'Central to the study of free radical processes is the ability to identify and localize their cellular site of formation. Under the best of experimental conditions, spin trapping/ESR spectroscopy can only characterize intracellular production of specific free radicals and confocal microscopy can only localize the site of their formation. In ... More
Trace determination of hydroxyl radical in biological systems.
AuthorsLi B, Gutierrez PL, Blough NV
JournalAnal Chem
PubMed ID9360488
A simple and highly sensitive method to quantify the rates of production of OH in biological systems is described. This method employs the reaction between OH and dimethyl sulfoxide to generate quantitatively a methyl radical, which then reacts with a fluorescamine-derivatized nitroxide to produce the stable O-methylhydroxylamine. This O-methylhydroxylamine is ... More
Combined liquid chromatography/mass spectrometry of the radical adducts of a fluorescamine-derivatized nitroxide.
AuthorsJohnson CG, Caron S, Blough NV
JournalAnal Chem
PubMed ID8779444
Dynamic liquid secondary ion mass spectrometry (dyn-LSIMS) was employed to acquire continuous, on-line mass spectral data from the effluent of a reversed-phase high-performance liquid chromatograph (HPLC) used to separate a broad suite of carbon-centered radicals trapped as the O-alkylhydroxylamine adducts of an amino nitroxide that was subsequently derivatized with fluorescamine. ... More
Comparison of fluorescence-based techniques for the quantification of particle-induced hydroxyl radicals.
AuthorsCohn CA, Simon SR, Schoonen MA,
JournalPart Fibre Toxicol
PubMed ID18307787
ABSTRACT: BACKGROUND: Reactive oxygen species including hydroxyl radicals can cause oxidative stress and mutations. Inhaled particulate matter can trigger formation of hydroxyl radicals, which have been implicated as one of the causes of particulate-induced lung disease. The extreme reactivity of hydroxyl radicals presents challenges to their detection and quantification. Here, ... More
A fluorophore-containing nitroxide as a probe to detect superoxide and hydroxyl radical generated by stimulated neutrophils.
AuthorsPou S, Huang YI, Bhan A, Bhadti VS, Hosmane RS, Wu SY, Cao GL, Rosen GM
JournalAnal Biochem
PubMed ID8396365
Toward the development of a fluorescence assay in combination with confocal microscopy to image free radicals generated by cells, we synthesized a fluorophore-nitroxide, 5-((2-carboxy)phenyl)-5-hydroxy-1-((2,2,5,5-tetramethyl-1-oxypyrrolid in-3- yl)methyl)-3-phenyl-2-pyrrolin-4-one sodium salt, and tested the applicability of this probe to detect oxygen-centered free radicals. The reaction of the fluorophore-nitroxide with superoxide (10 microM/min) generated ... More
Light induces peroxidation in retina by activating prostaglandin G/H synthase.
AuthorsHanna N, Peri KG, Abran D, Hardy P, Doke A, Lachapelle P, Roy MS, Orquin J, Varma DR, Chemtob S
JournalFree Radic Biol Med
PubMed ID9378368
Prostaglandin G/H synthase (PGHS) has been shown to generate peroxides to a significant extent in the retina and absorbs light at the lower end of the visible spectrum. We postulated that PGHS could be an important initial source of peroxidation in the retina exposed to light, which would in turn ... More