REEVALUATION OF THE SPECTRAL AND KINETIC PROPERTIES OF HO2 AND O2‐ FREE RADICALS

@article{Bielski1978REEVALUATIONOT,
  title={REEVALUATION OF THE SPECTRAL AND KINETIC PROPERTIES OF HO2 AND O2‐ FREE RADICALS},
  author={Benon H. J. Bielski},
  journal={Photochemistry and Photobiology},
  year={1978},
  volume={28}
}
  • B. Bielski
  • Published 1 October 1978
  • Chemistry
  • Photochemistry and Photobiology
Abstract— The spectra and molar absorbances of the HO2 and O2‐ free radicals have been redetermined in aqueous formate solutions by pulse and stopped‐flow radiolysis as well as by 60Co gamma‐ray studies. The extinction coefficients at the corresponding maxima and 23°C are 225= 1400 ± 80 M‐1 cm‐1 and 225= 2350 ± 120 M‐1 cm‐1 respectively. Reevaluation of earlier published rate data in terms of the new extinction coefficients yielded the following rate constants for the spontaneous decay of HO2… Expand
Reactivity of superoxide anion towards CoII and CoIIIedta complexes
The reactions of O2- with CoIIedta= and CoIIIedta- have been investigated at pH 9 using the pulse-radiolysis technique. From spectrophotometric observations in the UV, it is concluded that theExpand
Kinetic and spectral properties of rhodamine 6G free radicals: a pulse radiolysis study
Abstract Using the pulse radiolysis technique Br 2 − has been shown to react with the laser dye, rhodamine 6G (RhH + ) to produce cation radicals. At pH 4, the species designated RhH 2 + is producedExpand
Studies of the reactivity of trolox with Mn3+/Fe3+ complexes by pulse radiolysis.
TLDR
The rates and mechanisms for the reactions between Trolox, a synthetic analogue of alpha-tocopherol, Br2- and Mn3+-phosphate were determined under aerobic and anaerobic conditions by fast kinetic methods and are discussed in light of the known antioxidant properties of vitamin E. Expand
Oxidation of glyoxal initiated by OH in oxygenated aqueous solution
The kinetics and mechanism of the oxidation of glyoxal, which is a constituent of cloud water, initiated by OH in oxygenated solution have been investigated using pulse radiolysis with opticalExpand
Revisited water radiolysis at elevated pH by accounting O3˙− kinetics at low and high LET
Ozonide radical, O3˙−, is used in this study for probing radiolytic species formed in the radiolysis of liquid water at elevated pH. Its formation allows the scavenging of O˙− whereas itsExpand
Photooxidation of Pterin in Aqueous Solutions: Biological and Biomedical Implications
TLDR
Pterin is not light‐sensitive in the absence of molecular oxygen, but it undergoes photooxidation in the presence of O2, yielding several nonpteridinic products, and its importance from a biomedical point of view is discussed. Expand
Kinetics and spectroscopy of the SO4− radical in aqueous solution
Abstract Laser flash photolysis of S2O82− at 248 nm and 266 nm has been employed in conjunction with time-resolved long path absorption detection to investigate the kinetics and spectroscopy of theExpand
Mechanistic insight into superoxide radical-mediated degradation of carbon tetrachloride in aqueous solution: An in situ spectroscopic and computational study
Abstract Contemporary studies emphasize that superoxide radical ( O 2 ∙ - ) exhibits the potential to degrade organic contaminants, but practical application of this radical in engineered watersExpand
Antioxidant properties of phenols
  • M. Foti
  • Medicine, Chemistry
  • The Journal of pharmacy and pharmacology
  • 2007
The current understanding of the antioxidant properties of phenols (in homogeneous solutions) is reviewed, with particular emphasis on the role of the solvent. Phenols (ArOH) are known to reduce theExpand
Photolysis of d-fructose in aqueous solution
Abstract In the 254-nm photolysis of aqueous solutions of d -fructose, only the openchain form, which is present to an extent of ∼0.8% in equilibrium with the cyclic forms, absorbs the light. A studyExpand
...
1
2
3
4
5
...

References

SHOWING 1-10 OF 13 REFERENCES
Electrochemical generation and reactivity of the superoxide ion in aqueous solutions
Abstract By making use of the previously observed fact that oxygen is reduced, in aqueous solutions at surfactant-covered mercury electrodes, to the superoxide stage only, the redox system O2/O2− asExpand
Study of the superoxide radical chemistry by stopped-flow radiolysis and radiation induced oxygen consumption. [Electron beams]
The chemical reactivity of the superoxide radical has been studied at pH 10 and 23/sup 0/C by absorption spectroscopy in a fast kinetics spectrophotometer and by radiation induced oxygen consumptionExpand
Mechanism of the disproportionation of superoxide radicals
New measurements are reported on the rate of the spontaneous uncatalyzed second-order decay of the superoxide radical in aqueous solution at 23/sup 0/C. By extreme purification of reagents, andExpand
The radiolotic yield of reducing radicals in neutral aqueous solution
Abstract By use of the ultrasensitive Cary Model 16 spectrophotometer, accurate initial γ-ray yield values were obtained at doses of only 30–150 rad for the oxidation of ferrous sulfate in air-Expand
RADIATION CHEMISTRY OF OXYGENATED AQUEOUS SOLUTIONS.
The activity in radiation chemistry in recent years has been so extensive that it seems impossible to review the whole field. This review will cover only problems in the radiation chemistry ofExpand
Stopped flow spectrophotometric observation of superoxide dismutation in aqueous solution
TLDR
Results are presented on the second-order dismutation of superoxide in the pH 7-11 range, the kinetic behavior of bovine superoxide dismutase in this pH region, and the decay of O~ in the presence of H202 which show that the Haber-Weiss reaction is inhibited. Expand
...
1
2
...