Valence Form Research Articles

A Hypothesis on the Function of High‐Valent Fe in NiFe (Hydr)oxide in the Oxygen‐Evolution Reaction

This study investigated the dynamic changes in NiFe (hydr)oxide and identified the role of high‐valent Fe in the oxygen‐evolution reaction (OER) within alkaline media via in‐situ techniques. Several high‐valent Fe ions were found to remain considerably stable in the absence of potential in NiFe (hydr)oxide, even 96 hours after the OER. For Ni2+ hydroxide treated with 57Fe ions, where Fe sites are introduced onto the surface of Ni2+ hydroxide, no Fe4+ species were detected at the rate‐determining step (RDS). The findings of this study suggested that the oxidation of bulk Fe ions, similar to Ni ions, to high valent forms, is charge accumulation without a direct role in OER; these results offered a novel perspective on manipulating Fe states to optimize OER efficacy. The prevailing hypothesis suggested that trace amounts of high‐valent Fe ions, notably those on the surface, directly participate in OER.

A Hypothesis on the Function of High-Valent Fe in NiFe (Hydr)oxide in the Oxygen-Evolution Reaction.

This study investigated the dynamic changes in NiFe (hydr)oxide and identified the role of high-valent Fe in the oxygen-evolution reaction (OER) within alkaline media via in-situ techniques. Several high-valent Fe ions were found to remain considerably stable in the absence of potential in NiFe (hydr)oxide, even 96 hours after the OER. For Ni2+ hydroxide treated with 57Fe ions, where Fe sites are introduced onto the surface of Ni2+ hydroxide, no Fe4+ species were detected at the rate-determining step (RDS). The findings of this study suggested that the oxidation of bulk Fe ions, similar to Ni ions, to high valent forms, is charge accumulation without a direct role in OER; these results offered a novel perspective on manipulating Fe states to optimize OER efficacy. The prevailing hypothesis suggested that trace amounts of high-valent Fe ions, notably those on the surface, directly participate in OER.

Aqueous dispersions of ‘green’ silver nanoparticles for eco-applications: Synthesis, structure and biosafety

Sustainable agriculture requires the use of intelligent compounds with multifaceted effect on soil and plants. Such conditioners can be hydrogels enriched with nanoparticles, but only those synthesized using ‘green chemistry’ methods. Therefore, the main aim of the study was to synthesize and characterize innovative ‘green’ silver nanoparticles (AgNPs) for agricultural applications. AgNPs were created using water or alcohol extracts of eucalyptus (Eucalyptus viminalisLabill) and aloe (Aloë arborescens Mill) as well as tannin to reduce silver ions (Ag+) to zero valent form (Ag0). The synthesis was conducted under autoclave conditions or at room temperature, in the presence of potassium carbonate. The AgNPs characterization was performed by X-ray diffraction (XRD), scanning electron microscopy (SEM), transmission electron microscopy (TEM) and dynamic light scattering (DLS) method, whereas stability of the AgNPs suspensions under various conditions was estimated using turbidimetry. Biosafety of the formed species was determined based on genotoxicity (comet test) and cytotoxicity (study with crystal violet and MTT) assays. The obtained results confirmed the presence of zero valent silver phase in the nanoparticles and showed that their crystallite size was 14–24 nm, with different degrees of polydispersity depending on the synthesis conditions. Hydrodynamic diameter of AgNPs and their aggregates in the aqueous dispersions varied from 6 nm to 103 nm, and the smallest aggregation degree was noted for the nanoparticles synthesized using tannin. All synthesized nanoparticles were biosafe. Thus, they can be applied in agro-industrial processes without damaging the environment.

Translocation and transformation of uranium along the aquatic food chain: New insights into uranium risks to the environment

Uranium pollution in aquatic ecosystems poses a threat to organisms. However, the metabolism and toxicity of uranium along aquatic food chains remain unknown. Here, we established an artificial aquatic ecosystem to investigate the fate of uranium along the food chain and reveal its potential toxicity. The results displayed a dose– and time–dependent toxicity of uranium on algae, leading to cell deformation and impeding cell proliferation. When uranium-exposed algae are ingested by fish, uranium tends to concentrate in the intestinal system and bones of fish. Comparatively, direct water uranium exposure resulted in a remarkable uranium accumulation in the head, skin, and muscles of fish, suggesting different toxicity depending on distinct exposure pathways. High–level uranium pollution (20 mg L−1) intensifies the toxicity to fish through food intake compared to direct water exposure. It has also revealed that approximately 25 % and 20 % of U(VI) were reduced to lower valence forms during its accumulation in algae and fish, respectively, and over 10 % of U(IV, VI) converted to U(0) ultimately, through which uranium toxicity was mitigated due to the lower solubility and bioavailability. Overall, this study provides new insights into the fate of uranium during its delivery along the aquatic food chain and highlights the risks associated with consuming uranium–contaminated aquatic products.

Study on the Pyrolysis and Incineration of Lewisite by Thermodynamic Equilibrium Calculation

AbstractLewisite is a representative chemical warfare agent that contains arsenic. Thermal decomposition is an essential method for Lewisite destruction, and appropriate destruction conditions can enhance the environmental friendliness of this method by minimizing the hazards of destruction products. In this study, the variation of Lewisite during pyrolysis and incineration was calculated, with particular emphasis on the evolution behaviors of arsenic and chloride with temperature, pressure, and molar ratio. The main products identified during pyrolysis were HCl(g), C, As, and AsCl3(g). Under anoxic conditions, AsCl3(g) and As were the dominant species. In oxygen‐enriched conditions, arsenic existed primarily as AsCl3(g), As2O5, As2O4, and AsOCl. Below 600 °C, arsenic predominantly existed in high valence forms such as As2O5. Above 600 °C, the binding capacity of chlorine and arsenic was stronger than that of oxygen, resulting in an AsCl3(g) molar fraction exceeding 75 % at 1200 °C. The primary chlorides in oxygen‐enriched conditions were Cl2(g), HCl(g), AsCl3(g), and Cl(g). Lower incineration temperatures (around 500 °C), sufficient oxygen conditions (molar ratio above 4 : 1), and positive pressures were conducive to reducing the toxicity of destruction products. The results are in good agreement with the experimental data.

Environmental behaviour of iron and steel slags in coastal settings

Iron and steel slags have a long history of both disposal and beneficial use in the coastal zone. Despite the large volumes of slag deposited, comprehensive assessments of potential risks associated with metal(loid) leaching from iron and steel by-products are rare for coastal systems. This study provides a national-scale overview of the 14 known slag deposits in the coastal environment of Great Britain (those within 100 m of the mean high-water mark), comprising geochemical characterisation and leaching test data (using both low and high ionic strength waters) to assess potential leaching risks. The seaward facing length of slag deposits totalled at least 76 km, and are predominantly composed of blast furnace (iron-making) slags from the early to mid-20th Century. Some of these form tidal barriers and formal coastal defence structures, but larger deposits are associated with historical coastal disposal in many former areas of iron and steel production, notably the Cumbrian coast of England. Slag deposits are dominated by melilite phases (e.g. gehlenite), with evidence of secondary mineral formation (e.g. gypsum, calcite) indicative of weathering. Leaching tests typically show lower element (e.g. Ba, V, Cr, Fe) release under seawater leaching scenarios compared to deionised water, largely ascribable to the pH buffering provided by the former. Only Mn and Mo showed elevated leaching concentrations in seawater treatments, though at modest levels (<3 mg/L and 0.01 mg/L, respectively). No significant leaching of potentially ecotoxic elements such as Cr and V (mean leachate concentrations <0.006 mg/L for both) were apparent in seawater, which micro-X-Ray Absorption Near Edge Structure (μXANES) analysis show are both present in slags in low valence (and low toxicity) forms. Although there may be physical hazards posed by extensive erosion of deposits in high-energy coastlines, the data suggest seawater leaching of coastal iron and steel slags in the UK is likely to pose minimal environmental risk.

Study of the Toxicity and Translocation of Chromium (VI) in Vicia faba Plant.

In soil, chromium can be found in two main valence forms: hexavalent Cr (VI) and trivalent Cr (III). In terms of toxicity, the most toxic form to plants is Cr (VI). In the present study, we investigated the impact of Cr (VI) (0, 25, 50, 75 and 100ppm) on growth, physiological parameters and the translocation kinetics of Cr (VI) in the faba bean plant (Vicia faba L.). The results showed that Cr (VI) negatively affects growth parameters (-15% to -72%), tolerance index (-34.05% to -64.7%), and reduce the total chlorophyll content (until 40%) compared to control plants without Cr (VI). However, the increase of Cr (VI) concentration in the soil, stimulated the synthesis of sugars (max 6,97mg/g FM), proteins (max 62.89µg/mg FM) and proline (max 98.57µg/mg FM) and increased the electrolyte leakage (+ 2.5% to + 9%) compared to control plants. Cr (VI) concentrations in shoots and roots increased significantly for all Cr (VI) doses applied. The translocation factor results showed that the majority of the Cr (VI) absorbed by the plant is stored in the roots, with a very low bioaccumulation factor, which does not exceed 0.4. The findings show that Cr (VI) negatively affects the morpho-physiological parameters of Vicia faba, the bioaccumulation of organic solutes and the low bioaccumulation factor of Cr (VI) can be considered as a strategy of tolerance to Cr(V).

The tendency towards equalization of the 234U/238U isotopic activity ratios in fractions of U(IV) and U(VI) during thermal annealing of metamict polycrase

The fate of the immobilized actinides of the spent nuclear fuel in mineral-like matrices can be predicted by studying the behavior of uranium isotopes as representatives of the actinides in natural analogues. This work deals with the thermochemical behavior of uranium isotopes, which is accompanied by a redox process within the 25–800 °C temperature range in the metamict natural analogue of polycrase. The pattern of the changes in the relative contents of the U(IV) and U(VI) fractions at various temperatures was determined by a radiochemical analysis. The accuracy of the U(IV) and U(VI) values using the method of the chemical shift of the energy on the Lα1 X-ray emission line was verified. The changes in the 234U/238U activity ratios of U(IV) and U(VI) fractions from room temperature to 800 °C revealed that 234U and 238U chose distinct thermochemical behaviors. It was discovered that 234U within the range from room temperature to 600 °C participated in redox processes to a greater proportion than 238U, and in the 700–800 °C temperature range, 238U participated in redox processes to a greater proportion than 234U. In the original polycrase, AR 234U(IV)/238U(IV) = 1.003 ± 0.010 and AR 234U(VI)/238U(VI) = 0.944 ± 0.005 were obtained. After heating the polycrase at 400 °C, AR 234U(IV)/238U(IV) value increased to 1.022 ± 0.010; AR 234U(VI)/238U(VI) value decreased to 0.928 ± 0.007. Currently, we do not understand where the different chemical behavior of the two isotopes of an element comes from. It is hardly surprising that at 800 °C, the values of AR (234U/238U) in both valence forms of U(IV) and U(VI) equalize and acquire the total initial value AR (Σ) = 0.963 ± 0.004. It is remains unclear to us at the moment what unknown laws and mechanisms these isotopes follow. The above uncertainties were not addressed in this work; it is hoped that mysteries of nature will be more explained in future research.

Highly efficient activation of periodate by a manganese-modified biochar to rapidly degrade methylene blue

In this study, the manganese oxide/biochar composites (Mn@BC) were synthesized from Phytolacca acinosa Roxb. The Mn@BC was analyzed via techniques of Fourier transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and X-ray diffraction analysis (XRD). The results show that MnOx is successfully loaded on the surface of BC, and the load of MnOx can increase the number of surface functional groups of BC. X-ray photoelectron spectroscopy (XPS) shows that MnOx loaded on BC mainly exists in three valence forms: Mn(Ⅱ), Mn(Ⅲ), and Mn(Ⅳ). The ability of Mn@BC to activate periodate (PI) was studied by simulating the degradation of methylene blue (MB) dye. The degradation experiment results showed that the MB removal rate by the Mn@BC/PI system reached 97.4% within 30 min. The quenching experiment and electron paramagnetic resonance (EPR) analysis confirmed that Mn@BC can activate PI to produce iodate (IO3•), singlet oxygen (1O2), and hydroxyl radical (•OH), which can degrade MB during the reaction. Response surface methodology (RSM) based on Box-Behnken Design (BBD) was used to determine the interaction between pH, Mn@BC and PI concentration in the Mn@BC/PI system, and the optimum technological parameters were determined. When pH = 5.4, Mn@BC concentration 0.56 mg/L, PI concentration 1.1 mmol/L, MB removal rate can reach 98.05%. The cyclic experiments show that Mn@BC can be reused. After four consecutive runs, the removal rate of MB by the Mn@BC/PI system is still 82%, and the Mn@BC/PI system also shows high performance in treating MB in actual water bodies and degrading other pollutants. This study provides a practical method for degrading dyes in natural sewage.

Electrochemical Behavior of Chromium Difluoride in Molten Lithium and Beryllium Fluoride Mixtures

The interaction between CrF2 and a molten binary LiF-BeF2 mixture has been studied using the electrochemical methods. The polarization of the chromium electrode relative to the dynamic beryllium electrode was measured. The obtained voltammetry data elucidates that under the experimental conditions, chromium is observed exclusively in one valence form. According to the cathode polarization dependences, it is established that the reduction of chromium ions in the metal occurs by a two-electron electrode reaction. The equilibrium concentrations of chromium were experimentally measured at the temperatures of 923, 973, and 1023 K at different chromium fluoride concentrations in the melt. The oxidation degree of chromium, dissolved in the melt, was calculated according to the concentration dependences of the equilibrium potentials. A thermodynamic analysis of the chromium difluoride dissolution in a molten mixture of lithium and beryllium fluorides was performed. The formation of dilute solutions of chromium difluoride is accompanied by slight deviations of the salt system from Raoult’s laws.

REVEALING AND DETERMINING THE FORMS OF COMPONENTS IN THE PRODUCT OF INTERACTION OF EUROPIUM (III) FLUORIDE WITH MELT OF NaCl-KCl

As part of the study of the solubility of lanthanide fluorides in salt melts, a study of the EuF3-NaCl-KCl system (upper and bottom parts) was carried out. This system is of particular interest due to the fact that Europium has two oxidation states (+2 and +3), and chloride ions are weak reducing agents. The studies were carried out by chemical and nondestructive spectroscopic methods. As for the latter, solid-phase luminescence (SPL), diffusereflectance spectroscopy (DRS), and X‑ray diffraction phase analysis (XRD) were used. The total content of lanthanides in the upper and bottom parts of the samples was determined spectrophotometrically and complexonometrically, respectively, and the content of Eu2+ was determined spectrophotometrically by the weakening of the KMnO4 color using redox reactions between Eu2+–V(V) and V(IV) (the content is equivalent to Eu2+) – KMnO4. The system (upper part) LaF3-NaCl-KCl was also studied (for Lanthanum the only oxidation state is +3) for the comparison. It was shown that during the dissolution of Europium fluoride in the NaCl-KCl melt, a partial reduction of Eu3+ to Eu2+ occurs. The data of SFL, DRS and chemical analysis showed that Eu2+ is the dominant form of europium in the upper part of the sample, and the content of EuF2 found by the chemical method (2.54% wt.) is close to the sum of the contents of EuF3 and EuF2 found by quantitative XRD (2,5% wt.). At the same time, the data of chemical and X‑ray diffraction phase analysis agree satisfactorily for the LaF3-NaCl-KCl sample. It has been suggested that the EuF3 phase detected by XRD could appear because of the oxidation of europium during the storage of the sample, and, possibly, due to the effect of ionizing radiation on the system at measuring. It has been established by spectroscopic methods that both valence forms of Europium are present in the bottom part of the sample, and the chemical analysis data (namely, the found content of fluoride ions) indicate the presence of other (except of Europium fluorides) fluorine-containing phases in this part. To identify the anionic forms of Eu3+, we used the dependence of the position of the diffuse reflection bands in the DR spectra change of variousinorganic compounds of trivalent europium form the reduced electronic polarizability of the ligand anions. According to the position of the reflection bands in the spectrum of the studied sample, it was found that the dominant form of Eu(III) in the bottom part is EuOCl∙25EuF3. Thus, using a combination of various physical and chemical methods, the presence of different valence and anionic forms of Europium in the EuF3-NaCl-KCl sample was shown and the dominant forms of Eu were established in the upper and bottom parts of the studied system.

Circularly polarized luminescence of pinene-modified tetradentate platinum(II) enantiomers containing fused 5/6/6 metallocycles

In this study, a couple of tetradentate Pt(II) enantiomers ((−)-1 and (+)-1) and a couple of tetradentate Pt(IV) enantiomers ((−)-2 and (+)-2) containing fused 5/6/6 metallocycles have been synthesized by controlling reaction conditions. Two valence forms could transform into each other through mild chemical oxidants and reductants. Single-crystal X-ray diffraction confirms the structures of (−)-1 and (−)-2. The coordination sphere of the Pt(II) cation in (−)-1 displays a distorted square-planar geometry and a platinum centroid helix chirality. In contrast, the structure of (−)-2 reveals a distorted octahedral geometry. The solution and the solid of (−)-1 are highly luminescent. Complex (−)-1 shows a prominent aggregation-induced emission enhancement (AIEE) behavior in DMSO/water solution with emission quantum yield (Φem) up to 73.2%. Furthermore, highly phosphorescent Pt(II) enantiomers exhibit significant circularly polarized luminescence (CPL) with a dissymmetry factor (glum) of order 10−3 in CH2Cl2 solutions at room temperature. Symmetrically appreciable CPL signals are observed for the enantiomers (−)-1 and (+)-1.

Synthesis, characterization of one Cr (III) complex: An efficient chemosensor for Cr (III) ions and designing of a molecular logic gate

A simple spectrophotometric based method for the detection of both the trivalent and hexa valent forms of chromium using 3-amino-2-pyrazine carboxylic acid (APC) is reported. Using APC as a ligand with Cr(NO3)3.6H2O a new mononuclear complex has also been synthesized and systematically characterized by elemental analysis and IR studies. Single crystal X-ray diffraction analysis reveals octahedral-type geometry with N3O3 coordination environments from the ligand. The optical sensing properties of APC for metal ions were enlightened by UV-Vis study. This sensor displays high selectivity and sensitivity towards Cr3+ in methanol. Interestingly the ligand displayed enhancement due to chelation with Cr3+and quenching while interacting with Cr6+ ions. Complete opposite spectroscopic behavior helps us to identify the oxidation state of chromium.The logical response of the molecular AND gate is realized and as the APC can efficiently sense Cr3+ in solitary as well as crowded conditions, presence of M+n ions would not have any effect to the logic functioning of the molecular AND gate.

Pion electromagnetic form factor with Minkowskian dynamics

The pion electromagnetic form factor has been calculated for the first time from the solutions of the Bethe-Salpeter equation, obtained directly in Minkowski space by using the Nakanishi integral representation of the Bethe-Salpeter amplitude. The one-gluon exchange kernel contains as inputs the quark and gluon masses, as well as a scale parameter featuring the extended quark-gluon vertex. The range of variability of these parameters is suggested by lattice calculations. After presenting a very successful comparison with the existing data in the whole range of the momentum transfer, we show how inserting the light-front (LF) formalism in our approach allows to achieve further interesting results, like the evaluation of the LF valence form factor and a first investigation of the end-points effects.

Computational Study of the Donor-Acceptor Interactions Underlying the Variable Oxygen Probe.

The variable oxygen probe (VOP) is a crystallographic technique that has been used to explore the relative donor abilities of various filled orbitals ranging from vicinal lone pairs to polarized heteroatom-carbon bonds, remote π functionalities, and strained carbon-carbon (CC) bonds. In this study, the donor-acceptor interactions which underlie the VOP have been explored in the gas phase using density functional theory on the model systems 1-13 with natural bond orbital analysis of the various donor-acceptor interactions involving both neutral and charged σ* antibonding orbitals as the acceptor probes. Updated values for the VOP slopes of 1-13 were shown to relate qualitatively with the sum of all significant donor-acceptor interactions present in these derivatives. Application of the VOP to calculated structures of 1-13 with various -OR substituents revealed a similar relationship between the C-OR bond distance to pKa (ROH). However, the VOP slopes in the gas phase were significantly smaller in magnitude than those obtained from crystal structural data, likely due to the valence form (C+-OR) being disfavored in the former, highlighting the advantage of the VOP as an experimental technique to discriminate donor ability more effectively than calculated structures.

Impact of Mn addition on catalytic performance of Cu/SiBEA materials in total oxidation of aromatic volatile organic compounds

Dealuminated BEA zeolite (SiBEA) was chosen as a support of metal oxide(s) phase for catalytic combustion of volatile organic compounds (VOCs). Copper and/or manganese oxide(s) were deposited at various Cu/Mn molar ratios. Factors influencing the catalytic activity were found by chosen physicochemical methods, including XRD, XRF, low-temperature N2 adsorption, FT-IR, UV–Vis-DRS, STEM-EDX, XPS and H2-TPR. Depending on the chemical composition, CuO, (CuxMn3-x)1-δO4, Cu-doped Mn3O4 or Mn2O3 was formed as the dominant phase. The active phase particles were located mainly in the interparticle voids of the zeolite support. SiBEA gained Lewis acid sites after the introduction of the metal oxide phase, especially in the case of CuO deposition. The presence of copper in the catalytic system resulted in enhanced reducibility of the active phase, and in a consequence in high catalytic activity in the total oxidation of aromatic VOCs, which proceeds according to the Mars-van Krevelen mechanism. After the introduction of Mn, the co-existence of different valence forms was found due to the redox equilibrium: Cu2+ + Mn3+ = Cu+ + Mn4+. Definitely, the addition of Mn to Cu/SiBEA increased the number of available surface vacancies and had a beneficial effect on the catalytic performance.

Neptunium(V) Isothiocyanate Complexes with 4'-Aryl-Substituted 2,2':6',2″-Terpyridines and N,N-Dimethylacetamide as Molecular Ligands.

New complexes of neptunyl(V) isothiocyanate with 4'-aryl-substituted 2,2':6',2″-terpyridines (Terpy) and N,N-dimethylacetamide (DMA) were obtained: [(NpO2)(4'-Ph-Terpy)(DMA)(NCS)]·DMA, [(NpO2)(4'-(4-(CF3)C6H4)-Terpy)(DMA)(NCS)]·2H2O·DMA, [(NpO2)(4'-(3-BrC6H4)-Terpy)(DMA)(NCS)]·DMA, and [(NpO2)(4'-(2-(COOH)C6H4)-Terpy)(DMA)(NCS)]·DMA. The structures of the compounds were determined with X-ray diffraction analysis. The neptunium coordination polyhedra were found to be pentagonal bipyramids with O atoms of the NpO2 groups in the apical positions and the equatorial planes formed by three N atoms of the terpyridine ligand, a N atom of the isothiocyanate anion, and an O atom of DMA. The influence of the substituents of the Ar group on the crystal structure is discussed. The IR spectra contain well-resolved bands of characteristic vibrations of all groups in the complex. The electronic absorption spectra are typical for neptunium(V) complexes and contain an intense narrow absorption band belonging to an f-f transition with a maximum of 988 nm and several long-wave satellites of lower intensity. The substituted terpyridines were shown to be efficient for the extraction of various valence forms of neptunium from the isothiocyanate solutions.

Influence of technological parameters on the vanadium valence form in slags

The multivalence of vanadium in oxide melts is considered. It is shown that the vanadium oxidation state in the slags is determined by the slag and metal compositions as well as the oxidation potential of the gas phase. Using a polymer model, vanadium valence form fractions were calculated depending on technological parameters. Calculations show that in an air atmosphere, vanadium in the slag should be predominantly in the tetravalent and trivalent state, and in contact with the molten iron, mainly in the trivalent and partly divalent state. Upon contact with pig iron, VO oxide becomes the main form of vanadium in the slag. Slag basicity and temperature have a significant effect on the relationship of vanadium forms. The suggested design-basis using the polymer model can be useful in accomplishment of the thermodynamic calculations for the vanadium equilibrium distribution between metal and slag in the iron and steel production. It allows us to describe the dependence of the vanadium oxidation state on the free oxygen activity in the slag and the gas phase oxidation potential.

Object-Oriented Diaspora Sensibilities, Disidentification, and Ghostly Performance

Object-Oriented Diaspora Sensibilities, Disidentification, and Ghostly Performance

The content of essential and toxic microelements in the organs of mice of various lines receiving a high-carb high-fat diet and supplemented with quercetin

Quercetin (Q) is known to be a powerful chelating agent for metal ions. Due to this property, Q, when ingested, is able to intervene actively in microelement homeostasis. The assessment of the possible significance of these effects for the dietary use of Q in obesity is complicated by the fact that in obese patients there are numerous changes in mineral metabolism and microelement homeostasis due to the pathogenesis of the disease. Thus, it is of considerable interest to identify the systemic effects of biologically active substances, including Q, on mineral metabolism in biological in vivo models (due to the limited choice of biosubstrates in clinical observations - blood plasma, urine, hair). The aim was to study the possible effects of Q on the levels of essential, non-essential and toxic elements in mice of three lines: db/db with knockout of the leptin receptor gene, prone to spontaneous development of obesity, inbred line C57Bl/6J, relatively resistant to the development of nutritional obesity, and complex hybrid of the 2nd generation DBCB, genetically more prone to developing obesity and fatty hepatosis when consuming diets with an excess quota of fat and simple carbohydrates. Material and methods. The content of 16 chemical elements (Fe, Mg, Cu, Mn, Co, Se, Zn, Cr, Al, Cd, As, Pb, Ni, Ag, V, Cs) was determined by mass spectrometry with inductively coupled plasma in the liver, kidneys, brain of genetically obese db/db mice (8-10 weeks old) receiving standard semisynthetic ration (SSD) and Q for 47 days at doses of 25 and 100 mg/kg body weight, C57Bl/6J mice treated with SPR or a high-fat high-carb diet (HFCD - 30% fats and 20% fructose solution instead of water) and Q supplementation at the same doses, DBCB tetrahybrid mice treated with SSD, HFCD and HFCD supplemented with Q for 63 days (25 mg/kg body weight). The compounds of Fe, Zn, Cu, Mn, Mg, Cr, Ni, Se, and V were included in the salt mixture in the form of inorganic salts or oxides in amounts close to physiological needs; Al, Cd, As, Pb, Ag, Cs, Co - were present in the diets in background amounts. Results and discussion. In db/db mice, in comparison with C57Bl/6J, a decreased content of Pb in the liver and increased in the kidneys and brain, decreased Co in the kidneys, increased Cs and As in the brain, which could not be explained by differences in the consumption of these elements with feed. The consumption of Q decreased the content of Mn, Cs, V, Ni, As in the liver in db/db mice and increased Cu and did not significantly affect the level of trace elements in the liver in animals C57Bl/6J. In kidneys of C57Bl/ 6J receiving Q, the content of As and Al increased. In brain of db/db mice, Q supplementation caused a decrease in the content of As, Pb, Cs and Se. In tetrahybrids DBCB, Q increased Pb levels in liver and brain and decreased in kidneys; increased the level of V in liver and brain; decreased As content in kidneys and increased in liver. Multiple correlations were noted between the organ content of elements in various valence forms, as well as between the content of trace elements and biochemical indicators of the intensity of catabolic and anabolic processes. Conclusion. Quercetin has an effect on the homeostasis of microelements, depending both on the animal genotype and on the diet, and not having unambiguous physiological significance. Indicators of the status of essential and toxic trace elements are recommended to be included in the protocols of preclinical trials of the efficacy and safety of minor biologically active food substances.