Search Results (145)

Background/Objectives. This manuscript presents an overview of advances in oncological radiotherapy as an effective treatment method for cancerous tumors, focusing on mechanisms of action within metabolite–antimetabolite systems. The urgency of this topic is underscored by the fact that cancer remains one of the leading causes of death worldwide: as of 2022, approximately 20 million new cases were diagnosed globally, accounting for about 0.25% of the total population. Given prognostic models predicting a steady increase in cancer incidence to 35 million cases by 2050, there is an urgent need for the latest developments in physics, chemistry, molecular biology, pharmacy, and strict adherence to oncological vigilance. The purpose of this work is to demonstrate the relationship between the nature and mechanisms of past diagnostic and therapeutic oncology approaches, their current improvements, and future prospects. Particular emphasis is placed on isotope technologies in the production of therapeutic nuclides, focusing on the mechanisms of formation of simple and complex theranostic compounds and their classification according to target specificity. Methods. The methodology involved searching, selecting, and analyzing information from PubMed, Scopus, and Web of Science databases, as well as from available official online sources over the past 20 years. The search was structured around the structure–mechanism–effect relationship of active pharmaceutical ingredients (APIs). The manuscript, including graphic materials, was prepared using a narrative synthesis method. Results. The results present a sequential analysis of materials related to isotope technology, particularly nucleus stability and instability. An explanation of theranostic principles enabled a detailed description of the action mechanisms of radiopharmaceuticals on various receptors within the metabolite–antimetabolite system using specific drug models. Attention is also given to radioactive nanotheranostics, exemplified by the mechanisms of action of radioactive nanoparticles such as Tc-99m, AuNPs, wwAgNPs, FeNPs, and others. Conclusions. Radiotheranostics, which combines the diagnostic properties of unstable nuclei with therapeutic effects, serves as an effective adjunctive and/or independent method for treating cancer patients. Despite the emergence of resistance to both chemotherapy and radiotherapy, existing nuclide resources provide protection against subsequent tumor metastasis. However, given the unfavorable cancer incidence prognosis over the next 25 years, the development of “preventive” drugs is recommended. Progress in this area will be facilitated by modern medical knowledge and a deeper understanding of ligand–receptor interactions to trigger apoptosis in rapidly proliferating cells. Full article

Silver nanoparticles (AgNPs), iron oxide nanoparticles (Fe₂O₄NPs), and multiwalled carbon nanotubes (MWCNTs) are widely used in various applications, such as biomedicine, environmental remediation, and agriculture. In addition, these nanomaterials can affect the production of bioactive compounds in plants that have pharmacological activities. In the current study, the in vitro plant cultures of Chinese lobelia (Lobelia chinensis Lour.) were established in MS medium and treated with 0, 12.5, 25, 37.5, and 50 mg L⁻¹ AgNPs or Fe₂O₄NPs, or MWCNTs. Initially, plants were grown for four weeks without any elicitors, and after that, the cultures were treated with nano-elicitors for one week. After five weeks, the effects of nano-elicitors were estimated on growth, total phenolic, flavonoids, polyacetylenes, and ABTS/DPPH/FRAP antioxidant activity was investigated. The results showed that lower levels of AgNPs (25 mg L⁻¹), Fe₂O₄NPs (25 mg L⁻¹), and MWCNTs (12.5 mg L⁻¹) favored the accumulation of fresh and dry biomass. Whereas, 37.5 mg L⁻¹ AgNPs, 25 mg L⁻¹ Fe₂O₄NPs, and 37.5 mg L⁻¹ MWCNTs enhanced the accumulation of total phenolics, flavonoids, specific phenolic compounds including chlorogenic acid, catechin, phloretic acid, coumaric acid, salicylic acid, naringin, myricetin, linarin, and polyacetylenes viz. lobetylonin and lobetyolin in higher concentrations. The plant extracts elicited by nanomaterials also depicted very good antioxidant activities according to ABTS, DPPH, and FRAP assays. These results suggest that specific nanomaterials, and at specific levels, could be used for the production of bioactive compounds from shoot cultures of Chinese lobelia. Full article

The detection of Fe²⁺ in environmental water sources is critical due to its biological relevance and potential toxicity at elevated levels. Herein, we report a plasmon-driven catalytic sensing nanoplatform based on p-aminothiophenol (pATP)-functionalized silver nanoparticles (AgNPs) for the selective and sensitive detection of Fe²⁺. The nanoplatform exploits the inhibition of the plasmon-driven catalytic conversion of pATP to 4,4-dimercaptoazobenzene (DMAB), monitored via surface-enhanced Raman scattering (SERS) spectroscopy. The catalytic efficiency was quantified by the intensity ratio between the formed DMAB-specific Raman band and the common aromatic ring vibration band of pATP and DMAB. This ratio decreased proportionally with increasing Fe²⁺ concentration over a range of 100 µM to 1.5 mM, with a calculated limit of detection of 39.7 µM. High selectivity was demonstrated against common metal ions, and excellent recovery rates (96.6–99.4%) were obtained in real water samples. Mechanistic insights, supported by chronopotentiometric measurements under light irradiation, revealed a competitive oxidation pathway in which Fe²⁺ preferentially consumes plasmon-generated hot holes over pATP. This mechanism clarifies the observed catalytic inhibition and supports the design of redox-responsive SERS sensors. The platform offers a rapid, low-cost, and portable solution for Fe²⁺ monitoring and holds promise for broader applications in detecting other redox-active analytes in complex environmental matrices. Full article

The purpose of current study was the green synthesis of bioactive silver nanoparticles (AgNPs) using Brevibacillus sp. MAHUQ-41 and the exploration of their role in controlling drug-resistant bacterial pathogens Listeria monocytogenes and Yersinia enterocolitica. The culture supernatant of strain MAHUQ-41 was employed for a simple and eco-friendly synthesis of biofunctional silver nanoparticles (AgNPs). The resulting nanoparticles were analyzed using several techniques, including UV–Visible spectroscopy, XRD, FE-TEM, FTIR, and DLS. The UV–Vis spectral analysis of the AgNPs synthesized via Brevibacillus sp. MAHUQ-41 revealed a prominent absorption peak at 400 nm. FE-TEM results confirmed spherical-shaped 15–60 nm sized nanoparticles. XRD results indicated that the synthesized AgNPs were crystalline in nature. The FTIR spectrum determined various functional groups on the surface of synthesized nanoparticles. Potent antibacterial properties were observed in green-synthesized AgNPs against tested pathogens. The MIC value of extracellular synthesized AgNPs for both pathogenic bacteria was 6.2 µg/mL, and the MBCs were 25.0 µg/mL and 12.5 µg/mL for L. monocytogenes and Y. enterocolitica, respectively. Treatment by synthesized AgNPs resulted in morphological alterations and structural damages in both L. monocytogenes and Y. enterocolitica. These alterations can interfere with regular cellular activities, potentially resulting in cell death. This study is the first to report the antimicrobial properties of silver nanoparticles synthesized using Brevibacillus sp. MAHUQ-41. The findings obtained in the present study supported the role of Brevibacillus sp. MAHUQ-41-mediated synthesized AgNPs in controlling drug-resistant bacterial pathogens L. monocytogenes and Y. enterocolitica. Full article

Bacterial infections are the primary cause of mastitis in dairy cattle. Fungal mastitis occurs in 1–12% of cases. Antibiotic therapy, the standard treatment for mastitis, has led to antibiotic-resistant bacteria, reducing treatment efficacy and increasing fungal mastitis occurrence. Antibiotics lack biocidal effects on fungi, which often exhibit resistance to antifungal agents. This study evaluated the antifungal properties of nanoparticles (NPs) against Candida albicans, Candida glabrata, Candida parapsilosis, Diutina rugosa var. rugosa, Diutina catenulata, and Diutina rugosa. Tested NPs included gold (AuNPs), silver (AgNPs), copper (CuNPs), iron with hydrophilic carbon coating (FeCNPs) (1.56–25 mg/L), and platinum (PtNPs) (0.625–10 mg/L), along with their complexes. Minimum inhibitory concentration (MIC) and minimum fungicidal concentration (MFC) at 0.75–25 mg/L for AuNPs, AgNPs, CuNPs, and FeCNPs and 0.313–10 mg/L for PtNPs, as well as fungal sensitivity to standard antifungals, were determined. Each strain showed different sensitivities depending on the NPs used and their concentrations. C. glabrata was the most resistant to nanoparticles, while D. catenulata was the most susceptible. PtNPs and FeCNPs showed no or weak biocidal properties. Some mycotic-resistant strains were sensitive to nanoparticles. This study indicates a high in vitro antifungal potential for the application of nanoparticles, especially AgCuNPs, as a new effective non-antibiotic agent for the prevention and control of mycotic mastitis in dairy cattle. Full article

Nanotechnology is emerging as an innovative and sustainable agricultural approach that minimizes environmental impacts by developing nanostructured materials to promote plant growth and combat plant-parasitic nematodes (PPNs). Plant-based nanoparticles (NPs) are attracting increasing attention as they are more environmentally friendly, economical and biocompatible compared to traditional chemical and physical synthesis methods. The ability of plants to reduce and stabilize metal ions and form NPs of specific size and morphology through their biochemical content offers great advantages for agricultural applications. Phytochemicals produced by plants enable the biological synthesis of metal and metal oxide NPs by acting as reducing agents and coating agents in NP synthesis. The effects of plant-based NPs in nematode control are based on mechanisms such as the disruption of the nematode cuticle, induction of oxidative stress and interference with parasite metabolism. Several plant species have been investigated for the synthesis of metal and metal oxide nanoparticles such as silver (Ag-NPs), nickel oxide (NiO-NPs), zinc oxide (ZnO-NPs), copper oxide (CuO-NPs) and iron (Fe-NPs). These biologically synthesized NPs show potent biological activity against important PPNs such as Meloidogyne spp., Pratylenchus spp. and Heterodera spp. The integration of plant-derived NPs into agricultural systems has significant potential for plant growth promotion, nematode suppression and soil health improvement. This review highlights their role in reducing environmental impact in agricultural applications by examining the sustainable synthesis processes of plant-based NPs. Full article

This study focuses on preparing and characterizing functionalized silver nanoparticle-based (Ag-F NPs) finishing agents for leather treatment. Ag-F NPs were synthesized and functionalized through a ligand exchange process with citric acid, enhancing their dispersion stability in aqueous media. The nanoparticles were incorporated into polyurethane- and nitroemulsion-based finishing formulations and applied to ovine and bovine leather via a spray coating process. Morphological (SEM, TEM), structural (XRD), thermal (TGA), and spectroscopic (FT-IR) analyses confirmed successful functionalization and uniform dispersion within the finishing layer. Leather samples treated with Ag-F NPs exhibited a significant improvement in antibacterial properties, with microbial growth reduction of up to 90% after 72 h. Additionally, accelerated aging tests demonstrated enhanced UV resistance, with a 30% lower color change (∆E) compared to control samples. The Ag-F NPs-based finishing layers also exhibited superior abrasion and micro-scratch resistance, maintaining a stable coefficient of friction over time. These findings demonstrate the potential of Ag-F NPs as multifunctional leather-finishing agents, making them highly suitable for applications in the automotive, footwear, and leather goods industries. Full article

Ammonia is one of the common inorganic pollutants in surface waters. It can come from a wide range of sources through the discharge of wastewater (industry, agriculture, and municipal waters). Catalytic ozonation reaction can efficiently remove ammonia nitrogen without introducing other pollutants and improve the nitrogen selectivity of reaction products by controlling the reaction conditions. Catalysts based on silver nanoparticles (Ag NPs) have shown excellent O₃ decomposition performance; therefore, they are promising catalysts for catalytic ammonia ozonation due to their high reactivity, stability, and selectivity to N₂. In this study, we synthesized well-defined silver nanoparticles (Ag NPs) using a modified alkaline polyol method and then dispersed them on solid oxide supports (Fe₃O₄, TiO₂, and WO₃). Before being deposited on the oxide support, the silver nanoparticles were characterized by X-ray diffraction (XRD), transmission electron microscopy (TEM), and UV-VIS spectroscopy. The obtained catalysts, Ag_Fe₃O₄, Ag_TiO₂, and Ag_WO₃ were characterized using X-ray diffraction (XRD), scanning electron microscopy (SEM), BET surface area analysis, UV-VIS spectroscopy, temperature-programmed reduction (H₂-TPR), and temperature-programmed desorption (TPD) of CO₂ and NH₃. It has been demonstrated that the nature of the support significantly influences the physicochemical properties of the catalysts, as well as their catalytic performance in ammonia ozonation reaction. Full article

Mine tailings are a byproduct of mineral extraction and often pose an environmental challenge due to the contamination of soil and water bodies with dissolved metals. However, this type of waste offers the opportunity for the recovery of valuable metals such as silver (Ag). In the present investigation, an integral analysis of a sample of tailings was carried out, addressing granulometry, elemental composition, neutralization potential (NP), and acid potential (AP), as well as mineralogy, for the dissolution of silver from this type of waste. For this purpose, thiourea (CH₄N₂S) was used as a leaching agent due to its low toxicity, and potassium oxalate (K₂C₂O₄) was used as an organic additive to improve the leaching of the silver phases (argentite and polybasite) present in the tailings. The effects of CH₄N₂S and K₂C₂O₄ concentrations, temperature, and pH on the leaching efficiency of silver (Ag), copper (Cu), iron (Fe), and arsenic (As) were systematically studied. The results revealed that the maximum silver dissolution rate reached 90.75% under optimal conditions: 0.2 M L⁻¹ of thiourea and 0.2 M L⁻¹ of potassium oxalate, at 35 °C and a pH of 2. Full article

In recent years, nanomaterials have gained special attention for removing contaminants from wastewater. Nanoparticles (NPs), such as carbon-based materials and metal oxides, exhibit exceptional adsorption capacity and antimicrobial properties for wastewater treatment. Their unique properties, including reactivity, high surface area, and tunable surface functionalities, make them highly effective adsorbents. They can remove contaminants such as organics, inorganics, pharmaceuticals, medicine, and dyes by adsorption mechanisms. In this review, the effectiveness of different types of carbon-based NPs, including carbon nanotubes (CNTs), graphene-based nanoparticles (GNPs), carbon quantum dots (CQDs), carbon nanofibers (CNFs), and carbon nanospheres (CNSs), and metal oxides, including copper oxide (CuO), zinc oxide (ZnO), iron oxide (Fe₂O₃), titanium oxide (TiO₂), and silver oxide (Ag₂O), in the removal of different contaminants from wastewater has been comprehensively evaluated. In addition, their synthesis methods, such as physical, chemical, and biological, have been described. Based on the findings, CNPs can remove 75 to 90% of pollutants within two hours, while MONPs can remove 60% to 99% of dye in 150 min, except iron oxide NPs. For future studies, the integration of NPs into existing treatment systems and the development of novel nanomaterials are recommended. Hence, the potential of NPs is promising, but challenges related to their environmental impact and their toxicity must be considered. Full article

A green and cost-effective sonochemical synthetic method was followed for coating silver-modified copper oxide (Ag-CuO) nanoparticles (NPs) on disposable surgical mask. The NP-coated masks were systematically characterized using XRD and FT-IR for understanding the structural and surface functionalities. In addition, the field emission scanning electron microscopy (FE-SEM) analysis showed the homogeneous coating of Ag-CuO NPs over the mask fibers. The average particle size of Ag-CuO was found to be ~70 nm. The NP-coated masks are useful to combat a broad range of bacterial species by taking the unique advantage of the synergistic effect of Ag and metal oxide (CuO and ZnO) NPs for the generation of reactive oxygen species (ROS). Zone of inhibition (ZoI) studies demonstrated antibacterial activity against both Gram-positive S. aureus and Gram-negative E. coli bacteria, probably due to the elevated production of ROS by the defect structure of the Ag-modified metal oxide NPs. The material was found to be effective against both airborne and soil-borne bacteria. We repeat that this paper deals only with the killing effect of the nanoparticles (Ag-modified CuO) on bacteria, and no studies on viral species are performed. Full article

Silver nanoparticles are one of the most commonly used forms of silver (Ag) in nanotechnology applications due to their antibacterial properties and electrical and thermal resistance. The increasing production and use of products containing nanoparticles has led to their release into and contamination of soil and water. This review summarizes the literature on the fate, behavior (adsorption/desorption, precipitation/oxidative dissolution, transformation), and transport/mobility of Ag forms in soils (Ag⁺ ions and Ag nanoparticles—AgNPs). The behavior of Ag⁺/AgNPs in soil is a complex process. It depends on many factors, including the characteristics of the Ag forms (ions, nanoparticle size, ligand type used for coating, surface charge, initial Ag concentration), the soil properties (organic matter and clay mineral content, textural properties, point of zero charge, cation exchange capacity, surface functional groups), and the solute properties (pH–Eh, ionic strength, cation type, oxygen content). The binding of Ag⁺ and AgNPs is significantly positively correlated with Al/Fe/Mn oxide and SOM content and depends on the surface charge of the minerals and CEC, which controls adsorption processes. Very important parameters to consider are the pH and Eh of the solution, which determine the durability of the ligands, the aggregation rate and the oxidation process of AgNPs, as well as the presence of sulfide and chloride and the Cl/Ag ratio, which determine the stability/mobility of Ag. Since AgNPs can be oxidized to Ag⁺ ions during their life cycle, it is necessary to consider the behavior of both forms of Ag in soils. Understanding the transport and behavior of Ag in soil is essential for the environmental risk assessment and management of wastes containing Ag. Full article

The biosynthesis of silver nanoparticles (AgNPs) presents an innovative and sustainable approach in nanotechnology with promising applications in fields such as medicine, food safety, and pharmacology. In this study, AgNPs were successfully synthesized using the probiotic strain Lacticaseibacillus rhamnosus (BCRC16000), addressing challenges related to stability, biocompatibility, and scalability that are common in conventional nanoparticle production methods. The formation of AgNPs was indicated by a color change from yellow to brown, and UV–visible spectrophotometry confirmed their presence with a characteristic absorption peak at 443 nm. Furthermore, Fourier transform infrared (FTIR) spectroscopy revealed the involvement of biomolecules in reducing silver ions, which suggests their role in stabilizing the nanoparticles. In addition, field emission scanning electron microscopy (FE-SEM) showed significant morphological and structural changes. At the same time, dynamic light scattering (DLS) and zeta potential analyses provided valuable insights such as average size (199.7 nm), distribution, and stability, reporting a polydispersity index of 0.239 and a surface charge of −36.3 mV. Notably, the AgNPs demonstrated strong antibacterial activity and photocatalytic efficiency, underscoring their potential for environmental and biomedical applications. Therefore, this study highlights the effectiveness of Lacticaseibacillus rhamnosus in the biosynthesis of AgNPs, offering valuable antibacterial and photocatalytic properties with significant industrial and scientific implications. Full article

The applications of nanotechnology in the field of water treatment are rapidly expanding and have harvested significant attention from researchers, governments, and industries across the globe. This great interest stems from the numerous benefits, properties, and capabilities that nanotechnology offers in addressing the ever-growing challenges related to water quality, availability, and sustainability. This review paper extensively studies the applications of several nanomaterials including: graphene and its derivative-based adsorbents, CNTs, TiO₂ NPs, ZnO NPs, Ag NPs, Fe NPs, and membrane-based nanomaterials in the purification of drinking water. This, it is hoped, will provide the water treatment sector with efficient materials that can be applied successfully in the water purification process to help in addressing the worldwide water scarcity issue. Full article

In this paper, we report a simple yet efficient method for rapid and high-performance SERS substrate fabrication by a combination of cold plasma and laser treatment. Our analysis reveals that cold plasma pre-treatment significantly reduced surface roughness, transforming 200 nm spikes into an almost perfectly uniform surface, while enhancing the substrate’s surface energy by lowering the water contact angle from 59° to 0°, all achieved within just 30 s of 0.9-mW plasma treatment, while 15-min green-laser treatment facilitated more uniform deposition of AuNPs across the entire treated area, effectively creating the SERS substrates. The combined treatments result in enhancement of the Raman intensity (11 times) and consistency over the whole area of the SERS substrates, and their reusability (up to 10 times). The fabricated SERS substrates exhibit a significant enhancement factor of approximately 3 × 10⁸ with R6G, allowing detection down to a concentration of 10⁻¹² M. We demonstrate the application of these SERS substrates by detecting amoxicillin—an antibiotic used worldwide to treat a diversity of bacterial infections—in a dynamic expanded linear range of seven orders (from 10⁻³ to 10⁻⁹ M) with high reliability (R² = 0.98), and a detection limit of 9 × 10⁻¹⁰ M. Our approach to high-performance SERS substrate fabrication holds potential for further expansion to other metallic NPs like Ag, or magnetic NPs (Fe₃O₄). Full article