Explore the vast range of titles available.

Versatile nature of copper oxide nanoparticles (CuO NPs) has made them an imperative nanomaterial being employed in nanomedicine. Various physical, chemical, and biological methodologies are in use for the preparation of CuO NPs. The physicochemical and biological properties of CuO NPs are primarily affected by their method of fabrication; therefore, selectivity of a synthetic technique is immensely important that makes these NPs appropriate for a specific biomedical application. The deliberate use of CuO NPs in biomedicine questions their biocompatible nature. For this reason, the present review has been designed to focus on the approaches employed for the synthesis of CuO NPs; their biomedical applications highlighting antimicrobial, anticancer, and antioxidant studies; and most importantly, the in vitro and in vivo toxicity associated with these NPs. This comprehensive overview of CuO NPs is unique and novel as it emphasizes on biomedical applications of CuO NPs along with its toxicological assessments which would be useful in providing core knowledge to researchers working in these domains for planning and conducting futuristic studies.Key Points• The recent methods for fabrication of CuO nanoparticles have been discussed with emphasis on green synthesis methods for different biomedical approaches.• Antibacterial, antioxidant, anticancer, antiparasitic, antidiabetic, and antiviral properties of CuO nanoparticles have been explained.• In vitro and in vivo toxicological studies of CuO nanoparticles exploited along with their respective mechanisms.

Although the toxicity of aluminum-based nanoparticles (Al 2 O 3 -NPs) in fish has been widely studied, strategies to mitigate their harmful effects remain limited. Moreover, the modulatory role of Astragalus membranaceus polysaccharides (APS) under this toxic stress is still poorly understood, despite the widespread presence of Al 2 O 3 -NPs in aquatic ecosystems and the need for effective mitigation strategies for sustainable aquaculture. In this study , Oreochromis niloticus was exposed to Al 2 O 3 -NPs (10 mg/L) with or without dietary APS (1.5 or 3 mg/kg) for four weeks. A total of 270 fish (initial weight = 25.28 ± 0.086 g) were randomly distributed into six triplicate groups ( n  = 15 per group) as control, APS (1.5 mg/kg–3 mg/kg), Al 2 O 3 -NPs, and two co-treated groups (Al 2 O 3 -NPs + APS). Al 2 O 3 -NPs exposure showed significant effects on growth performance compared to the control group ( P  < 0.05), as shown by the decrease in final weight (FW: -9.4%), weight gain (WG: − 21.4%), specific growth rate (SGR: -17.1%), along with an increase in feed conversion ratio (FCR: + 16.9%). Liver function was severely affected, as evidenced by an increase in ALT levels (+ 39%) and decrease in total protein (− 26.5%) and IgM levels (− 19.3%) ( P  < 0.05). In addition, the expression of antioxidant-related genes, such as CAT and SOD , was downregulated, while the expression of pro-inflammatory cytokines, such as TNF-β and IL-1β , as well as stress-related gene, such as MT , was upregulated in the liver and gills ( P  < 0.05). Histopathological examination showed noticeable degenerative and necrotic changes in the liver, kidney, muscle, gill, and spleen tissues. Co-treatment with APS, particularly at 3 mg/kg, significantly improved growth parameters (FW, 20.3% increase; WG, 53.1% increase; and SGR, 38.8% increase) ( P  < 0.05), ameliorated hepatic and renal histopathological changes, restored antioxidant gene expression and normalized inflammatory mediators compared with the Al 2 O 3 -NPs-exposed group. Compared with the Al 2 O 3 -NPs–exposed group, the survival rate increased by 5.3%, ALT levels decreased by 60.1%, while total protein and IgM levels increased by 29.6% and 8.9%, respectively. Overall, APS supplementation effectively mitigated Al 2 O 3 -NPs-induced toxicity in O. niloticus by regulating antioxidant capacity, suppressing inflammatory responses, and improving tissue structure, highlighting its potential as an eco-friendly functional food additive to protect fish health under nano-toxic stress .

Owing to recent advancements in nanotechnology, magnetic iron oxide nanoparticles (MNPs), particularly magnetite (Fe3O4) and maghemite (γ-Fe2O3), are currently widely employed in the field of medicine. These MNPs, characterized by their large specific surface area, potential for diverse functionalization, and magnetic properties, have found application in various medical domains, including tumor imaging (MRI), radiolabelling, internal radiotherapy, hyperthermia, gene therapy, drug delivery, and theranostics. However, ensuring the non-toxicity of MNPs when employed in medical practices is paramount. Thus, ongoing research endeavors are essential to comprehensively understand and address potential toxicological implications associated with their usage. This review aims to present the latest research and findings on assessing the potential toxicity of magnetic nanoparticles. It meticulously delineates the primary mechanisms of MNP toxicity at the cellular level, encompassing oxidative stress, genotoxic effects, disruption of the cytoskeleton, cell membrane perturbation, alterations in the cell cycle, dysregulation of gene expression, inflammatory response, disturbance in ion homeostasis, and interference with cell migration and mobility. Furthermore, the review expounds upon the potential impact of MNPs on various organs and systems, including the brain and nervous system, heart and circulatory system, liver, spleen, lymph nodes, skin, urinary, and reproductive systems.

Background Iron oxide nanoparticles have been approved by food and drug administration for clinical application as magnetic resonance imaging (MRI) and are considered to be a biocompatible material. Large iron oxide nanoparticles are usually used as transversal ( T 2 ) contrast agents to exhibit dark contrast in MRI. In contrast, ultrasmall iron oxide nanoparticles (USPIONs) (several nanometers) showed remarkable advantage in longitudinal ( T 1 )-weighted MRI due to the brighten effect. The study of the toxicity mainly focuses on particles with size of tens to hundreds of nanometers, while little is known about the toxicity of USPIONs. Results We fabricated Fe 3 O 4 nanoparticles with diameters of 2.3, 4.2, and 9.3 nm and evaluated their toxicity in mice by intravenous injection. The results indicate that ultrasmall iron oxide nanoparticles with small size (2.3 and 4.2 nm) were highly toxic and were lethal at a dosage of 100 mg/kg. In contrast, no obvious toxicity was observed for iron oxide nanoparticles with size of 9.3 nm. The toxicity of small nanoparticles (2.3 and 4.2 nm) could be reduced when the total dose was split into 4 doses with each interval for 5 min. To study the toxicology, we synthesized different-sized SiO 2 and gold nanoparticles. No significant toxicity was observed for ultrasmall SiO 2 and gold nanoparticles in the mice. Hence, the toxicity of the ultrasmall Fe 3 O 4 nanoparticles should be attributed to both the iron element and size. In the in vitro experiments, all the ultrasmall nanoparticles (< 5 nm) of Fe 3 O 4 , SiO 2 , and gold induced the generation of the reactive oxygen species (ROS) efficiently, while no obvious ROS was observed in larger nanoparticles groups. However, the ·OH was only detected in Fe 3 O 4 group instead of SiO 2 and gold groups. After intravenous injection, significantly elevated ·OH level was observed in heart, serum, and multiple organs. Among these organs, heart showed highest ·OH level due to the high distribution of ultrasmall Fe 3 O 4 nanoparticles, leading to the acute cardiac failure and death. Conclusion Ultrasmall Fe 3 O 4 nanoparticles (2.3 and 4.2 nm) showed high toxicity in vivo due to the distinctive capability in inducing the generation of ·OH in multiple organs, especially in heart. The toxicity was related to both the iron element and size. These findings provide novel insight into the toxicology of ultrasmall Fe 3 O 4 nanoparticles, and also highlight the need of comprehensive evaluation for their clinic application. Graphical Abstract

In recent years, research on silver nanoparticles (AgNPs) has attracted considerable interest among scientists because of, among other things, their alternative application to well-known medical agents with antibacterial properties. The size of the silver nanoparticles ranges from 1 to 100 nm. In this paper, we review the progress of research on AgNPs with respect to the synthesis, applications, and toxicological safety of AgNPs, and the issue of in vivo and in vitro research on silver nanoparticles. AgNPs’ synthesis methods include physical, chemical, and biological routes, as well as “green synthesis”. The content of this article covers issues related to the disadvantages of physical and chemical methods, which are expensive and can also have toxicity. This review pays special attention to AgNP biosafety concerns, such as potential toxicity to cells, tissues, and organs.

With the vigorous development of nanometer-sized materials, nanoproducts are becoming widely used in all aspects of life. In medicine, nanoparticles (NPs) can be used as nanoscopic drug carriers and for nanoimaging technologies. Thus, substantial attention has been paid to the potential risks of NPs. Previous studies have shown that numerous types of NPs are able to pass certain biological barriers and exert toxic effects on crucial organs, such as the brain, liver, and kidney. Only recently, attention has been directed toward the reproductive toxicity of nanomaterials. NPs can pass through the blood-testis barrier, placental barrier, and epithelial barrier, which protect reproductive tissues, and then accumulate in reproductive organs. NP accumulation damages organs (testis, epididymis, ovary, and uterus) by destroying Sertoli cells, Leydig cells, and germ cells, causing reproductive organ dysfunction that adversely affects sperm quality, quantity, morphology, and motility or reduces the number of mature oocytes and disrupts primary and secondary follicular development. In addition, NPs can disrupt the levels of secreted hormones, causing changes in sexual behavior. However, the current review primarily examines toxicological phenomena. The molecular mechanisms involved in NP toxicity to the reproductive system are not fully understood, but possible mechanisms include oxidative stress, apoptosis, inflammation, and genotoxicity. Previous studies have shown that NPs can increase inflammation, oxidative stress, and apoptosis and induce ROS, causing damage at the molecular and genetic levels which results in cytotoxicity. This review provides an understanding of the applications and toxicological effects of NPs on the reproductive system.

Accurate in vitro assessment of nanoparticle cytotoxicity requires a careful selection of the test systems. Due to high adsorption capacity and optical activity, engineered nanoparticles are highly potential in influencing classical cytotoxicity assays. Here, four common in vitro assays for oxidative stress, cell viability, cell death and inflammatory cytokine production (DCF, MTT, LDH and IL-8 ELISA) were assessed for validity using 24 well-characterized engineered nanoparticles. For all nanoparticles, the possible interference with the optical detection methods, the ability to convert the substrates, the influence on enzymatic activity and the potential to bind proinflammatory cytokines were analyzed in detail. Results varied considerably depending on the assay system used. All nanoparticles tested were found to interfere with the optical measurement at concentrations of 50 μg cm −2 and above when DCF, MTT and LDH assays were performed. Except for Carbon Black, particle interference could be prevented by altering assay protocols and lowering particle concentrations to 10 μg cm −2 . Carbon Black was also found to oxidize H 2 DCF-DA in a cell-free system, whereas only ZnO nanoparticles significantly decreased LDH activity. A dramatic loss of immunoreactive IL-8 was observed for only one of the three TiO 2 particle types tested. Our results demonstrate that engineered nanoparticles interfere with classic cytotoxicity assays in a highly concentration-, particle- and assay-specific manner. These findings strongly suggest that each in vitro test system has to be evaluated for each single nanoparticle type to accurately assess the nanoparticle toxicity.

With the rapid evolution of nanotechnology, magnetic iron oxide nanoparticles (MNPs)—primarily Fe3O4 and γ-Fe2O3—have gained prominence in biomedicine. Their extensive specific surface area, tunable surface functionalities, and intrinsic magnetic characteristics render them highly versatile for diverse clinical applications, including tumor visualization through Magnetic Resonance Imaging (MRI), radiolabeling, targeted radiotherapy, hyperthermia, gene transfer, drug delivery, Magnetic Particle Imaging (MPI), magnetic blood filtration and theranostic strategies. Nevertheless, ensuring the biocompatibility and non-toxicity of these nanostructures remains a fundamental prerequisite for their medical implementation. Hence, it is essential to continuously refine our understanding of MNP-related toxicity and pursue comprehensive research on this front. This article consolidates up-to-date insights into the evaluation of MNPs’ toxicological profiles, emphasizing the influence of physicochemical properties such as morphology, surface modifications, and electrostatic characteristics, along with operational factors like dosage and administration routes. Traditional toxicity testing strategies, including in vitro assays as first-line screening tools, together with standard ex vivo and in vivo models, are discussed. Special attention is given to the emerging role of New Approach Methodologies (NAMs), such as organoid formation, 3D bioprinting, in ovo chicken embryo assays, and image cytometry. These techniques offer ethical, human-relevant, and informative alternatives to animal testing, supporting more predictive and translationally relevant toxicity assessment of MNPs. Taken together, the integration of conventional assays with innovative NAMs, alongside careful consideration of physicochemical and operational factors, is essential to translate the laboratory promise of MNPs into safe and clinically effective nanomedicines.

In recent years, the extensive exploration of Gold Nanoparticles (AuNPs) has captivated the scientific community due to their versatile applications across various industries. With sizes typically ranging from 1 to 100 nm, AuNPs have emerged as promising entities for innovative technologies. This article comprehensively reviews recent advancements in AuNPs research, encompassing synthesis methodologies, diverse applications, and crucial insights into their toxicological profiles. Synthesis techniques for AuNPs span physical, chemical, and biological routes, focusing on eco-friendly “green synthesis” approaches. A critical examination of physical and chemical methods reveals their limitations, including high costs and the potential toxicity associated with using chemicals. Moreover, this article investigates the biosafety implications of AuNPs, shedding light on their potential toxic effects on cellular, tissue, and organ levels. By synthesizing key findings, this review underscores the pressing need for a thorough understanding of AuNPs toxicities, providing essential insights for safety assessment and advancing green toxicology principles.