scholarly journals Intrinsic Buffer Hydroxyl Radical Dosimetry Using Tris(Hydroxymethyl)Aminomethane

2019 ◽  
Author(s):  
Addison E. Roush ◽  
Mohammad Riaz ◽  
Sandeep K. Misra ◽  
Scot R. Weinberger ◽  
Joshua S. Sharp
Keyword(s):  
Hydroxyl Radical ◽  
Real Time ◽  
Hydroxyl Radicals ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Photochemical Oxidation ◽  
Protein Surfaces ◽  
Radical Production ◽  
Experimental Parameters

AbstractFast Photochemical Oxidation of Proteins (FPOP) is a powerful covalent labeling tool that uses hydroxyl radicals generated by laser flash photolysis of hydrogen peroxide to footprint protein surfaces. Because radical production varies with many experimental parameters, hydroxyl radical dosimeters have been introduced to track the effective radical dosage experienced by the protein analyte. FPOP experiments performed using adenine optical radical dosimetry containing protein in Tris buffer demonstrated unusual dosimetry behavior. We have investigated the behavior of Tris under oxidative conditions in detail. We find that Tris can act as a novel gain-of-signal optical hydroxyl radical dosimeter in FPOP experiments. This new dosimeter is also amenable to inline real-time monitoring thereby allowing real-time adjustments to compensate for differences in samples for their quenching ability.

scholarly journals Iron(III) hydroxocomplex - methyl viologen dication system as a prospective tool for determination of hydroxyl radical reaction rate constants with environmental pollutants

2021 ◽  
Author(s):  
Yuliya Tyutereva ◽  
Vyacheslav P. Grivin ◽  
Jing Xu ◽  
Feng Wu ◽  
Victor Plyusnin ◽  
...  
Keyword(s):  
Hydroxyl Radical ◽  
Hydroxyl Radicals ◽  
Rate Constants ◽  
Reaction Rate ◽  
Methyl Viologen ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Radical Reaction ◽  
Reaction Rate Constants ◽  
Wide Range

Abstract Reactivity of oxidative species with target pollutants is one of the crucial parameters for application of any system based on advanced oxidation processes (AOPs). This work presents new useful approach how to determine the hydroxyl radical reaction rate constants (kOH) using UVA laser flash photolysis technique. Fe(III) hydroxocomplex at pH 3 was applied as a standard source of hydroxyl radicals and methyl viologen dication (MV2+) was used as selective probe for •OH radical. Application of MV2+ allows to determine kOH values even for compounds which do not generate themselves optically detectable transient species in reaction with hydroxyl radicals. Validity of this approach was tested on a wide range of different persistent pesticides and its main advantages and drawbacks in comparison with existing steady-state and time-resolved techniques were discussed.

On the Electrophilicity of Hydroxyl Radical:  A Laser Flash Photolysis and Computational Study

2005 ◽  
Vol 127 (19) ◽  
pp. 7094-7109 ◽  
Author(s):  
Matthew P. DeMatteo ◽  
James S. Poole ◽  
Xiaofeng Shi ◽  
Rakesh Sachdeva ◽  
Patrick G. Hatcher ◽  
...  
Keyword(s):  
Hydroxyl Radical ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Computational Study ◽  
Laser Flash

Proton transfer in phenothiazine photochemical oxidation: Laser flash photolysis and fluorescence studies

2007 ◽  
Vol 334 (1-3) ◽  
pp. 224-231 ◽  
Author(s):  
Yuhe Gao ◽  
Jiafu Chen ◽  
Xiujuan Zhuang ◽  
Jinting Wang ◽  
Yang Pan ◽  
...  
Keyword(s):  
Proton Transfer ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Photochemical Oxidation ◽  
Fluorescence Studies

Mechanism of Fe(OH)2+(aq) photolysis in aqueous solution(Technical Report)

2000 ◽  
Vol 72 (11) ◽  
pp. 2187-2197 ◽  
Author(s):  
Ivan P. Pozdnyakov ◽  
Evgeny M. Glebov ◽  
Victor F. Plyusnin ◽  
Vyacheslav P. Grivin ◽  
Yuri V. Ivanov ◽  
...  
Keyword(s):  
Aqueous Solution ◽  
Hydroxyl Radical ◽  
Flash Photolysis ◽  
Laser Flash Photolysis ◽  
Laser Flash ◽  
Photochemical Process ◽  
Technical Report

Experiments on laser flash photolysis (308 nm) of Fe(OH)2+(aq) complex in aqueous solution with addition of nitrobenzene demonstrate the formation of hydroxyl radical in the primary photochemical process.

scholarly journals Real Time Normalization of Fast Photochemical Oxidation of Proteins Experiments by Inline Adenine Radical Dosimetry

2018 ◽  
Author(s):  
Joshua S. Sharp ◽  
Sandeep K. Misra ◽  
Jeffrey J. Persoff ◽  
Robert W. Egan ◽  
Scot R. Weinberger
Keyword(s):  
Hydroxyl Radical ◽  
Real Time ◽  
Hydroxyl Radicals ◽  
Conformational Changes ◽  
Radical Scavenging ◽  
Photochemical Oxidation ◽  
Major Step ◽  
Simple Method ◽  
Radical Concentration ◽  
High Concentrations

AbstractHydroxyl radical protein footprinting (HRPF) is a powerful method for measuring protein topography, allowing researchers to monitor events that alter the solvent accessible surface of a protein (e.g. ligand binding, aggregation, conformational changes, etc.) by measuring changes in the apparent rate of reaction of portions of the protein to hydroxyl radicals diffusing in solution. Fast Photochemical Oxidation of Proteins (FPOP) offers an ultra-fast benchtop method for performing HRPF, photolyzing hydrogen peroxide using a UV laser to generate high concentrations of hydroxyl radicals that are consumed on roughly a microsecond timescale. The broad reactivity of hydroxyl radicals means that almost anything added to the solution (e.g. ligands, buffers, excipients, etc.) will scavenge hydroxyl radicals, altering their half-life and changing the effective radical concentration experienced by the protein. Similarly, minute changes in peroxide concentration, laser fluence, and buffer composition can alter the effective radical concentration, making reproduction of data challenging. Here, we present a simple method for radical dosimetry that can be carried out as part of the FPOP workflow, allowing for measurement of effective radical concentration in real time. Additionally, by modulating the amount of radical generated, we demonstrate that FPOP HRPF experiments carried out in buffers with widely differing levels of hydroxyl radical scavenging capacity can be normalized on the fly, yielding statistically indistinguishable results for the same conformer. This method represents a major step in transforming FPOP into a robust and reproducible technology capable of probing protein structure in a wide variety of contexts.

Sign in / Sign up

Export Citation Format

Share Document