Hydrogen peroxide

About: Hydrogen peroxide is a research topic. Over the lifetime, 42583 publications have been published within this topic receiving 1043732 citations. The topic is also known as: H2O2 & dioxidane.

Determination of main species involved in the first steps of TiO2 photocatalytic degradation of organics with the use of scavengers: The case of ofloxacin

Abstract: With the aid of different scavengers species involved in the first steps of TiO2/UVA (black light) photocatalytic elimination of ofloxacin (OFX) in water have been investigated. The effect of the presence of scavengers of hydroxyl radicals in bulk water (t-butanol), oxidant holes (h+) (2-propanol, iodide and oxalate), singlet oxygen (azide), electrons (oxygen) and superoxide ion radical (p-benzoquinone and tiron) has been checked at pH 7 with 0.03 M HClO4/ClO4− aerated media. The main elimination pathway leads to the formation of OFX + and takes place through an electronic transfer between the antibiotic and the catalyst surface. OFX + further reacts with O2 − leading to the reductive demethylation of OFX and generates 1 mole of hydrogen peroxide and ∼1 mole of formaldehyde per mole of OFX eliminated. The presence of phosphate promotes a change in the pathway degradation, possibly favoring the generation of HO radicals as well as the participation of this species on the oxidative demethylation of OFX and therefore reduces the production of H2O2. Therefore, OFX can be photocatalytically reduced and/or oxidized depending on the experimental conditions.

Utilizing a CdTe Quantum Dots−Enzyme Hybrid System for the Determination of Both Phenolic Compounds and Hydrogen Peroxide

Abstract: In this paper, we attempt to construct a simple and sensitive detection method for both phenolic compounds and hydrogen peroxide, with the successful combination of the unique property of quantum dots and the specificity of enzymatic reactions. In the presence of H2O2 and horseradish peroxidase, phenolic compounds can quench quantum dots' photoluminescence efficiently, and the extent of quenching is severalfold to more than 100-fold increase. Quinone intermediates produced from the enzymatic catalyzed oxidation of phenolic compounds were believed to play the main role in the photoluminescence quenching. Using a quantum dots−enzyme system, the detection limits for phenolic compounds and hydrogen peroxide were detected to be ∼10-7 mol L-1. The coupling of efficient quenching of quantum dot photoluminescence by quinone and the effective enzymatic reactions make this a simple and sensitive method for phenolic compound detection and great potential in the development of H2O2 biosensors for various analytes.