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1.
Proc Natl Acad Sci U S A ; 119(26): e2117083119, 2022 06 28.
Artigo em Inglês | MEDLINE | ID: mdl-35737841

RESUMO

There are still significant knowledge gaps in understanding the intrusion and retention of exogeneous particles into the central nervous system (CNS). Here, we uncovered various exogeneous fine particles in human cerebrospinal fluids (CSFs) and identified the ambient environmental or occupational exposure sources of these particles, including commonly found particles (e.g., Fe- and Ca-containing ones) and other compositions that have not been reported previously (such as malayaite and anatase TiO2), by mapping their chemical and structural fingerprints. Furthermore, using mouse and in vitro models, we unveiled a possible translocation pathway of various inhaled fine particles from the lung to the brain through blood circulation (via dedicated biodistribution and mechanistic studies). Importantly, with the aid of isotope labeling, we obtained the retention kinetics of inhaled fine particles in mice, indicating a much slower clearance rate of localized exogenous particles from the brain than from other main metabolic organs. Collectively, our results provide a piece of evidence on the intrusion of exogeneous particles into the CNS and support the association between the inhalation of exogenous particles and their transport into the brain tissues. This work thus provides additional insights for the continued investigation of the adverse effects of air pollution on the brain.


Assuntos
Encéfalo , Pulmão , Material Particulado , Animais , Sangue , Encéfalo/metabolismo , Humanos , Pulmão/química , Pulmão/metabolismo , Camundongos , Tamanho da Partícula , Material Particulado/análise , Material Particulado/sangue , Material Particulado/química , Material Particulado/metabolismo , Distribuição Tecidual
2.
Proc Natl Acad Sci U S A ; 119(23): e2200363119, 2022 06 07.
Artigo em Inglês | MEDLINE | ID: mdl-35653569

RESUMO

The nanomaterial­protein "corona" is a dynamic entity providing a synthetic­natural interface mediating cellular uptake and subcellular distribution of nanomaterials in biological systems. As nanomaterials are central to the safe-by-design of future nanomedicines and the practice of nanosafety, understanding and delineating the biological and toxicological signatures of the ubiquitous nanomaterial­protein corona are precursors to the continued development of nano­bio science and engineering. However, despite well over a decade of extensive research, the dynamics of intracellular release or exchange of the blood protein corona from nanomaterials following their cellular internalization remains unclear, and the biological footprints of the nanoparticle­protein corona traversing cellular compartments are even less well understood. To address this crucial bottleneck, the current work screened evolution of the intracellular protein corona along the endocytotic pathway from blood via lysosomes to cytoplasm in cancer cells. Intercellular proteins, including pyruvate kinase M2 (PKM2), and chaperones, displaced some of the initially adsorbed blood proteins from the nanoparticle surface, which perturbed proteostasis and subsequently incited chaperone-mediated autophagy (CMA) to disrupt the key cellular metabolism pathway, including glycolysis and lipid metabolism. Since proteostasis is key to the sustainability of cell function, its collapse and the resulting CMA overdrive spell subsequent cell death and aging. Our findings shed light on the consequences of the transport of extracellular proteins by nanoparticles on cell metabolism.


Assuntos
Nanoestruturas , Coroa de Proteína , Coroa de Proteína/metabolismo , Proteômica , Proteostase , Piruvato Quinase/metabolismo
3.
Environ Sci Technol ; 58(21): 9051-9060, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38742946

RESUMO

Research on plant-nanomaterial interactions has greatly advanced over the past decade. One particularly fascinating discovery encompasses the immunomodulatory effects in plants. Due to the low doses needed and the comparatively low toxicity of many nanomaterials, nanoenabled immunomodulation is environmentally and economically promising for agriculture. It may reduce environmental costs associated with excessive use of chemical pesticides and fertilizers, which can lead to soil and water pollution. Furthermore, nanoenabled strategies can enhance plant resilience against various biotic and abiotic stresses, contributing to the sustainability of agricultural ecosystems and the reduction of crop losses due to environmental factors. While nanoparticle immunomodulatory effects are relatively well-known in animals, they are still to be understood in plants. Here, we provide our perspective on the general components of the plant's immune system, including the signaling pathways, networks, and molecules of relevance for plant nanomodulation. We discuss the recent scientific progress in nanoenabled immunomodulation and nanopriming and lay out key avenues to use plant immunomodulation for agriculture. Reactive oxygen species (ROS), the mitogen-activated protein kinase (MAPK) cascade, and the calcium-dependent protein kinase (CDPK or CPK) pathway are of particular interest due to their interconnected function and significance in the response to biotic and abiotic stress. Additionally, we underscore that understanding the plant hormone salicylic acid is vital for nanoenabled applications to induce systemic acquired resistance. It is suggested that a multidisciplinary approach, incorporating environmental impact assessments and focusing on scalability, can expedite the realization of enhanced crop yields through nanotechnology while fostering a healthier environment.


Assuntos
Agricultura , Nanoestruturas , Imunidade Vegetal
4.
Environ Sci Technol ; 58(2): 1211-1222, 2024 Jan 16.
Artigo em Inglês | MEDLINE | ID: mdl-38173352

RESUMO

Molybdenum disulfide (nano-MoS2) nanomaterials have shown great potential for biomedical and catalytic applications due to their unique enzyme-mimicking properties. However, their potential agricultural applications have been largely unexplored. A key factor prior to the application of nano-MoS2 in agriculture is understanding its behavior in a complex soil-plant system, particularly in terms of its transformation. Here, we investigate the distribution and transformation of two types of nano-MoS2 (MoS2 nanoparticles and MoS2 nanosheets) in a soil-soybean system through a combination of synchrotron radiation-based X-ray absorption near-edge spectroscopy (XANES) and single-particle inductively coupled plasma mass spectrometry (SP-ICP-MS). We found that MoS2 nanoparticles (NPs) transform dynamically in soil and plant tissues, releasing molybdenum (Mo) and sulfur (S) that can be incorporated gradually into the key enzymes involved in nitrogen metabolism and the antioxidant system, while the rest remain intact and act as nanozymes. Notably, there is 247.9 mg/kg of organic Mo in the nodule, while there is only 49.9 mg/kg of MoS2 NPs. This study demonstrates that it is the transformation that leads to the multifunctionality of MoS2, which can improve the biological nitrogen fixation (BNF) and growth. Therefore, MoS2 NPs enable a 30% increase in yield compared to the traditional molybdenum fertilizer (Na2MoO4). Excessive transformation of MoS2 nanosheets (NS) leads to the overaccumulation of Mo and sulfate in the plant, which damages the nodule function and yield. The study highlights the importance of understanding the transformation of nanomaterials for agricultural applications in future studies.


Assuntos
Nanoestruturas , Solo , Solo/química , Glycine max , Molibdênio , Agricultura
5.
Environ Res ; 252(Pt 1): 118396, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38331143

RESUMO

The recombination of photogenerated carrier leads to inefficient Fe2+ regeneration, which limits the extensive application of heterogeneous photo-Fenton. Here, a novel Fe@Fe2O3/BiOBr catalyst with Z-scheme heterojunction structure is designed, and the establishment of the Z-scheme heterojunction facilitates the separation and transfer of photogenerated carrier and maintains the superior redox capability of the system. As-prepared Fe@Fe2O3/BiOBr catalyst exhibits outstanding catalytic performance and stability, especially for the optimum composite FFB-3, its degradation efficiency of tetracycline (TC) achieves 98.22% and the mineralization degree reaches 59.48% within 90 min under natural pH. The preeminent catalytic efficiency benefited from the synergistic of heterogeneous photo-Fenton and Z-scheme carriers transfer mechanism, where Fe2+ regeneration was achieved by photogenerated electrons, and increased hydroxyl radicals were produced with the participation of H2O2 in-situ generated. The results of free-radical scavenging experiment and ESR illustrated that •OH, •O2-, 1O2 and h+ were active species participating in TC degradation. Furthermore, the TC degradation paths were proposed according to LC-MS, and the toxicity evaluation result showed that the toxicity of TC solutions was markedly decreased after degradation. This study provides an innovative strategy for heterogeneous photo-Fenton degradation of antibiotic contaminations by constructing Z-scheme heterojunctions.


Assuntos
Bismuto , Peróxido de Hidrogênio , Tetraciclina , Tetraciclina/química , Tetraciclina/toxicidade , Peróxido de Hidrogênio/química , Bismuto/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/toxicidade , Ferro/química , Antibacterianos/química , Antibacterianos/toxicidade , Compostos Férricos/química , Compostos Férricos/toxicidade , Animais , Catálise
6.
Environ Res ; 258: 119360, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38852830

RESUMO

The aggregation and limited activity of nanoscale zero-valent iron (NZVI) in aqueous media hinder its practical application. In this study, a cost-effective, environmentally friendly, robust, and efficient synthesis method for NZVI-based composite was developed. NZVI@Chitin-modified ZSM-5 (NZVI@C-ZSM) composite was facilely and greenly synthesized by loading NZVI into alkali-modified ZSM-5 molecular sieves after modifying with chitin as a surfactant and binder. NZVI@C-ZSM exhibited remarkable efficacy in TC removal, achieving a removal efficiency of 97.72% within 60 min. Compared with pristine NZVI, NZVI@C-ZSM demonstrated twice the removal efficiency, indicating that NZVI@C-ZSM effectively improved the dispersion and stability of NZVI. This enhancement provided more reactive sites for generating reactive oxygen species (ROS), significantly boosting catalytic activity and durability while reducing the potential risk of secondary pollution. An improved two-parameter pseudo-first-order kinetic model was used to effectively characterize the reaction kinetics. The mechanism for TC removal primarily involved an adsorption process and chemical oxidation-reduction reactions induced by hydroxyl radicals (•OH) and superoxide radicals (•O2-). Three potential degradation pathways for TC were suggested. Furthermore, NZVI@C-ZSM exhibited good resistance to interference, suggesting its broad potential for practical applications in complex environmental conditions. This study offers a viable material and method for addressing the issue of antibiotic-contaminated water, with potential applications in water resource management.

7.
Proc Natl Acad Sci U S A ; 118(28)2021 07 13.
Artigo em Inglês | MEDLINE | ID: mdl-34260400

RESUMO

Understanding the potential of nanomaterials (NMs) to cross the blood-brain barrier (BBB), as a function of their physicochemical properties and subsequent behavior, fate, and adverse effect beyond that point, is vital for evaluating the neurological effects arising from their unintentional entry into the brain, which is yet to be fully explored. This is not only due to the complex nature of the brain but also the existing analytical limitations for characterization and quantification of NMs in the complex brain environment. By using a fit-for-purpose analytical workflow and an in vitro BBB model, we show that the physiochemical properties of metallic NMs influence their biotransformation in biological matrices, which in turn modulates the transport form, efficiency, amounts, and pathways of NMs through the BBB and, consequently, their neurotoxicity. The data presented here will support in silico modeling and prediction of the neurotoxicity of NMs and facilitate the tailored design of safe NMs.


Assuntos
Barreira Hematoencefálica/metabolismo , Metais/química , Nanoestruturas/química , Astrócitos/metabolismo , Biotransformação , Encéfalo/irrigação sanguínea , Células Endoteliais/metabolismo , Exocitose , Humanos , Microvasos/citologia , Modelos Biológicos , Permeabilidade , Transcitose
8.
Int J Mol Sci ; 25(10)2024 May 10.
Artigo em Inglês | MEDLINE | ID: mdl-38791255

RESUMO

A robust predictive model was developed using 136 novel peroxisome proliferator-activated receptor delta (PPARδ) agonists, a distinct subtype of lipid-activated transcription factors of the nuclear receptor superfamily that regulate target genes by binding to characteristic sequences of DNA bases. The model employs various structural descriptors and docking calculations and provides predictions of the biological activity of PPARδ agonists, following the criteria of the Organization for Economic Co-operation and Development (OECD) for the development and validation of quantitative structure-activity relationship (QSAR) models. Specifically focused on small molecules, the model facilitates the identification of highly potent and selective PPARδ agonists and offers a read-across concept by providing the chemical neighbours of the compound under study. The model development process was conducted on Isalos Analytics Software (v. 0.1.17) which provides an intuitive environment for machine-learning applications. The final model was released as a user-friendly web tool and can be accessed through the Enalos Cloud platform's graphical user interface (GUI).


Assuntos
PPAR delta , Relação Quantitativa Estrutura-Atividade , Software , PPAR delta/agonistas , PPAR delta/química , PPAR delta/metabolismo , Simulação de Acoplamento Molecular , Humanos , Aprendizado de Máquina
9.
Environ Sci Technol ; 57(19): 7547-7558, 2023 05 16.
Artigo em Inglês | MEDLINE | ID: mdl-37134233

RESUMO

Nickel (Ni) is a trace element beneficial for plant growth and development and could improve crop yield by stimulating urea decomposition and nitrogen-fixing enzyme activity. A full life cycle study was conducted to compare the long-term effects of soil-applied NiO nanoparticles (n-NiO), NiO bulk (b-NiO), and NiSO4 at 10-200 mg kg-1 on plant growth and nutritional content of soybean. n-NiO at 50 mg kg-1 significantly promoted the seed yield by 39%. Only 50 mg kg-1 n-NiO promoted total fatty acid content and starch content by 28 and 19%, respectively. The increased yield and nutrition could be attributed to the regulatory effects of n-NiO, including photosynthesis, mineral homeostasis, phytohormone, and nitrogen metabolism. Furthermore, n-NiO maintained a Ni2+ supply for more extended periods than NiSO4, reducing potential phytotoxicity concerns. Single-particle inductively coupled plasma mass spectrometry (sp-ICP-MS) for the first time confirmed that the majority of the Ni in seeds is in ionic form, with only 28-34% as n-NiO. These findings deepen our understanding of the potential of nanoscale and non-nanoscale Ni to accumulate and translocate in soybean, as well as the long-term fate of these materials in agricultural soils as a strategy for nanoenabled agriculture.


Assuntos
Nanopartículas , Níquel , Níquel/química , Glycine max , Nitrogênio , Solo
10.
Ecotoxicol Environ Saf ; 251: 114564, 2023 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-36682184

RESUMO

Microplastics (MPs) have been widely detected in the world's water, which may pose a significant threat to the ecosystem as a whole and have been a subject of much attention because their presence impacts seas, lakes, rivers, and even the Polar Regions. There have been numerous studies that report direct adverse effects on marine organisms, but only a few have explored their ecological effects on freshwater organisms. In this field, there is still a lack of a systematic overview of the toxic effects and mechanisms of MPs on aquatic organisms, as well as a consistent understanding of the potential ecological consequences. This review describes the fate and impact on marine and freshwater aquatic organisms. Further, we examine the toxicology of MPs in order to uncover the relationship between aquatic organism responses to MPs and ecological disorders. In addition, an overview of the factors that may affect the toxicity effects of MPs on aquatic organisms was presented along with a brief examination of their identification and characterization. MPs were discussed in terms of their physicochemical properties in relation to their toxicological concerns regarding their bioavailability and environmental impact. This paper focuses on the progress of the toxicological studies of MPs on aquatic organisms (bacteria, algae, Daphnia, and fish, etc.) of different trophic levels, and explores its toxic mechanism, such as behavioral alternations, metabolism disorders, immune response, and poses a threat to the composition and stability of the ecosystem. We also review the main factors affecting the toxicity of MPs to aquatic organisms, including direct factors (polymer types, sizes, shapes, surface chemistry, etc.) and indirect factors (persistent organic pollutants, heavy metal ions, additives, and monomer, etc.), and the future research trends of MPs ecotoxicology are also pointed out. The findings of this study will be helpful in guiding future marine and freshwater rubbish studies and management strategies.


Assuntos
Microplásticos , Poluentes Químicos da Água , Animais , Microplásticos/toxicidade , Plásticos/toxicidade , Ecotoxicologia , Ecossistema , Poluentes Químicos da Água/toxicidade , Poluentes Químicos da Água/análise , Organismos Aquáticos , Lagos , Monitoramento Ambiental
11.
Ecotoxicol Environ Saf ; 249: 114431, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36521269

RESUMO

The aquatic system is a major sink for engineered nanomaterials released into the environment. Here, we assessed the toxicity of graphene oxide (GO) using the freshwater planarian Dugesia japonica, an invertebrate model that has been widely used for studying the effects of toxins on tissue regeneration and neuronal development. GO not only impaired the growth of normal (homeostatic) worms, but also inhibited the regeneration processes of regenerating (amputated) worms, with LC10 values of 9.86 mg/L and 9.32 mg/L for the 48-h acute toxicity test, respectively. High concentration (200 mg/L) of GO killed all the worms after 3 (regenerating) or 4 (homeostasis) days of exposure. Whole-mount in situ hybridization (WISH) and immunofluorescence analyses suggest GO impaired stem cell proliferation and differentiation, and subsequently caused cell apoptosis and oxidative DNA damage during planarian regeneration. Mechanistic analysis suggests that GO disturbed the antioxidative system (enzymatic and non-enzymatic) and energy metabolism in the planarian at both molecular and genetic levels, thus causing reactive oxygen species (ROS) over accumulation and oxidative damage, including oxidative DNA damage, loss of mitochondrial membrane integrity, lack of energy supply for cell differentiation and proliferation leading to retardance of neuron regeneration. The intrinsic oxidative potential of GO contributes to the GO-induced toxicity in planarians. These data suggest that GO in aquatic systems can cause oxidative stress and neurotoxicity in planarians. Overall, regenerated tissues are more sensitive to GO toxicity than homeostatic ones, suggesting that careful handling and appropriate decisions are needed in the application of GO to achieve healing and tissue regeneration.


Assuntos
Planárias , Animais , Planárias/genética , Homeostase/fisiologia , Apoptose , Oxirredução , Água Doce
12.
Environ Res ; 204(Pt A): 111903, 2022 03.
Artigo em Inglês | MEDLINE | ID: mdl-34454932

RESUMO

The bacteria (including pathogenic bacteria) attached to road deposited sediments (RDS) may interrelate with the microbe in the atmosphere, soil and water through resuspension and wash-off, and is of great significance to human and ecological health. However, the characteristics of bacterial communities with different time scale on RDS were unknown to dates. Climate change prolonged the dry days between rain events in many areas, making the varied trend of bacterial communities might be more significant in short term. This study revealed the characteristics of bacterial communities on RDS in urban and suburban areas through seasonal and daily scale. The correlations between other factors (land use, particle size, and chemical components) and the bacterial communities were also analyzed. It was found that the season showed a higher association with the bacterial community diversity than land use and particle size in urban areas. The bacterial community diversity increased substantially throughout the short-term study period (41 days) and the variation of dominant bacteria could be fitted by quadratic function in suburbs. In addition, urbanization notably increased the bacterial community diversity, while the potential pathogenic bacteria were more abundant in the suburban areas, coarse RDS (>75 µm), and in spring. The chemical components on RDS showed special correlations with the relative abundance of dominant bacteria. The research findings would fill the knowledge gap on RDS bacterial communities and be helpful for the future research on the assembly process of bacterial communities.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos , Bactérias , Humanos , Chuva , Estações do Ano
14.
Environ Sci Technol ; 55(13): 8654-8664, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34156836

RESUMO

This study compared the impact and uptake of root-administered CeO2 nanoparticles (NPs) in rice growing under flooded and aerobic soil conditions, which are two water regimes commonly used for rice cultivation. CeO2 NPs at 100 mg/kg improved photosynthesis and plant growth by reducing the oxidative damage and enhancing plant tolerance to stress, while a higher concentration (500 mg/kg) of CeO2 NPs negatively affected plant growth. More significant effects were observed under the flooded condition than under the aerobic condition. CeO2 NPs of 100 and 500 mg/kg resulted in 78% and 70% higher accumulation of Ce in shoots under the flooded condition compared to the aerobic condition. CeO2 NPs partially transformed to Ce(III) species in soils and plants under both conditions. A higher extent of transformation under the flooded condition, which was partly attributed to the lower soil pH and redox potential under the flooded condition, leads to higher plant uptake of Ce. A higher extent of transformation in rhizosphere soil was observed. A higher plant transpiration rate (TR) under flooded conditions resulted in a higher accumulation of CeO2 species in shoots. This study, for the first time, reported that water regimes influenced the biotransformation of CeO2 NPs and their uptake and impact in rice plants.


Assuntos
Cério , Nanopartículas , Oryza , Poluentes do Solo , Cério/toxicidade , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade
15.
Environ Sci Technol ; 55(13): 8721-8729, 2021 07 06.
Artigo em Inglês | MEDLINE | ID: mdl-34110809

RESUMO

Reliable chemical identification of specific polymers in environmental samples represents a major challenge in plastic research, especially with the wide range of commercial polymers available, along with variable additive mixtures. Thermogravimetric analysis-Fourier transform infrared-gas chromatography-mass spectrometry (TGA-FTIR-GC-MS) offers a unique characterization platform that provides both physical and chemical properties of the analyzed polymers. This study presents a library of 11 polymers generated using virgin plastics and post-consumer products. TGA inflection points and mass of remaining residues following pyrolysis, in some cases, proved to be indicative of the polymer type. FTIR analysis of the evolved gas was able to differentiate between all but polypropylene (PP) and polyethylene (PE). Finally, GC-MS was able to differentiate between the unique chemical fingerprints of all but one polymer in the library. This library was then used to characterize real environmental samples of mesoplastics collected from beaches in the U.K. and South Africa. Unambiguous identification of the polymer types was achieved, with PE being the most frequently detected polymer and with South African samples indicating variations that potentially resulted from aging and weathering.


Assuntos
Plásticos , Polímeros , Análise de Fourier , Cromatografia Gasosa-Espectrometria de Massas , África do Sul , Espectroscopia de Infravermelho com Transformada de Fourier
16.
Int J Mol Sci ; 22(4)2021 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-33562347

RESUMO

. De novo drug design is a computational approach that generates novel molecular structures from atomic building blocks with no a priori relationships. Conventional methods include structure-based and ligand-based design, which depend on the properties of the active site of a biological target or its known active binders, respectively. Artificial intelligence, including machine learning, is an emerging field that has positively impacted the drug discovery process. Deep reinforcement learning is a subdivision of machine learning that combines artificial neural networks with reinforcement-learning architectures. This method has successfully been employed to develop novel de novo drug design approaches using a variety of artificial networks including recurrent neural networks, convolutional neural networks, generative adversarial networks, and autoencoders. This review article summarizes advances in de novo drug design, from conventional growth algorithms to advanced machine-learning methodologies and highlights hot topics for further development.


Assuntos
Desenho de Fármacos , Aprendizado de Máquina , Redes Neurais de Computação , Preparações Farmacêuticas/química , Animais , Humanos
17.
Molecules ; 26(17)2021 09 01.
Artigo em Inglês | MEDLINE | ID: mdl-34500752

RESUMO

ACEnano is an EU-funded project which aims at developing, optimising and validating methods for the detection and characterisation of nanomaterials (NMs) in increasingly complex matrices to improve confidence in the results and support their use in regulation. Within this project, several interlaboratory comparisons (ILCs) for the determination of particle size and concentration have been organised to benchmark existing analytical methods. In this paper the results of a number of these ILCs for the characterisation of NMs are presented and discussed. The results of the analyses of pristine well-defined particles such as 60 nm Au NMs in a simple aqueous suspension showed that laboratories are well capable of determining the sizes of these particles. The analysis of particles in complex matrices or formulations such as consumer products resulted in larger variations in particle sizes within technologies and clear differences in capability between techniques. Sunscreen lotion sample analysis by laboratories using spICP-MS and TEM/SEM identified and confirmed the TiO2 particles as being nanoscale and compliant with the EU definition of an NM for regulatory purposes. In a toothpaste sample orthogonal results by PTA, spICP-MS and TEM/SEM agreed and stated the TiO2 particles as not fitting the EU definition of an NM. In general, from the results of these ILCs we conclude that laboratories are well capable of determining particle sizes of NM, even in fairly complex formulations.

18.
Proteomics ; 20(9): e1800412, 2020 05.
Artigo em Inglês | MEDLINE | ID: mdl-31750982

RESUMO

Nanomaterials (NMs) are particles with at least one dimension between 1 and 100 nm and a large surface area to volume ratio, providing them with exceptional qualities that are exploited in a variety of industrial fields. Deposition of NMs into environmental waters during or after use leads to the adsorption of an ecological (eco-) corona, whereby a layer of natural biomolecules coats the NM changing its stability, identity and ultimately toxicity. The eco-corona is not currently incorporated into ecotoxicity tests, although it has been shown to alter the interactions of NMs with organisms such as Daphnia magna (D. magna). Here, the literature on environmental biomolecule interactions with NMs is synthesized and a framework for understanding the eco-corona composition and its role in modulating NMs ecotoxicity is presented, utilizing D. magna as a model. The importance of including biomolecules as part of the current international efforts to update the standard testing protocols for NMs, is highlighted. Facilitating the formation of an eco-corona prior to NMs ecotoxicity testing will ensure that signaling pathways perturbed by the NMs are real rather than being associated with the damage arising from reactive NM surfaces "acquiring" a corona by pulling biomolecules from the organism's surface.


Assuntos
Daphnia/efeitos dos fármacos , Daphnia/metabolismo , Nanoestruturas/química , Nanoestruturas/toxicidade , Testes de Toxicidade/métodos , Adsorção , Animais , Feromônios/metabolismo , Poluentes Químicos da Água/química , Poluentes Químicos da Água/farmacocinética , Poluentes Químicos da Água/toxicidade
19.
Anal Chem ; 92(20): 14103-14112, 2020 10 20.
Artigo em Inglês | MEDLINE | ID: mdl-32961048

RESUMO

Capillary zone electrophoresis-mass spectrometry (CE-MS) is a mature analytical tool for the efficient profiling of (highly) polar and ionizable compounds. However, the use of CE-MS in comparison to other separation techniques remains underrepresented in metabolomics, as this analytical approach is still perceived as technically challenging and less reproducible, notably for migration time. The latter is key for a reliable comparison of metabolic profiles and for unknown biomarker identification that is complementary to high resolution MS/MS. In this work, we present the results of a Metabo-ring trial involving 16 CE-MS platforms among 13 different laboratories spanning two continents. The goal was to assess the reproducibility and identification capability of CE-MS by employing effective electrophoretic mobility (µeff) as the key parameter in comparison to the relative migration time (RMT) approach. For this purpose, a representative cationic metabolite mixture in water, pretreated human plasma, and urine samples spiked with the same metabolite mixture were used and distributed for analysis by all laboratories. The µeff was determined for all metabolites spiked into each sample. The background electrolyte (BGE) was prepared and employed by each participating lab following the same protocol. All other parameters (capillary, interface, injection volume, voltage ramp, temperature, capillary conditioning, and rinsing procedure, etc.) were left to the discretion of the contributing laboratories. The results revealed that the reproducibility of the µeff for 20 out of the 21 model compounds was below 3.1% vs 10.9% for RMT, regardless of the huge heterogeneity in experimental conditions and platforms across the 13 laboratories. Overall, this Metabo-ring trial demonstrated that CE-MS is a viable and reproducible approach for metabolomics.


Assuntos
Eletroforese Capilar/métodos , Compostos Orgânicos/sangue , Compostos Orgânicos/urina , Espectrometria de Massas em Tandem/métodos , Cátions/química , Bases de Dados de Compostos Químicos , Eletrólitos/química , Humanos , Metaboloma , Metabolômica , Reprodutibilidade dos Testes
20.
Small ; 16(36): e2003691, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32780948

RESUMO

In aquatic environments, a large number of ecological macromolecules (e.g., natural organic matter (NOM), extracellular polymeric substances (EPS), and proteins) can adsorb onto the surface of engineered nanomaterials (ENMs) to form a unique environmental corona. The presence of environmental corona as an eco-nano interface can significantly alter the bioavailability, biocompatibility, and toxicity of pristine ENMs to aquatic organisms. However, as an emerging field, research on the impact of the environmental corona on the fate and behavior of ENMs in aquatic environments is still in its infancy. To promote a deeper understanding of its importance in driving or moderating ENM toxicity, this study systemically recapitulates the literature of representative types of macromolecules that are adsorbed onto ENMs; these constitute the environmental corona, including NOM, EPS, proteins, and surfactants. Next, the ecotoxicological effects of environmental corona-coated ENMs on representative aquatic organisms at different trophic levels are discussed in comparison to pristine ENMs, based on the reported studies. According to this analysis, molecular mechanisms triggered by pristine and environmental corona-coated ENMs are compared, including membrane adhesion, membrane damage, cellular internalization, oxidative stress, immunotoxicity, genotoxicity, and reproductive toxicity. Finally, current knowledge gaps and challenges in this field are discussed from the ecotoxicology perspective.


Assuntos
Ecotoxicologia , Nanoestruturas , Coroa de Proteína , Nanoestruturas/toxicidade , Coroa de Proteína/química
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