Hydrazine Sulfate Research Articles

Bismuth-coated screen-printed carbon electrodes for quantitative voltammetric determination of formaldehyde in urotropin

For the first time, a bismuth-modified electrode is used for the quantitative voltammetric determination of formaldehyde (FA) in urotropin. The well-established method of forming formaldehyde hydrazone (FAH) in the presence of hydrazine sulphate (HRZ) was employed to transform the hydrated form of FA into its electrochemically active derivative. The reduction current of FAH was recorded in a phosphate buffer solution (PBS, pH 5.2±0.1) in the presence of 0.09 M HRZ on a screen-printed carbon electrode that had been preliminarily modified with a bismuth film. A 20-second electrolysis at an applied potential of –0.28 V in a solution comprising 1 M HCl, 0.5 M NaBr, and 4 g/L Bi(III) resulted in the formation of a well-developed metal layer with an active surface. The determination of FA in technical urotropin yielded satisfactory results, indicating the potential for further applications of Bi/SPCE in pharmaceutical analysis.

Comparative study of Ni nanoparticles synthetized using electroless Ni plating waste and an analytical Ni reagent. Characterization and possible application in magnetic fluids

Wastewater from the electroless industry represents a potential danger to the environment and health, mainly due to its heavy metal content. In this study, nickel nanoparticles were synthesized through chemical reduction precipitation by using an electroless nickel plating waste and hydrazine sulfate as reducing agent. The aim of the present work is twofold. First we want to extract the metal from the aqueous medium, minimizing its content to levels allowed by environmental regulations. Second, we aim to valorize the residue by recovering the precipitated nickel to be applied as a solid phase in a magnetic fluid (MF). It is found that the present synthesis method using N2H4 as reducing agent, allowed us to minimize the Ni concentration in the aqueous waste in 97.49 %. The properties of the recovered Ni precipitate is compared with the Ni nanoparticles (NPs) obtained from a solution prepared with analytical grade nickel sulfate. The synthesized materials from both the waste (Ni-R) and analytical reagent (Ni-A) were characterized by comparing their chemical, physical, and morphological properties. In both cases, the Ni-R and Ni-A precipitates, spherical Ni NPs of 8–10 nm crystallite sizes are obtained, agglomerated in a bimodal size distribution centered at 174.6 and 383.4 nm, and a monomodal size distribution centered at 63.6 nm, respectively. Both Ni precipitated samples are ferromagnetic, but the Ni-R sample has a higher magnetic saturation of 40 emu/g compared to 8 emu/g of the Ni-A sample. The difference in the rheological behavior of both precipitates could be attributed to the presence of surface oxidation having a relatively less contribution in the case of the Ni-R particles due to the higher average size of the particles. The Fe content, probably coming from the nickel-plated parts in spent baths, is slightly higher in the Ni-R sample. Thus, the present work shows that it is possible to valorize an industrial Ni-based residue, by obtaining Ni precipitates that in magnetic fluids give even better results than those expected under more rigorous experimental conditions, i.e., in cases where the quality of the chemical precursors is usually a determining factor.

Unprecedented one-pot synthesis of 3,4-dihydropyrimidine-2-(1h)-ones catalyzed by hydrazine sulfate through Biginelli reaction, ADMET property, molecular docking studies and their antibacterial activity on Bacillus brevis and E. coli

The syntheses of 3,4-dihydropyrimidin-2(1H)-ones by one-pot, three-component condensation of aldehydes, β-ketoesters and urea or thiourea have been made more simple and efficient by using 20 mol% hydrazine sulfate as catalyst. Aldehydes, β-ketoesters and urea are cyclocondensed in the presence of hydrazine sulfate to produce dihydropyrimidines in ethanol under reflux conditions. The advantages of using hydrazine sulfate as a catalyst over the traditional Biginelli reaction conditions include outstanding yields (80–91%) and a shorter (10–15 hours) reaction time. In order to evaluate the antibacterial efficiencies of the synthesized compounds, we have studied the inhibitions of microbial proliferation of both Gram-positive (Bacillus brevis) and Gram-negative (E. coli) bacterial strains in comparison to a control group. The microbial inhibitions occur in the range of 40–98% by different derivatives of dihydropyrimidinones. Molecular docking studies of the synthesized compounds have also been done using software tools such as SwissADME.

A comparative study of discharging and leaching of spent lithium-ion battery recycling

Accelerated production of lithium-ion batteries (LIBs) implies an increase in the raw materials demand, especially for metals like lithium, cobalt, and nickel. Spent LIBs recycling guarantees the regeneration and reincorporation of valuable materials into the manufacturing industry; therefore, recycling methods and techniques must be optimized. In this investigation, alkaline and reductive acid leaching processes were evaluated and compared in order to determine the effect of parameters such as pH, temperature, and reagents concentrations to achieve selective leaching processes. This study demonstrated that strongly alkaline solutions (NaOH) do not ensure selective lithium and aluminum dissolution. Also, a solid compound, LiAl2(OH)6OH(s) can be formed at pH ∼14, negatively affecting the lithium extraction. On the other hand, reductive acid leaching, with acid sulfuric and hydrazine sulfate (H2SO4 + N2H6SO4) solutions resulted in an efficient system, extracting ≥90 % of Ni, Co, and Mn at 40 °C. Hydrazine is essential as a reductant, although it must be added in excess (40 % excess with respect to the Co, Ni, and Mn content) to suppress copper dissolution. Furthermore, this work demonstrated the possibility of processing the entire spent LIBs sample once the discharge and crushing stages were concluded, avoiding physical separation, without affecting the leaching efficiency and contributing to process economy.

Synthesis of novel polyethyleneimine-capped silver nanoclusters exhibiting ultraviolet-A fluorescence and their application in multiple sensing.

Cupric ions (Cu2+), pyrophosphate (PPi), and alkaline phosphatase (ALP) are involved in a variety of biochemical processes such as DNA replication, cellular metabolism and play an important role in human growth and development. It is of great significance to establish a method for the sensitive detection of Cu2+, PPi and ALP. In this work, polyethyleneimine-capped silver nanoclusters (PEI-AgNCs) were successfully synthesized by a one-pot method using hydrazine sulfate as reductant, exhibiting a unique strong fluorescence emission in the near-ultraviolet region at ∼339nm. Since the fluorescence of PEI-AgNCs can be quenched by Cu2+ through inner filtering effect (IFE), then recovered by competitive binding of pyrophosphate and Cu2+, and later weakened again by catalytic hydrolysis of alkaline phosphatase, a sensitive and selective strategy based on the changes of fluorescence "ON" or "OFF" was established to detect Cu2+, PPi and ALP. The LODs of these three analyteswere 36nM, 0.2μM, and 0.14 U L-1 at a S/N ratio of 3, respectively. A series of logic gate circuits for sensing cupric ions, pyrophosphate, and alkaline phosphatase were successfully constructed. The established methods have the potential for biosensing and environmental analysis and the specific UV-A fluorescence property of PEI-AgNCs may be helpful in photonic and optical areas.

Phosphorus Analysis in Meat using UV-Vis Spectrophotometry with SnCl2 and Hydrazine Sulfate Reduction

<p>This study aimed to optimize phosphorus analysis in meat using a molybdenum blue reaction involving SnCl<sub>2</sub> and hydrazine sulfate as reducing agents to establish the most effective conditions for phosphorus detection. Meat, an essential source of nutrients like phosphorus, plays a vital role in human health, particularly bone and tooth strength. However, overconsumption of phosphorus can lead to health issues such as hyperphosphatemia, making regular monitoring of phosphorus levels in food necessary. The experiment used SnCl<sub>2</sub> and hydrazine sulfate under varying acidic conditions to produce a stable blue complex indicative of phosphorus presence. The complex exhibited maximum absorbance in the 689–729 nm wavelength range. Validation of the method showed high linearity with R<sup>2</sup> values of 0.9983 and 0.9984 for SnCl<sub>2</sub> and hydrazine sulfate, respectively. The molar absorptivity for SnCl<sub>2</sub> was 2.093 x 105 L mol<sup>-1</sup> cm<sup>-1</sup> and 7.92 x 104 L mol<sup>-1</sup> cm<sup>-1</sup> for hydrazine sulfate. Detection and quantification limits were established, and the %RSD values in each sample ranged from 1.08% to 1.93%, conforming to standard requirements. Upon analysis of meat samples, including duck, chicken, and beef, the phosphorus levels did not meet the Indonesian Nutritionist Association (PERSAGI) standards. This result emphasizes the need for regular phosphorus analysis in meat products to prevent health risks associated with excessive phosphorus intake, such as hyperphosphatemia.</p>

Crystallization of isoniazid in choline-based ionic liquids: Physicochemical properties and anti-tuberculosis activity

Isoniazid is a drug commonly employed in the treatment of tuberculosis. One major barrier to its widespread use is that it can undergo hydrolysis when stored inadequately, resulting in the formation of hydrazine, a toxic and carcinogenic compound. Therefore, there is a clear need for further research aimed at improving the stability of isoniazid while still maintaining its therapeutic efficiency and solubility. To this end, five choline ionic liquids (ILs) were used for synthesizing improved forms of isoniazid: (2-hydroxyethyl)-trimethylammonium hydroxide [ChOH], (2-hydroxyethyl)-trimethylammonium hydrogen sulfate [ChBis], (2-hydroxyethyl)-trimethylammonium acetate [ChAc], (2-hydroxyethyl)-trimethylammonium citrate [ChCit], and (2-hydroxyethyl)-trimethylammonium benzoate [ChBenz]. The INH:[ChOH] and INH:[ChCit] forms were obtained in powder form, and presented low solubility and a minimum inhibitory concentration for Mycobacterium tuberculosis of 100 μg/mL and 12.5 μg/mL, respectively. The INH:[ChBenz], INH:[ChBis], and INH:[ChAc] forms showed a minimum inhibitory concentration value lower than 6.2 µg/mL. In the process using [ChBis], 2-(4-pyridiniumcarbonyl)-hydrazine sulfate with a water solubility of 155.9 mg/mL at 25 °C was produced, which showed to be more soluble than isoniazid (137.9 mg/mL). Therefore, the IL used had a direct influence on the solubility, conformational structure, and stability of isoniazid. This research is highly relevant and innovative for the use of new solvents in the crystallization of drugs, especially when aiming at the improvement of their properties.

A New Fe2O3-Graphene-Hydrazine Sulphate Nanocomposite as Anode Material with Enhanced Electrocatalytic Activity in an H2O2 Fuel Cell

In the present study, synthesis of various phases of iron oxide was carried out by simple combustion method. The synthesized iron oxides and their composites with graphene and hydrazine sulphate are investigated as electrocatalytic materials for hydrogen peroxide (H2O2) fuel cells. The activity was seen to be dependent on the phase composition, surface features and electrical properties which was altered due to the use of the different amount of oxalic acid as one of the precursors during the synthesis. The catalysts which are more active for decomposition of hydrogen peroxide, showed lower electrocatalytic activity. A significantly improved electrocatalytic performance is obtained when a nanocomposite electrocatalyst is prepared using iron oxide, graphene and hydrazine sulphate.

Study in the synthesis and crystal structure of the potentially genotoxic impurity E of Avanafil

In the classical route of synthesizing of avanafil, the last step of the reaction uses EDCI and HOBT as an acid and amine binding agent. HOBT may contain residues of hydrazine, and potential mutagenic impurities containing acylhydrazide structures may be formed. The intermediate product (M6) of avanafil was synthesized by 6 steps using diethyl ethoxylmethylmalonate and S-methyl isothiourea semisulfide as starting materials. The potentially genotoxic impurity E (Imp-E) of avanafil was given by the reaction of M6 and hydrazine sulfate acid amine, yield of 20%. The single crystal of Imp-E was cultivated by solvent volatilization method, and its structure was analyzed by high resolution mass spectrometry (HRMS) and nuclear magnetic resonance spectroscopy (NMR). The Flack parameter of Imp-E was -0.03(3) by X-ray single crystal diffraction analysis, and the absolute configuration of Imp-E was determined as S configuration. The intramolecular / intermolecular hydrogen bonds of Imp-E make the molecules maintain a stable arrangement in space.

Component Distribution Regulation in Sn-Pb Perovskite Solar Cells through Selective Molecular Interaction.

Tin-lead (Sn-Pb) perovskite solar cells (PSCs) with near-ideal bandgap still lag behind the pure lead PSCs. Disordered heterojunctions caused by inhomogeneous Sn/Pb ratio in the binary perovskite film induce large recombination loss. Here, an Sn-Pb perovskite film is reported with homogeneous component and energy distribution by introducing hydrazine sulfate (HS) in Sn perovskite precursor. HS can form hydrogen bond network and coordinate with FASnI3 thus no longer bond with Pb2+ , which reduces the crystallization rate of tin perovskite to the level of lead analog. The strong bonding between SO4 2- and Sn2+ can also suppress its oxidation. As a result, the Sn-Pb PSCs with HS exhibit a significantly improved VOC of 0.91 V along with a high efficiency of 23.17%. Meanwhile, the hydrogen bond interaction network, strong bonding between Sn2+ and sulfate ion also improve the thermal, storage, and air stability of resulting devices.

Transport of Chromium(VI) across a Supported Liquid Membrane Containing Cyanex 921 or Cyanex 923 Dissolved in Solvesso 100 as Carrier Phase: Estimation of Diffusional Parameters.

An investigation of chromium(VI) transport across a supported liquid membrane containing the phosphine oxides Cyanex 921 and Cyanex 923 dissolved in Solvesso 100 as carrier phases was carried out in batch operation mode. Chromium(VI) transport was investigated as a function of different variables: hydrodynamic conditions in the feed (1000-1600 min-1) and stripping (600-1500 min-1) phases, HCl (0.25-2 M) and indium (0.01-0.1 g/L) concentrations in the feed phase, and carrier (0.01 M-0.75 M) concentration in the membrane phase. Indium was recovered in the stripping phase using hydrazine sulphate solutions, and, at the same time, chromium(VI) was reduced to the less harmful Cr(III) oxidation state. Models describing the transport mechanism comprising a diffusion process through the feed aqueous diffusion layer, fast interfacial chemical reaction, and diffusion of the respective chromium(VI)-phosphine oxide complexes across the membrane were developed. The equations describing the rate of transport correlate the membrane permeability coefficient with diffusion and equilibrium parameters, as well as the chemical compositions of the respective metal-carrier phases. The models were used to calculate diffusional parameters for each metal-carrier system, and the minimum thickness of the feed boundary layer was calculated as 1 × 10-3 cm and 6.3 × 10-4 cm for the Cr(VI)-Cyanex 921 and Cr(VI)-Cyanex 923 systems, respectively.

Chemical modification of microcrystalline cellulose with polyethyleneimine and hydrazine: Characterization and evaluation of its adsorption power toward anionic dyes

Functionalization and various applications of biomaterials have progressively gained a major interest due to the cost-effectiveness, renewability, and biodegradability of these substrates. The current work focalized on the functionalization of microcrystalline cellulose with polyethyleneimine solution (3 %, 5 %, and 10 %) and hydrazine sulfate salt (1:1, 1:2, 2:1) using an impregnation method. Untreated and treated samples were characterized using FT-IR, SEM, XRD, TGA, and DTA analyses. The crystallinity index values for control microcrystalline cellulose, cellulose-polyethyleneimine, and cellulose-hydrazine were 57.13.8 %, 57.29 %, and 52.62 %, respectively. Cellulose-polyethyleneimine (5 %) and cellulose-hydrazine (1:1) displayed the highest adsorption capacities for calmagite (an anionic dye). At equilibrium, the maximum adsorption capacities for calmagite achieved 104 mg/g for cellulose-polyethyleneimine (5 %), 45 mg/g for cellulose-hydrazine (1:1), and only 12.4 mg/g for untreated cellulose. Adsorption kinetics complied well with the pseudo-second-order kinetic model. The adsorption isotherm fitted well with the Langmuir isotherm. Overall, the functionalized cellulosic samples could be considered potential materials for the treatment of contaminated waters.

Ultrasonic enhanced hydrazine sulfate acid leaching of low-grade germanium dust

By studying the principle of ultrasonic-enhanced leaching and the mechanism of reductive acid leaching of valuable metals, a new method of ultrasonic-enhanced hydrazine sulfate leaching of Zn and Ge in zinc oxide dust in the sulfuric acid system has been proved to be very effective. The phase of Ge was determined by the segmented dissolution method, and it was found that insoluble Ge mainly existed in the form of GeS2 and tetragonal phase germanium dioxide. Comparing the solubility of GeS2 and GeS in a hot high-acid system, it was found that GeS was more easily dissolved. And Ge4+ is more prone to hydrolysis at high acid concentration, resulting in germanium precipitation again. In addition, the presence of more Fe3+ in the solution will increase the potential of the system and inhibit the leaching of zinc ferrate. Therefore, the reduction method is used to reduce Ge4+ and Fe3+ to Ge2+ and Fe2+, which can accelerate the dissolution of zinc ferrate and effectively avoid the low leaching rate of zinc and germanium caused by the hydrolytic precipitation of Fe3+ and Ge4+. The valence states of Fe and Ge in the leachate were analyzed by ICP and XPS, and it was found that they mainly existed in the leachate in the divalent form, which indicated that Fe3+ and Ge4+ had been successfully reduced to Fe2+ and Ge2+. Some black substances were formed in the leaching process. EPMA analysis showed that the material was the oxide of silicon and aluminum, and the number of black substances increased gradually with the passage of leaching time, which led to the decreased metal leaching rate. The leaching kinetics is used to study the mechanism of the leaching process. By comparing the fitting degree of multiple models, the final mixed controlled model is determined to control the whole leaching reaction. Therefore, it is finally determined that when the initial acidity of 140 g/L, the liquid–solid ratio of 7 mL/g, the dosage of the reducing agent is 1/3 of the molar mass of Fe in zinc oxide dust, and ultrasonic intensity of 300 W is used to leach for 60 min at 333 K, Zn and Ge have the best leaching efficiency and economic benefits, and the leaching rates are 96.56 % and 94.62 %, respectively. Compared with conventional leaching, the leaching rate of Zn is increased by 6 %, and that of Ge is increased by 11 %.

Kinetic and Catalytic Study on a Hydrazine Sulphate Induced Fine Particle Sulphated Titanium(IV) Oxide with High Catalytic Activity towards Esterification Reaction

Kinetic and Catalytic Study on a Hydrazine Sulphate Induced Fine Particle Sulphated Titanium(IV) Oxide with High Catalytic Activity towards Esterification Reaction

Peculiarities of suction, extraction and assignment of calcium in experimental chronic hepatitis in rats

The aim. Study the degree of absorption, assimilation, and excretion of calcium in rats with chronic toxic hepatitis.
 Materials and methods. The studies were carried out on 1 month old Wistar rats. Toxic hepatitis in the experimental group was reproduced by intraperitoneal injection of hydrazine sulfate at a dose of 50 mg / kg twice a week. Studies of the absorption of substances in rats were carried out under thiopental anesthesia according to the Tyri method after 3 months of pathology modelling. In the intestinal contents, the amount of unabsorbed calcium and amino acids was determined. To determine the amount of assimilated and excreted calcium metabolic chambers were used for daily collection of urine, faeces and food residues, in which the calcium content was determined (average for three days per animal). After removing the rats from the experiment, the level of calcium in the blood serum was determined, in the bone tissue – the degree of its resorption by the activity of acid phosphatase and the content of calcium.
 Results and discussion. Toxic hepatitis reduced calcium absorption by 34.5 % in the small intestine of rats and did not have a significant effect on amino acids, the inhibition of absorption of which in hepatitis was only 5.5 %. The excretion of calcium in the urine of rats with toxic hepatitis was reduced by 1.8 times, and with faeces, on the contrary, increased by 1.5 times. As a result, calcium absorption in rats with hepatitis decreased by 24.2 %. Decreased absorption of calcium, and its increased excretion in the faeces, led to a decrease in the level of this element in the blood of animals with hepatitis by 14.7 %. Our studies found bone destruction in rats with hepatitis: an increase in bone acid phosphatase activity by 65.3 % and a decrease in calcium levels by 15.5 %.
 Conclusion. The triggering mechanism for the development of hepatic osteodystrophy is the inhibition of calcium absorption in the small intestine of rats with hepatitis, consequently - a decrease in its absorption and level in the blood, which ultimately leads to the activation of bone resorption. The established patterns will form the basis of the pathogenetic scheme for the prevention of hepatic osteodystrophy

Ultraviolet resistance modification of poly(1,3,4‐oxadiazole) fibers by dihydroxyterephthalic acid

AbstractDihydroxyl poly(1,3,4‐oxadiazole) (DHPOD) polymers are synthesized by copolymerization of 2,5‐dihydroxyterephthalic acid (2,5‐DHTA) and terephthalic acid with hydrazine sulfate in oleum, and then DHPOD fibers are prepared by wet‐spinning. The effects of UV irradiation on POD fibers' mechanical properties and surface morphology with and without hydroxyl groups were investigated. As proved by tensile testing and scanning electron microscope measurement, the UV resistance of DHPOD fibers is improved compared to that of p‐POD fibers. Besides, the heat resistance of POD fibers is not damaged by the introduction of phenolic hydroxyl groups. The UV and fluorescence spectra are used to analyze the UV resistance mechanism of the POD containing phenolic hydroxyl groups. Results show that the UV resistance mechanism of DHPOD is related to the proton transfer reaction between the 1,3,4‐oxadiazole ring and ortho phenolic hydroxyl group.

Synthesis and spectroscopic characterizations of manganese(II), iron(III), copper(II) and zinc(II) hydrazine complexes as catalytic activity agents

ABSTRACT. This article deals with the preparation and coordination of NH2—NH2 hydrazine molecule compounds. The hydrazine sulfate complexes of Mn(II), Fe(III), Cu(II), and Zn(II) were prepared. These complexes were characterized by elemental, infrared, conduction, electron absorption spectroscopy, magnetic susceptibility, thermogravimetric analyses, X-ray powder diffraction (XRD) patterns and atomic force microscopy (AFM) studies. The magnetic measurements were confirmed that the Mn(II), Fe(III), Cu(II), and Zn(II) hydrazine complexes have an octahedral geometric structure. Thermogravimetric and its differential thermogravimetric analysis referred that all complexes passed through two-to-three thermal degradation steps with solid metal sulfate as a residual product. The infrared spectra inferred that the NH2—NH2 ligand forms complexes through nitrogen atoms of the—NH2 moiety, while the elemental analysis indicates [M(NH2—NH2)3]SO4 (where M = Mn(II), Cu(II), and Zn(II)) while the iron(III) complexes have the [Fe2(NH2—NH2)4(SO4)2]SO4 formula of coordination compounds, NH2—NH2 acts as a double bond. Both XRD and AFM analysis deduced that the synthesized hydrazine metal complexes were found to be in nano scale range 10—30 nm.
 
 KEY WORDS: Hydrazine, FTIR, AFM, XRD, Transition metals
 Bull. Chem. Soc. Ethiop. 2022, 36(1), 33-44. 
 DOI: https://dx.doi.org/10.4314/bcse.v36i1.4

Bismuth-coated screen-printed electrodes for the simple voltammetric determination of formaldehyde.

For the first time, bismuth modified electrodes have been used for the voltammetric detection of formaldehyde (FM). The well-known method of forming formaldehyde hydrazone (FAH) in the presence of hydrazine sulphate was used to convert the hydrated form of FM into its electrochemically active derivative. Various experimental conditions for differential pulse voltammetry were studied to achieve the best analytical performance. The FAH reduction current (FM response) reaches its maximum value at a pH of a phosphate buffer solution of 5.2 ± 0.1 in the presence of 0.09-0.12 M hydrazine sulfate on a bismuth film preliminarily precipitated for 8-12 min from acidic Bi(III) acetate solutions at an electrolysis potential of -1.0 V on the surface of a screen-printed carbon electrode (SPCE). A dendritic-like film structure was created on the SPCE surface. Under the optimized conditions a linear calibration curve over the range of 0.01-5 mg L-1 (0.33-167 μM) FM was achieved, with a detection limit of 0.002 mg L-1 (0.06 μM). The determination of FM in waste water, melt water from snow within the city industrial zone, and a widely used pharmaceutical preparation "Endofalk®" with good results revealed the potential applicability of a bismuth modified SPCE (BiSPCE) for trace analysis.

ABSORPTION OF CALCIUM IN SMALL INTESTINE OF RATS AFTER IMPACT OF VARIOUS XENOBIOTICS

Relevance. Pathology of the thyroid and parathyroid glands, diseases of the digestive system, blood system, etc, as well as application of medications used for their treatment can result in the condition which is characterised by reduction of bone density – secondary osteoporosis. The aim of the research was to determine absorption of calcium in the small intestine of rats under impact of various xenobiotics. Materials and methods. The research was performed on white rats of herd breeding which, depending on the group obtained during 60 days: 1) cefoperazone (p/o, 180 mg/kg per day) and amoxiclav (p/o, 135 mg/kg per day); 2) mercazolil (p/o, 25 – 40 mg/kg per day); 3) L-thyroxine (p/o, 10 mg/kg per day); 4) hydrazine sulphate (50 mg/kg 2 times per week for 90 days). Calcium absorption was studied in an isolated loop of the small intestine of the animals. The condition of the small intestine mucous membrane was estimated in accordance with inflammation markers (elastate and acid phosphatase activity, index of the degree of opportunistic microbiota (urease activity), index of non-specific antimicrobial protection of mucous membranes (lysozyme activity). Long-term application of antibiotics contributed to reduction of calcium absorption in the small intestine of rats by 25.0 %, of mercazolil – by 29.7 %, of thyroxine – by 11.4 %, of hydrazine sulphate – by 34.5 %. The increase of elastase and acid phosphatase activity in the mucous membrane of the small intestine under the action of xenobiotics, as well as increase of urease activity and reduction of lysozyme activity testify to the change in the small intestine condition. Сonclusions. So, the significant reduction of calcium absorption after long-term application of xenobiotics can be first of all connected with inhibition of antimicrobial protection of the small intestine mucous membrane under the action of antibiotics, mercazolil, thyroxine and hydrazine sulphate. More active multiplication of opportunistic bacteria, presence of dysbiosis, and, after application of antibiotics and hydrazine sulphate, development of inflammation can be the consequence of lysozyme activity reduction.

Морфометричні та метаболічні порушення у кістковій тканині лабораторних щурів з хронічним токсичним гепатитом

The development of osteodystrophy in diseases of the hepatobiliary system is a known fact, but the mechanism of the formation of metabolic disorders in bone tissue in liver pathology is not fully understood. The purpose of the study was to study morphological and biochemical changes in the bone tissue of female and male rats during the modeling of chronic toxic hepatitis. Materials and methods. Modeling of toxic hepatitis was carried out on 1 month old male and female Wistar rats by intraperitoneal injection of hydrazine sulfate 50 mg / kg twice a week for 3 months. The experiment was conducted in accordance with the norms and principles of the EU Council Directive on the protection of vertebrates used for scientific purposes. Morphometric measurements (density, content of mineral-organic, mineral and organic components) were carried out on the femurs and the last lumbar vertebra. Elastase activity, acidic phosphatase (indicators of bone resorption); alkaline phosphatase activity and calcium content (indicators of the synthesis of new bone tissue) were determined in homogenates of the bone tissue of the jaws and femur. The mineralizing index was calculated from the ratio of the activities of acidic phosphatase and alkaline phosphatase. Results and discussion. A decrease in the quantities organic matrix with a preserved intensity savings of bone tissue mineral parts in females and a decrease intensity in bone tissue mineralization in males under the influence of toxic hepatitis were found. Biochemical studies of bone tissue showed the activation of the destruction of the protein matrix of the bone, the intensification of mineralization in females, as well as the activation of hydrolysis of hydroxyapatite, along with a decrease in the level of calcium in the bone tissue of animals of both sexes against the background of modeling of chronic toxic hepatitis. Conclusion. The studies carried out have established multidirectional disorders of the metabolism and structure of bone tissue in males and females, induced by prolonged administration of hydrazine sulfate: in females, suppression of the formation of an organic matrix with a preserved intensity of bone mineralization, and in males, a decrease in bone mineralization against the background of a slightly increased intensity of synthesis of the organic component. The established patterns made it possible to reduce the negative effect of Hydrazine Sulfate on the protein metabolism of rat bone tissue, indirectly through the metabolism of estrogens. The results of our study provided experimental justification for the development of a scheme for the Prevention of osteodystrophic conditions in conditions of chronic exposure to toxins or impaired liver function