Hydrogen peroxide detection
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A novel approach for the assembly of Sn-based metal organic framework (Sn-MOF) via solvothermal method and its composite (Sn-MOF@CNT) with electroactive material, carbon nanotubes (CNT) by sonochemical means, is described that is useful for hydrogen peroxide sensing; large surface area and pore volume of Sn-MOF were exploited where in the crystallinity of the Sn-MOF was preserved upon inclusion of CNT over its surface. The surface morphology and structural analysis of Sn-MOF and its composite form, Sn-MOF@CNT, were determined analytically through Fourier-transform infrared spectroscopy (FT-IR), X-ray powder diffraction (XRD), Scanning electron microscopy (SEM), Brunauer-Emmett-Teller and Energy-dispersive X-ray spectroscopy (EDX). The developed Sn-MOF@CNT sensor was expansively used to determine and optimize the effect of scan rate, concentration and detection limits including the EDX and SEM analysis of used Sn-MOF@CNT nanocomposite's post hydrogen peroxide sensing. The electrochemical sensing with Sn-MOF@CNT revealed a lower limit of detection ~4.7 × 10-3 μM with wide linear range between 0.2 μM and 2.5 mM. This study has explored a new strategy for the deposition of CNT over Sn-MOF via a simple sonochemical methodology for successful electrochemical detection of H2O2, an approach that can be imitated for other applications.
This review deals with a survey of analytical methods for the determination of hydrogen peroxide. Since high concentrations of this simple compound may cause diseases connected with oxidative stress like cancer, cardiovascular disorders, and Alzheimer disease, its monitoring is very essential. Therefore, cheap, sensitive, selective and fast electrochemical methods are desirable for its detection. Various electrode materials based on carbon, silver, gold and platinum are described here, as well as their applications to analysis of various samples. Biosensing applications with ultramicroelectrodes allow one to detect H2O2 directly in cells which helps to understand in depth their oxidative stress and other processes connected with the production of hydrogen peroxide.
High temperature can change the effects of intra- and intercellular regulators and therefore modify the cellular response to hypoxia. We investigated H2O2 production by alveolar macrophages, isolated from adult male rats, which were incubated under conditions of oxygen deficiency and high temperature (experiment in vitro). The incubation of these cells for 2 hours at 10 % or 5 % oxygen led only to slight fluctuations in the H2O2 level, while the rise of temperature from 37?C up to 42?C significantly increased its generation. Level of thiobarbituric acid-reactive substances (TBARS) underwent similar changes. Under these conditions the accumulation of H2O2 was found to be caused mainly by its decreased cleavage rather than its enhanced production. This is indicated by decreased catalase and glutathione peroxidase activity together with a parallel absence of significant changes in superoxide dismutase (SOD) activity. Slight fluctuation of reduced glutathione level and the pronounced increase of glucose-6-phosphate dehydrogenase (G6PD) activity were detected. Strong (5 %) but not moderate (10 %) lack of oxygen led to a sharp increase in formation of cellular nitrite ions by alveolar macrophages. In general, our data showed that high temperature did not lead to any qualitative shifts of defined hypoxia-derived changes in oxidant/antioxidant balance in alveolar macrophages, but promoted sensitivity of cells to oxygen shortage.
- MeSH
- alveolární makrofágy imunologie metabolismus MeSH
- dusitany imunologie metabolismus MeSH
- financování vládou MeSH
- hypoxie buňky fyziologie imunologie MeSH
- interpretace statistických dat MeSH
- peroxid vodíku imunologie metabolismus škodlivé účinky MeSH
- poruchy vyvolané tepelným stresem komplikace metabolismus MeSH
- potkani Wistar anatomie a histologie imunologie metabolismus MeSH
- volné radikály imunologie metabolismus škodlivé účinky MeSH
- zvířata MeSH
- Check Tag
- zvířata MeSH
- Publikační typ
- srovnávací studie MeSH
Hydrogen peroxide promotes seed germination, but the molecular mechanisms underlying this process are unclear. This study presents the results of eggplant (Solanum melongena) germination analyses conducted at two different temperatures and follows the effect of hydrogen peroxide treatment on seed germination and the seed proteome. Hydrogen peroxide was found to promote eggplant germination in a way not dissimilar to that of increased temperature stimuli. LC-MS profiling detected 729 protein families, 77 of which responded to a temperature increase or hydrogen peroxide treatment. These differentially abundant proteins were found to be involved in a number of processes, including protein and amino acid metabolism, carbohydrate metabolism, and the glyoxylate cycle. There was a very low overlap between hydrogen peroxide and temperature-responsive proteins, highlighting the differences behind the seemingly similar outcomes. Furthermore, the observed changes from the seed proteome indicate that hydrogen peroxide treatment diminished the seed endogenous hydrogen peroxide pool and that a part of manifested positive hydrogen peroxide effect might be related to altered sensitivity to abscisic acid.
- MeSH
- chromatografie kapalinová MeSH
- fyziologický stres účinky léků MeSH
- hmotnostní spektrometrie MeSH
- klíčení účinky léků MeSH
- metabolismus sacharidů účinky léků MeSH
- peroxid vodíku farmakologie MeSH
- regulace genové exprese u rostlin účinky léků MeSH
- rostlinné proteiny metabolismus MeSH
- Solanum melongena účinky léků fyziologie MeSH
- teplota MeSH
- vývojová regulace genové exprese účinky léků MeSH
- Publikační typ
- časopisecké články MeSH
Mitochondrial respiratory chain enzyme Complexes are present in placenta at proportion similar to other tissues with exception of glycerophosphate dehydrogenase (mGPDH) which is expressed at a very high rate. As shown by Western blot quantification and respiratory chain enzyme activity measurements, the specific content of mGPDH is similar to that of succinate dehydrogenase or NADH dehydrogenase. Using fluorometric probe dichlorodihydrofluorescein diacetate we found that placental mitochondria display high rate of glycerophosphate-dependent hydrogen peroxide production. This was confirmed by oxygraphic detection of glycerophosphate-induced, KCN- or antimycin A-insensitive oxygen uptake. Hydrogen peroxide production by mGPDH was highly activated by one-electron acceptor, potassium ferricyanide and it was depressed by inhibitors of mGPDH and by cytochrome c. Our results indicate that mGPDH should be considered as an additional source of reactive oxygen species participating in induction of oxidative stress in placenta.
- MeSH
- financování organizované MeSH
- glycerolfosfátdehydrogenasa metabolismus MeSH
- křečci praví MeSH
- krysa rodu rattus MeSH
- kyslík metabolismus MeSH
- lidé MeSH
- mitochondrie enzymologie MeSH
- oxidoreduktasy metabolismus MeSH
- peroxid vodíku metabolismus MeSH
- placenta enzymologie MeSH
- reaktivní formy kyslíku metabolismus MeSH
- zvířata MeSH
- Check Tag
- křečci praví MeSH
- krysa rodu rattus MeSH
- lidé MeSH
- ženské pohlaví MeSH
- zvířata MeSH
High-Resolution FluoRespirometry is a well-established and versatile approach to study mitochondrial oxygen uptake amperometrically in combination with measurement of fluorescence signals. One of the most frequently applied fluorescent dyes is Amplex UltraRed for monitoring rates of hydrogen peroxide production. Selection of an appropriate mitochondrial respiration medium is of crucial importance, the primary role of which is to support and preserve optimum mitochondrial function. For harmonization of results in a common database, we compared respiration and H2O2 production of permeabilized HEK 293T cells measured in MiR05 (sucrose and K-lactobionate), Buffer Z (K-MES and KCl), MiR07 (combination of MiR05 and Buffer Z), and MiRK03 (KCl). Respiration in a simple substrate-uncoupler-inhibitor titration protocol was identical in MiR05, Buffer Z, and MiR07, whereas oxygen fluxes detected with MiRK03 were consistently lower in all coupling and electron transfer-pathway states. H2O2 production rates were comparable in all four media, while assay sensitivity was comparatively low with MiR05 and MiR07 and higher but declining over time in the other two media. Stability of assay sensitivity over experimental time was highest in MiR05 but slightly less in MiR07. Taken together, MiR05 and Buffer Z yield comparable results on respiration and H2O2 production. Despite the lower sensitivity, MiR05 was selected as the medium of choice for FluoRespirometry due to the highest stability of the sensitivity or calibration constant observed in experiments over periods of up to 2 h.
- MeSH
- buněčné dýchání MeSH
- buněčné kultury přístrojové vybavení metody MeSH
- fluorescenční barviva chemie MeSH
- fluorometrie přístrojové vybavení metody MeSH
- HEK293 buňky MeSH
- kalibrace MeSH
- kultivační média chemie MeSH
- lidé MeSH
- mitochondrie metabolismus MeSH
- myši inbrední C57BL MeSH
- myši MeSH
- oxaziny chemie MeSH
- permeabilita buněčné membrány MeSH
- peroxid vodíku metabolismus MeSH
- pufry MeSH
- senzitivita a specificita MeSH
- zvířata MeSH
- Check Tag
- lidé MeSH
- myši MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- hodnotící studie MeSH
- práce podpořená grantem MeSH
- srovnávací studie MeSH
In recent years, particles of iron in higher oxidation states (Fe(IV-VI)), commonly called ferrates, have been presented theoretically as very effective oxidants. They can potentially be used for elimination of a wide range of organic and inorganic contaminants. However, so far the majority of applications have been carried out only as laboratory tests using model samples in many cases. The application of ferrates in remediation programs has so far proved to be more complicated with results failing to meet expectations. Therefore there is a necessity to consider the suitability of their use or consider their possible combination with other agents in order to reach required removal efficiencies in remediation. This study is focused on laboratory experiments using industrial groundwater leading to the proposal of a pilot field application realized as an ex-situ remediation. The combination of ferrates with hydrogen peroxide was used in this study in order to enhance the removal efficiency during pilot remediation of groundwater strongly contaminated by a wide range of organic contaminants. This combination has been shown to be very effective. During the 24-hour reaction time the majority of detected contaminants were removed by approximately 60-80%. Moreover, the unpleasant odor of the water was suppressed and suspended particles were removed by the flocculation effect of ferric sludge.
- MeSH
- chemické látky znečišťující vodu chemie MeSH
- čištění vody metody MeSH
- laboratoře MeSH
- peroxid vodíku chemie MeSH
- pilotní projekty MeSH
- podzemní voda chemie MeSH
- regenerace a remediace životního prostředí metody MeSH
- železo chemie MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
- Geografické názvy
- Česká republika MeSH
Hydrogen peroxide and nicotinamide adenine dinucleotide (NADH) may be determined amperometrically using screen-printed electrodes chemically modified with iron(III) hexacyanoosmate(II) (Osmium purple) in flow injection analysis (FIA). The determination is based on the exploitation of catalytic currents resulting from the oxidation/reduction of the modifier. The performance of the sensor was characterized and optimized by controlling several operational parameters (applied potential, pH and flow rate of the phosphate buffer). Comparison has been made with analogous complexes of ruthenium (Ruthenium purple) and iron (Prussian blue). Taking into account the sensitivity and stability of corresponding sensors, the best results were obtained with the use of Osmium purple. The sensor exhibited a linear increase of the amperometric signal with the concentration of hydrogen peroxide in the range of 0.1-100 mg L(-1) with a detection limit (evaluated as 3sigma) of 0.024 mg L(-1) with a R.S.D. 1.5% for 10 mg L(-1) H2O2 under optimized flow rate of 0.4 mL min(-1) in 0.1M phosphate buffer carrier (pH 6) and a working potential of +0.15 V versus Ag/AgCl. Afterwards, a biological recognition element--either glucose oxidase or ethanol dehydrogenase--was incorporated to achieve a sensor facilitating the determination of glucose or ethanol, respectively. The glucose sensor gave linearity between current and concentration in the range from 1 to 250 mg L(-1) with a R.S.D. 2.4% for 100 mg L(-1) glucose, detection limit 0.02 mg L(-1) (3sigma) and retained its original activity after 3 weeks when stored at 6 degrees C. Optimal parameters in the determination of ethanol were selected as: applied potential +0.45 V versus Ag/AgCl, flow rate 0.2 mL min(-1) in 0.1 M phosphate buffer carrier (pH 7). Different structural designs of the ethanol sensor were tested and linearity obtained was up to 1000 mg L(-1) with a maximum R.S.D. of 5.1%. Applications in food analysis were also examined.
- MeSH
- alkoholdehydrogenasa analýza MeSH
- alkoholické nápoje analýza MeSH
- analýza potravin metody MeSH
- biosenzitivní techniky metody MeSH
- elektrochemie metody MeSH
- enzymy imobilizované MeSH
- ethanol analýza MeSH
- ferrokyanidy chemie MeSH
- financování organizované MeSH
- glukosa analýza MeSH
- glukosaoxidasa analýza MeSH
- katalýza MeSH
- NAD chemie MeSH
- oxid osmičelý chemie MeSH
- peroxid vodíku chemie MeSH
- sloučeniny ruthenia chemie MeSH
- železité sloučeniny chemie MeSH
- Publikační typ
- srovnávací studie MeSH
Reports describing production of reactive oxygen species in neonatal heart are missing. As lysyl oxidase is potentially important source of H(2)O(2), we studied its role during ontogenic development of rat heart. H(2)O(2) was detected in thin sections of developing rat heart by fluorescence microscopy with the use of fluorescence probe 2'-7'-dichlorofluorescin. The experimental design comprised foetuses 21 days after conception, and then the animals sampled on the 1st, 4th, 7th, 10th, 15th, 30th and 60th day after birth. We also used 7-month-old animals as an example of ageing effects. Since the day 4 on, H(2)O(2) was produced only extracellularly up to the day 15, between days 30 and 60 intracellular production was detected as well, and in 7-month-old animals only extracellular production was observed. The specific inhibitors of lysyl oxidase almost completely quenched the H(2)O(2)-dependent fluorescence. Starting from day 7, blue autofluorescence specific to oxidized proteins developed in the vessel wall. Intracellular blue autofluorescence specific to autoxidation products developed after day 30. Chloroform extraction diminished the intracellular blue fluorescence, leaving the extracellular fluorescence intact. This confirmed the protein nature of the fluorophores. Lysyl oxidase is significant source of H(2)O(2) in the heart vessel wall during development and H(2)O(2) oxidatively modifies elastin producing protein blue autofluorescence.
- MeSH
- chloroform MeSH
- elastin metabolismus MeSH
- fluoresceiny metabolismus MeSH
- fluorescence MeSH
- fluorescenční barviva metabolismus MeSH
- krysa rodu rattus MeSH
- lysyloxidasa metabolismus MeSH
- myokard enzymologie metabolismus MeSH
- oxaziny metabolismus MeSH
- peroxid vodíku metabolismus MeSH
- potkani Wistar MeSH
- srdce růst a vývoj MeSH
- zvířata MeSH
- Check Tag
- krysa rodu rattus MeSH
- ženské pohlaví MeSH
- zvířata MeSH
- Publikační typ
- časopisecké články MeSH
- práce podpořená grantem MeSH
A simple electrochemical DNA biosensor based on a glassy carbon electrode (GCE) was prepared by adsorbing double-stranded DNA (dsDNA) onto the GCE surface and subsequently used for the detection of dsDNA damage induced by hydroxyl radicals. Investigation of the mutual interaction between hydroxyl radicals and dsDNA was conducted using a combination of several electrochemical detection techniques: square-wave voltammetry for direct monitoring the oxidation of dsDNA bases, and cyclic voltammetry and electrochemical impedance spectroscopy as indirect electrochemical methods making use of the redox-active indicator [Fe(CN)6](4-/3-). Hydroxyl radicals were generated electrochemically on the surface of a boron-doped diamond electrode and chemically (via the Fenton's reaction or the auto-oxidation of Fe(II)). The extent of dsDNA damage by electrochemically generated hydroxyl radicals depended on the current density applied to the generating electrode: by applying 5, 10, and 50mAcm(-2), selected relative biosensor responses decreased after 3min incubation from 100% to 38%, 27%, and 3%, respectively. Chemically generated hydroxyl radicals caused less pronounced dsDNA damage, and their damaging activity depended on the form of Fe(II) ions: decreases to 49% (Fenton's reaction; Fe(II) complexed with EDTA) and 33% (auto-oxidation of Fe(II); Fe(II) complexed with dsDNA) were observed after 10min incubation.
- MeSH
- adsorpce MeSH
- biosenzitivní techniky přístrojové vybavení metody MeSH
- DNA chemie genetika MeSH
- elektrochemie MeSH
- elektrody MeSH
- hydroxylový radikál farmakologie MeSH
- peroxid vodíku chemie MeSH
- poškození DNA * MeSH
- sklo chemie MeSH
- uhlík chemie MeSH
- železo chemie MeSH
- Publikační typ
- časopisecké články MeSH
