A5032268643- bioluminescence and chemiluminescence research
- Radical Photochemical Reactions
- Advanced Chemical Sensor Technologies
- Advanced biosensing and bioanalysis techniques
- Insect and Pesticide Research
- Free Radicals and Antioxidants
- Biocrusts and Microbial Ecology
- Analytical Chemistry and Chromatography
- Antioxidant Activity and Oxidative Stress
- Click Chemistry and Applications
- Electrochemical sensors and biosensors
- Photochemistry and Electron Transfer Studies
- Biosensors and Analytical Detection
- Luminescence and Fluorescent Materials
- Chemical Reactions and Isotopes
- Nicotinic Acetylcholine Receptors Study
- Bee Products Chemical Analysis
- Molecular Sensors and Ion Detection
- Innovative Microfluidic and Catalytic Techniques Innovation
- Porphyrin and Phthalocyanine Chemistry
- Photoreceptor and optogenetics research
- Botanical Research and Applications
- Molecular Junctions and Nanostructures
Universidade de São Paulo
2010-2022
Yale University
2022
Almost fifty years after the discovery of peroxyoxalate reaction by E. A. Chandross in early nineteen sixties, this review article intends to give a general overview on mechanistic aspects system and describe principles its analytical application.After short introduction chemiluminescence history discovery, high-energy intermediate formation, structure with an activator are discussed.Finally, applications exemplified using representative recent examples, including oxalic acid detection...
The chemiluminescence of cyclic peroxides activated by oxidizable fluorescent dyes is an example chemically initiated electron exchange luminescence (CIEEL), which has been used also to explain the efficient bioluminescence fireflies. Diphenoyl peroxide and dimethyl-1,2-dioxetanone were as model compounds for development this CIEEL mechanism. However, chemiexcitation efficiency diphenoyl was found be much lower than originally described. In work, we redetermine quantum...
The chemiluminescent decomposition of 1,2-dioxetanones (α-peroxylactones), catalyzed by an appropriate fluorescent activator, is important simple model for efficient bioluminescent transformations. In this work, we report experimental data on the two spiro-substituted 1,2-dioxetanone derivatives, which support occurrence intermolecular electron transfer from activator to peroxide. low efficiency studied systems associated with steric hindrance during chemiexcitation sequence, rationalized...
Almost all chemiluminescent and bioluminescent reactions involve cyclic peroxides. The structure of the peroxide reaction conditions determine quantum efficiency light emission. Oxidizable fluorophores, so-called activators, react with 1,2-dioxetanones promoting former to their first singlet excited state. This transformation is inefficient does not occur 1,2-dioxetanes; however, they have been used as models for efficient firefly bioluminescence. In this work, we use SA-CASSCF/CASPT2 method...
UV-like DNA damage is created in the dark by chemiexcitation, which UV-activated enzymes generate reactive oxygen and nitrogen species that create a dioxetane on melanin. Thermal cleavage creates an electronically excited triplet-state carbonyl whose high energy transfers to DNA. Screening natural compounds for ability quench this identified polyenes, polyphenols, mycosporine-like amino acids, related better known as antioxidants. To eliminate false positives such ROS RNS scavengers, we then...
A RARE REACTION PRODUCT.The production of visible light by chemical reactions constitutes interesting and fascinating phenomena several reaction mechanisms are discussed to rationalize excited state formation.Most efficient chemiluminescence thought involve one or more electron transfer steps chemiexcitation is believed occur radical annihilation.A brief introduction the general principles main known will be given here.Subsequently, recent results on mechanistic elucidation systems, as...
Cyclic four-membered ring peroxides are important high-energy intermediates in a variety of chemi and bioluminescence transformations. Specifically, α-peroxylactones (1,2-dioxetanones) have been considered as model systems for efficient firefly bioluminescence. However, the preparation such highly unstable compounds is extremely difficult and, therefore, only few research groups able to study properties these substances. In this study, synthesis, purification characterization three...
Abstract Betalains are phytochemicals of nutraceutical importance that emerged as potent antioxidants, preventing radical chain propagation and the deleterious health effects oxidative stress. However, despite wide application betalains color additives in products for human consumption, little is known about relationship between their structure antioxidant potential. Here we investigate mechanism action three regioisomeric phenolic show meta isomer has higher antiradical capacity than most...
Intermolecular chemically initiated electron exchange luminescence (CIEEL) systems are known to possess low chemiluminescence efficiency; whereas, the corresponding intramolecular transformations highly efficient. As reasons for this discrepancy not known, we report in work our studies of solvent-cavity effect on efficiency two intermolecular CIEEL systems, catalyzed decomposition diphenoyl peroxide and a relatively stable 1,2-dioxetanone derivative, spiro-adamantyl-1,2-dioxetanone. The...
Abstract The peroxyoxalate reaction is one of the most efficient chemiluminescence transformations, with emission quantum yields up to 50%; additionally, it widely utilized in analytical and bioanalytical assays. Although real reason for its extremely high efficiency still not yet understood, mechanism this transformation has been well elucidated anhydrous medium. Contrarily, only few mechanistic studies have performed aqueous media, which would be great importance application biological...
Chemiluminescence properties of the peroxyoxalate reaction in presence activators bearing electron withdrawing substituents were studied, to evaluate possible occurrence an inverse transfer, from peroxide intermediate activator, its chemiexcitation step. Relative catalytic rate constants and singlet quantum yields obtained for reaction, using 9-chloro, 9,10-dichloro, 9-cyano 9,10-dicyanoanthracenes as activators. The linear free-energy correlation relative with activators' reduction...