermediate which decays to produce chemiluminescence, and (2) an aryl ring or ring system. The aryl ring or ring system contains at least one substituted six-member ring. The substituted six-member ring has two or more substituent groups, where at least two of said two or more substituent groups sterically hinder hydrolysis of said linkage. One or more of the substituent groups which sterically hinder hydrolysis of said linkage may be an electron withdrawing group. The substituted six-member ring may have one or more additional substituent groups in addition to the substituent groups which sterically hinder hydrolysis of the linkage. Such additional substituent groups may also be an electron withdrawing group. The carbon atom in the heterocyclic ring or ring system, to which the linkage is attached, may also have a secondary substituent of the formula RnX-, where X is selected from the group consisting of O, N, S and C, where R is any group, and where n is a number such that X has proper valency. Other chemiluminescent moieties are disclosed which are characterized by a heterocyclic ring or ring system and a secondary substituent of the formula RnX-, with the ester, thioester or amide linkage being between the heterocyclic ring or ring system and a leaving group. The disclosed chemiluminescent moieties can also include substituents at peri positions within the heterocyclic ring or ring system. Also in accordance with the present invention, compositions including and assay kits incorporating such chemiluminescent moieties are disclosed.

Iraj Beheshti

Papers

Singlet excited states from dioxetan decomposition

Assays utilizing improved chemiluminescent esters, thioesters and amides

Reaction of singlet oxygen with hindered olefins: evidence for a perepoxide intermediate

Assays utilizing chemiluminescent esters, thioesters and amides

New chemiluminescent esters, thioesters and amides used in immunoassays