Nanosized Form Research Articles

Active packaging films based on the nanoform of chitin, alginate, and layered double hydroxides: characterization, mechanical properties, permeability, and bioactive properties.

Their unique characteristics make plastic films frequently utilised for packaging products. However, this petroleum-derived material has a long history of being linked to environmental contamination and hazardous degradation. Petroleum plastic can be substituted with edible packaging. The objective of this study was to combine sodium alginate with chitin, both in their nanosized form to formulate active packaging films containing different ratios of Zn/Al-layered double hydroxides (LDHs). Subsequently, active packaging films were formulated via a green method with different percentages (0%, 1%, 3%, and 5% w/w) of LDHs. The LDH particles were shaped as rectangular rods with a length of about 60 nm and width of around 20 nm. The films were evaluated for their physicochemical, topological, thermal, mechanical, water vapour, oxygen permeability and antimicrobial properties. Results indicated that active packaging with LDHs (3%) enhanced mechanical properties (tensile strength) by two-fold. Moreover, the addition of LDHs led to decreased permeability properties. Additionally, the antimicrobial study showed that the films with LDHs possessed a broad spectrum of antibacterial and antifungal activities, and the time required for bacterial killing was recorded to be less than 16 hours for films containing 5% LDHs. Thus, the formulated films show potential for use as active packaging.

Adsorption of Guanine on Oxygen-Deficient TiO2 Surface: A Combined MD-DFTB/DFT Strategy.

Metal oxides (MOs) are key materials in many fields, including technological, industrial, and biomedical applications. In most of these implementations, surface reactivity and reducibility properties are critical considerations. In their nanosized form, MOs exhibit enhanced reactivity that is connected to toxicity. Besides the fact that the biological molecule and the surface of the corresponding material interact chemically, little is known about the toxicological mechanisms involved on the atomic scale. The goal of this study is to investigate the role of TiO2 surfaces in interaction with one genetic base, namely guanine. Using a combination of the quasi-electronic density functional-tight binding molecular dynamics simulations and density functional theory calculations, we explored the adsorption modes of guanine with a stoichiometric and oxygen-deficient anatase TiO2 (101) surface. With such an approach, we have characterized new adsorption modes not previously found, and we have highlighted the relevance of defective surfaces in the adsorption of genetic basis, as a model for explaining possible toxicology mechanisms induced by the adsorption process.

Synthesis, In-Vitro, In-Vivo screening, and molecular docking of disubstituted aminothiazole derivatives and their selenium nanoparticles as potential antiparkinson agents

Neurological illnesses are among the leading causes of mortality across the world. In the present work, the synthesis of a new series of substituted aminothiazole derivatives (3a-e) as antiparkinsonian agents is reported. Furthermore, aminothiazoles 3a-e were used for in-situ synthesis of selenium nanoparticles 3a(SeNP)-3e(SeNP) to boost the CNS activities and potency. Selenium nanoparticles were confirmed using UV–Vis spectrophotometry, TEM, particle size distribution, and zeta potential. All selenium nano-sized forms elicited greater in-vitro inhibitory activity against both hMAO isoforms when compared to their corresponding normal-sized ones. Compound 3b was the most potent MAO-B inhibitor with an IC50 value of 0.11 µM. Its nano-sized form 3b(SeNP) showed improved hMAO-B inhibitory activity with an IC50 value of 0.033 µM which surpasses its normal-sized action (3b) by 70%. Molecular docking studies of compound 3b displayed interaction at the active sites of both hMAO-A and hMAO-B isoforms in an inhibitory mode similar to co-crystalized ligands. The antiparkinson effect of both 3b and 3b(SeNP) was further screened by using an in-vivo model of haloperidol-induced Parkinson's disease in rats. Behavioral tests in rats revealed that the nanoparticle formulation showed a superior effect on exploratory activity as an antiparkinsonian agent. Accordingly, this nanotechnology-based approach can be a promising lead for developing novel and potent treatments for neurodegenerative diseases.

Pharmaceutical Nanoparticles Formation and Their Physico-Chemical and Biomedical Properties.

The use of medicinal substances in nanosized forms (nanoforms, nanoparticles) allows the therapeutic effectiveness of pharmaceutical preparations to be increased due to several factors: (1) the high specific surface area of nanomaterials, and (2) the high concentration of surface-active centers interacting with biological objects. In the case of drug nanoforms, even low concentrations of a bioactive substance can have a significant therapeutic effect on living organisms. These effects allow pharmacists to use lower doses of active components, consequently lowering the toxic side effects of pharmaceutical nanoform preparations. It is known that many drug substances that are currently in development are poorly soluble in water, so they have insufficient bioavailability. Converting them into nanoforms will increase their rate of dissolution, and the increased saturation solubility of drug nanocrystals also makes a significant contribution to their high therapeutic efficiency. Some physical and chemical methods can contribute to the formation of both pure drug nanoparticles and their ligand or of polymer-covered nanoforms, which are characterized by higher stability. This review describes the most commonly used methods for the preparation of nanoforms (nanoparticles) of different medicinal substances, paying close attention to modern supercritical and cryogenic technologies and the advantages and disadvantages of the described methods and techniques; moreover, the improvements in the physico-chemical and biomedical properties of the obtained medicinal nanoforms are also discussed.

Обогащение молочных продуктов биологически активными формами селена

The article describes the effect of a new biologically active form of selenium on cow’s milk as a dispersed system. The authors developed new methods to stabilize selenium nanoparticles with food additive E433 and studied the physicochemical profile of the fortified milk. The biologically active nanosized form of selenium was studied by transmission electron microscopy. Its effect on the dispersed milk system was assessed by the changes in pH and the average hydrodynamic radius of the milk system on storage day 5. Selenium particles were 52 nm in size. The biologically active selenium had no significant effect on milk components. The resulting functional milk product demonstrated strong antioxidant activity, which exceeded Trolox equivalent by 26 %. In this study, the biologically active nanoselenium was able to integrate into the colloidal system of milk and functionalize it.

Methods of Atomic Spectroscopy in Studying Properties and the Behavior of Nanoscale Magnetic Materials in Biological Systems

In this review, we provide an overview of methods for synthesizing magnetic nanoparticles (MNPs) with potential applications to biomedical research. We explore how the structure and properties of these particles are related to their diverse uses in medical diagnostics and bioanalysis. Special emphasis is placed on MNPs containing noble metals, which serve as biomarkers or active agents. Specifically, we focus on the application of direct and combined methods of atomic spectroscopy (ETAAS, AES/ICP–MS) to biomedical research. Experimental approaches to studying the behavior and transformations of MNPs in vitro and in vivo are considered. The importance of proper sample preparation in simulating the behavior of nanoparticles in biological media is highlighted. We also examine the significance of preparation techniques for the accurate determination of dissolved and nanosized forms in biological samples. Lastly, we assess the potential for the comprehensive studies of MNP behavior within complex biological systems, pointing toward future directions in this dynamic and promising field of research.

Effect of the association of microparticles and nano-sized β-calcium glycerophosphate in conventional toothpaste on enamel remineralization: In situ study

ObjectivesThis in situ study aimed to assess the remineralizing effect of a fluoride toothpaste supplemented with β-calcium glycerophosphate in both micro (β-CaGPm) and nano-sized forms (β-CaGPn). MethodsThis blind and cross-over study was performed in 4 phases, each spanning 3 days. Twelve volunteers utilized palatal appliances containing four bovine enamel blocks with artificial caries lesions. Volunteers were randomly assigned to the following treatment groups: Placebo (no F-β-CaGPm-β-CaGPn); 1100 ppm F alone (1100F); 1100F plus 0.5% micrometric β-CaGP (1100F-0.5%β-CaGPm); and 1100F plus 0.25%nano-sized β-CaGP (1100F-0.25%β-CaGPn). Participants were instructed to brush their natural teeth with the palatal appliances in the mouth for 1 min (3 times/day), ensuring that the enamel blocks were exposed to the natural toothpaste slurries. Following each phase, evaluations were conducted to determine the percentage of surface hardness recovery (%SHR), integrated recovery of subsurface hardness (ΔIHR), profile subsurface lesion through polarized light microscopy (PLM), as well as fluoride (F), calcium (Ca), and phosphorus (P) concentrations within the enamel. Data were analyzed by ANOVA and Student-Newman-Keuls test (p < 0.001). ResultsTreatment with 1100F-0.25%β-CaGPn resulted in %SHR ∼69 % and ∼40 % higher when compared to 1100F and 1100F-0.5%β-CaGPm (p < 0.001). The reduction in lesion body (ΔIHR; PLM) was ∼40 % higher with 1100F-0.25%β-CaGPn (p < 0.001) compared to 1100F. The addition of β-CaGPm and β-CaGPn did not influence enamel F concentration (p > 0.001). Treatment with 1100F-0.25%β-CaGPn led to an increase in the concentration of Ca and P in the enamel (p < 0.001). ConclusionThe addition of 0.25%β-CaGPn into 1100F formulation increased the bioavailability of calcium and phosphate, promoting a higher remineralizing effect. Clinical significanceToothpaste containing 1100F-0.25%β-CaGPn showed a potential of higher remineralization to 1100 ppm F and 1100 ppm F micrometric β-CaGP could be a strategy for patients at caries activity.

Nanotechnology-Based Drug Delivery Approaches of Mangiferin: Promises, Reality and Challenges in Cancer Chemotherapy.

Mangiferin (MGF), a xanthone derived from Mangifera indica L., initially employed as a nutraceutical, is now being explored extensively for its anticancer potential. Scientists across the globe have explored this bioactive for managing a variety of cancers using validated in vitro and in vivo models. The in vitro anticancer potential of this biomolecule on well-established breast cancer cell lines such as MDA-MB-23, BEAS-2B cells and MCF-7 is closer to many approved synthetic anticancer agents. However, the solubility and bioavailability of this xanthone are the main challenges, and its oral bioavailability is reported to be less than 2%, and its aqueous solubility is also 0.111 mg/mL. Nano-drug delivery systems have attempted to deliver the drugs at the desired site at a desired rate in desired amounts. Many researchers have explored various nanotechnology-based approaches to provide effective and safe delivery of mangiferin for cancer therapy. Nanoparticles were used as carriers to encapsulate mangiferin, protecting it from degradation and facilitating its delivery to cancer cells. They have attempted to enhance the bioavailability, safety and efficacy of this very bioactive using drug delivery approaches. The present review focuses on the origin and structure elucidation of mangiferin and its derivatives and the benefits of this bioactive. The review also offers insight into the delivery-related challenges of mangiferin and its applications in nanosized forms against cancer. The use of a relatively new deep-learning approach to solve the pharmacokinetic issues of this bioactive has also been discussed. The review also critically analyzes the future hope for mangiferin as a therapeutic agent for cancer management.

Assessing the Genotoxicity of Cellulose Nanomaterials in a Co-Culture of Human Lung Epithelial Cells and Monocyte-Derived Macrophages.

Cellulose micro/nanomaterials (CMNMs) are innovative materials with a wide spectrum of industrial and biomedical applications. Although cellulose has been recognized as a safe material, the unique properties of its nanosized forms have raised concerns about their safety for human health. Genotoxicity is an endpoint that must be assessed to ensure that no carcinogenic risks are associated with exposure to nanomaterials. In this study, we evaluated the genotoxicity of two types of cellulose micro/nanofibrils (CMF and CNF) and one sample of cellulose nanocrystals (CNC), obtained from industrial bleached Eucalyptus globulus kraft pulp. For that, we exposed co-cultures of human alveolar epithelial A549 cells and THP-1 monocyte-derived macrophages to a concentration range of each CMNM and used the micronucleus (MN) and comet assays. Our results showed that only the lowest concentrations of the CMF sample were able to induce DNA strand breaks (FPG-comet assay). However, none of the three CMNMs produced significant chromosomal alterations (MN assay). These findings, together with results from previous in vitro studies using monocultures of A549 cells, indicate that the tested CNF and CNC are not genotoxic under the conditions tested, while the CMF display a low genotoxic potential.

Phylogenesis of gold in polymetallic volcanogenic-sedimentary massive sulfide ores

The Au concentrational level of the ores of polymetallic volcanogenic-sedimentary massive sulfide deposits is predetermined by the geodynamic setting of their formation. The ores formed in a mid-ocean ridge setting are characterized by low Au grades. The ores formed under the island arc conditions possess higher Au contents. In the course of the further existence of the ore deposit, its ores experience repeated external influences: underwater halmyrolysis, thermal and dynamic metamorphism, hydrothermal-metasomatic transformations, and exogenous oxidation. These processes lead to the transfer of gold from a micro- or nano-sized form in the sulfides to the free form and to redistribution of Au over the ore field of the deposit. The heterogeneity of the ores in terms of the Au content and existence forms must be taken into account when preparing a feasibility study. The work is intended for geologists conducting mining and geological modeling, designing techniques for the ore extraction, and proposing ore processing technologies.

Novel pyrimidine Schiff bases and their selenium-containing nanoparticles as dual inhibitors of CDK1 and tubulin polymerase: design, synthesis, anti-proliferative evaluation, and molecular modelling

Nanotechnology-based strategies can overcome the limitations of conventional cancer therapies. Hence, novel series of pyrimidine Schiff bases (4–9) were employed in the synthesis of selenium nanoparticle forms (4NPs–9NPs). All selenium nano-sized forms exerted greater inhibitions than normal-sized compounds, far exceeding 5-fluorouracil activity. Compound 4 showed effective anti-proliferative activity against MCF-7(IC50 3.14 ± 0.04 µM), HepG-2(IC50 1.07 ± 0.03 µM), and A549(IC50 1.53 ± 0.01 µM) cell lines, while its selenium nanoform 4NPs showed excellent inhibitory effects, with efficacy increased by 96.52%, 96.45%, and 93.86%, respectively. Additionally, 4NPs outperformed 4 in selectivity against the Vero cell line by 4.5-fold. Furthermore, 4NPs exhibited strong inhibition of CDK1(IC50 0.47 ± 0.3 µM) and tubulin polymerase(IC50 0.61 ± 0.04 µM), outperforming 4 and being comparable to roscovitine (IC50 0.27 ± 0.03 µM) and combretastatin-A4(IC50 0.25 ± 0.01 µM), respectively. Moreover, both 4 and 4NPs arrested the cell cycle at G0/G1 phase and significantly forced the cells towards apoptosis. Molecular docking demonstrated that 4 and 4NPs were able to inhibit CDK1 and tubulin polymerase binding sites.

Pre and postharvest characteristics of Dahlia pinnata var. pinnata, cav. As affected by SiO2 and CaCO3 nanoparticles under two different planting dates

Agriculture faces many challenges because of climate changes. The nutrients present in nano-sized form improve plant productivity, especially when used at the appropriate planting time. Field experiments were conducted as a factorial experiment for evaluating two planting dates (20th September and 20th October), foliar application with nanoparticles (NPs) including silica nanoparticles (SiO2-NPs) at 1.5 and 3 mM, calcium carbonate nanoparticles (CaCO3-NPs) at 5 and 10 mM and distilled water (control) on pre- and post-harvest characteristics of Dahlia pinnata var. pinnata Cav. The results indicate that the interactions during the late planting time (20th October) and exogenous applications of SiO2-NPs at 1.5 mM or CaCO3-NPs at 10 mM have improved plant growth including plant height, stem diameter, fresh and dry weights of plant, leaf area, inflorescence diameter, inflorescence stalk length, branches number, tuber numbers, inflorescences number on the plant, and the vase life. At the same time, insignificant differences appeared in the interaction during the planting dates and SiO2 or CaCO3 -NPs concentrations on inflorescence stalk diameter, total soluble solids, membrane stability index, maximum increase in fresh weight (FW), and Si and Ca contents. In addition, all exogenous applications of NPs at the late planting time promoted the plant growth characteristics like lignin %, cellulose %, inflorescence water content, change in FW, and total water uptake. Moreover, the controls through the two planting dates recorded the maximum change in water uptake and water loss values. In short, it can be recommended to use SiO2-NPs at 1.5 mM or CaCO3-NPs at 10 mM as a foliar application at the late planting time (20th October) for obtaining the optimum quantitative and qualitative parameters of D. pinnata.

Nanometals and Metal Ion Pollution from Dental Materials in Dental Environment

The dental environment is being polluted with metals from dental materials in many ways, mainly due to aerosol-generating procedures; this could affect the long-term well-being of dentists, dental students, and dental personnel. The current dental pollution incorporates metallic nanoparticles, which are highly reactive and quickly become airborne, especially those particles that become unbound in the bulk composition. In addition, liquid mercury or mercury vapors may be released from dental amalgam, causing concerns in the dental community. In our study, we reviewed the behavior of metallic elements present in dental materials, their routes of exposure, and their potentially toxic effects on the dental team. This review found that skin and lung disorders are the most harmful effects of metallic exposure for dentists, dental students, and dental personnel. Therefore, chronic exposure to low concentrations of metals in the dental environment, especially in nanosized forms, should be further investigated to improve the environmental matrix, material choice, and safety protocols.

The state of metabolic parameters of the blood in white rats under conditions of long-term oral administration of gadolinium orthovanadate nanoparticles under food stress

The prohibition of using antibiotics with growth-stimulating properties in the European Union led to the search for new, safer, more effective, and cheaper feed additives. One of these substances was rare earth elements (REE, atomic numbers 57–71) due to their low toxicity and protective and antioxidant properties. At the same time, higher efficiency of organic forms of REE was noted. Thanks to this, it is possible to assume their even more pronounced effect in nano-sized form as feed additives and the need to conduct research in this direction. Therefore, this work aims to study the metabolic parameters of the blood in rats under long-term oral administration of nanoparticles of one of the representatives of rare earth elements – gadolinium orthovanadate (NP GdVO4:Eu3+) under food stress. Experimental samples of gadolinium orthovanadate nanoparticles activated by Europium (spindle-shaped geometry; size 8×25 nm; initial concentration 1.0 g/dm3) were used in work. Experimental studies on rats were carried out based on the vivarium of the NSC “IEKVM”. The object of research was 140 mature male Wistar rats with an initial weight of 180–200 g. Four groups of animals, 35 rats each, were formed according to the principle of analogs. During the experiment, animals of the control group received drinking water without additives; rats of the І experimental group were given a solution of NP GdVO4:Eu3+ at a dose of 0.2 mg/dm3 (≈ 0.03 mg/kg of body weight); II research group – at a dose of 1.0 mg/dm3 (≈ 0.15 mg/kg of body weight) and rats of III research group – at a dose of 2.0 mg/dm3 (≈ 0.30 mg/kg of body weight). Drinking was carried out for 56 days, then it was completed, and the rats were observed for another 14 days. A nutritionally unbalanced diet was used as a stress factor. Taking into account the results of biochemical studies, the adaptogenic effect of NP GdVO4:Eu3+ in the range of doses of 0.2–1.0 mg/dm3 of drinking water (≈ 0.03–0.15 mg/kg of body weight) on the body of white rats was established under conditions of food stress with optimal duration of action – 28–42 days. Under the conditions of administration at a dose of 2.0 mg/dm3 of drinking water (≈ 0.30 mg/kg of body weight), a hepatic(cyto-)toxic effect of nanoparticles was detected, which was accompanied by an irreversible decrease in the structural indicators of lipid metabolism, the consumption of antioxidant resources and the induction of intensity processes of lipid peroxidation against the background of alanine aminotransferase hyperenzymemia.

Characterization and Biological Studies of Synthesized Titanium Dioxide Nanoparticles from Leaf Extract of Juniperus phoenicea (L.) Growing in Taif Region, Saudi Arabia

Green synthesis of metal nanoparticles in nanosized form has acquired great interest in the area of nanomedicine as an environmentally friendly and cost-effective alternative compared to other chemical and physical methods. This study deals with the eco-friendly green synthesis of titanium dioxide nanoparticles (TiO2 NPs) utilizing Juniperus phoenicea leaf extract and their characterization. The biosynthesis of TiO2 NPs was completed in 3 h and confirmed by UV-Vis spectroscopy, a strong band at 205.4 nm distinctly revealed the formation of NPs. Transmissions electron microscopy (TEM) analysis showed the synthesized TiO2 NPs are spherical in shape, with a diameter in a range of 10–30 nm. The XRD major peak at 27.1° congruent with the (110) lattice plane of tetragonal rutile TiO2 phase. Dynamic light scattering (DLS) analysis revealed synthesized TiO2 NPs average particle size (hydrodynamic diameter) of (74.8 ± 0.649) nm. Fourier transmission infrared (FTIR) revealed the bioactive components present in the leaf extract, which act as reducing and capping agents. The antimicrobial efficacy of synthesized TiO2NPs against, Staphylococcus aureus, and Bacillus subtilis (Gram-positive), Escherichia coli and Klebsiella pneumoniae (Gram-negative), Yeast strain (Saccharomyces cerevisiae) and fungi (Aspergillus niger, and Penicillium digitatum) assayed by a disc diffusion method. TiO2NPs inhibited all tested strains by mean inhibition zone (MIZ), which ranged from the lowest 15.7 ± 0.45 mm against K. pneumoniae to the highest 30.3 ± 0.25 against Aspergillus niger. The lowest minimum inhibitory concentration (MIC) and bactericidal (MBC) values were 20 μL/mL and 40 μL/mL of TiO2NPs were observed against Asp. niger. Moreover, it showed significant inhibitory activity against human ovarian adenocarcinoma cells with IC50 = 50.13 ± 1.65 µg/mL. The findings concluded that biosynthesized TiO2 NPs using Juniperus phoenicea leaf extract can be used in medicine as curative agents according to their in vitro antibacterial, antifungal, and cytotoxic activities.

Waste valorization by nanotechnology approaches for sustainable crop protection: a mini review

Agri-food waste management represent for several supply-chains a pending issue, since most of the lignocellulosic biomasses produced by the agricultural practices are often intended for energy production, due to their high disposal costs. Nanotechnology could represent a sustainable way to valorise agricultural waste by extracting highly performing nanomaterials and reusing them as nanocarriers or nanopesticides to protect crops. Cellulose and lignin, which are the main component of plant residues display antimicrobial properties when reduced to their nanosized forms, being able to act as innovative tools to counteract plant pathogens, both bacterial and fungal ones. In particularly cellulose can be extracted from different matrices to obtain cellulose nanocrystals (CNC), while lignin is often reduced in nanoparticles (LNP). In this mini review the current and most recent results in terms of antimicrobial activities against plant pathogens by waste-based lignocellulosic nanomaterial are showed.

Does Nanosilver Have a Pronounced Toxic Effect on Humans?

Due to the development of high-tech industries, the modern world is characterized by the increased production and consumption of nanoparticles (NPs) and nanomaterials. Among produced metal nanoparticles, silver nanoparticles are widely used in everyday life products, cosmetics, and medicine. It has already been established that, in nanoscale form, many even inert materials become toxic. Therefore, the study of the toxicity of various substances in nanoscale form is an urgent scientific task. There is now a body of experience on the toxic effect of AgNPs. In the present review, the most well-known results obtained over the 2009–2021 period, including the own performance on the toxicity of silver NPs, are collected and analyzed. Along with the data reporting a certain level of toxicity of silver NPs, experiments that did not reveal any obvious toxicity of nanosized forms of silver are discussed. According to the performed studies, the toxicity of silver NPs is often caused not by NPs themselves but by silver ions, compounds used for nanoparticle stabilization, and other reasons. Based on the analysis of the collected data, it can be concluded that at actual levels of silver NPs used in everyday life, workplace, and medicine, they will not have strong toxic effects on a healthy adult body.

THE MAIN WAYS FOR METAL NANOPARTICLES DEGRADATION

Progress of nanotechnology development regulates the production of substance in nanosized form, including metal nanoparticles. Therefore, they can enter agricultural land in different ways. Consequently, their further role in agrocenosis is the prerogative of modern research. So, the main issue today remains the possibility of destruction of nanotechnology products at the expense of both edaphic factors and metabolic products of plants and microorganisms to avoid their accumulation in agrophytocenoses. This article presents a review, mostly of foreign literature, to systematize knowledge of degradation pathways, mechanisms of nanoparticle penetration into the cell, their subsequent transport through tissues, and the interaction of metal nanoparticles with the environment in agrobiocenoses. Physicochemical properties of metal nanoparticles (for example, size, charge, shape, coating) and soil properties (for example, pH, mineral composition, presence of organic acids, etc.) play an important role in elucidating the issues of decomposition, transport, mobility and interaction of nano-containing preparations with soil components . The main role in the formation of most morphological features of metal nanoparticles, which are the basis of nano-containing preparations, played by the method of nanoparticle synthesis. Among many existing ones, in particular, transformation in plasma by evaporation, deposition of powders from solutions on a substrate, gas-phase synthesis, and others, the electrospark dispersion method was released as the most modern and progressive, since for detailed analysis we can perfectly reproduce the synthesis process of nano-containing solutions, by this method. With the help of our own method of synthesis, by adjusting the parameters of nano-containing preparations, it is possible to predict and avoid the potential risks of using nano-containing preparations of metals in phytocenosis. Therefore, the main goal of this review is to evaluate the potential of metal nanoparticles for degradation, to describe the prerequisites for biodegradation and to note the main possibilities of using such properties in the agro-industrial complex.

СЕЛЕН В НАНОФОРМЕ: ТОКСИЧНОСТЬ И БЕЗОПАСНОСТЬ

The review is devoted to the compilation of data on the toxicity and safety of using nanosized forms of selenium. It is shown that in nature selenium exists mainly in the form of selenate (Se6+), selenite (Se4+), selenide (Se2–) and elemen-tal selenium (Se0), while the latter is insoluble in aqueous media, less toxic and biologically inert. Elemental selenium in the form of nanosized particles is not only biocompatible, but also has antitumor and antimicrobial activity. It was shown that elemental selenium in the form of nanoparticles can modulate the activity of the antioxidant and detoxification systems. A data on the dose-dependent effect of selenium in nanosized form was presented. It was demonstrated that selenium nanoparticles in high concentrations (above 2 mg of Se per 1 kg of animal weight) can cause the development of selenium-induced toxicity in mammals. It was shown that elemental selenium in the form of nanoparticles can affect immunoregulation, reproductive func-tion, kidney and liver function, can modulate the activity of the antioxidant and detoxification systems, and in high concentrations (above 2 mg of Se per 1 kg of animal weight) it can cause the development of selenium-induced toxicity both in mammals and fish. At the same time, it was shown that for fish selenium nanoparticles are more toxic than inorganic selenium and cause a more acute reaction of the body to exposure to even low concentrations, which is possibly associated with hyperaccumulation of selenium in tissues. This fact once again reminds us of the need to take into account the problems of ecotoxicity of selenium nanocomposites.

Development of the Composition and Technology for Obtaining Paclitaxel Nanoscale Formulation Consisting of a Conjugate of Polymer Particles with a Protein Vector Molecule

Introduction. The use of the anticancer drug paclitaxel is limited due to its high toxicity and lipophilicity. A new polymer composition of paclitaxel has been proposed, which provides targeted transport of the drug into tumor cells and improves its safety.Aim. Method development for preparation of a novel paclitaxel formulation consisting of a conjugate of PLGA nanoparticles with the third domain of alpha-fetoprotein.Materials and methods. The object of this study is paclitaxel-loaded nanoparticles based on a copolymer of lactic and glycolic acids, the surface of which is modified with a vector molecule - the recombinant third domain of alpha-fetoprotein. Nanoparticles were obtained by single emulsification method and precipitation. Conjugation with a protein molecule was performed by the carbodiimide method. The analysis of the obtained nanoparticles was carried out using dynamic and electrophoretic light scattering, high performance liquid chromatography, dialysis membrane method.Results and discussion. Synthesis of paclitaxel-loaded nanoparticles based on a copolymer of lactic and glycolic acids and its conjugation optimization under varying a wide range of conditions have been carried out. The resulting conjugate had an average diameter of 280 ± 12 nm. The conjugation efficiency was 95 %. The release of paclitaxel from the polymer matrix in the release medium was 65 % in 220 h.Conclusions. A method of obtaining and substantiating the composition of the original nanosized form of paclitaxel is proposed. The possibility of prolonged release of paclitaxel from the polymer matrix has been shown.