Additional experimental evidence is presented for in vitro generation of hydroxyl radicals because of redox cycling of environmentally persistent free radicals (EPFRs) produced after adsorption of 2-monochlorophenol at 230 °C (2-MCP-230) on copper oxide supported by silica, 5% Cu(II)O/silica (3.9% Cu). A chemical spin trapping agent, 5,5-dimethyl-1-pyrroline-N-oxide (DMPO), in conjunction with ...

Free radicals may be reaction intermediates in biological systems in more situations than are presently recognized. However, progress in detecting such species by Electron Spin Resonance (ESR) has been relatively slow. ESR is a very sensitive technique for free radical detection and characterization. It can be used to investigate very low concentrations of radicals provided that they are stable...

Using the spin trap, 5,5-dimethyl-1-pyrroline-1-oxide (DMPO) and an excess of dimethyl sulfoxide, we previously reported that in the absence of an exogenous iron catalyst, human neutrophils will not generate hydroxyl radical, manifested as the catalse-inhibitable methyl radical spin-trapped adduct, 2,2,5-trimethyl-1-pyrrolidinyloxy (DMPO-CH3) (Britigan, B. E., Rosen, G. M., Chai, Y., and Cohen,...

1. General information S2 2. Synthesis of carboxylic acids S3 3. Stoichiometric experiments with benzoyl hypobromite II S4 4. Optimization and control reactions S8 5. Oxidant screen S9 6. General procedure for the visible light-promoted aryl decarboxylation S9 7. Scope of the visible light-promoted decarboxylation/radical trapping S10 8. Mechanistic studies S19 a) Stern-Volmer luminescence quen...

ESR spin-trapping method has been used for the study of radiation-induced radicals in· powdered dihydrothymine. Four approximately equal small proton couplings (AH' = 0.35 mT), a larger proton coupling (AH = 0.195 mT) and a nitrogen coupling (AN = = 0.295 mT) are attributed to the nitroxide radical formed by reaction of the spin trap with 6-dihydrothymyl radical upon dissolving of dihydrothymin...

Introduction Nitric oxide (NO) was first appreciated as a biological mediator in its role as endothelial derived relaxing factor, which is responsible for regulation of blood vessel relaxation and its maintenance [ 11. It also became evident that NO was produced in the brain, catalyzed by a nitric oxide synthase (NOS), where NO acts as a synaptic neuronal messenger [2]. NO is a gaseous and high...

ion and subsequent deprotonation gives rise to phenoxy radicals, which play a pivotal role in lignin chemistry. Overall spin trapping systems could be powerful tools to understand the radical intermediates involved in lignin chemistry. In Table 4 our data on spin trap experiments with DIPPMPO and different phenols are shown. There are different oxidation systems for the generation of phenoxy ra...

The relationship between physical activity, physical fitness and total radical trapping antioxidant potential (TRAP) was examined in the Northern Ireland Health and Activity Survey. This was a cross-sectional population study (n = 1600) using a two-stage probability sample of the population. TRAP was calculated using the sum of the individual serum antioxidant concentrations (urate, protein thi...

Atom transfer radical addition of bromonitromethane and 1,2-dibromotetrafluoroethane to alkenes is described. The reaction performed under blue light irradiation using two catalysts: 4CzIPN manganese (II) bromide. cyanoarene photocatalyst serves for the redox activation starting organic bromide, while salt facilitates trapping alkyl with formation carbon–bromine bond.

Electron spin resonance spectroscopy has been used to study free radical generation in rats with acute sodium formate poisoning. The in vivo spin-trapping technique was used with alpha-(4-pyridyl-1-oxide)-N-t-butylnitrone (POBN), which reacts with free radical metabolites to form radical adducts, which were detected in the bile and urine samples from Fischer rats. The use of [(13)C]-sodium form...