Please use this identifier to cite or link to this item: https://hdl.handle.net/1959.11/52878
Title: Formation and Properties of Peroxynitrite as Studied by Laser Flash Photolysis, High-Pressure Stopped-Flow Technique, and Pulse Radiolysis
Contributor(s): Kissner, Reinhard (author); Nauser, Thomas (author); Bugnon, Pascal (author); Lye, Peter G  (author)orcid ; Koppenol, Willem H (author)
Publication Date: 1997-11-01
DOI: 10.1021/tx970160x
Handle Link: https://hdl.handle.net/1959.11/52878
Abstract: Flash photolysis of alkaline peroxynitrite solutions results in the formation of nitrogen monoxide and superoxide. From the rate of recombination it is concluded that the rate constant of the reaction of nitrogen monoxide with superoxide is (l.9 ± 0.2) × 1010 M-1 s-1. The pKa of hydrogen oxoperoxonitrate is dependent on the medium. With the stopped-flow technique a value of 6.5 is found at millimolar phosphate concentrations, while at 0.5 M phosphate the value is 7.5. The kinetics of decay do not follow first-order kinetics when the pH is larger than the pKa, combined with a total peroxynitrite and peroxynitrous acid concentration that exceeds 0.1 mM. An adduct between ONOO- and ONOOH is formed with a stability constant of (1.0 ± 0.l) × 104 M. The kinetics of the decay of hydrogen oxoperoxonitrate are not very pressure-dependent: from stopped-flow experiments up to 152 MPa, an activation volume of 1.7 ± 1.0 cm3 mol-1 was calculated. This small value is not compatible with homolysis of the O-O bond to yield free nitrogen dioxide and the hydroxyl radical. Pulse radiolysis of alkaline peroxynitrite solutions indicates that the hydroxyl radical reacts with ONOO- to form [(HO)ONOO]•- with a rate constant of 5.8 × l09 M-1 s-1. This radical absorbs with a maximum at 420 nm (ε = 1.8 × 103 M-1 cm-1) and decays by second-order kinetics, k = 3.4 × l06 M-1 s-1. Improvements to the biomimetic synthesis of peroxynitrite with solid potassium superoxide and gaseous nitrogen monoxide result in higher peroxynitrite to nitrite yields than in most other syntheses.
Publication Type: Journal Article
Source of Publication: Chemical Research in Toxicology, 10(11), p. 1285-1292
Publisher: American Chemical Society
Place of Publication: United States of America
ISSN: 1520-5010
0893-228X
Fields of Research (FoR) 2020: 340401 Biologically active molecules
340607 Reaction kinetics and dynamics
340502 Natural products and bioactive compounds
Socio-Economic Objective (SEO) 2020: 280105 Expanding knowledge in the chemical sciences
240801 Human biological preventatives
Peer Reviewed: Yes
HERDC Category Description: C1 Refereed Article in a Scholarly Journal
Appears in Collections:Journal Article
School of Science and Technology

Files in This Item:
1 files
File SizeFormat 
Show full item record

SCOPUSTM   
Citations

593
checked on Jan 4, 2025

Page view(s)

562
checked on Mar 8, 2023

Download(s)

2
checked on Mar 8, 2023
Google Media

Google ScholarTM

Check

Altmetric


Items in Research UNE are protected by copyright, with all rights reserved, unless otherwise indicated.