Related Experiment Video
Updated: Aug 8, 2026
13:41
Monitoring Equilibrium Changes in RNA Structure by 'Peroxidative' and 'Oxidative' Hydroxyl Radical Footprinting
Published on: October 17, 2011
Pyrite-induced hydroxyl radical formation and its effect on nucleic acids
Corey A Cohn1, Steffen Mueller, Eckard Wimmer
1Department of Geosciences, Stony Brook University, Stony Brook, NY 11794, USA. corey.cohn@stonybrook.edu
Geochemical Transactions
|June 9, 2006
Summary
Pyrite exposed to water forms hydrogen peroxide, which is then converted to reactive hydroxyl radicals. This transformation, promoted by pyrite surfaces, may affect organic molecules in various environments.
Area of Science:
- Environmental Science
- Geochemistry
- Toxicology
Background:
- Pyrite (iron sulfide) is a common mineral that generates hydrogen peroxide upon contact with water.
- The potential transformation of this hydrogen peroxide into more reactive species is not fully understood.
Purpose of the Study:
- To investigate if pyrite-induced hydrogen peroxide is converted to hydroxyl radicals.
- To explore the role of dissolved iron species in this conversion process.
Main Methods:
- Electron spin resonance (ESR) spin-trapping techniques were employed.
- Scavenging reactions utilizing nucleic acids were performed.
- Experiments included the addition of ethylenediaminetetraacetic acid (EDTA) to pyrite slurries.
Main Results:
- Hydroxyl radical formation was confirmed in pyrite/aqueous suspensions.
- EDTA inhibited the conversion of hydrogen peroxide to hydroxyl radicals but not hydrogen peroxide formation.
- EDTA's inhibitory effect suggests chelation of dissolved iron species prevents the radical conversion.
Conclusions:
- The pyrite surface facilitates the conversion of hydrogen peroxide to hydroxyl radicals.
- Hydroxyl radicals can rapidly react with and transform organic molecules.
- Pyrite's presence in aqueous systems may impact organic molecule degradation and has implications for environmental and health concerns, including potential links to lung diseases from pyrite dust inhalation.
More Related Videos
12:15Quantification of three DNA Lesions by Mass Spectrometry and Assessment of Their Levels in Tissues of Mice Exposed to Ambient Fine Particulate Matter
Published on: May 29, 2019
09:59Laser-free Hydroxyl Radical Protein Footprinting to Perform Higher Order Structural Analysis of Proteins
Published on: June 4, 2021
Related Concept Videos
01:03Radical Formation: Overview
A bond can be broken either by heterolytic bond cleavage to form ions or homolytic bond cleavage to yield radicals. A fishhook arrow is used to represent the motion of a single electron in homolytic bond cleavage. There are two main sources from which radicals can be formed:
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the latter, also known...
Radicals from spin-paired molecules:
Radicals can be obtained from spin-paired molecules either by homolysis or electron transfer. While two radicals are formed in the former, an electron is added in the latter, also known...
00:54Radical Formation: Homolysis
A bond is formed between two atoms by sharing two electrons. When this bond is broken by supplying sufficient energy, either two electrons can be taken up by one atom forming ions by the cleavage called heterolysis, or the two electrons are shared by two atoms, with one each creating radicals by the cleavage called homolysis.
01:16Radical Reactivity: Nucleophilic Radicals
Radicals adjacent to electron-donating groups are called nucleophilic radicals. These radicals readily react with electrophilic alkenes. The SOMO–LUMO interactions are the driving force for the reaction, where the high-energy SOMO of the electron-rich, nucleophilic radicals interacts with the low-energy LUMO of the electron-deficient, electrophilic alkenes. Such SOMO–LUMO interactions are the basis of reactive radical traps, affecting the selectivity in radical reactions. For instance, consider...
01:30Spontaneous and Induced Mutations
Spontaneous mutations arise infrequently during DNA replication due to errors in the process. A key factor behind these errors is tautomeric shifts in nitrogenous bases, where bases transition from keto to enol forms or amino to imino forms. This shift can alter base-pairing rules, leading to mutations. Additionally, reactive oxygen species (ROS) arising from aerobic metabolism can damage DNA, resulting in depurination (loss of a purine base) or depyrimidination (loss of a pyrimidine base).
01:20Radical Autoxidation
The oxidation of an organic compound in the presence of air or oxygen is called autoxidation. For example, cumene reacts with oxygen to form hydroperoxide. Autoxidation involves initiation, propagation, and termination steps. Many organic compounds are susceptible to autoxidation—especially ethers in the presence of oxygen, which form hydroperoxides. Even though this reaction is slow, old ether bottles contain small amounts of peroxide, which leads to laboratory explosions during ether...
01:19Acid Mine Drainage
Mining activities that disturb sulfide-rich rocks, particularly those containing pyrite (FeS₂), initiate a cascade of geochemical and microbiological processes with serious environmental implications. When exposed to air and water, pyrite undergoes oxidation, releasing sulfate, ultimately forming sulfuric acid and mobilizing heavy metals into surrounding water systems. This phenomenon, known as acid mine drainage (AMD), results in low pH waters laden with toxic elements that threaten aquatic...