Literature DB >> 1313843

Optimal EPR detection of weak nitroxide spin adduct and ascorbyl free radical signals.

G R Buettner1, K P Kiminyo.   

Abstract

We have investigated the optimal nominal power settings for the electron paramagnetic resonance detection of typical nitroxides, nitroxide spin adducts, and the ascorbyl free radical. In room temperature aqueous solution, we find that, for all the nitroxides examined, saturation effects begin at approx. 25 mW nominal power with maximum signal intensity achieved at approx. 100 mW power when using a TM110 cavity. For the ascorbyl free radical, we find that saturation effects begin at approx. 16 mW nominal power and that maximum peak-to-peak signal amplitude is obtained at approx. 40 mW microwave power. For the ascorbyl free radical, we find that a modulation amplitude of approx. 0.65 G yields the maximum signal height for the doublet signal. This information will help researchers maximize the EPR signal height of minimally detectable free radicals such as encountered in biological systems.

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Year:  1992        PMID: 1313843     DOI: 10.1016/0165-022x(92)90054-e

Source DB:  PubMed          Journal:  J Biochem Biophys Methods        ISSN: 0165-022X


  11 in total

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Journal:  J Physiol       Date:  2010-09-27       Impact factor: 5.182

4.  Ascorbate removes key precursors to oxidative damage by cell-free haemoglobin in vitro and in vivo.

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5.  Pharmacological ascorbate with gemcitabine for the control of metastatic and node-positive pancreatic cancer (PACMAN): results from a phase I clinical trial.

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6.  The nitric oxide donor S-nitroso-N-acetylpenicillamine (SNAP) increases free radical generation and degrades left ventricular function after myocardial ischemia-reperfusion.

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7.  The syringe nitroxide free radical--Part II.

Authors:  G R Buettner; M K Sharma
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8.  Manganoporphyrins increase ascorbate-induced cytotoxicity by enhancing H2O2 generation.

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10.  Dynamic nuclear polarization-magnetic resonance imaging at low ESR irradiation frequency for ascorbyl free radicals.

Authors:  Shinji Ito; Fuminori Hyodo
Journal:  Sci Rep       Date:  2016-02-19       Impact factor: 4.379

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