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1.
Sensors (Basel) ; 21(5)2021 Mar 02.
Artigo em Inglês | MEDLINE | ID: mdl-33801222

RESUMO

This article introduces a bioinspired, cicada wing-like surface-enhanced Raman scattering (SERS) substrate based on template-stripped crossed surface relief grating (TS-CSRG). The substrate is polarization-independent, has tunable nanofeatures and can be fabricated in a cleanroom-free environment via holographic exposure followed by template-stripping using a UV-curable resin. The bioinspired nanostructures in the substrate are strategically designed to minimize the reflection of light for wavelengths shorter than their periodicity, promoting enhanced plasmonic regions for the Raman excitation wavelength at 632.8 nm over a large area. The grating pitch that enables an effective SERS signal is studied using Rhodamine 6G, with enhancement factors of the order of 1 × 104. Water contact angle measurements reveal that the TS-CSRGs are equally hydrophobic to cicada wings, providing them with potential self-cleaning and bactericidal properties. Finite-difference time-domain simulations are used to validate the nanofabrication parameters and to further confirm the polarization-independent electromagnetic field enhancement of the nanostructures. As a real-world application, label-free detection of melamine up to 1 ppm, the maximum concentration of the contaminant in food permitted by the World Health Organization, is demonstrated. The new bioinspired functional TS-CSRG SERS substrate holds great potential as a large-area, label-free SERS-active substrate for medical and biochemical sensing applications.


Assuntos
Hemípteros , Nanoestruturas , Animais , Interações Hidrofóbicas e Hidrofílicas , Nanoestruturas/toxicidade , Análise Espectral Raman , Propriedades de Superfície
2.
Artigo em Chinês | MEDLINE | ID: mdl-33781047

RESUMO

Graphene oxide is a novel two-dimensional carbon nanomaterial, but it has potential risks for the health of occupationally exposed workers. This article briefly reviews the research progress on the cytotoxic mechanism of graphene oxide and its derivatives in terms of oxidative stress, physical damage and dysfunction of enzyme activity. This review also discusses effective measures for the mitigation of cytotoxicity in order to provide helpful evidence for occupational health risk and biological safety assessment of graphene nanomaterials in China.


Assuntos
Grafite , Nanoestruturas , China , Grafite/toxicidade , Humanos , Nanoestruturas/toxicidade , Estresse Oxidativo
3.
Carbohydr Polym ; 259: 117762, 2021 May 01.
Artigo em Inglês | MEDLINE | ID: mdl-33674015

RESUMO

Biopolymer-based nanomaterials have been developed as antimicrobial and anticancer agents due to their advanced physical, chemical and biomedical characteristics. Herein, chitosan-copper oxide nanomaterial was, successfully synthesized by a green method. In this process, copper salt was nucleated with Psidium guajava leaves extract in order to form the nanomaterial in the chitosan network. Attenuated total reflection-fourier transform, infrared spectroscopy, X-ray diffraction, Dynamic light scattering, Transmission electron microscope, Field emission scanning electron microscopy/Energy dispersive X-ray analysis, X-ray photoelectron spectroscopy and Photoluminescence spectroscopy techniques were, employed to characterize the synthesized nanomaterial. The average size of the nanomaterial was identified to be ∼52.49 nm with XRD. The antibacterial study of CCuO NM showed higher activity than the commercial amoxicillin against gram-positive (G + ve) (Staphylococcus aureus, Bacillus subtilis) and gram-negative (G-ve) bacteria (Klebsiella pneumonia, Escherichia coli). CCuO NM showed in-vitro anticancer potential against human cervical cancer cells (Hela) with an IC50 concentration of 34.69 µg/mL. Photoluminescence spectrum of CCuO NM showed a green emission (oxygen vacancies) observed at ∼516 nm, which is attributed to the generation of reactive oxygen species (ROS) by the nanomaterial, which is believed, to be responsible for the biocidal (cell death) effects. These results suggested that CCuO is a promising nanomaterial that could be suitable for advanced applications in the healthcare industries.


Assuntos
Antibacterianos/química , Antineoplásicos/química , Quitosana/química , Cobre/química , Nanoestruturas/química , Animais , Antibacterianos/farmacologia , Antineoplásicos/farmacologia , Sobrevivência Celular/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Positivas/efeitos dos fármacos , Química Verde , Células HeLa , Humanos , Camundongos , Testes de Sensibilidade Microbiana , Nanoestruturas/toxicidade , Tamanho da Partícula , Folhas de Planta/química , Folhas de Planta/metabolismo , Psidium/química , Psidium/metabolismo , Espécies Reativas de Oxigênio/metabolismo
4.
ACS Appl Mater Interfaces ; 13(11): 12912-12927, 2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33715350

RESUMO

The current pandemic caused by SARS-CoV-2 has seen a widespread use of personal protective equipment, especially face masks. This has created the need to develop better and reusable protective masks with built-in antimicrobial, self-cleaning, and aerosol filtration properties to prevent the transmission of air-borne pathogens such as the coronaviruses. Herein, molybdenum disulfide (MoS2) nanosheets are used to prepare modified polycotton fabrics having excellent antibacterial activity and photothermal properties. Upon sunlight irradiation, the nanosheet-modified fabrics rapidly increased the surface temperature to ∼77 °C, making them ideal for sunlight-mediated self-disinfection. Complete self-disinfection of the nanosheet-modified fabric was achieved within 3 min of irradiation, making the fabrics favorably reusable upon self-disinfection. The nanosheet-modified fabrics maintained the antibacterial efficiency even after 60 washing cycles. Furthermore, the particle filtration efficiency of three-layered surgical masks was found to be significantly improved through incorporation of the MoS2-modified fabric as an additional layer of protective clothing, without compromising the breathability of the masks. The repurposed surgical masks could filter out around 97% of 200 nm particles and 96% of 100 nm particles, thus making them potentially useful for preventing the spread of coronaviruses (120 nm) by trapping them along with antibacterial protection against other airborne pathogens.


Assuntos
Anti-Infecciosos/química , Dissulfetos/química , Molibdênio/química , Nanoestruturas/química , Equipamento de Proteção Individual , Reciclagem , Anti-Infecciosos/farmacologia , /virologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/metabolismo , Glutationa/química , Humanos , Nanoestruturas/toxicidade , Oxirredução , Tamanho da Partícula , Espécies Reativas de Oxigênio/metabolismo , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/metabolismo , Luz Solar , Temperatura
5.
Carbohydr Polym ; 260: 117769, 2021 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-33712127

RESUMO

Periodontal defect poses a significant challenge in orthopedics. Guided Bone Regeneration (GBR) membrane is considered as one of the most successful methods applied to reconstruct alveolar bone and then to achieve periodontal defect repair/regeneration. In this paper, a novel polyamide-6/chitosan@nano-hydroxyapatite/polyamide-6 (PA6/CS@n-HA/PA6) bilayered tissue guided membranes by combining a solvent casting and an electrospinning technique was designed. The developed PA6/CS@n-HA/PA6 composites were characterized by a series of tests. The results show that n-HA/PA6 and electrospun PA6/CS layers are tightly bound by molecular interaction and chemical bonding, which enhances the bonding strength between two distinct layers. The porosity and adsorption average pore diameter of the PA6/CS@n-HA/PA6 membranes are 36.90 % and 22.61 nm, respectively. The tensile strength and elastic modulus of PA6/CS@n-HA/PA6 composites are 1.41 ± 0.18 MPa and 7.15 ± 1.09 MPa, respectively. In vitro cell culture studies demonstrate that PA6/CS@n-HA/PA6 bilayered scaffolds have biological safety, good bioactivity, biocompatibility and osteoconductivity.


Assuntos
Regeneração Óssea , Caprolactama/análogos & derivados , Quitosana/química , Durapatita/química , Membranas Artificiais , Nanoestruturas/química , Polímeros/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia , Regeneração Óssea/efeitos dos fármacos , Caprolactama/química , Adesão Celular/efeitos dos fármacos , Diferenciação Celular/efeitos dos fármacos , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Camundongos , Nanofibras/química , Nanoestruturas/toxicidade , Porosidade , Propriedades de Superfície , Resistência à Tração
6.
Environ Sci Pollut Res Int ; 28(14): 16962-16981, 2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33638785

RESUMO

The production and demand of nanoparticles in the manufacturing sector and personal care products, release a large number of engineered nanoparticles (ENPs) into the atmosphere, aquatic ecosystems, and terrestrial environments. The intentional or involuntary incorporation of ENPs into the environment is carried out through different processes. The ENPs are combined with other compounds and release into the atmosphere, settling on the ground due to the water cycle or other atmospheric phenomena. In the case of aquatic ecosystems, the ENPs undergo hetero-aggregation and sedimentation, reaching different living organisms and flora, as well as groundwater. Accordingly, the high mobility of ENPs in diverse ecosystems is strongly related to physical, chemical, and biological processes. Recent studies have been focused on the toxicological effects of a wide variety of ENPs using different validated biological models. This literature review emphasizes the study of toxicological effects related to using the most common ENPs, specifically metal and metal/oxides-based nanoparticles, addressing different synthesis methodologies, applications, and toxicological evaluations. The results suggest negative impacts on biological models, such as oxidative stress, metabolic and locomotive toxicity, DNA replication dysfunction, and bioaccumulation. Finally, it was consulted the protocols for the control of risks, following the assessment and management process, as well as the classification system for technological alternatives and risk management measures of ENPs, which are useful for the transfer of technology and nanoparticles commercialization.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Nanoestruturas , Ecossistema , Nanopartículas Metálicas/toxicidade , Metais , Nanoestruturas/toxicidade , Óxidos
7.
Adv Mater ; 33(10): e2007847, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33538037

RESUMO

The graphene revolution, which has taken place during the last 15 years, has represented a paradigm shift for science. The extraordinary properties possessed by this unique material have paved the road to a number of applications in materials science, optoelectronics, energy, and sensing. Graphene-related materials (GRMs) are now produced in large scale and have found niche applications also in the biomedical technologies, defining new standards for drug delivery and biosensing. Such advances position GRMs as novel tools to fight against the current COVID-19 and future pandemics. In this regard, GRMs can play a major role in sensing, as an active component in antiviral surfaces or in virucidal formulations. Herein, the most promising strategies reported in the literature on the use of GRM-based materials against the COVID-19 pandemic and other types of viruses are showcased, with a strong focus on the impact of functionalization, deposition techniques, and integration into devices and surface coatings.


Assuntos
/diagnóstico , Grafite/química , Nanoestruturas/química , Anticorpos Imobilizados/química , Anticorpos Imobilizados/imunologia , Antivirais/química , Antivirais/farmacologia , Técnicas Biossensoriais/métodos , /virologia , Técnicas Eletroquímicas , Eletrodos , Humanos , Limite de Detecção , Nanoestruturas/toxicidade , /isolamento & purificação , Propriedades de Superfície , Proteínas Virais/análise , Proteínas Virais/imunologia
8.
Ecotoxicol Environ Saf ; 212: 112018, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33550076

RESUMO

The underlying mechanisms of microRNAs (miRNAs) in regulating nanoplastic toxicity are still largely unclear in organisms. In nanopolystyrene (NPS) exposed Caenorhabditis elegans, the expression of mir-76 (a neuronal miRNA) was significantly decreased, and the mir-76 mutant was resistant to the toxicity of NPS. The aim of this study was to determine the molecular basis of mir-76 in controlling NPS toxicity in nematodes. The mir-76 mutation increased expression of glb-10 encoding a globin protein in NPS (1 µg/L) exposed nematodes. Exposure to NPS (1-100 µg/L) increased the glb-10 expression, and the glb-10(RNAi) worm was susceptible to NPS toxicity in inducing reactive oxygen species (ROS) production and in decreasing locomotion behavior. Using ROS production and locomotion behavior as endpoints, mutation of glb-10 inhibited resistance of mir-76 mutant to NPS toxicity, and neuronal overexpression of mir-76 inhibited the resistance to NPS toxicity in nematodes overexpressing neuronal glb-10 containing 3' untranslated region (3'UTR). Thus, GLB-10 functioned as a target of mir-76 in the neurons to regulate the NPS toxicity. Moreover, a signaling cascade of HRG-7-HRG-5 required for the control of heme homeostasis was identified to function downstream of neuronal GLB-10 to regulate the NPS toxicity. In this signaling cascade, the neuronal HRG-7 regulated the NPS toxicity by antagonizing function of intestinal HRG-5. Furthermore, in the intestine, HRG-5 controlled NPS toxicity by inhibiting functions of hypoxia-inducible transcriptional factor HIF-1 and transcriptional factor ELT-2. Our results highlight the crucial function of heme homeostasis related signaling in regulating the NPS toxicity in organisms.


Assuntos
Proteínas de Caenorhabditis elegans/genética , Caenorhabditis elegans/efeitos dos fármacos , Heme/metabolismo , Homeostase , MicroRNAs/genética , Nanoestruturas/toxicidade , Poliestirenos/toxicidade , Animais , Caenorhabditis elegans/genética , Caenorhabditis elegans/metabolismo , Intestinos/efeitos dos fármacos , Nanoestruturas/química , Neurônios/efeitos dos fármacos , Neurônios/metabolismo , Poliestirenos/química , Interferência de RNA , Espécies Reativas de Oxigênio/metabolismo , Transdução de Sinais
9.
Sci Data ; 8(1): 49, 2021 02 08.
Artigo em Inglês | MEDLINE | ID: mdl-33558569

RESUMO

Toxicogenomics (TGx) approaches are increasingly applied to gain insight into the possible toxicity mechanisms of engineered nanomaterials (ENMs). Omics data can be valuable to elucidate the mechanism of action of chemicals and to develop predictive models in toxicology. While vast amounts of transcriptomics data from ENM exposures have already been accumulated, a unified, easily accessible and reusable collection of transcriptomics data for ENMs is currently lacking. In an attempt to improve the FAIRness of already existing transcriptomics data for ENMs, we curated a collection of homogenized transcriptomics data from human, mouse and rat ENM exposures in vitro and in vivo including the physicochemical characteristics of the ENMs used in each study.


Assuntos
Nanoestruturas/toxicidade , Toxicogenética , Transcriptoma , Animais , Coleta de Dados , Curadoria de Dados , Humanos , Camundongos , Ratos
10.
Environ Sci Technol ; 55(2): 1122-1133, 2021 01 19.
Artigo em Inglês | MEDLINE | ID: mdl-33393283

RESUMO

Engineered nanomaterials (ENMs), especially transition metal dichalcogenide (TMDC), have received great attention in recent years due to their advantageous properties and applications in various fields and are inevitably released into the environment during their life cycle. However, the effect of natural nanocolloids, widely distributed in the aquatic environment, on the environmental transformation and ecotoxicity of ENMs remains largely unknown. In this study, the effects of natural nanocolloids were compared to humic acid on the environmental transformation and ecotoxicity of single-layer molybdenum disulfide (SLMoS2), a representative TMDC. SLMoS2 with nanocolloids or humic acid (HA) enhanced their dispersion and Mo ion release in deionized water. Nanocolloids induced growth inhibition, reactive oxygen species (ROS) elevation, and cell permeability. Low-toxicity SLMoS2 combined with nanocolloids will enhance the above adverse effects. SLMoS2-nanocolloids induced serious damage (cell distortion and deformation), SLMoS2 internalization, and metabolic perturbation on Chlorella vulgaris (C. vulgaris). In contrast, the addition of HA induced the growth promotion and lower ROS level, inhibited the internalization of SLMoS2, and mitigated metabolic perturbation on C. vulgaris. This work provides insights into the effect of natural nanocolloids on the behaviors and biological risks of ENMs in aquatic environments, deserving substantial future attention.


Assuntos
Chlorella vulgaris , Nanoestruturas , Dissulfetos , Substâncias Húmicas , Molibdênio/toxicidade , Nanoestruturas/toxicidade
11.
Chemosphere ; 272: 129603, 2021 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-33485043

RESUMO

The utilization of tungsten disulfide (WS2) nanomaterials in distinct applications is raising due to their unique physico-chemical properties, such as low friction coefficient and high strength, which highlights the necessity to study their potential toxicological effects, due to the potential increase of environmental and human exposure. The aim of this work was to analyze commercially available aqueous dispersions of monolayer tungsten disulfide (2D WS2) nanomaterials with distinct lateral size employing a portfolio of physico-chemical and toxicological evaluations. The structure and stoichiometry of monolayer tungsten disulfide (WS2-ACS-M) and nano size monolayer tungsten disulfide (WS2-ACS-N) was analyzed by Raman spectroscopy, whereas a more quantitative approach to study the nature of formed oxidized species was undertaken employing X-ray photoelectron spectroscopy. Adenocarcinomic human alveolar basal epithelial cells (A549 cells) and the ecotoxicology model Saccharomyces cerevisiae were selected as unicellular eukaryotic systems to assess the cytotoxicity of the nanomaterials. Cell viability and reactive oxygen species (ROS) determinations demonstrated different toxicity levels depending on the cellular model used. While both 2D WS2 suspensions showed very low toxicity towards the A549 cells, a comparable concentration (160 mg L-1) reduced the viability of yeast cells. The toxicity of a nano size 2D WS2 commercialized in dry form from the same provider was also assessed, showing ability to reduce yeast cells viability as well. Overall, the presented data reveal the physico-chemical properties and the potential toxicity of commercial 2D WS2 aqueous suspensions when interacting with distinct eukaryotic organisms, showing differences in function of the biological system exposed.


Assuntos
Nanoestruturas , Tungstênio , Células A549 , Dissulfetos/toxicidade , Humanos , Nanoestruturas/toxicidade , Saccharomyces cerevisiae , Suspensões , Tungstênio/toxicidade
12.
Nanotoxicology ; 15(2): 257-275, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33503388

RESUMO

Safety on the use of magnetic nanomaterials (MNMs) has become an active topic of research given all the recent applications of these materials in various fields. It is known that the toxicity of MNMs depends on size, shape, and surface functionalization. In this study, we evaluate the biocompatibility with different aquatic organisms of engineered MNMs-CIT with excellent aqueous dispersion and long-term colloidal stability. Primary producers (the alga Pseudokirchneriella subcapitata), primary consumers (the rotifer Lecane papuana), and predators (the fish, Danio rerio) interacted with these materials in acute and sub-chronic toxicity tests. Our results indicate that P. subcaptita was the most sensitive taxon to MNMs-CIT. Inhibition of their population growth (IC50 = 22.84 mg L-1) elicited cell malformations and increased the content of photosynthetic pigments, likely due to inhibition of cell division (as demonstrated in AFM analysis). For L. papuana, the acute exposure to MNMs shows no significant mortality. However, adverse effects such as decreased rate of population and altered swimming patterns arise after chronic interaction with MNMs. For D. rerio organisms on early life stages, their exposure to MNMs results in delayed hatching of eggs, diminished survival of larvae, altered energy resources allocation (measured as the content of total carbohydrates, lipids, and protein), and increased glucose demand. As to our knowledge, this is the first study that includes three different trophic levels to assess the effect of MNMs in aquatic organisms; furthermore, we demonstrated that these MNMs pose hazards on aquatic food webs at low concentrations (few mgL-1).


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Cloretos/toxicidade , Compostos Férricos/toxicidade , Compostos Ferrosos/toxicidade , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade , Animais , Biomarcadores/análise , Cloretos/química , Compostos Férricos/química , Compostos Ferrosos/química , Cadeia Alimentar , Larva/efeitos dos fármacos , Fenômenos Magnéticos , Microalgas/efeitos dos fármacos , Nanoestruturas/química , Tamanho da Partícula , Rotíferos/efeitos dos fármacos , Propriedades de Superfície , Poluentes Químicos da Água/química , Peixe-Zebra/crescimento & desenvolvimento
13.
Mar Pollut Bull ; 164: 111970, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33517086

RESUMO

This study aimed to investigate the toxicity of innovative antifouling nanostructured biocides DCOIT and silver associated to silica nanocapsules (SiNC) on the tropical microcrustacean Mysidopsis juniae. The toxicity of the tested compounds can be summarized as follows (acute tests): DCOIT > SiNC-Ag > SiNC-DCOIT > SiNC-DCOIT-Ag > SiNC > Ag; (chronic tests): SiNC-Ag > SiNC-DCOIT-Ag > DCOIT > Ag > SiNC, although it was not possible to determine the chronic toxicity of SiNC-DCOIT. In general, our data demonstrated that mysids were more sensitive than most temperate species, and it was possible to conclude that the combination SiNC-DCOIT-Ag showed less acute toxicity in comparison to the isolated active compounds, reinforcing data obtained for species from temperate environments on the potential use of nanomaterial to reduce toxicity to non-target species. However, despite representing less risk to the environment, the compound SiNC-DCOIT-Ag is still very toxic to the non-target tropical mysid.


Assuntos
Desinfetantes , Nanoestruturas , Poluentes Químicos da Água , Animais , Crustáceos , Desinfetantes/toxicidade , Nanoestruturas/toxicidade , Poluentes Químicos da Água/toxicidade
14.
Int J Nanomedicine ; 16: 161-184, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33447033

RESUMO

The emergence of nanotechnology as a key enabling technology over the past years has opened avenues for new and innovative applications in nanomedicine. From the business aspect, the nanomedicine market was estimated to worth USD 293.1 billion by 2022 with a perception of market growth to USD 350.8 billion in 2025. Despite these opportunities, the underlying challenges for the future of engineered nanomaterials (ENMs) in nanomedicine research became a significant obstacle in bringing ENMs into clinical stages. These challenges include the capability to design bias-free methods in evaluating ENMs' toxicity due to the lack of suitable detection and inconsistent characterization techniques. Therefore, in this literature review, the state-of-the-art of engineered nanomaterials in nanomedicine, their toxicology issues, the working framework in developing a toxicology benchmark and technical characterization techniques in determining the toxicity of ENMs from the reported literature are explored.


Assuntos
Nanomedicina , Nanoestruturas/química , Nanotecnologia/métodos , Aprovação de Drogas , Saúde , Humanos , Nanoestruturas/toxicidade , Estados Unidos , United States Food and Drug Administration
15.
Ecotoxicol Environ Saf ; 208: 111697, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396028

RESUMO

Owing to the unique properties and useful applications in numerous fields, nanomaterials (NMs) received a great attention. The mass production of NMs has raised major concern for the environment. Recently, some altered growth patterns in plants have been reported due to the plant-NMs interactions. However, for NMs safe applications in agriculture and medicine, a comprehensive understanding of bio-nano interactions is crucial. The main goal of this review article is to summarize the results of the toxicological studies that have shown the in vitro and in vivo interactions of NMs with plants. The toxicity mechanisms are briefly discussed in plants as the defense mechanism works to overcome the stress caused by NMs implications. Indeed, the impact of NMs on plants varies significantly with many factors including physicochemical properties of NMs, culture media, and plant species. To investigate the impacts, dose metrics is an important analysis for assaying toxicity and is discussed in the present article to broadly open up different aspects of nanotoxicological investigations. To access reliable quantification and measurement in laboratories, standardized methodologies are crucial for precise dose delivery of NMs to plants during exposure. Altogether, the information is significant to researchers to describe restrictions and future perspectives.


Assuntos
Ecotoxicologia/normas , Poluentes Ambientais/toxicidade , Nanoestruturas/toxicidade , Plantas/efeitos dos fármacos , Agricultura , Ecotoxicologia/tendências , Poluentes Ambientais/química , Humanos , Nanoestruturas/química , Desenvolvimento Vegetal/efeitos dos fármacos , Plantas/classificação , Plantas/metabolismo , Especificidade da Espécie , Estresse Fisiológico/efeitos dos fármacos
16.
Ecotoxicol Environ Saf ; 208: 111634, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33396154

RESUMO

The Quantitative Structure-Activity Relationship (QSAR) has been used to investigate organic mixtures but QSAR in the nanomaterial field (QNAR) is still new. Toxicity is a result of the interaction of many substances. QNAR research focuses on a single nanomaterial in the long-term. It is difficult to find an appropriate descriptor to build a model due to the complexity of the mixture. Here, we attempt to build a QNAR model to predict cell viability for HK-2 cells exposed to a mixture containing nano-TiO2 and heavy metals. HK-2 cells were exposed to four groups of mixtures containing heavy-metals and nanomaterials and CCK8 was added to obtain the number of living cells. At the same time, ROS was investigated to study this mechanism. Each descriptor of the components and mixtures were obtained using the formula Dmix= [Formula: see text] respectively. We used the Multiple Partial Least Squares Regression (PLS) and Random Forest Regression (RF) to build a QNAR model. Both models reliably predict and assess viability of HK-2 cells exposed to the mixture. The RF model showed greater stability and higher precision in toxicity predictability and can be applied to environmental nano-toxicology.


Assuntos
Ecotoxicologia/métodos , Metais Pesados/toxicidade , Nanoestruturas/toxicidade , Relação Quantitativa Estrutura-Atividade , Titânio/toxicidade , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Humanos , Metais Pesados/química , Nanoestruturas/química , Espécies Reativas de Oxigênio/metabolismo , Titânio/química
17.
Ecotoxicol Environ Saf ; 212: 111979, 2021 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-33513482

RESUMO

Silicon oxide (SiO2) nanostructures (SiO2NS) are increasingly being incorporated into an array of products, notably in the food, pharmaceutical, medical industries and in water treatment systems. Amorphous SiO2NS have low toxicity, however, due to their great versatility, superficial modifications can be made and these altered structures require toxicological investigation. In this study, SiO2NS were synthetized and amine-functionalized with the molecules (3-aminopropyl)triethoxysilane (APTMS) and 3-[2-(2-aminoethylamino)ethylamino]propyltrimethoxysilane (AEAEAPTMS), named SiO2NS@1 and SiO2NS@3, respectively. The bare SiO2NS, SiO2NS@1 and SiO2NS@3 samples were characterized and the influence of the culture medium used in the toxicological assays was also evaluated. The effect of amine functionalization of SiO2NS was investigated through acute and chronic toxicity assays with Daphnia magna. Modifications to ultrastructures of the intestine and eggs of these organisms were observed in TEM and SEM analysis. The toxicity was influenced by the surface modifications and a possible Trojan horse effect was highlighted, particularly in the case of chronic exposure. Exposure to all NSs promoted alterations in the microvilli and mitochondria of the D. magna intestine and some damage to egg cells was also observed. The results demonstrate the importance of carrying out a full characterization of these materials, since surface modifications can enhance their toxic potential.


Assuntos
Daphnia/fisiologia , Nanoestruturas/toxicidade , Dióxido de Silício/toxicidade , Aminas , Animais , Bioensaio , Daphnia/efeitos dos fármacos , Testes de Toxicidade Aguda , Testes de Toxicidade Crônica , Poluentes Químicos da Água/toxicidade
18.
Chemosphere ; 262: 128058, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33182140

RESUMO

Owing to the superlative properties, engineered nanomaterials (ENM) are being used in food, cosmetics, medicine, and electronics. Therefore, exogenous ENM can be housed into humans through a multitude of exposure routes, leading to compromise of the biomolecules' functionalities through structural deformations, and even at the metabolic level. Consequently, it is of great importance to understand the perturbations introduced at the metabolic level for the timely risk assessment (RA) of ENM. Current technological advancements in metabolomics empower us to visualize the metabolic dysregulations in biological cells, tissues, and living objects, instigated by the ENM. Given the fact, we propose multitiered untargeted metabolomics for the risk assessment of ENM. We propose largely validated experimental design principles that enable the well-organized and authentic identification of metabolic dysregulation connected with a newly engineered nanomaterial. Our scheme could participate in the enhanced transparency of the RA course of rapidly emerging ENM.


Assuntos
Redes e Vias Metabólicas/efeitos dos fármacos , Metabolômica/métodos , Nanoestruturas , Humanos , Nanoestruturas/química , Nanoestruturas/toxicidade , Nanotecnologia , Medição de Risco , Transdução de Sinais
19.
Environ Res ; 194: 110669, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33359698

RESUMO

Recent studies have shown that nanosized materials including plastics as a major cause of concern in the aquatic ecosystem. Fortunately, in the aquatic environment, the surface of the materials is often colonized by exudates of aquatic microorganisms (biofilm), where these materials are attached and surrounded by a secreted matrix with a sticky layer. The significance of these biofilms on the existence and beneficial implications of these pollutants has been studied in recent decades. Here we develop the concept of these pollutants as a complex matrix of polymers to which Extracellular Polymeric Substances (EPS) binds to form eco-corona modifying its density and surface charge of these particles. This review critically integrates the outstanding properties and functions of algal EPS in the aquatic environment and their dynamic interactions of early colonization on the surface of these pollutants, the impact of biofilm formation on stability, reactivity and, toxicity from the current literature. Due to the modifications of the environmental processes, EPS can have an impact on the toxicity thus special attention is focused on their behavior to decrease the toxicity of the pollutants in the aquatic environment. Although there has been an increasing number of researches in this area, further progress is needed to explore the extent to which ecological processes could be impacted, including the modifications in the behavior of aquatic pollutants. Thus, this review provides a recent perspective into the mechanisms of how eco-corona formation mitigates the toxicity of nanomaterials prevalent in aquatic ecosystems.


Assuntos
Ecossistema , Nanoestruturas , Biofilmes , Matriz Extracelular de Substâncias Poliméricas , Nanoestruturas/toxicidade , Plásticos
20.
Nanotoxicology ; 15(2): 145-166, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33320695

RESUMO

New registration requirements for nanomaterials under REACH consider the possibility to form 'sets of similar nanoforms' for a joined human health and environmental hazard, exposure and risk assessment. We developed a tool to create and justify sets of similar nanoforms and to ensure that each of the nanoforms is sufficiently similar to all other nanoforms. The decision logic is following the ECHA guidance in a transparent and evidence-based manner. For each two nanoforms the properties under consideration are compared and corresponding thresholds for maximal differences are proposed. In tier1, similarity is assessed based on intrinsic properties that mostly correspond to those required for nanoform identification under REACH: composition, impurities/additives, size, crystallinity, shape and surface treatment. Moreover, potential differences in the agglomeration/aggregation state resulting from different production processes are considered. If nanoforms were not sufficiently similar based on tier1 criteria, additional data from functional assays are required in tier2. In rare cases, additional short-term in vivo rodent data could be required in a third tier. Data required by tier 2 are triggered by the intrinsic properties in the first tier that did not match the similarity criteria. Most often this will be data on dissolution and surface reactivity followed by in vitro toxicity, dispersion stability, dustiness. Out of several nanoforms given by the user, the tool concludes which nanoforms could be justified to be in the same set and which nanoforms are outside. It defines the boundaries of sets of similar nanoforms and generates a justification for the REACH registration.


Assuntos
Ecotoxicologia/métodos , Exposição Ambiental/efeitos adversos , Nanoestruturas , Qualidade de Produtos para o Consumidor , Tomada de Decisões , Ecotoxicologia/legislação & jurisprudência , Exposição Ambiental/análise , União Europeia , Regulamentação Governamental , Humanos , Nanoestruturas/química , Nanoestruturas/classificação , Nanoestruturas/toxicidade , Tamanho da Partícula , Medição de Risco/métodos , Solubilidade , Propriedades de Superfície , Testes de Toxicidade
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