Heavy Metal Salts Research Articles

Density of lymphocytes in cortex and medulla substance of thymus particles of white rats in normal conditions and under influence of heavy metal salts during three months

The consumption of clean water is the most relevant today, but natural water is delivered to our homes through plastic, iron and galvanized pipes. Metal ions, which are part of the pipe material, can get into drinking water and affect the human body, in particular the thymus. That is why the aim of the work was to determine the density of large, medium and small lymphocytes in the cortex and medulla of the thymus lobules of outbred white male rats of reproductive age when consuming small doses of heavy metal salts with water for three months. The study was conducted on 40 outbred white male rats of reproductive age, which were divided into 4 groups: 1 group – control animals that consumed distilled water; 2 group of animals that consumed aqueous solutions – CuSO4·5H2O at a dose of 0.247 mg/dm3; 3 group – aqueous solution of ZnSO4·7H2O at a dose of 1.505 mg/dm3; group 4 – aqueous solution of FeSO4·7H2O at a dose of 0.5 mg/dm3. Histological, electron microscopic and morphometric research methods were used to study the density of large, medium and small lymphocytes in different zones of the thymus lobules. It was found that in the control group of rats, the density of large lymphocytes is the highest in the subcapsular zone, and the lowest in the medulla. The density of medium lymphocytes is the lowest in the subcapsular zone. The density of small lymphocytes is the lowest in the medulla, and the highest in the cortico-medullary zone. When using CuSO4·5H2O salts with drinking water for three months, there were no significant changes in the density of lymphocytes compared to the control group, except for a slight decrease in the density of large lymphocytes in the cortex of the thymus lobules. The density of lymphocytes in the third group of animals that consumed zinc salts (ZnSO4·7H2O) with drinking water changes significantly: the density of large lymphocytes in the subcapsular zone decreases by 2.3 times, in the cortico-medullary zone it increases by 4.7 times, and in the medulla it increases by 2.7 times; the density of medium lymphocytes decreases in the subcapsular zone by 2 times; the density of small lymphocytes decreases by 1.5 times in the subcapsular zone, in the cortex and cortico-medullary zone – decreases by 1.2 times, and in the medulla by 1.1 times. When using FeSO4·7H2O salts with drinking water for three months, no special changes in the density of lymphocytes were noted: a decrease in the density of large lymphocytes in the subcapsular zone by 1.5 times and by 1.3 times in the cortex was observed; the density of medium lymphocytes decreases by 1.2 times in the cortex, and the density of small lymphocytes decreases by 1.2 times in the subcapsular zone and cortex, and increases by 1.2 times in the medulla, compared to the control group of animals. Ultrastructural changes in the structure of lymphocytes and reticuloepithelial cells were not detected when heavy metal salts were consumed with water. Thus, the study showed that the most toxic for the body are zinc salts (ZnSO4·7H2O), the consumption of which with drinking water in small doses for three months led to significant changes in the density of lymphocytes, compared to the control group experimental animals.

Exploring biosynthesis strategies to boost the yield of exopolysaccharide-protein blend from Bacillus arachidis SY8(T), an isolated native strain, as a potent adsorbent for heavy metals removal

This investigation centers on the synthesis of a polysaccharide-protein blend produced by an isolated native strain (99.12 % phylogenetic affinity with Bacillus arachidis SY8(T)). The primary objective was to investigate the production of extracellular polymeric substances (EPS) under diverse stress conditions, encompassing exposure to heavy metal ions, salt, and toxic agents. Additionally, the impact of environmental parameters, namely pH, inoculation percentage, and time, on the production was investigated. Subsequently, the study examined the biosorption potential of the EPS produced for Pb(II), Cu(II), and Mn(II). The EPS obtained was thoroughly characterized via various tests. Rheological evaluations of an EPS solution (2 wt%) confirmed its pseudo-plastic and non-Newtonian fluid properties, while TGA analysis demonstrated its thermal stability up to 600 °C. Additional analyses, including GPC, FTIR, and H-NMR, provide further insights into the produced EPS. The best conditions for EPS production are determined: 5 % NaCl salt, serving as an effective stress inducer, and 37 °C, pH 6, with a 5 % inoculation, over 96 h. EPS demonstrates remarkable removal efficiencies of 99.9, 99.4 and 78.9 % for Pb(II), Cu(II), and Mn(II), respectively. These findings highlight the potential of EPS as an effective agent for removing heavy metal ions.

RADIATION AND ECOLOGICAL STUDIES OF VEGETATION OF LUTSK DISTRICT OF VOLYN REGION

Abstract. The content of radionuclides of 137Сs, 90Sr and heavy metals in vegetation and agricultural products was found out in the settlements of Lutsk district of Volyn region. The results of our own field expeditionary research, as well as the results of generalization of stock materials of the Laboratory of Ecological Land Safety and Product Quality of the Volyn branch of the state institution “Institute for Soil Protection of Ukraine” (Lutsk) are the basis of the research. The plant products contain a small content of radioactive elements in the settlements of the Lutsk district of the Volyn region. The greatest pollution of plant products was found in the settlements of Sytnytsia and Omelіano. The content of the 137Сs, 90Sr does not exceed the maximum permissible concentrations. Exceeding the maximum permissible concentrations for the content of heavy metal salts was found in potatoes in the villages of Pozharky, Vesele. The results of the radiation-ecological study can be taken into account for the optimization of nature management and are necessary for state emergency management bodies of natural-technogenic content, for the possibility of reasonable planning and effective implementation of measures and projects for strengthening ecoenvironmental safety. The data obtained are important for the development of the National Concept to overcome the consequences of the Chernobyl disaster on the contamination of agricultural products with radionuclides and heavy metals.

An overview of heavy metals treatment & management for laboratory waste liquid (LWL)

The laboratory waste liquid (LWL) is the discarded liquid after the completion of analysis and is produced from the testing laboratories including regulatory institutions, colleges, universities and research organizations. This LWL is laden with a variety of heavy metals due to the use of heavy metal salts in analysis and the treatment and safe disposal of LWL is seldom given due consideration. Thus, the management of hazardous laboratory waste liquid (HLWL) containing heavy metals is essential at the source itself. Accordingly, this article presents systematic review of three processes for heavy metals removal viz. precipitation, adsorption, and membrane separation. The review covers various factors such as heavy metal removal efficiencies & concentration ranges, optimum pH, most frequently studied methods, less studied aspects, its commercial availability, operational ease, and the potential of risk minimization with due concern to toxic heavy metals. The concentrations of heavy metals in LWL is also presented. Based on the review, activated carbon (AC) adsorption appears to be the best option for LWL having heavy metals concentration of less than 10 mg/L. The heavy metals removal efficiency of more than 95% can be achieved at an AC dose of 0.2–1 g/L. The hydroxide precipitation was found to achieve more than 95% removal efficiencies at higher heavy metals concentrations. Thus, for concentrations higher than 10 mg/L up to 3000 mg/L, the hydroxide precipitation followed by activated carbon adsorption may prove beneficial.

Tea plantation shade tree leaf influences the susceptibility of rhizosphere microbial consortium: A comprehensive study on their leaf extract cross tolerance

Leguminous shade trees are ubiquitous parts of tea plantations of the Terai region. However, their shed leaves might have an effect on the soil microflora under those shade trees, so it is important to find out how leaf litter affect the soil microflora. Isolation of soil microbial consortia followed by downstream experiments were conducted to observe the tolerance/susceptible pattern of those soil microflora against the fallen leaves. Sample from under Albizia odoratissima has higher organic carbon, organic matter and nitrogen content but the same property was found to be low in the sample collected under Melia azedarach. Isolation of consortia was done on nutrient agar. In vitro tolerance assay was conducted to find out the tolerance pattern against leaf extracts, heavy metal salts, pesticides, antibiotics and antifungals. Heavy metals salts like Arsenic trioxide (AS2O3) and Cupric chloride (CuCl2); and pesticides like Thiamethoxam; Spiromesifen; Phorate etc. showed no inhibition against all the isolated consortia. Co-Trimoxazole and Augmentin have not showed any inhibition except consortia under Derris robusta, whereas no antifungals but Itraconazole had an impact over all the consortia. Shade trees, being a crucial member of the tea plantations, cannot be removed but replacement of these with other species could be a probable option, besides this limited use of chemical pesticides and fertilizers should be taken into consideration strictly to restrain the microbial population in tea garden soil. So, this study has disclosed the acceptability of each and every shade tree used in this region.

Aluminum and ABC transporter activity

Aluminum is the third most common element on Earth´s crust and despite its wide use in our workaday life it has been associated with several health risks after overexposure. In the present study the impact of aluminum salts upon ABC transporter activity was studied in the P-GP-expressing human blood-brain barrier cell line hCMEC/D3, in MDCKII cells overexpressing BCRP and MRP2, respectively, and in freshly isolated, functionally intact kidney tubules from Atlantic killifish (Fundulus heteroclitus), which express the analog ABC transporters, P-gp, Bcrp and Mrp2. In contrast to previous findings with heavy metals salts (cadmium(II) chloride or mercury(II) chloride), which have a strong inhibitory effect on ABC transporter activity, or zinc(II) chloride and sodium arsenite, which have a stimulatory effect upon ABC transport function, the results indicate no modulatory effect of aluminum salts on the efflux activity of the human ABC transporters P-GP, BCRP and MRP2 nor on the analog transporters P-gp, Bcrp and Mrp2.

Molecular identification and characterization of endophytic bacteria from root of chamaecrista rotundifolia growing on the nigerian air force shooting range, kaduna.

Chamaecrista rotundifolia is one of the few plant species growing on heavy metal-contaminated Nigerian Air Force shooting range, Kaduna. This microbially unexplored plant species can have microbial association with endophytes. This study was aimed at isolating, identifying and characterizing endophytic bacteria associated with the roots of Chamaecrista rotundifolia growing on the Nigerian Air Force shooting range, Kaduna. The identification of the endophytic bacteria was done using standard biochemical methods and 16S rRNA sequencing analysis. The isolates were then screened for antibiotic resistance, plant growth promoting properties and heavy metal tolerance using standard techniques. Varied concentrations of heavy metal salts (Pb2+, Cr3+, Ni2+ and Mn2+) were used to test the isolates for their heavy metal tolerance. Four endophytic bacteria isolated from the roots of C. rotundifolia were Aerococcus viridans, Peribacillus simplex, Staphylococcus simplex and Pseudomonas aeruginosa. Results on antibiotic sensitivity test revealed that the four isolates were resistant to most of the antibiotics. The isolates possessed plant growth promoting properties by showing positive results for Indole-3-acetic acid (IAA) production, 1-aminocyclopropane-1-carboxylic (ACC) deaminase activity and phosphate solubilizing. Results also revealed that the isolates showed some degree of tolerance to the heavy metals. The tolerance of both A. viridans and P. simplex to chromium and manganese showed significant difference (p<0.05) across all the concentration levels of the metal salts. It is therefore concluded that Chamaecrista rotundifolia growing on Nigerian Air Force shooting range, Kaduna, is associated with endophytic bacteria which could be the reason the plant species thrive in heavy metal-contaminated site.
 

Nanofiltration membrane with surface nanostructure induced by interfacial modification for heavy metal ions removal, salt selection and antibacterial

Positively charged nanofiltration membranes offer promising options for the removal of heavy metal ions. However, their electrical properties often lead to serious drawbacks such as impaired filtration performance and poor fouling resistance, thus further modification of these positively charged membranes are imperative. Herein, we report the interfacial manipulation of nanofiltration membranes using a hydroxyl monomer (β-cyclodextrin) in concert with the typical positively charged ammonia monomer (polyethyleneimine) to achieve efficient removal of heavy metals, improved perm-selectivity and fouling resistance. The results indicated that water flux of the modified membrane was increased by over 2-folds owing to structural modification compared with pristine membrane. The charge effects and enhanced cross-linking improve the rejection of salts ions, especially divalent ions. The topological and Turing-structured membranes reached 99.9% removal of heavy metal ions due to the combination of adsorption, complexation, Donnan and site resistance effects, and has excellent stability. Additionally, the functionalized membranes exhibited reduced adhesion and survival of bacteria on the surface based on the excellent bacteriostatic and hydrophilicity properties. These findings revealed the mechanism of interfacial modification induction on the nanostructure and properties of membranes and provided an efficient solution for the synthesis of multifunctional membranes.

CHEMICAL ELEMENTAL COMPOSITION OF DATURA STRAMONIUM L. GROWING IN UZBEKISTAN

Inductively coupled argon plasma mass spectrometry (ICP-MS) was used to study the elemental composition of the underground and aboveground parts of the Datura stramonium growing on the territory of the Republic of Uzbekistan. The obtained data show that 41 elements were found in the composition of the vegetative organs of the D. stramonium, including 6 macroelements (Ca, P, K, Na, S, Mg), 8 essential microelements (Co, Cr, Cu, Fe, Mn, Se, Zn, Mo), and 6 conditionally essential. Moreover, 6 trace elements (B, Si, Ni, V, As, Li), 16 toxic (Pb, Cd, Ge, Sr, Zr, Tl, Bi, Sn, Sb, W, Ag, Ba, Al, Ga, Ti, Be) and 5 little studied elements (Nb, Cs, Ta, Rb, Re) were identified. It was revealed that among the detected elements in D. stramonium, 3 macroelements (Ca, K and Fe) are contained in a concentration of more than 1000 mg/kg, 4 elements (P, S, Mg, Si) are from 100 to 1000 mg/kg, 3 elements (Na, Mn, B), ranging from 10 to 100 mg/kg and the rest were in the range of less than 10 mg/kg. The macroelements were located between each other in the following order: in the roots of the plant Ca (40%)>K (39%)>P (9%)>Mg (6%)>S (4%)>Na (2%), and in the aerial part of the plant Ca (50%)>K (30%)>Mg (9%)>P (7%)>S (3%)>Na (1%). The highest content of essential trace elements in the composition of the roots and aboveground parts of the D. stramonium falls on the share of Fe (n/h 2015.4521 mg/kg, n/h 1516.3041 mg/kg), and among the conditionally essential microelements Si (n/h 397.8607, n/ch 234.4246). It has been established that the higher content of toxic elements in the composition in the underground part of D. stramonium falls on the proportion of A1 (36.92%) and Ti (35.54%), and in the aboveground part of Ga (48.57%) and Al (17.37%), relative to the total content toxic elements. According to the content of salts of heavy metals of the D. stramonium growing in Uzbekistan meets the requirements established by the Global Fund XIV and WHO. Salts of toxic elements Hg were not found. Comparative data showed that in both organs of D. stramonium growing in Uzbekistan, the content of the considered elements is lower than amount of the element of D. stramonium growing in Kazakhstan and South Africa.

Plasmonic group 4 transition metal carbide interfaces for solar‐driven desalination

AbstractTo combat the dwindling supply of freshwater, solar‐driven desalination using plasmonic nanomaterials has emerged as a promising and renewable solution. Refractory plasmonic carbide nanomaterials are exciting candidates that are inexpensive and chemically robust but have not been widely explored. Herein, plasmonic carbide interfaces made of TiC, ZrC, and HfC nanoparticle aggregates loaded onto to a mixed cellulose ester (MCE) membrane were explored to gain insight into their solar‐vapor generation and desalination potential. Desalination using Atlantic Ocean water under 1 sun intensity yielded rates of 1.26 ± 0.01, 1.18 ± 0.02, and 1.40 ± 0.01 kg m−2 h−1, with efficiencies of 86%, 80%, and 96% for TiC, ZrC, and HfC, respectively. Carbide interfaces showed good stability and effectively removed heavy metal ions and salt from solutions with concentrations up to 35%. PVA hydrogel based TMC evaporators afforded rates of 3.31 ± 0.03 and 3.22 ± 0.03 kg m−2 h−1 for TiC and ZrC, respectively. The HfC‐PVA interface afforded a high solar desalination rate of 3.69 ± 0.04 kg m−2 h−1, corresponding to an efficiency of 97% under 1‐sun illumination. The hydrogel evaporators also retained their strong salt rejection action over time.

Phytoremediation Potential of Different Genotypes of Salix alba and S. viminalis.

Elevated concentrations of heavy metals result in soil degradation, a reduction in plant yields, and a lower quality of agricultural products, which directly endangers people, animals, and the ecosystem. The potential of three clones of Salix alba (347, NS 73/6, and B-44) and one genotype of S. viminalis for the phytoextraction of heavy metals was investigated, with the aim of identifying the most physiologically suitable willow genotypes for use in soil phytoremediation. The experiment was placed on the contaminated soil substrate collected in Kolubara Mining Basin (Serbia), enriched by high loads of heavy metal salts, and a control medium. Significant differences in the concentrations of heavy metals were recorded between the contaminated and control plant material, especially when it comes to nickel (Ni), copper (Cu), cadmium (Cd), and lead (Pb), confirming that S. alba and S. viminalis are hyperaccumulator species of heavy metals. Clone 347 shows the greatest uptake of Cd and chromium (Cr), and clone B-44 takes up these metals only to a lesser extent, while clone NS 73/6 shows a less pronounced uptake of Cr. The roots have the greatest ability to accumulate Ni and Pb, Cu is absorbed by all plant organs, while Cd is absorbed by the leaves. The organ that showed the greatest ability to accumulate heavy metals was the root, which means that willows have a limited power to translocate heavy metals to above-ground organs. The studied genotypes of S. alba have a higher potential for the phytostabilization of Cu and Cd, as well as the phytoextraction of Cd, compared with S. viminalis. The results confirm the assumption of differences between different willow genotypes in terms of the ability to phytoextract certain heavy metals from soil, which is important information when selecting genotypes for soil phytoremediation.

Exploring a sustainable binder for capacitive deionization technology to achieve high salt and zinc ion removal efficiency

As a newly developed water purification technology, capacitive deionization (CDI) is a promising technology for water desalination. The influence of binders on the performance of CDI electrodes, especially on the performance of heavy metal ion removal, has been rarely discussed so far. On the other hand, searching sustainable materials to replace those made from non-renewable resources is attracting more and more attention. Herein, the influence of the sustainable binders on CDI performance is studied. For the NaCl adsorption, the chlorinated rubber (CLR) electrode shows a higher capacity and rate capability than the other binders. Particularly, we explored the CDI process for zinc ion in water and claimed that the formation of hydroxide of zinc ion should be considered. Surprisingly, CLR can inhibit Zn4SO4(OH)6•5H2O generation and structural disruption of electrode. CLR electrode has the highest desalination performance, 79.8 mg g−1 of ZnSO4 and the longest cycle lifetime remaining 95.4 % of adsorption capacity after 10,000 cycles. Moreover, CLR can be made from sustainable natural rubber and its price is only 14.3 % of PVDF. Obviously, CLR is promising for heavy metal salt removal and large-scale water purification devices. CLR also shows superior performance than PVDF in aqueous zinc capacitor.

All-in-one chitosan-based aerogel with a semi-clad structure for solar-driven interfacial evaporation

Solar-driven interfacial water evaporation is a promising technique for recovering clean fresh water and alleviating water scarcity. In this work, an all-in-one chitosan-based composite aerogel with a highly porous semi-clad structure was fabricated. In the process of interfacial water evaporation, the hydrophilic outer layer of the aerogel efficiently transported water to the upper surface through two-dimensional transport channels. Simultaneously, it rapidly converted absorbed sunlight into heat, demonstrating excellent photothermal conversion capabilities for efficient water evaporation. The hydrophobic inner core enabled the aerogel to float stably on the water surface, and had a low thermal conductivity to reduce heat dissipation into the water body. Under 1 sun illumination (1 kW m−2), the composite aerogel showed an evaporation rate of up to 1.547 kg m−2 h−1, corresponding to an evaporation efficiency of 91.47 %. Notably, the composite aerogel demonstrated high stability and recyclability in desalination and heavy metal wastewater treatment, which had great potential in recovering both clean water and heavy metal salts. The evaporator with a semi-clad structure had practical applications in solar desalination and sewage treatment due to its stable and efficient evaporation performance and simple preparation method.

Safety control of meat and meat products

The country's food security is an important and, at the same time, difficult task for Russian agriculture in the context of the import substitution policy. Ensuring the safety and quality of raw materials and food products is a necessary condition that determines the health of the population and the preservation of its gene pool. The most crucial measure in solving the problem of the quality of livestock products is a scientifically based veterinary and sanitary assessment of meat and other livestock products. Therefore, control of the quality and safety of meat and its processed products is a relevant topic for study. The article analyses the procedure for the work of the regional veterinary service on the issues of monitoring the safety of meat and meat products and the data of the annual reports of the 5-vet test centre of the “Regional State Budgetary Institution (RSBI) "Altai Regional Veterinary Center for the Prevention and Diagnosis of Animal Diseases"' for 2020 - 2021. It has been established that the system of veterinary and sanitary control of the safety and quality of meat and meat products in the Altai Territory is carried out by the developed scheme and consists of tests of selected samples in testing laboratories accredited for these indicators. For the period 2021 – 2022 in the Altai Territory, no specimens with deviations from the regulatory documents TR CU 021/2011 Technical Regulations of the Customs Union “On the Safety of Food Products”, TR CU 034/2013 Technical Regulations of the Customs Union “On the Safety of Meat and Meat Products” were found in the tested samples. Tests are carried out quarterly for physical, chemical, and microbiological indicators of pesticides and annually for heavy metal salts, radionuclides, the presence of antibiotics, nitrites and hormones. The analysis results allow us to conclude the timely identification of meat and meat products of questionable quality.

Dynamics of changes in cadmium levels in environmental objects and its impact on the bio-elemental composition of living organisms.

As a result of intensive anthropogenic impact in the biosphere there is a rapid process of accumulation of heavy metal salts. They have led to the aggravation of problems associated with the pollution of ecosystems and basic food products of plant and animal origin. Environmental pollution by these compounds is caused by their persistence in environmental objects, migration ability, accumulation by plants. This contributes to their accumulation in the human environment. A number of studies have shown that heavy metals have mutagenic, toxic effects and affect the intensity of biochemical processes. Therefore, the presence of heavy metals in the environment is extremely undesirable. Moreover, the ecological state of the environment is directly related to changes in the human internal environment. Deficiency or excess of certain bioelements in soils and drinking water or non-compliance with its stable chemical composition causes the development of dysmicroelementosis. The ecological situation of the Carpathian region is closely related to the state of soils and water resources. In this regard, it is advisable to study and control the level of cadmium compounds in the environment of the region. The study of the effect of cadmium intoxication on the macro- and microelement composition of the brain and myocardium of experimental animals is also worthwhile. Materials and methods. Soils and drinking water of the plain, foothill and mountainous zones of the region, as well as organs and tissues of experimental animals served as the object of research. Cadmium levels in drinking water and myocardial tissues and brain of experimental animals have been measured by atomic absorption spectroscopy. Results and discussion. The study of soils in the Prykarpattia region has revealed an increase in the toxic element cadmium. Its content is 1.1-1.5 times higher than background levels. The analysis of drinking water allowed to establish that a significant number of people living in the plain and foothill zone of the region consume water with a high content of cadmium. The main stages of cadmium intake and accumulation in plants have been analyzed. Significant disorders in the body of experimental animals under conditions of excessive intake of cadmium compounds have been revealed. It was accompanied by the accumulation of cadmium in the myocardium and brain, on the background of redistribution of vital macronutrients calcium and magnesium along with micronutrients copper and zinc. Thus, excessive intake of cadmium salts causes the development of dysmicroelementosis, which is accompanied by a violation of the homeostasis of a living organism. It is suggested to conduct continuous monitoring of the level of toxicants in the ecosystem as an integral component of environmental monitoring.

Indirect effects of oil products on the environment

The article is focused on chemical and radioactive contamination of the environment during hydrocarbon production. The objective of the research is to present relatively unknown facts of indirect long-term environmental effects of hydrocarbon production. Traces of radioactive contamination of soils, ground- and surface water were studied, and also in drinking water in the Republic of Bashkortostan. The authors’ own field and laboratory studies were used. They were performed as part of the preparation of geochemical base map (GHO-1000) of 1:1000000 scale in the Republic of Bashkortostan and in the Ukhto-Izhemsky oil and gas bearing region. The methods applied for laboratory research were inductively coupled plasma mass spectrometry (ICP-MS) for soil and bottom sediment samples and atomic emission spectrometry (ICP-AMS) for ground- and surface waters. It has been determined that in the areas affected by oil production the chemical pollution aspects include deterioration of the groundwater quality caused by associated water and oil products ingress into aquifers due to violation of the oil and gas well drilling techniques, and soil salination caused by frequent equipment breaks during oil production. Aspects of radiation contamination of the environment during oil production include the intake of radionuclides with associated water, and sometimes with heavy hydrocarbon fractions, as well as the consequences of underground nuclear explosions. It is concluded that the territories of hydrocarbon exploration, production and storage should be classified as areas of potential risk for radioactive contamination and chemical pollution (by inorganic compounds, including heavy metal salts). Uranium concentration in drinking water was determined by the INAA method (instrumental neutron activation analysis).

Ағынды суларды отандық көміртек құрамды адсорбенттермен тазарту және су құрамына физика-химиялық талдау жүргізу

Various strategies are being implemented to improve water use efficiency in the face of increasing world population and increasing demand for depleting fresh water sources. Wastewater treatment and reuse are effective strategies, especially if the treated water can be reused. Water scarcity is a growing global problem caused by a combination of factors such as population growth, climate change and unsustainable water management practices.
 This article presents the results of a study in the accredited analytical laboratory of the treatment facilities of the State Industrial Complex "Astana Su Arnasy", where wastewater was treated with domestic carbon-containing adsorbents (Shubarkol, Shoptykol, humic acid, carbon molecular sieves, carbon black) and were carried out with chemical water analysis. The results of this study showed that samples obtained on the basis of carbon materials can be used as adsorbents for purifying liquid media (from suspended solids, heavy metal salts, surfactants, petroleum products, etc.).

Prospects for the use of layer-by-layer technology for the development of an enzyme biosensor used for milk quality control

This article presents the results of scientific research on the development of a biosensor system for the determination of salts of heavy metals (cadmium and lead) in milk. When developing a biosensor system, much attention is paid to the selection of biological material and the method of their stabilization using physical and chemical forces, namely, immobilization. In this regard, studies were carried out on the selection of the enzyme and the method of its immobilization in the development of a biosensor for the detection of salts of heavy metals in milk. The development of a biosensor for the determination of toxic elements in food products is of scientific and practical importance. In world practice, special attention is paid to the contamination of raw materials and food products with toxic chemicals, mainly of anthropogenic origin, which are persistent organic pollutants. Therefore, quality control of raw materials, food products is important for consumers, and, accordingly, for the food industry. Experimental studies are based on the methods of Filippova A. M., Vorobieva O. V. to determine the specific activity of the enzyme acetylcholinesterase. Determination of the activity of the catalase enzyme was carried out in accordance with the gasometric method according to the method of Warburg. As a result of experimental studies, the catalase enzyme as a biological material was chosen as a sensitive element. As a carrier for the immobilization of enzymes, a 5-bilayer combination of "chitosan-sodium alginate" was selected. The layer-by-layer technology was used to immobilize the enzyme on the substrate surface when creating an enzyme biosensor. The results of the research are recommended to be applied in the study of food safety issues and in the assessment of safety indicators of raw materials and food products by the express method.

DETERMINATION OF BIOLOGICALLY ACTIVE COMPOUNDS IN LIQUID EXTRACT OF PLANTS POLYGONUM HIDROPIPER L., BURSA PASTORIS, CALENDULAE OFFICINALIS AND URTICA DIOICA L.

Methods have been developed for the quantitative determination of biologically active compounds - flavonoids and vitamin K1 in the liquid extract "Extradent" obtained from the aerial part of the knotweed (Polygonum hidropiper L.), shepherd's purse (Bursa pastoris), calendula flowers (Calendulae officinalis) and nettle leaves (Urtica dioica). L.), by high performance liquid chromatography (HPLC). As a result, components corresponding to the retention time of standard samples of robinin, rutin, and quercetin were found on the chromatogram of the extract. It was revealed that the content of robinin was 0.37%, rutin 0.014%, quercetin 0.00045%, and vitamin K1 0.005%. The same method of mass spectrometry with inductively coupled plasma (ICP-MS) was used to determine the quantitative content of macro- and microelements of the liquid extract "Extradent". The highest content of macroelements is in the proportion of potassium (0.65%), phosphorus (0.2%), and among the microelements of iron is 15.716 mg/l, selenium – 0.046 mg/l. The content of heavy metal salts in the liquid extract is within the normal range and totals 1.155 mg/l. Of these, the main content is zinc and copper.

Development of Novel Redox-Active Organic Materials Based on Benzimidazole, Benzoxazole, and Benzothiazole: A Combined Theoretical and Experimental Screening Approach.

Sustainability is one of the hot topics of today's research, in particular when it comes to energy-storage systems such as batteries. Redox-active molecules implemented in organic batteries represent a promising alternative to lithium-ion batteries, which partially rely on non-sustainable heavy metal salts. As an alternative, we propose benzothiazole, -oxazole and -imidazole derivatives as redox-active moieties for polymers in organic (radical) batteries. The target molecules were identified by a combination of theoretical and experimental approaches for the investigation of new organic active materials. Herein, we present the synthesis, electrochemical characterization and theoretical investigation of the proposed molecules, which can later be introduced into a polymer backbone and used in organic polymer batteries.