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1.
ACS Omega ; 9(34): 36220-36231, 2024 Aug 27.
Artigo em Inglês | MEDLINE | ID: mdl-39220526

RESUMO

In today's medicine, progress often depends on new products with special qualities. Nanotechnology focuses on the creation of materials tailored to fulfill specific therapeutic requirements. This study aims to elucidate the potential of nanoparticles, particularly titanium dioxide nanoparticles, as carriers for pharmaceutical agents. To mitigate the release of potentially harmful titanium ions from the carrier's surface, modifications were implemented. In the initial phase, titanium dioxide, nanoparticles were obtained based on the sol-gel method, and their surfaces were coated with galactose. Characterization of these materials encompassed analysis of the particle size, specific surface area, microscopic morphology, and titanium ion release. Additionally, drug release profiles, particularly those of tadalafil, were investigated. In vitro assessments were conducted to evaluate the cytotoxic and mutagenic effects of the developed materials on CHO cells. The findings revealed a reduction in titanium ion release from the modified carrier compared to its unmodified counterpart. Pharmacokinetic studies in rats demonstrated enhanced absorption of the drug when the drug was delivered using the modified carrier. The synthesized materials exhibited high purity and favorable surface properties conducive to effective drug-carrier interactions. The results suggest that the modified titanium dioxide nanoparticles hold promise as efficient drug delivery vehicles in biomedical applications.

2.
J Phys Chem B ; 128(33): 8007-8016, 2024 Aug 22.
Artigo em Inglês | MEDLINE | ID: mdl-39120940

RESUMO

Nanozymes are nanoscale materials that exhibit enzymatic-like activity, combining the benefits of nanomaterials with biocatalytic effects. The addition of metals to nanomaterials can enhance their nanozyme activity by mimicking the active sites of enzymes, providing structural support and promoting redox activity. In this study, nanostructured oxide and silicate-phosphate nanomaterials with varying manganese and copper additions were characterized. The objective was to assess the influence of metal modifications (Mn and Cu) on the acquisition of the nanozymatic activity by selected nanomaterials. An increase in manganese content in each material enhanced proteolytic activity (from 20 to 40 mUnit/mg for BG-Mn), while higher copper addition in glassy materials increased activity by 40%. Glassy materials exhibited approximately twice the 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid radical activity (around 40 µmol/mL) compared to that of oxide materials. The proteolytic and antioxidant activities discussed in the study can be considered indicators for evaluating the enzymatic properties of the nanomaterials. Observations conducted on nanomaterials may aid in the development of materials with enhanced catalytic efficiency and a wide range of applications.


Assuntos
Cobre , Nanoestruturas , Óxidos , Óxidos/química , Nanoestruturas/química , Cobre/química , Manganês/química , Antioxidantes/química , Antioxidantes/farmacologia , Proteólise , Ácidos Sulfônicos , Benzotiazóis
3.
J Environ Manage ; 367: 121895, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-39059310

RESUMO

The article presents a method for obtaining catalytic systems: SiO2-Fe2O3, SiO2-Fe2O3-Fe and verification of their catalytic properties in the oxidation process of technical soot N550. The process of immobilization of Fe3+ ions on microsilica-SiO2 was investigated in the batch system (equilibrium, kinetics, thermodynamics). The process was aimed at obtaining a system with a developed surface and using less iron while maintaining the same catalysis active surface. In the next stages, the SiO2-Fe3+ systems were modified to obtain SiO2-Fe2O3 and SiO2-Fe2O3-Fe materials, which exhibited catalytic properties. To obtain catalytic systems, the processes of Fe3+ ions sorption, iron oxide precipitation - Fe2O3 and Fe reduction using a plant extract were used. Catalytic systems were applied in the N550 technical soot oxidation process to reduce the conversion temperature and increase its efficiency. The soot oxidation process was carried out in a muffle furnace using variable process parameters, i.e. temperature (450, 475, 500, 525 and 550oC), time (1, 2 and 3h), type of catalytic system (SiO2-Fe2O3, SiO2-Fe2O3-Fe) and its % content relative to the constant mass of soot (0, 10, 20 and 30%). The greatest increase in the conversion efficiency of soot particles was obtained using the SiO2-Fe2O3 system with a content of 20% at a temperature of 550oC and for 3 h.


Assuntos
Compostos Férricos , Oxirredução , Dióxido de Silício , Dióxido de Silício/química , Compostos Férricos/química , Catálise , Ferro/química , Cinética
4.
Materials (Basel) ; 17(13)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38998437

RESUMO

This paper presents the results of research on polyurethane viscoelastic foams (PUVFs) modified with biomaterials. This investigation looked at the effect of the biomaterials on the foaming processes, as well as the acoustical and selected physical-mechanical properties of the foams. Various types of rapeseed oil biopolyols and microcellulose were used to modify the materials. The analysis of properties covered a reference biopolyol-free sample and materials containing 10 wt.%, 20 wt.%, and 30 wt.% of different types of biopolyols in the mixture of polyol components. The biopolyols differed in terms of functionality and hydroxyl value (OHv). Next, a selected formulation was modified with various microcellulose biofillers in the amount of 0.5-2 wt.%. The PUVFs, with apparent densities of more than 210 kg/m3 and open-cell structures (more than 85% of open cells), showed a slow recovery to their original shape after deformation when the pressure force was removed. They were also characterized by a tensile strength in the range of 156-264 kPa, elongation at break of 310-510%, hardness of 8.1-23.1 kPa, and a high comfort factor of 3.1-7.1. The introduction of biopolyols into the polyurethane system resulted in changes in sound intensity levels of up to 31.45%, while the addition of fillers resulted in changes in sound intensity levels of up to 13.81%.

5.
Nanomaterials (Basel) ; 13(6)2023 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-36986024

RESUMO

In this article, we provide an overview of the progress of scientists working to improve the quality of life of cancer patients. Among the known methods, cancer treatment methods focusing on the synergistic action of nanoparticles and nanocomposites have been proposed and described. The application of composite systems will allow precise delivery of therapeutic agents to cancer cells without systemic toxicity. The nanosystems described could be used as a high-efficiency photothermal therapy system by exploiting the properties of the individual nanoparticle components, including their magnetic, photothermal, complex, and bioactive properties. By combining the advantages of the individual components, it is possible to obtain a product that would be effective in cancer treatment. The use of nanomaterials to produce both drug carriers and those active substances with a direct anti-cancer effect has been extensively discussed. In this section, attention is paid to metallic nanoparticles, metal oxides, magnetic nanoparticles, and others. The use of complex compounds in biomedicine is also described. A group of compounds showing significant potential in anti-cancer therapies are natural compounds, which have also been discussed.

6.
Materials (Basel) ; 16(2)2023 Jan 09.
Artigo em Inglês | MEDLINE | ID: mdl-36676363

RESUMO

Natural deep eutectic solvents (NDESs), as a new type of green solvent, are used in many fields, including industry in extraction processes, medicine, pharmaceuticals, metallurgy, electrodeposition, separations, gas capture, biocatalysis and nanotechnology. Mainly due to their properties, such as simple preparation, environmental friendliness, biocompatibility and multifunctionality, they are being used in various fields of industry. This review aims to provide insight into the applications of natural deep eutectic solvents, specifically in nanotechnology processes. It focuses on the description of NDES and how their physicochemical properties are used to obtain functional nanomaterials, including metals, metal oxides and salts. It highlights how the use of NDESs to obtain a wide range of inorganic nanoparticles enables the elimination of disadvantages of traditional methods of obtaining them, including reducing energy consumption and functionalising nanoparticles in situ. In conclusion, recent advances and future directions in the development and applications of NDESs in nanotechnology are discussed with the aim of identifying unexplained scientific questions that can be investigated in the future.

7.
Nanotechnology ; 33(43)2022 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-35820406

RESUMO

Growing international problem with pathogens acquiring resistance to antibiotics is the reason for the search for bactericidal substances against which microorganisms cannot become resistant. The aim of this study was to synthesize inorganic-organic nanohybrids and obtain materials with antimicrobial effects. Chitosan (CS) was deposited on nanocomposite carriers such as calcium oxide with titanium dioxide (CaO-TiO2), magnesium oxide with titanium dioxide (MgO-TiO2) and copper(II) oxide with titanium dioxide (CuO-TiO2). The efficiency of the process was examined at varying concentrations of chitosan and temperature. The parameters for nanohybrids synthesis were selected based on the highest amount of nano-chitosan deposited on the nanohybrids-for each carrier, the process conditions were as follows: chitosan solution at 5 g l-1and 20 °C. The materials were obtained using these parameters and were used for microbiological tests againstE. coliATCC 25922,S. aureusATCC 25923 andC. albicansATCC 10231. The growth inhibitory activity of the obtained materials was qualitatively defined. These results suggest that the synthesized nanohybrids and nanocomposites exhibit biostatic action. The material with the broadest effect was the CuO-TiO2-CS hybrid, which had biostatic properties against all tested strains at a minimal concentration of 1250µg ml-1. Further research is required to find eco-friendly, non-toxic, and more effective antimicrobials with a broad action to prevent the acquisition of resistance.


Assuntos
Anti-Infecciosos , Quitosana , Nanocompostos , Nanopartículas , Antibacterianos/farmacologia , Anti-Infecciosos/farmacologia , Quitosana/farmacologia , Óxidos , Titânio/farmacologia
8.
Environ Sci Pollut Res Int ; 29(18): 27042-27050, 2022 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-34932182

RESUMO

The paper presents the photodegradation process of one-, two- and three-component dye mixtures by ZnO-SnO2 nanoparticles. After 60 min of running the processes, the dye removal efficiencies of 76.44, 72.69, 62.43, 77.00 and 92.46% for MB, RB, TB, MO and YQ degradation, respectively, were obtained. For binary and ternary systems, dye removal efficiencies for all cases exceeded 70%. When the binary and ternary dye mixtures were tested, the photodegradation efficiencies of ZnO-SnO2 were similar to those of the single mixtures, indicating that this material could be used in industrial applications in the future. The focus of the study was to investigate the effect of sorption on photodegradation efficiency and the presence of both cationic and anionic dyes on their degradation efficiency under UV light. The significance of the effect of sorption on the degradation efficiency allowing the interaction of the catalyst with the dyes removed was confirmed. The main factor influencing sorption and consequently photocatalysis was the nature of the dye. It was confirmed that the positively charged ZnO-SnO2 surface effectively sorbs the dyes and causes their degradation.


Assuntos
Corantes , Óxido de Zinco , Catálise , Corantes/metabolismo , Fotólise , Raios Ultravioleta
9.
Artigo em Inglês | MEDLINE | ID: mdl-33979267

RESUMO

The popularity of nanotechnology results from the possibility of obtaining materials that have better chemical, electrical, thermal, mechanical, or optical properties. Nano-sized materials are characterized by an increased surface area, which improves their chemical reactivity and mobility. Due to their enhanced reactivity and appropriately small size, some nanoparticles are used as antimicrobial and antifungal agents. Nanoparticles exhibit antimicrobial potential through multifaceted mechanisms. The adhesion of nanoparticles to microbial cells, and reactive oxygen species, and their penetration inside the cells, have been recognized as the most prominent modes of antimicrobial action. This review presents the mechanism of action of nanometals and oxide nanoparticles used as antimicrobials and the mechanisms of bacterial resistance to the toxic effects of nanoparticles. The article presents methods of forming microorganism resistance to the toxic effects of nanoparticles and the negative impact of nanoparticles on human health.


Assuntos
Anti-Infecciosos/farmacologia , Nanopartículas/química , Nanopartículas/toxicidade , Anti-Infecciosos/química , Anti-Infecciosos/toxicidade , Humanos , Óxidos/química
10.
J Colloid Interface Sci ; 586: 807-818, 2021 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-33198985

RESUMO

HYPOTHESIS: Metal nanoparticles are used as additives in commercial products due to their antimicrobial properties. Apart from their high biocidal activity, it is widely observed that silver nanoparticles are toxic. Simultaneously, copper nanoparticles show fungicidal properties, but with limited effectiveness. Hence, it is suggested that a combination of Ag nanoparticles with Cu nanoparticles may decrease the toxic effects of silver while maintaining their high bioactivity. EXPERIMENTS: This paper presents the properties of Ag and Cu metal nanoparticles, and Ag-Cu and Cu-Ag bimetallic nanoparticles, synthesised in a continuous microwave reactor. The size of the metal nanoparticles obtained was in the range of 27-97 nm, and the size of the bimetallic nanoparticles was in the range of 32-184 nm, depending on the microwave irradiation, residence time, pH of the solution and concentrations of the reagents. FINDINGS: Silver nanoparticles of particle size 97 nm revealed the highest antimicrobial activity (MIC = 10 mg/dm3). Simultaneously, silver nanoparticles did not show viral properties, compared to the copper and bimetallic nanoparticles, for which the virus titre was 1.06-1.50 log TCID50/cm3. In contrast to pure metal nanoparticles, the combination of silver and copper in bimetallic systems generated nanoparticles with no genotoxicity (rac(-)/rac(+) < 1.2).


Assuntos
Nanopartículas Metálicas , Prata , Antibacterianos/farmacologia , Cobre , Nanopartículas Metálicas/toxicidade , Tamanho da Partícula , Prata/farmacologia
11.
Nanotechnology ; 32(2): 025715, 2021 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-32992310

RESUMO

The nanocomposites of nAg-CaCO3 and CaCO3-nAg with different mass content of silver nanoparticles were obtained in a two-stage continuous microwave process. The nanocomposites were characterized by XRD, TEM, UV-vis, and FTIR spectroscopy. The effects of microwave radiation, silver nanoparticles content in the composite and the molar ratio of tannic acid to silver on the size of salt crystallites were studied. The effectiveness of combining silver nanoparticles with CaCO3 was confirmed to exceed 99%. Depending on the input parameters applied, the size of salt crystals in nAg/CaCO3 nanocomposites ranged from 25 to 45 nm, while the size of salt crystals in CaCO3/nAg nanocomposites ranged from 26 to 41 nm. In addition, some of the compositions were tested for their antimicrobial activity on selected yeast and bacterial microorganisms. The prepared materials present a biocidal effect, which makes them suitable for use in antimicrobial preparations.

12.
Int J Pharm ; 585: 119549, 2020 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-32554032

RESUMO

Silver nanoparticles have been used in a range of applications and although they are already employed in medicine, there are new, promising possibilities for their utilization. We investigated the potential of silver nanoparticles obtained with the use of blackcurrant extract in vitro in the LPS-stimulated RAW264.7 macrophages and in vivo in the murine DSS-induced colitis model. The examined formulations contained particles of 95 nm (Ag95) and 213 nm (Ag213) diameter. In vitro, both formulations inhibited nitric oxide (NO) release. In vivo, the preparations alleviated colitis as evidenced by a decreased macroscopic score and myeloperoxidase activity (indicative of neutrophil infiltration). In both cases, the nanoparticles of larger diameter showed better anti-inflammatory properties. Although further tests are required, our results indicate a plausible new use of silver nanoparticles in inflammatory bowel diseases.


Assuntos
Colite/tratamento farmacológico , Nanopartículas Metálicas/química , Extratos Vegetais/farmacologia , Ribes , Prata/química , Tecnologia Farmacêutica/métodos , Animais , Sobrevivência Celular , Modelos Animais de Doenças , Lipopolissacarídeos/farmacologia , Masculino , Camundongos , Camundongos Endogâmicos BALB C , Tamanho da Partícula , Peroxidase/metabolismo , Extratos Vegetais/administração & dosagem , Células RAW 264.7
13.
Materials (Basel) ; 13(2)2020 Jan 08.
Artigo em Inglês | MEDLINE | ID: mdl-31936311

RESUMO

The rapid development of medicine has forced equally rapid progress in the field of pharmaceuticals. In connection with the expensive and time-consuming process of finding new drugs, great emphasis is put on the design and use of metal and metal oxides nanoparticles in nanomedicine. The main focus is on comprehensive presentation of both physicochemical properties and the possibilities of using, in particular, silver (Ag) and gold (Au) nanoparticles, as well as zinc oxide (ZnO) and titanium oxide (TiO2) nanoparticles as drug carriers and in the treatment of cancer. An important element of this subject is the possibility of occurrence of toxic effects of these nanoparticles. For this reason, possible mechanisms of toxic actions are presented, as well as methods used to reduce their toxicity to ensure the safety of drug carriers based on these nanostructures.

14.
Materials (Basel) ; 13(2)2020 Jan 12.
Artigo em Inglês | MEDLINE | ID: mdl-31940903

RESUMO

The rapid development of the production of materials containing metal nanoparticles and metal oxides is a potential risk to the environment. The degree of exposure of organisms to nanoparticles increases from year to year, and its effects are not fully known. This is due to the fact that the range of nanoparticle interactions on cells, tissues and the environment requires careful analysis. It is necessary to develop methods for testing the properties of nanomaterials and the mechanisms of their impact on individual cells as well as on entire organisms. The particular need to raise public awareness of the main sources of exposure to nanoparticles should also be highlighted. This paper presents the main sources and possible routes of exposure to metal nanoparticles and metal oxides. Key elements of research on the impact of nanoparticles on organisms, that is, in vitro tests, in vivo tests and methods of detection of nanoparticles in organisms, are presented.

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