Zerovalent Fe, Co and Ni nanoparticle toxicity evaluated on SKOV-3 and U87 cell lines

Biological activity of silver nanoparticles synthesized using viticultural waste

This research paper presents a novel approach to the green synthesis of silver nanoparticles (AgNPs) using viticultural waste, allowing to obtain NP dispersions with distinct properties and morphologies (monodisperse and polydisperse AgNPs, referred to as mAgNPs and pAgNPs) and to compare their biological activities. Our synthesis method utilized the ethanolic extract of Vitis vinifera pruning residues, resulting in the production of mAgNPs and pAgNPs with average sizes of 12 ± 5 nm and 19 ± 14 nm, respectively. Both these AgNPs preparations demonstrated an exceptional stability in terms of size distribution, which was maintained for one year. Antimicrobial testing revealed that both types of AgNPs inhibited either the growth of planktonic cells or the metabolic activity of biofilm sessile cells in Gram-negative bacteria and yeasts. No comparable activity was found towards Gram-positives. Overall, pAgNPs exhibited a higher antimicrobial efficacy compared to their monodisperse counterparts, suggesting that their size and shape may provide a broader spectrum of interactions with target cells. Both AgNP preparations showed no cytotoxicity towards a human keratinocyte cell line. Furthermore, in vivo tests using a silkworm animal model indicated the biocompatibility of the phytosynthesized AgNPs, as they had no adverse effects on insect larvae viability. These findings emphasize the potential of targeted AgNPs synthesized from viticultural waste as environmentally friendly antimicrobial agents with minimal impact on higher organisms.

Nanoscale coordination polymer Fe-DMY downregulating Poldip2-Nox4-H2O2 pathway and alleviating diabetic retinopathy

Diabetic retinopathy (DR) is a prevalent microvascular complication of diabetes and the leading cause of blindness and severe visual impairment in adults. The high levels of glucose trigger multiple intracellular oxidative stress pathways, such as POLDIP2, resulting in excessive reactive oxygen species (ROS) production and increased expression of vascular cell adhesion molecule-1 (VCAM-1), hypoxia-inducible factor 1α (HIF-1α), and vascular endothelial growth factor (VEGF), causing microvascular dysfunction. Dihydromyricetin (DMY) is a natural flavonoid small molecule antioxidant. However, it exhibits poor solubility in physiological environments, has a short half-life in vivo, and has low oral bioavailability. In this study, we present, for the first time, the synthesis of ultra-small Fe-DMY nano-coordinated polymer particles (Fe-DMY NCPs), formed by combining DMY with low-toxicity iron ions. In vitro and in vivo experiments confirm that Fe-DMY NCPs alleviate oxidative stress-induced damage to vascular endothelial cells by high glucose, scavenge excess ROS, and improve pathological features of DR, such as retinal vascular leakage and neovascularization. Mechanistic validation indicates that Fe-DMY NCPs can inhibit the activation of the Poldip2-Nox4-H2O2 signaling pathway and downregulate vital vascular function indicators such as VCAM-1, HIF-1α, and VEGF. These findings suggest that Fe-DMY NCPs could serve as a safe and effective antioxidant and microangio-protective agent, with the potential as a novel multimeric drug for DR therapy.

Iron Oxide Nanoparticles with and without Cobalt Functionalization Provoke Changes in the Transcription Profile via Epigenetic Modulation of Enhancer Activity

Despite the progress in the field of nanotoxicology, much about the cellular mechanisms that mediate the adverse effects of nanoparticles (NPs) and, in particular, the possible role of epigenetics in nanotoxicity, remains to be clarified. Therefore, we studied the changes occurring in the genome-wide distribution of H3K27ac, H3K4me1, H3K9me2, and H3K27me3 histone modifications and compared them with the transcriptome after exposing NIH3T3 cells to iron-based magnetic NPs (i.e., Fe2O3 and Fe2O3@Co NPs). We found that the transcription response is mainly due to changes in the genomic distribution of H3K27ac that can modulate the activity of enhancers. We propose that alteration of the epigenetic landscape is a key mechanism in defining the gene expression program changes resulting in nanotoxicity. With this approach, it is possible to construct a data set of genomic regions that could be useful for defining toxicity in a manner that is more comprehensive than what is possible with the present toxicology assays.

Iron Nanoparticles Open Up New Directions for Promoting Healing in Chronic Wounds in the Context of Bacterial Infection

Metal nanoparticles play an outstanding role in the field of wound healing due to their excellent properties, and the significance of iron, one of the most widely used metals globally, cannot be overlooked. The purpose of this review is to determine the importance of iron nanoparticles in wound-healing dressings. Prolonged, poorly healing wounds may induce infections; wound infections are a major cause of chronic wound formation. The primary components of iron nanoparticles are iron oxide nanoparticles, which promote wound healing by being antibacterial, releasing metal ions, and overcoming bacterial resistance. The diameter of iron oxide nanoparticles typically ranges between 1 and 100 nm. Magnetic nanoparticles with a diameter of less than 30 nm are superparamagnetic and are referred to as superparamagnetic iron oxide nanoparticles. This subset of iron oxide nanoparticles can use an external magnetic field for novel functions such as magnetization and functionalization. Iron nanoparticles can serve clinical purposes not only to enhance wound healing through the aforementioned means but also to ameliorate anemia and glucose irregularities, capitalizing on iron's properties. Iron nanoparticles positively impact the healing process of chronic wounds, potentially extending beyond wound management.

Energy Transfer from Magnetic Iron Oxide Nanoparticles: Implications for Magnetic Hyperthermia

Magnetic iron oxide nanoparticles (IONPs) have gained momentum in the field of biomedical applications. They can be remotely heated via alternating magnetic fields, and such heat can be transferred from the IONPs to the local environment. However, the microscopic mechanism of heat transfer is still debated. By X-ray total scattering experiments and first-principles simulations, we show how such heat transfer can occur. After establishing structural and microstructural properties of the maghemite phase of the IONPs, we built a maghemite model functionalized with aminoalkoxysilane, a molecule used to anchor (bio)molecules to oxide surfaces. By a linear response theory approach, we reveal that a resonance mechanism is responsible for the heat transfer from the IONPs to the surroundings. Heat transfer occurs not only via covalent linkages with the IONP but also through the solvent hydrogen-bond network. This result may pave the way to exploit the directional control of the heat flow from the IONPs to the anchored molecules-i.e., antibiotics, therapeutics, and enzymes-for their activation or release in a broader range of medical and industrial applications.

Engineered nanoparticles toxicity on adipose tissue derived mesenchymal stem cells: A preliminary investigation

Nanoscience and nanotechnologies have recently gained importance in several fields, such as industry and medicine. A big issue of the increasing application of nanomaterials is the poor literature regarding their potential toxicity in humans and animals. Recently, adult stem cells have been proposed as putative targets of nanoparticles (NPs). This study aims to investigate the effects of zerovalent-metallic NPs on isolated and amplified equine Adipose tissue derived Mesenchymal Stem Cells (eAdMSCs). Cells were treated with Cobalt (Co-), Iron (Fe-), and Nickel (Ni-) nanoparticles (NPs) at different concentrations and were characterized for the cytotoxic and genotoxic effects of exposure. Treatment with NPs resulted in reduced cell viability and proliferative capability in comparison with untreated cells. However, this did not influence eAdMSCs potency, as treated cells were able to differentiate towards the adipogenic and osteogenic lineages. Ni- and Fe-NPs showed cytoplasmic localization, while Co-NPs entered the nucleus and mitochondria, suggesting a potential genotoxic activity. Regarding p53 expression, it was enhanced in the first 48 h after treatments, with a drastic reduction of expression within 72 h. Higher p53 expression was reported in the case of Co-NP treatment, suggesting the tumorigenic potential of these NPs. Telomerase activity was enhanced by Fe- and Ni-NP treatments in a concentration- and time-dependent way. This was not true for Co-NP treated samples, suggesting a reduced replicative capacity of eAdMSCs upon Co-NP exposure. The present study is a preliminary investigation of the influence exerted by NPs on eAdMSC physiological activity in terms of cytotoxic and genotoxic effects. The present results revealed eAdMSC physiology to be strongly influenced by NPs in a dose-, time- and NP-dependent way.

Leachate treatment potential of nanomaterial based assemblies: a systematic review on recent development

Rapid development of the population has brought about a serious problem of waste generation and management. Open dumping and land filling are two of the preferred options for waste management and treatment. As a consequence of this, the accumulation of leachates has become one of the concerns for environmental sustainability. In this regard, various treatment methodologies have been developed in recent decades. Among them, the nanomaterial-based approaches are the emerging ones in the current scenario due to their various unique properties. Furthermore, nanomaterial-based assemblies (i.e., nanomaterials combined with microbes, chemical catalysts, enzymes, and so on) have been introduced as a novel modification for leachate treatment. This work, therefore, has been dedicated to comprehensively reviewing all nanomaterial based leachate treatment techniques. In this regard, the first part of this review will discuss the nano catalyst, nano adsorbent along with their synthesis and mechanistic view of pollutant removal potential. In the second part, the nanomaterial-based microbial conjugates applied in the leachate treatments have been discussed. Apart from this, various other nanomaterial-based methods have been discussed in the third part of the review. Hence this review is providing an insight of all the recent developments pertaining to the nano material based leachate treatment techniques.

Assessing the Biocompatibility of Multi-Anchored Glycoconjugate Functionalized Iron Oxide Nanoparticles in a Normal Human Colon Cell Line CCD-18Co

We have previously demonstrated that iron oxide nanoparticles with dopamine-anchored heterobifunctional polyethylene oxide (PEO) polymer, namely PEO-IONPs, and bio-functionalized with sialic-acid specific glycoconjugate moiety (Neu5Ac(α2-3)Gal(β1-4)-Glcβ-sp), namely GM3-IONPs, can be effectively used as antibacterial agents against target Escherichia coli. In this study, we evaluated the biocompatibility of PEO-IONPs and GM3-IONPs in a normal human colon cell line CCD-18Co via measuring cell proliferation, membrane integrity, and intracellular adenosine triphosphate (ATP), glutathione GSH, dihydrorhodamine (DHR) 123, and caspase 3/7 levels. PEO-IONPs caused a significant decrease in cell viability at concentrations above 100 μg/mL whereas GM3-IONPs did not cause a significant decrease in cell viability even at the highest dose of 500 μg/mL. The ATP synthase activity of CCD-18Co was significantly diminished in the presence of PEO-IONPs but not GM3-IONPs. PEO-IONPs also compromised the membrane integrity of CCD-18Co. In contrast, cells exposed to GM3-IONPs showed significantly different cell morphology, but with no apparent membrane damage. The interaction of PEO-IONPs or GM3-IONPs with CCD-18Co resulted in a substantial decrease in the intracellular GSH levels in a time- and concentration-dependent manner. Conversely, levels of DHR-123 increased with IONP concentrations. Levels of caspase 3/7 proteins were found to be significantly elevated in cells exposed to PEO-IONPs. Based on the results, we assume GM3-IONPs to be biocompatible with CCD-18Co and could be further evaluated for selective killing of pathogens in vivo.

Recovery ability of human adipose stem cells exposed to cobalt nanoparticles: outcome of dissolution

Aim: To demonstrate that cobalt nanoparticles doses are safe for use in humans and to understand the consequences of the particulate effects, which may persist inside the cells. Materials & methods: Human adipose stem cells were used. We evaluated cell recovery by viability test, morphology and ultrastructure using electronic and optical microscopy, while gene expression was assessed utilizing real-time PCR. Results: After exposure, most stem cells recovered their normal function. Co₃O₄-nanoparticles remained inside the cell for the entirety of the considered time. A slight modification of gene expression was observed in the exposed cells. Conclusion: After exposure to 100 M cobalt nanoparticles, most cells returned to normal function. Nanoparticle toxicity was due to ions released by dissolution as well as from the nanoparticles themselves.

Redox interactions and genotoxicity of metal-based nanoparticles: A comprehensive review

Nanotechnology is a growing science that may provide several new applications for medicine, food preservation, diagnostic technologies, and sanitation. Despite its beneficial applications, there are several questions related to the safety of nanomaterials for human use. The development of nanotechnology is associated with some concerns because of the increased risk of carcinogenesis following exposure to nanomaterials. The increased levels of reactive oxygen species (ROS) that are due to exposure to nanoparticles (NPs) are primarily responsible for the genotoxicity of metal NPs. Not all, but most metal NPs are able to directly produce free radicals through the release of metal ions and through interactions with water molecules. Furthermore, the increased production of free radicals and the cell death caused by metal NPs can stimulate reduction/oxidation (redox) reactions, leading to the continuous endogenous production of ROS in a positive feedback loop. The overexpression of inflammatory mediators, such as NF-kB and STATs, the mitochondrial malfunction and the increased intracellular calcium levels mediate the chronic oxidative stress that occurs after exposure to metal NPs. In this paper, we review the genotoxicity of different types of metal NPs and the redox mechanisms that amplify the toxicity of these NPs.

Potential of Nanomaterial Applications in Dietary Supplements and Foods for Special Medical Purposes

Dietary supplements and foods for special medical purposes are special medical products classified according to the legal basis. They are regulated, for example, by the European Food Safety Authority and the U.S. Food and Drug Administration, as well as by various national regulations issued most frequently by the Ministry of Health and/or the Ministry of Agriculture of particular countries around the world. They constitute a concentrated source of vitamins, minerals, polyunsaturated fatty acids and antioxidants or other compounds with a nutritional or physiological effect contained in the food/feed, alone or in combination, intended for direct consumption in small measured amounts. As nanotechnology provides "a new dimension" accompanied with new or modified properties conferred to many current materials, it is widely used for the production of a new generation of drug formulations, and it is also used in the food industry and even in various types of nutritional supplements. These nanoformulations of supplements are being prepared especially with the purpose to improve bioavailability, protect active ingredients against degradation, or reduce side effects. This contribution comprehensively summarizes the current state of the research focused on nanoformulated human and veterinary dietary supplements, nutraceuticals, and functional foods for special medical purposes, their particular applications in various food products and drinks as well as the most important related guidelines, regulations and directives.

Magnetic Nanoconjugated Teicoplanin: A Novel Tool for Bacterial Infection Site Targeting

Nanoconjugated antibiotics can be regarded as next-generation drugs as they possess remarkable potential to overcome multidrug resistance in pathogenic bacteria. Iron oxide nanoparticles (IONPs) have been extensively used in the biomedical field because of their biocompatibility and magnetic properties. More recently, IONPs have been investigated as potential nanocarriers for antibiotics to be magnetically directed to/recovered from infection sites. Here, we conjugated the “last-resort” glycopeptide antibiotic teicoplanin to IONPs after surface functionalization with (3-aminopropyl) triethoxysilane (APTES). Classical microbiological methods and fluorescence and electron microscopy analysis were used to compare antimicrobial activity and surface interactions of naked IONPs, amino-functionalized NPs (NP-APTES), and nanoconjugated teicoplanin (NP-TEICO) with non-conjugated teicoplanin. As bacterial models, differently resistant strains of three Gram-positive bacteria (Staphylococcus aureus, Enterococcus faecalis, and Bacillus subtilis) and a Gram-negative representative (Escherichia coli) were used. The results indicated that teicoplanin conjugation conferred a valuable and prolonged antimicrobial activity to IONPs toward Gram-positive bacteria. No antimicrobial activity was detected using NP-TEICO toward the Gram-negative E. coli. Although IONPs and NP-APTES showed only insignificant antimicrobial activity in comparison to NP-TEICO, our data indicate that they might establish diverse interaction patterns at bacterial surfaces. Sensitivity of bacteria to NPs varied according to the surface provided by the bacteria and it was species specific. In addition, conjugation of teicoplanin improved the cytocompatibility of IONPs toward two human cell lines. Finally, NP-TEICO inhibited the formation of S. aureus biofilm, conserving the activity of non-conjugated teicoplanin versus planktonic cells and improving it toward adherent cells.

Iron oxide nanoparticles can cross plasma membranes

Iron deficiency is a major global public health problem despite decades of efforts with iron supplementation and fortification. The issue lies on the poor tolerability of the standard of care soluble iron salts, leading to non-compliance and ineffective correction of iron-deficiency anaemia. Iron nanoformulations have been proposed to fortify food and feed to address these issues. Since it was just postulated that some nanoparticles (NPs) might cross the plasma membrane also by a non-endocytotic pathway gaining direct access to the cytoplasm, we have studied iron NP uptake under this perspective. To this aim, we have used a recently tested protocol that has proven to be capable of following the cytoplasmic changes of iron concentration dynamics and we have demonstrated that iron oxide NPs, but not zerovalent iron NPs nor iron oxide NPs that were surrounded by a protein corona, can cross plasma membranes. By electrophysiology, we have also shown that a small and transient increase of membrane conductance parallels NP crossing of plasma membrane.

Effects of Metal Micro and Nano-Particles on hASCs: An In Vitro Model

As the knowledge about the interferences of nanomaterials on human staminal cells are scarce and contradictory, we undertook a comparative multidisciplinary study based on the size effect of zero-valent iron, cobalt, and nickel microparticles (MPs) and nanoparticles (NPs) using human adipose stem cells (hASCs) as a model, and evaluating cytotoxicity, morphology, cellular uptake, and gene expression. Our results suggested that the medium did not influence the cell sensitivity but, surprisingly, the iron microparticles (FeMPs) resulted in being toxic. These data were supported by modifications in mRNA expression of some genes implicated in the inflammatory response. Microscopic analysis confirmed that NPs, mainly internalized by endocytosis, persist in the vesicles without any apparent cell damage. Conversely, MPs are not internalized, and the effects on hASCs have to be ascribed to the release of ions in the culture medium, or to the reduced oxygen and nutrient exchange efficiency due to the presence of MP agglomerating around the cells. Notwithstanding the results depicting a heterogeneous scene that does not allow drawing a general conclusion, this work reiterates the importance of comparative investigations on MPs, NPs, and corresponding ions, and the need to continue the thorough verification of NP and MP innocuousness to ensure unaffected stem cell physiology and differentiation.

Isotope Tracers To Study the Environmental Fate and Bioaccumulation of Metal-Containing Engineered Nanoparticles: Techniques and Applications

The rapidly growing applicability of metal-containing engineered nanoparticles (MENPs) has made their environmental fate, biouptake, and transformation important research topics. However, considering the relatively low concentration of MENPs and the high concentration of background metals in the environment and in organisms, tracking the fate of MENPs in environment-related scenarios remains a challenge. Intrinsic labeling of MENPs with radioactive or stable isotopes is a useful tool for the highly sensitive and selective detection of MENPs in the environment and organisms, thus enabling tracing of their transformation, uptake, distribution, and clearance. In this review, we focus on radioactive/stable isotope labeling of MENPs for their environmental and biological tracing. We summarize the advantages of intrinsic radioactive/stable isotopes for MENP labeling and discuss the considerations in labeling isotope selection and preparation of labeled MENPs, as well as exposure routes and detection of labeled MENPs. In addition, current practice in the use of radioactive/stable isotope labeling of MENPs to study their environmental fate and bioaccumulation is reviewed. Future perspectives and potential applications are also discussed, including imaging techniques for radioactive- and stable-isotope-labeled MENPs, hyphenated multistable isotope tracers with speciation analysis, and isotope fractionation as a MENP tracer. It is expected that this critical review could provide the necessary background information to further advance the applications of isotope tracers to study the environmental fate and bioaccumulation of MENPs.

Toxicity, accumulation, and trophic transfer of chemically and biologically synthesized nano zero valent iron in a two species freshwater food chain

The impact of bio-remediation agent nZVI on environment is still inadequately understood, especially on aquatic food web. The study presented here has therefore considered both chemical (CS) and biological (BS) synthetic origins of nZVI and their effects on both algae and daphnia. The study is unique in its attempt to explore the possibility of trophic transfer from algae to its immediate higher niche (daphnia as the model). An equal weightage of the effects of both CS and BS nZVI on algae and daphnia has been explored here; hence it allows us to compare the capping of nZVI on toxicity. To examine the causes of observed lethality- ROS generation, effects on the activity of oxidative enzymes, membrane damage and biouptake of nZVI was analysed. The overall outcome of CS and BS nZVI on lethality was significantly different in algae and daphnia, where daphnia demonstrated relatively higher sensitivity against CS nZVI. Algae demonstrated considerable differences in CS and BS nZVI toxicity only at higher concentration. This study did not show a probable biomagnification and trophic transfer from algae to daphnia under the experimental conditions even at the highest exposure concentration. The study instigates the importance of trophic transfer to understand the possible biomagnification of nZVI among organisms of different trophic levels and eventually the consequences on environment.

l-aspartate oxidase magnetic nanoparticles: synthesis, characterization and l-aspartate bioconversion

l-aspartate oxidase (LASPO) catalyses the stereospecific oxidative deamination of l-aspartate. Here, we describe the efficient immobilization of this enzyme on Fe₃O₄ NPs resulting in a stable NP-LASPO dispersion with a good reusability.

Evaluation of tissue morphology and gene expression as biomarkers of pollution in mussel Mytilus galloprovincialis caging experiment

The ecosystem is being anthropogenically disturbed, which has serious consequences for the environment and human health, having strong social and economic impacts on the community. One of the most common methods to evaluate the effects of toxic contaminants is based on biomonitoring, e.g., placing Mytilus galloprovincialis in the polluted areas investigated. In this study, we have combined two different methods, transcriptomic and morphological analysis, with the purpose of determining whether cell morphology and the ultrastructural organization of our animal model are related to gene expression in outdoor experiments. The most pronounced changes were observed in mussel gills and digestive gland for mRNA involved in protein machinery (18S, 28S and EF1), while HSP70, MT10, CYP4Y1, SOD1, and CAT mRNAs showed scattered modifications not related to the studied area. In agreement with 18S, 28S, and EF1 mRNA evaluation, optical and electron microscopy demonstrated an initial inflammatory response of the cells that can lead to apoptosis in the caged mussels in all the polluted areas. In conclusion, the application of a multi-disciplinary approach proved to be effective for assessing the biological effects of contaminations on the health of aquatic organisms, and thus suitable to be applied in eco-toxicological studies. Although affected by several uncontrolled environmental variables, the assessment of mRNA can represent a useful endpoint for an integrated estimation of the overall threats to the sea environment within a field research approach.

Cobalt oxide nanoparticles can enter inside the cells by crossing plasma membranes

The ability of nanoparticles (NPs) to be promptly uptaken by the cells makes them both dangerous and useful to human health. It was recently postulated that some NPs might cross the plasma membrane also by a non-endocytotic pathway gaining access to the cytoplasm. To this aim, after having filled mature Xenopus oocytes with Calcein, whose fluorescence is strongly quenched by divalent metal ions, we have exposed them to different cobalt NPs quantifying quenching as evidence of the increase of the concentration of Co(2+) released by the NPs that entered into the cytoplasm. We demonstrated that cobalt oxide NPs, but not cobalt nor cobalt oxide NPs that were surrounded by a protein corona, can indeed cross plasma membranes.

Zerovalent Fe, Co and Ni nanoparticle toxicity evaluated on SKOV-3 and U87 cell lines

We have considered nanoparticles (NPs) of Fe, Co and Ni, three transition metals sharing similar chemical properties. NP dissolution, conducted by radioactive tracer method and inductively coupled plasma mass spectrometry, indicated that NiNPs and FeNPs released in the medium a much smaller amount of ions than that released by Co NPs. The two considered methodological approaches, however, gave comparable but not identical results. All NPs are readily internalized by the cells, but their quantity inside the cells is less than 5%. Cytotoxicity and gene expression experiments were performed on SKOV‐3 and U87 cells. In both cell lines, CoNPs and NiNPs were definitely more toxic than FeNPs. Real‐time polymerase chain reaction experiments aimed to evaluate modifications of the expression of genes involved in the cellular stress response (HSP70, MT2A), or susceptible to metal exposure (SDHB1 and MLL), or involved in specific cellular processes (caspase3, IQSEC1 and VMP1), gave different response patterns in the two cell lines. HSP70, for example, was highly upregulated by CoNPs and NiNPs, but only in SKOV‐3 cell lines. Overall, this work underlines the difficulties in predicting NP toxicological properties based only on their chemical characteristics. We, consequently, think that, at this stage of our knowledge, biological effects induced by metal‐based NPs should be examined on a case‐by‐case basis following studies on different in vitro models. Moreover, with the only exception of U87 exposed to Ni, our results suggest that metallic NPs have caused, on gene expression, similar effects to those caused by their corresponding ions. Copyright © 2015 The Authors. Journal of Applied Toxicology published by John Wiley & Sons, Ltd.

We have considered Fe, Co and Ni nanoparticles and studied their dissolution by radioactive tracer method and ICP‐MS. We have also performed cytotoxicity and gene expression experiments on two different cell lines. The obtained results convinced us that, at this stage of our knowledge, metal‐based nanoparticles should be examined on a case‐by‐case basis on different in vitro models. Moreover, our results suggest that metal‐based nanoparticles have caused similar effects to those caused by their corresponding ions.