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1.
Inorg Chem ; 2020 May 22.
Artigo em Inglês | MEDLINE | ID: mdl-32441928

RESUMO

In this contribution, we report the synthesis and full characterization of the first mixed-valence Ru(II)/Ru(III) ion-pair complex, [RuII(bipy)2(pic)]+[cis-RuIIICl2(pic)2]-, in the solid state and in aqueous solution, where bipy = 2,2'-bipyridine and pic- = picolinate. In addition, unexpected high-frequency electron paramagnetic resonance evidence for interactions between two neighboring Ru(III) ions, resulting in a triplet state, S = 1, was found.

2.
Dalton Trans ; 49(15): 4599-4659, 2020 Apr 21.
Artigo em Inglês | MEDLINE | ID: mdl-32162632

RESUMO

This review covers highlights of the work performed in the van Eldik group on inorganic reaction mechanisms over the past two decades in the form of a personal journey. Topics that are covered include, from NO to HNO chemistry, peroxide activation in model porphyrin and enzymatic systems, the wonder-world of RuIII(edta) chemistry, redox chemistry of Ru(iii) complexes, Ru(ii) polypyridyl complexes and their application, relevant physicochemical properties and reaction mechanisms in ionic liquids, and mechanistic insight from computational chemistry. In each of these sections, typical examples of mechanistic studies are presented in reference to related work reported in the literature.

3.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117811, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31813731

RESUMO

The interaction of bovine serum albumin (BSA) with seven-coordination iron (II) complex containing sulfur-based macrocyclic ligand was investigated by means of UV/vis absorption spectroscopy and fluorescence quenching technique. The accurate fluorescence spectra are obtained by using Inner filter effect (IFE) correction. The apparent association constant, kapp, the number of binding sites, n, and the apparent binding constant KSV were found to be 0.95 × 103 M-1, 0.96, and 6.13 × 104 M-1, respectively. It found that BSA molecules are adsorbed on the surface of iron (II) complex by electrostatic interaction. The quenching mechanism is discussed involving energy transfer from BSA to iron (II) complex.

4.
J Biol Inorg Chem ; 24(3): 311-313, 2019 05.
Artigo em Inglês | MEDLINE | ID: mdl-30980181

RESUMO

The Commentary is in answer to the comment of a reader that objected against the use of the term 'nitroxylcobalamin' in two recent reports in JBC from our group. We use this opportunity to explain to the reader where this terminology originated from.

5.
ChemSusChem ; 12(3): 661-671, 2019 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-30427595

RESUMO

Exposure to airborne particulate matter (PM) is associated with hazardous effects on human health. Soluble constituents of PM may be released in biological fluids and disturb the precisely tuned nitric oxide signaling processes. The influence of aqueous extracts from two types of airborne urban PM (SRM 1648a, a commercially available sample, and KR PM2.5, a sample collected "in-house" in Krakow, Poland) on the stability of S-nitrosoglutathione (GSNO) was investigated. The particle interfaces had no direct effect on the studied reaction, but extracts obtained from both samples facilitated NO release from GSNO. The effectiveness of NO release was significantly affected by glutathione (GSH) and ascorbic acid (AscA). Examination of the combined influence of Cu2+ , Fe3+ , and reductants on GSNO stability revealed copper to be the main GSNO decomposing species. Computational models of nitrosothiols interacting with metal oxide substrates and solvated metal ions support these claims. The study stresses the importance of the interplay between metal ions and biological reductants in S-nitrosothiols decomposition.

Assuntos
Óxido Nítrico/química , Material Particulado/química , S-Nitrosoglutationa/química , Transdução de Sinais , Ácido Ascórbico/química , Cobre/química , Compostos Férricos/química , Glutationa/química , Humanos
6.
Environ Pollut ; 238: 638-646, 2018 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-29614473

RESUMO

Particulate matter (PM) can strongly affect redox biochemistry and therefore induce the response of the immune system and aggravate the course of autoimmune diseases. Nanoparticles containing transition metal compounds possessing semiconductor properties (TiO2, ZnO) may act as photocatalysts and accelerate the generation of reactive oxygen species (ROS) and reactive nitrogen species (RNS). In this study, the NIST standard reference material, SRM 1648a, has been analyzed in terms of this consideration. Organic compounds present in SRM 1648a were removed by cold oxygen plasma treatment. Samples of SRM 1648a with removed organic content (<2% of organic carbon, <1% of nitrogen) were obtained within 2â¯h of this treatment. The treatment did not affect the morphology of the powder. The reference material and PM2.5 collected in Kraków are composed of smaller particles and nanoparticles forming aggregates. The efficiency of (photo)generation of hydroxyl radicals and singlet oxygen was compared for original and organics-free samples. The analyzed samples showed the highest activity towards ROS generation when exposed to UV-vis-NIR light, moderate under UV irradiation, and the lowest in dark. Data collected in the present study suggest that the organic fraction is mostly responsible for singlet oxygen generation, as almost twice higher efficiency of 1O2 generation was observed for the original NIST sample compared to the material without the organic fraction. However, particulate matter collected in Kraków was found to have a five times higher activity in singlet oxygen generation (compared for original NIST and Kraków dust samples).

Assuntos
Poluentes Atmosféricos/química , Radical Hidroxila/química , Modelos Químicos , Material Particulado/análise , Oxigênio Singlete/química , Poluentes Atmosféricos/análise , Poeira , Radical Hidroxila/análise , Nitrogênio , Compostos Orgânicos , Oxirredução , Oxigênio , Material Particulado/química , Espécies Reativas de Oxigênio , Raios Ultravioleta
7.
J Biol Inorg Chem ; 23(3): 377-383, 2018 05.
Artigo em Inglês | MEDLINE | ID: mdl-29435646

RESUMO

Despite detailed studies on nitroxylcobalamin (CblNO) formation, the possible intracellular generation of CblNO via reduction of nitrocobalamin (CblNO2) remains questionable. To study this further, spectroscopic studies on the reaction of CblNO2 with the intracellular antioxidant ascorbic acid (HAsc-) were performed in aqueous solution at pH < 5.0. It was found that nitroxylcobalamin is the final product of this interaction, which is not just a simple reaction but a rather complex chemical process. We clearly show that an excess of nitrite suppresses the formation of CblNO, from which it follows that ascorbic acid cannot reduce coordinated nitrite. We propose that under the influence of ascorbic acid, nitrocobalamin is reduced to Cbl(II) and nitric oxide (·NO), which can subsequently react rapidly to form CblNO. It was further shown that this system requires anaerobic conditions as a result of the rapid oxidation of both Cbl(II) and CblNO.

Assuntos
Ácido Ascórbico/química , Metaloporfirinas/química , Vitamina B 12/análogos & derivados , Concentração de Íons de Hidrogênio , Nitritos/química , Espectrofotometria Ultravioleta , Vitamina B 12/química
8.
Angew Chem Int Ed Engl ; 57(3): 663-667, 2018 01 15.
Artigo em Inglês | MEDLINE | ID: mdl-29194889

RESUMO

Colloidal coordination compounds in the sub-micrometer range were synthesized from a chloro gold(I) carbene complex via the anti-solvent procedure and stabilized by a surfactant shell of Tween 20. This compound was successfully applied as model system to monitor heterogeneous multiphase ligand substitution reactions at the solid-liquid interface.

9.
Phys Chem Chem Phys ; 20(2): 1286-1292, 2018 Jan 03.
Artigo em Inglês | MEDLINE | ID: mdl-29251313

RESUMO

The thermal cis-to-trans isomerisation reaction of a series of hydroxy-substituted azo derivatives was studied kinetico-mechanistically as a function of temperature and pressure in order to investigate the possible role of the solvent in controlling the isomerisation mechanism, viz. inversion versus rotation. The variation of the observed first order rate constants for kinetic runs carried out at different temperatures and pressures was used to determine the thermal activation parameters ΔH and ΔS, and the pressure activation parameter ΔV. In addition, some experiments with deuterated species or solvents were also performed. The reported results could be interpreted as indicative of a changeover from an inversion mechanism for non-polar solvents to a rotational mechanism for polar solvents, capable of hydrogen bonding, for some of the systems studied. However, the operation of a rotational mechanism in all studied cases can account more consistently for the data observed.

10.
Chemosphere ; 187: 430-439, 2017 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-28865356

RESUMO

Submicron particulate matter containing particles with an aerodynamic diameter ≤1 µm (PM1) are not monitored continuously by Environmental Protection Agencies around the World and are seldom studied. Numerous studies have indicated that people exposed to ultrafine (≤100 nm), submicron and fine particulate matter containing particles with an aerodynamic diameter ≤2.5 µm (PM2.5), can suffer from respiratory track diseases, cardiovascular, immunological or heart diseases and others. Inorganic pollutants containing redox active transition metals and small gaseous molecules, are involved in the generation of reactive oxygen and reactive nitrogen species. Inhalation of this kind of particles can affect immune-toxicity. Environmental pollution may aggravate the course of autoimmune diseases, in particular influence the mechanisms of the autoimmune system. Important factors that influence the toxicity of particulate matter, are particle size distribution, composition and concentration. This report deals with the composition of PM1 and PM2.5 fractions collected in Krakow, Poland. In spring 2015, the mean concentrations of PM1 and PM2.5 were 19 ± 14 and 27 ± 19 µg/m3, respectively. The PM2.5 fraction contained approximately 70 ± 17% of submicron particulate matter. In spring 2016, the mean concentrations of PM1 and PM2.5 were 12 ± 5 and 22 ± 12 µg/m3, respectively. The PM2.5 fraction contained approximately 60 ± 15% of submicron particulate matter. The concentrations of the elements Cl, K, Ca, Ti, Cr, Mn, Fe, Ni, Cu, Zn, Br, Rb, Sr and Pb in both fractions were determined by X-ray fluorescence spectrometry. Most of the analyzed metals had higher concentrations in the fine fraction than in the submicron one. Concentrations of V and As were below the detection limit in both fractions, whereas concentrations of Mn and Ca were below the detection limits in the PM1 fraction. The results are discussed in terms of the consequences they may have on the APARIC project presently underway in Krakow.

Assuntos
Poluentes Atmosféricos/análise , Material Particulado/química , Monitoramento Ambiental/métodos , Exposição por Inalação/efeitos adversos , Metais/análise , Tamanho da Partícula , Material Particulado/análise , Material Particulado/toxicidade , Polônia , Estações do Ano , Espectrometria por Raios X
11.
Dalton Trans ; 46(31): 10264-10280, 2017 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-28737821

RESUMO

The crystal structures of [RuII(terpy)(bipy)Cl]Cl·2H2O and [RuII(terpy)(en)Cl]Cl·3H2O, where terpy = 2,2':6',2''-terpyridine, bipy = 2,2'-bipyridine and en = ethylenediamine, were determined and compared to the structure of the complexes in solution obtained by multi-nuclear NMR spectroscopy in DMSOd-6 as a solvent. In aqueous solution, both chlorido complexes aquate fully to the corresponding aqua complexes, viz. [RuII(terpy)(bipy)(H2O)]2+ and [RuII(terpy)(en)(H2O)]2+, within ca. 2 h and ca. 2 min at 37 °C, respectively. The spontaneous aquation reactions can only be suppressed by chloride concentrations as high as 2 to 4 M, i.e. concentrations much higher than that found in human blood. The corresponding aqua complexes are characterized by pKa values of ca. 10 and 11, respectively, which suggest a more labile coordinated water molecule in the case of the [RuII(terpy)(en)(H2O)]2+ complex. Substitution reactions of the aqua complexes with chloride, cyanide and thiourea show that the [RuII(terpy)(en)(H2O)]2+ complex is 30-60 times more labile than the [RuII(terpy)(bipy)(H2O)]2+ complex at 25 °C. Water exchange reactions for both complexes were studied by 17O-NMR and DFT calculations (B3LYP(CPCM)/def2tzvp//B3LYP/def2svp and ωB97XD(CPCM)/def2tzvp//B3LYP/def2svp). Thermal and pressure activation parameters for the water exchange and ligand substitution reactions support the operation of an associative interchange (Ia) process. The difference in reactivity between these complexes can be accounted for in terms of π-back bonding effects of the terpy and bipy ligands and steric hindrance on the bipy complex. Consequences for eventual biological application of the chlorido complexes are discussed.

12.
Inorg Chem ; 55(10): 5037-40, 2016 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-27111693

RESUMO

The reaction of hydrogen sulfide (H2S) and nitric oxide (NO) is of great physiological significance in human organisms. Our present studies show that Ru(III)(edta) (edta(4-) = ethylenediaminetetraacetate) mediates the S-nitrosylation of bisulfide ion (HS(-)) using NO to form [Ru(III)(edta)(SNO)](2-), the first-ever example of a ruthenium complex containing thionitrite (SNO(-)) in aqueous solution. The reaction product [Ru(III)(edta)(SNO)](2-) was characterized by IR, electron paramagnetic resonance, and electrospray ionization mass spectroscopy. Our studies further show that formation of the putative thionitrous acid coordinated to Ru(III)(edta) does not occur via the reaction of [Ru(III)(edta)NO](-) with HS(-).

13.
Chemistry ; 21(43): 15201-10, 2015 Oct 19.
Artigo em Inglês | MEDLINE | ID: mdl-26353996

RESUMO

The hydroperoxo iron(III) intermediate P450cam Fe(III) -OOH, being the true Compoundâ0 (Cpdâ0) involved in the natural catalytic cycle of P450cam , could be transiently observed in the peroxo-shunt oxidation of the substrate-free enzyme by hydrogen peroxide under mild basic conditions and low temperature. The prolonged lifetime of Cpdâ0 enabled us to kinetically examine the formation and reactivity of P450cam Fe(III) -OOH species as a function of varying reaction conditions, such as pH, and concentration of H2 O2 , camphor, and potassium ions. The mechanism of hydrogen peroxide binding to the substrate-free form of P450cam differs completely from that observed for other heme proteins possessing the distal histidine as a general acid-base catalyst and is mainly governed by the ability of H2 O2 to undergo deprotonation at the hydroxo ligand coordinated to the iron(III) center under conditions of pH≥p${K{{{\rm P450}\hfill \atop {\rm a}\hfill}}}$. Notably, no spectroscopic evidence for the formation of either CpdâI or CpdâII as products of heterolytic or homolytic Oï£¿O bond cleavage, respectively, in Cpdâ0 could be observed under the selected reaction conditions. The kinetic data obtained from the reactivity studies involving (1R)-camphor, provide, for the first time, experimental evidence for the catalytic activity of the P450Fe(III) -OOH intermediate in the oxidation of the natural substrate of P450cam .

14.
J Biol Inorg Chem ; 20(6): 1069-78, 2015 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-26246372

RESUMO

The interaction with nitric oxide (NO) is an important aspect of the biological activity of vitamin B12 (Cbl). Whereas the formation of nitroxylcobalamin (CblNO) via the binding of NO to reduced CblCo(II) has been studied in detail before, the possible intracellular formation of CblNO via reduction of nitrocobalamin (CblNO2) is still questionable. To study this further, spectroscopic and kinetic studies on the reaction of CblNO2 with the intracellular antioxidant ascorbic acid (Asc) were performed in aqueous solution at the physiological pH of 7.2. It was found that the redox pathway of this reaction requires anaerobic conditions as a result of the rapid re-oxidation of reduced CblCo(II). In the studied system, both CblOH2 and CblNO2 are reduced to CblCo(II) by ascorbate at pH 7.2, the CblOH2 complex being two orders of magnitude more reactive than CblNO2. Clear evidence for redox cycling between CblOH2/CblNO2 and CblCo(II) under aerobic conditions was observed as an induction period during which all oxygen was used prior to the formation of CblCo(II) in the presence of an excess of ascorbate. No evidence for the intermediate formation of CblNO or NO radicals during the reduction of CblNO2 could be found. Nitrocob(III)alamin can be reduced by ascorbic acid under physiological conditions. The products of the reaction are cob(II)alamin and nitrite ion. This reaction is ca. 200 times slower than the one involving aquacob(III)alamin.

Assuntos
Ácido Ascórbico/química , Ácido Ascórbico/metabolismo , Vitamina B 12/análogos & derivados , Concentração de Íons de Hidrogênio , Cinética , Modelos Moleculares , Oxirredução , Oxigênio/química , Vitamina B 12/química , Vitamina B 12/metabolismo
15.
Dalton Trans ; 44(31): 14110-21, 2015 Aug 21.
Artigo em Inglês | MEDLINE | ID: mdl-26172408

RESUMO

A series of copper(ii) complexes, viz. [Tp(MeMe)Cu(Cl)(H2O)] (), [Tp(MeMe)Cu(OAc)(H2O)] (), [Tp(MeMe)Cu(NO3)] () and [Tp(MeMe)Cu(ClO4)] () containing tris(3,5-dimethylpyrazolyl)borate (KTp(MeMe)), have been synthesized and fully characterized. The substitution reaction of with thiourea was studied under pseudo-first-order conditions as a function of concentration, temperature and pressure in methanol and acetonitrile as solvents. Two reaction steps that both depended on the nucleophile concentration were observed for both solvents. Substitution of coordinated methanol is about 40 times faster than the substitution of chloride. In acetonitrile, the rate constant for the displacement of coordinated acetonitrile was more than 20 times faster than the substitution of chloride. The reported activation parameters indicate that both reaction steps follow a dissociative mechanism in both solvents. On going from methanol to acetonitrile, the rate constant for the displacement of the solvent becomes more than 200 times faster due to the more labile acetonitrile, but the substitution mechanism remained to have a dissociative character. The antioxidant activities of were evaluated for superoxide dismutase (SOD), glutathione-s-transferase (GST0 and glutathione reduced (GSH-Rd) activity. and were found to show (p < 0.05) the highest antioxidant activity in comparison to and , which can be ascribed to the geometric configuration as well as the nature of the co-ligand. showed catechol oxidase activity with turnover numbers of 20 min(-1) and a coordination affinity for 3,5-DTBC of K1, = 31 mM(-1). K1 is rather large and seems to be typical for faster biomimetic models, and also for the enzyme itself (25 mM(-1)). The reaction rate depended linearly on the complex concentration, indicating a first-order dependence on the catalyst concentration.

Assuntos
Antioxidantes/metabolismo , Materiais Biomiméticos/química , Boratos/química , Cobre/química , Compostos Organometálicos/química , Oxirredutases/metabolismo , Pirazóis/química , Catálise , Catecol Oxidase/metabolismo , Cinética , Ligantes , Oxirredução , Análise Espectral , Termodinâmica
16.
Chemistry ; 21(25): 9083-92, 2015 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-25924594

RESUMO

Cytochrome P450 enzymes are highly versatile biological catalysts in our body that react with a broad range of substrates. Key functions in the liver include the metabolism of drugs and xenobiotics. One particular metabolic pathway that is poorly understood relates to the P450 activation of aliphatic groups leading to either hydroxylation or desaturation pathways. A DFT and QM/MM study has been carried out on the factors that determine the regioselectivity of aliphatic hydroxylation over desaturation of compounds by P450 isozymes. The calculations establish multistate reactivity patterns, whereby the product distributions differ on each of the spin-state surfaces; hence spin-selective product formation was found. The electronic and thermochemical factors that determine the bifurcation pathways were analysed and a model that predicts the regioselectivity of aliphatic hydroxylation over desaturation pathways was established from valence bond and molecular orbital theories. Thus, the difference in energy of the Oï£¿H versus the Oï£¿C bond formed and the π-conjugation energy determines the degree of desaturation products. In addition, environmental effects of the substrate binding pocket that affect the regioselectivities were identified. These studies imply that bioengineering P450 isozymes for desaturation reactions will have to include modifications in the substrate binding pocket to restrict the hydroxylation rebound reaction.

Assuntos
Sistema Enzimático do Citocromo P-450/metabolismo , Xenobióticos/metabolismo , Biocatálise , Sistema Enzimático do Citocromo P-450/química , Hidroxilação , Teoria Quântica , Termodinâmica , Xenobióticos/química
17.
Dalton Trans ; 44(13): 6012-22, 2015 Apr 07.
Artigo em Inglês | MEDLINE | ID: mdl-25720308

RESUMO

The nature of chlorophyll interactions with copper(II) ions varies considerably in organic solvents, depending on the dominant coordinative form. Besides formation of the metallo tetrapyrrolic complex, Cu(II) ions can cause oxidation of the pigment, reversible or irreversible, which can lead to the destruction of the macrocyclic structure. All these reaction types can be distinguished within a quite narrow range of reaction conditions. The ability to form new metallo derivatives in either metalation or transmetalation reactions is obviously limited by the concentration of the potential oxidant, but can be secured below this level via suitable composition of the reaction system. The decisive factor in the selection of a specific reaction pathway is the presence of a potential ligand that can affect the reactivity of Cu(II) for example by shifting its redox potential. Spectroscopic and electrochemical studies were performed in order to determine the predominant species of Cu(II) in methanol, nitromethane and acetonitrile in the presence of chloride and acetate ions, as well as to assign their appropriate oxidizing ability. This allowed us to estimate the boundary conditions for the electron transfer processes in chlorophyll-Cu(II) systems. Chlorophyll and its free base can undergo both types of electron transfer processes, however, they reveal different susceptibilities that make this class of ligands quite versatile markers in tuning the reactivity of metal ions in solutions.

Assuntos
Clorofilídios/química , Complexos de Coordenação/química , Cobre/química , Metano/química , Solventes/química , Estrutura Molecular , Oxirredução
18.
Anal Bioanal Chem ; 407(11): 3023-34, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-25410641

RESUMO

Candidate reference materials (RM) for the analysis of phosphorus-based flame retardants in styrene-based polymers were prepared using a self-made mini-extruder. Due to legal requirements of the current restriction for the use of certain hazardous substances in electrical and electronic equipment, focus now is placed on phosphorus-based flame retardants instead of the brominated kind. Newly developed analytical methods for the first-mentioned substances also require RMs similar to industrial samples for validation and verification purposes. Hence, the prepared candidate RMs contained resorcinol-bis-(diphenyl phosphate), bisphenol A bis(diphenyl phosphate), triphenyl phosphate and triphenyl phosphine oxide as phosphorus-based flame retardants. Blends of polycarbonate and acrylonitrile-co-butadiene-co-styrene as well as blends of high-impact polystyrene and polyphenylene oxide were chosen as carrier polymers. Homogeneity and thermal stability of the candidate RMs were investigated. Results showed that the candidate RMs were comparable to the available industrial materials. Measurements by ICP/OES, FTIR and NMR confirmed the expected concentrations of the flame retardants and proved that analyte loss and degradation, respectively, was below the uncertainty of measurement during the extrusion process. Thus, the candidate RMs were found to be suitable for laboratory use.

19.
Chem Commun (Camb) ; 50(93): 14562-5, 2014 Dec 04.
Artigo em Inglês | MEDLINE | ID: mdl-25307989

RESUMO

Reported is the first example of a ruthenium(III) complex, Ru(III)(edta) (edta(4-) = ethylenediaminetetraacetate), that catalyzes the disproportion of H2O2 to O2 and water in resemblance to catalase activity, and shedding light on the possible mechanism of action of the [Ru(V)(edta)(O)](-) formed in the reacting system.

Assuntos
Catalase/metabolismo , Compostos Organometálicos/metabolismo , Rutênio/metabolismo , Materiais Biomiméticos/química , Materiais Biomiméticos/metabolismo , Catálise , Peróxido de Hidrogênio/química , Peróxido de Hidrogênio/metabolismo , Estrutura Molecular , Compostos Organometálicos/química , Oxigênio/química , Oxigênio/metabolismo , Rutênio/química , Água/química , Água/metabolismo
20.
Dalton Trans ; 43(48): 18042-6, 2014 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-25351826

RESUMO

Reported here is the first example of a ruthenium(iii) complex [Ru(III)(EDTA)(H2O)](-) (EDTA(4-) = ethylenediaminetetraacetate) that mediates S-nitrosylation of cysteine in the presence of nitrite at pH 4.5 (acetate buffer) and results in the formation of [Ru(III)(EDTA)(SNOCy)](-). The kinetics of the reaction was studied by stopped-flow and rapid-scan spectrophotometry as a function of [Cysteine], [NO2(-)] and pH (3.5-8.5). Formation of [Ru(III)(EDTA)(SNOCy)](-), the product of the S-nitrosylation reaction, was identified by ESI-MS experiments. A working mechanism in agreement with the spectroscopic and kinetic data is presented.

Assuntos
Complexos de Coordenação/química , Cisteína/química , Ácido Edético/química , Nitritos/química , Rutênio/química , Concentração de Íons de Hidrogênio , Cinética , Espectrofotometria