Search results for " Hydrogen peroxide"
showing 9 items of 19 documents
Anti-proliferative and pro-apoptotic activities of hydroxytyrosol on different tumour cells: the role of extracellular production of hydrogen peroxide
2011
Several recently published data suggest that the anti-proliferative and pro-apoptotic properties of hydroxytyrosol [3,4-dihydroxyphenyl ethanol (3,4-DHPEA)] on HL60 cells may be mediated by the accumulation of hydrogen peroxide (H2O2) in the culture medium. The aim of this study was to clarify the role played by H2O2 in the chemopreventive activities of 3,4-DHPEA on breast (MDA and MCF-7), prostate (LNCap and PC3) and colon (SW480 and HCT116) cancer cell lines and to investigate the effects of cell culture medium components and the possible mechanisms at the basis of the H2O2-producing properties of 3,4-DHPEA. The proliferation was measured by the MTT assay and the apoptosis by both fluores…
Development of a nanostructured sensor for monitoring oxidative stress in living cells
2018
Oxidative burden is elevated in the lung of COPD patients and is associated with aging and chronic inflammation. When overcoming physiological levels, reactive oxygen species (ROS) cause cell damage and sustain inflammation. Both lung epithelium and alveolar macrophages contribute to ROS generation. Currently, ROS generation is measured using fluorescent probes and colorimetric/fluorimetric assays. We present an amperometric nanostructured sensor for real-time detection of hydrogen peroxide (H2O2) released by living cells. The H2O2 sensing performance was evaluated through the current vs time response of platinum rod at a working potential of −0.45 V vs saturated calomel electrode acting as…
Electro-generation of H2O2 and abatement of organic pollutant in water by an electro-Fenton process in a microfluidic reactor
2013
The electro-generation of H2O2 and the abatement of the model organic pollutant Acid Orange 7 (AO7) in water by an electro-Fenton process were performed both in a conventional undivided macro cell and, for the first time, in a microfluidic reactor. Under optimized operative conditions, the reduction of oxygen in the microdevice gave rise, using graphite cathode, to a concentration of H2O2 of about 6 mM, one order of magnitude higher than that achieved in conventional cells. Similarly, when electro-Fenton was performed in the microfluidic reactor a dramatic increase of the abatement of COD was achieved with respect to that obtained in a conventional cell. Keywords: Wastewater treatments, Mic…
A Comparative Study of Poly(Azure A) Film-Modified Disposable Electrodes for Electrocatalytic Oxidation of H₂O₂: Effect of Doping Anion.
2018
In the present paper, poly(azure A) (PAA) films were electrosynthetized in the presence of different doping anions on disposable screen-printed carbon electrodes (SPCEs). The anions used included inorganic monoatomic (chloride and fluoride), inorganic polyatomic (nitrate and sulfate) and organic polyatomic (dodecyl sulfate, DS) species. The coated electrodes thus obtained were characterized by electrochemical techniques and SEM. They showed improved electrocatalytic activities towards hydrogen peroxide oxidation compared to that of a bare SPCE. In particular, the insertion of DS anions inside PAA films provided a special sensitivity to the electrocatalysis of H2O2, which endowed these elect…
Oxidative stress-driven expression of myeloperoxidase in endothelial cells results in accumulation of markers of oxidative and nitrosative stress in …
2009
Endothelial cells (ECs), are able to manage with higher concentrations of ROS as well as reactive nitrogen species, respect to the other cell types. The unbalance between oxidizing species and antioxidant cellular defences has been implicated in the pathogenesis of cardiovascular diseases. While the role of MPO in the oxidative burst is well established, the effects of this enzyme on endothelial biology have only recently come to light. MPO can interact with endothelial –derived NO causing its depletion and favouring its conversion to nitrogen dioxide radical, a compound responsible of protein nitration generating 3-nitrotyrosine. Moreover, MPO is the only enzyme capable to form hypoclorous…
Nanostructured Based Electrochemical Sensors.
2019
In this work, we present some results concerning the electrochemical behavior of nanostructured-based electrochemical sensors. In particular, the attention has been focused on Pd and Cu nanowires for detection of hydrogen peroxide and NiO thin film or Ni@NiO core–shell nanowires for detection of mercury ions. Ordered array of Pd and Cu nanowires was obtained through displacement deposition reaction in a commercial polycarbonate membrane acting as a template. The method leads to stable nanostructured electrodes of Pd and Cu with high surface area. For the detection of mercury ions, we have fabricated a Ni/NiO electrochemical sensor, obtained by mild thermal oxidation of Ni-foil. Some results…
Reduction of tris(benzene-1,2-dithiolate)molybdenum(VI) by hydroxide ions in dry tetrahydrofuran solution.
2001
Tris(benzene-1,2-dithiolate)molybdenum(VI) reacts rapidly and quantitatively with tetrabutylammonium hydroxide to yield the corresponding Mo(V) and Mo(IV) complexes and hydrogen peroxide; the reaction has been executed in dry tetrahydrofuran where the reaction rate shows a fair dependence on complex and OH2 concentrations. Cervilla Avalos, Antonio, Antonio.Cervilla@uv.es ; Perez Pla, Francisco, Francisco.Perez@uv.es ; Llopis Jover, Elisa, Elisa.Llopis@uv.es