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1.
Sci Total Environ ; 752: 142000, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-32889254

RESUMO

The presence of pharmaceuticals and personal care products (PPCPs) in water remains a concern due to their potential threat to environmental and human health. Advanced oxidation processes (AOPs) have been receiving attention in water treatment studies to remove PPCPs. However, most studies have been focused on pure water containing a limited number of substances. In this study, the photocatalytic efficiency of commercially available titanium dioxide nanoparticles (P25) and P25 modified by silver nanoparticles (Ag-P25) were compared for their ability to degrade 23 target PPCPs (2 µg L-1) in realistic water matrices containing natural organic matter (Suwanee River NOM, 6.12 mg L-1). The experiments were completed under ultraviolet-light emitting diode (UV-LED) illumination at 365 and 405 nm wavelengths, with the latter representing visible light exposure. Under 365 nm UV-LED treatment, 99% of the PPCPs were removed using both P25 and Ag-P25 photocatalysts within 180 min of the treatment duration. The number of PPCPs removed dropped to 57% and 53% for P25 and Ag-P25 respectively under the 405 nm UV-LED irradiation. Dissolved organic carbon (DOC) and UV absorbance at 254 nm (UV254) measured at the end of the experiment indicated that the aromatic fraction of NOM was preferentially removed from the water matrix. Also, Ag-P25 was more effective in DOC removal than P25. The relationships of removal rate constants with physico-chemical properties of the substances were also determined. The molecular weight and charge were strongly associated with removal, with the former and the latter being positively and negatively correlated with the rate constants. The results of this work indicate that Ag-P25 is a promising photocatalyst to degrade persistent substances such as PPCPs and NOM even if they are present in a complex water matrix. The properties of individual substances can also be employed as an indication of their removal using this technology.


Assuntos
Cosméticos , Nanopartículas Metálicas , Preparações Farmacêuticas , Poluentes Químicos da Água , Purificação da Água , Prata , Poluentes Químicos da Água/análise
2.
Sci Total Environ ; 753: 141743, 2021 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-32891989

RESUMO

Nickel oxide nanoparticles (NiO-NPs) have extensively used in industrial and consumer products. The present study conducted to gain more knowledge about the safe use of NiO-NPs and also to understand their impact on the environment and biological systems. Herein, we examined the genotoxic and ultra-structural effects of a sublethal dose of NiO-NPs (0.03 mg/g) on the ovarian tissues of the ground beetle, Blaps polycresta. The mean diameter of NiO-NPs was 24.49 ± 3.88 nm, as obtained through transmission electron microscopy (TEM). In terms of DNA damage levels, the frequency of micronucleus (MN) formation was highly significant in the NiO-NPs treated group versus the controls. Besides, NiO-NPs treatment resulted in a significant increase in the tail length of comets. Further, electron microscopy revealed a progressive increase in chromatin condensation of the ovarian nurse and follicular cells, in addition to the accumulation of lysosomes and endo-lysosomes in their cytoplasm. In conclusion, NiO-NPs are capable of gaining access to the ovary of B. polycresta and causing DNA damage and a high degree of cellular toxicity in the ovarian cells. The present study highlights, for the first time, the adverse effects of these NPs to female gonads of insects and raised the concern of its genotoxic potential. It would be of interest to investigate NiO-NPs mediated intracellular ROS generation in future studies.


Assuntos
Besouros , Nanopartículas Metálicas , Nanopartículas , Animais , Dano ao DNA , Feminino , Nanopartículas Metálicas/toxicidade , Níquel/toxicidade
3.
Food Chem ; 336: 127634, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32777654

RESUMO

Bilayer colorimetric films were developed for monitoring fish spoilage by using gelatin (GN) incorporated with ZnO nanoparticles as the upper layer (GN-ZnO), and gellan gum (GG) incorporated with mulberry anthocyanins (MBA) as the lower layer (GG-MBA). The color stability of the bilayer colorimetric films under visible and ultraviolet light was improved with the increase of ZnO nanoparticles content. Meanwhile, the bilayer films had good NH3 sensitivity. The limit of detection of the GG-MBA/GN-2.0% ZnO film to NH3 was 0.01 mM. The electrochemical writing ability of the bilayer films was also identified, indicating the feasibility of inks-free printing on biopolymer films. Finally, the GG-MBA/GN-2.0% ZnO film with an electrochemical writing pattern was used to monitor crucian spoilage. The GG-MBA/GN-2.0% ZnO film with electrochemical writing pattern showed visible color changes with the crucian spoilage. In conclusion, the bilayer colorimetric film was expected to be a good fish spoilage indicator in smart packaging.


Assuntos
Embalagem de Alimentos/métodos , Inocuidade dos Alimentos , Luz , Animais , Antocianinas/química , Cor , Produtos Pesqueiros/análise , Embalagem de Alimentos/instrumentação , Gelatina/química , Concentração de Íons de Hidrogênio , Nanopartículas Metálicas/química , Morus/química , Morus/metabolismo , Polissacarídeos Bacterianos/química , Resistência à Tração , Óxido de Zinco/química
4.
Food Chem ; 336: 127710, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32763739

RESUMO

Conventional gold nanoparticle-based lateral flow immunoassay (LFIA) usually suffers a huge challenge in measuring target concentration in food matrices with dark color because of its poor resistance to the background matrix and color interference. To address this issue, we first report a novel bifunctional magneto-gold nanohybrid (MGNH) for the simultaneous magnetic separation and colorimetric target sensing by integrating MGNHs into LFIA. Under optimum conditions, an ultrasensitive detection of ochratoxin A (OTA) in grape juice was achieved with a limit of detection at 0.094 ng mL-1. The average recoveries of this MGNH-LFIA ranged from 92.31% to 108.97% with a coefficient of variation of below 12%. The excellent selectivity of our MGNH-LFIA against OTA was demonstrated. Besides, our MGNH-LFIA is comparable to liquid chromatography coupled with mass spectrometry in terms of accuracy, reproducibility, and practicability. The designed MGNH-LFIA platform is readily extended for improving other small molecule detection in food samples.


Assuntos
Contaminação de Alimentos/análise , Sucos de Frutas e Vegetais/análise , Imunoensaio/métodos , Nanopartículas Metálicas/química , Ocratoxinas/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Ouro/química , Imunoensaio/instrumentação , Limite de Detecção , Fenômenos Magnéticos , Ocratoxinas/imunologia , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Espectrofotometria Ultravioleta , Vitis/química
5.
Food Chem ; 336: 127713, 2021 Jan 30.
Artigo em Inglês | MEDLINE | ID: mdl-32768909

RESUMO

The presence of multiple mycotoxins in the agricultural products poses a serious threat to the health of humans and animals. Citrinin (CIT) causes slow growth in animals and damages the kidney function. Zearalenone (ZEN) causes chronic poisoning, abnormal functioning and even death in animals. Herein, a dual fluorescent immunochromatographic assay (DF-ICA) based on europium nanoparticles (EuNPs) was developed for the simultaneous detection of CIT and ZEN in the corn samples. After optimization, the limits of detection (LODs), IC50 and average recoveries for the simultaneous determination of CIT and ZEN were 0.06 and 0.11 ng/mL, 0.35 and 0.76 ng/mL, from 86.3% to 111.6% and from 86.6% to 114.4%, respectively. Moreover, the DF-ICA was validated by high performance liquid chromatography (HPLC) analyses, and a satisfactory consistency was obtained. In brief, this work demonstrates the feasibility of DF-ICA for simultaneous monitoring of CIT and ZEN in the corn samples.


Assuntos
Citrinina/análise , Contaminação de Alimentos/análise , Imunoensaio/métodos , Zea mays/química , Zearalenona/análise , Animais , Anticorpos Monoclonais/química , Anticorpos Monoclonais/imunologia , Cromatografia Líquida de Alta Pressão , Citrinina/imunologia , Európio/química , Fluorescência , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Reprodutibilidade dos Testes , Sensibilidade e Especificidade , Zearalenona/imunologia
6.
Food Chem ; 338: 127796, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32805691

RESUMO

Trace detection of toxic chemicals in foodstuffs is of great concern in recent years. Surface-enhanced Raman scattering (SERS) has drawn significant attention in the monitoring of food safety due to its high sensitivity. This study synthesized signal optimized flower-like silver nanoparticle-(AgNP) with EF at 25 °C of 1.39 × 106 to extend the SERS application for pesticide sensing in foodstuffs. The synthesized AgNP was deployed as SERS based sensing platform to detect methomyl, acetamiprid-(AC) and 2,4-dichlorophenoxyacetic acid-(2,4-D) residue levels in green tea via solid-phase extraction. A linear correlation was twigged between the SERS signal and the concentration for methomyl, AC and 2,4-D with regression coefficient of 0.9974, 0.9956 and 0.9982 and limit of detection of 5.58 × 10-4, 1.88 × 10-4 and 4.72 × 10-3 µg/mL, respectively; the RSD value < 5% was recorded for accuracy and precision analysis suggesting that proposed method could be deployed for the monitoring of methomyl, AC and 2,4-D residue levels in green tea.


Assuntos
Contaminação de Alimentos/análise , Nanopartículas Metálicas/química , Resíduos de Praguicidas/análise , Análise Espectral Raman/métodos , Chá/química , Ácido 2,4-Diclorofenoxiacético/análise , Análise de Alimentos/instrumentação , Análise de Alimentos/métodos , Metomil/análise , Neonicotinoides/análise , Prata/química , Extração em Fase Sólida
7.
Food Chem ; 337: 127990, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32919272

RESUMO

A very practical and competitive sensing strategy for the detection of azodicarbonamide in flour samples was developed by using label-free Ag NPs as a colorimetric probe. Well-dispersed Ag NPs in suspension can form aggregates upon reacting with glutathione (GSH) via Ag-SH covalent bonds and electrostatic attraction, with the color changing from bright yellow to red. However, azodicarbonamide can oxidize the -SH of GSH, preventing the aggregation of Ag NPs. Under the optimum conditions, the A550/A398 of Ag NPs is linearly related to the concentration of azodicarbonamide in the range of 0.33 µM to 1.7 µM. The proposed method can be used for the detection of azodicarbonamide in flour, with a detection limit of 0.09 µM and recovery between 95% and 97.4% (RSD < 6%). When the azodicarbonamide concentration reaches 0.33 µM, the color change can be detected by the naked eye.


Assuntos
Compostos Azo/análise , Colorimetria/métodos , Farinha/análise , Análise de Alimentos/métodos , Nanopartículas Metálicas/química , Cor , Aditivos Alimentares/análise , Análise de Alimentos/instrumentação , Glutationa/química , Prata/química
8.
Food Chem ; 337: 127978, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32920268

RESUMO

Aflatoxin B1 (AFB1) contamination causes huge economic losses. To explore the correlation between catalase (CAT) and AFB1 production during fungal development, we fabricated an electrochemical CAT-activity sensor by measuring residual H2O2 after enzymatic degradation. The sensor made by palladium nanoparticles/carbonized bacterial cellulose nanocomposites exhibits a linear range over 0.5-3.5 U/mL and a detection limit of 0.434 U/mL. Both dry weight and CAT activity of mycelia continuously increase. But, the latter shows a greater increase than the former after three days. Specific CAT activity in crude enzyme extract of A. flavus was quantified. It maintains at ~25.00 U/mg for 3 days and enhances to 28.91 and 45.30 U/mg, respectively, on days 4 and 5. AFB1 production follows the same trend. On days 4 and 5, AFB1 concentration reaches 201.35 and 767.9 ng/mL, respectively. The positive correlation between specific CAT activity and AFB1 production suggests that CAT is involved in AFB1 biosynthesis.


Assuntos
Aflatoxina B1/biossíntese , Aspergillus flavus/crescimento & desenvolvimento , Aspergillus flavus/metabolismo , Catalase/análise , Técnicas Eletroquímicas/métodos , Aflatoxina B1/análise , Catalase/metabolismo , Cromatografia Líquida de Alta Pressão , Técnicas Eletroquímicas/instrumentação , Proteínas Fúngicas/análise , Proteínas Fúngicas/metabolismo , Peróxido de Hidrogênio/análise , Peróxido de Hidrogênio/metabolismo , Limite de Detecção , Nanopartículas Metálicas/química , Microscopia Eletrônica de Transmissão , Micélio/química , Micélio/metabolismo , Paládio/química , Difração de Raios X
9.
Food Chem ; 337: 127652, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32799158

RESUMO

Deltamethrin, one of the most toxic pyrethroids, is commonly used to inhibit pests in wheat. However, the trace levels of deltamethrin in wheat is alarming to human health. In this study, surface-enhanced Raman spectroscopy (SERS)-active silver nanoparticles-plated-zinc oxide nanoflowers (Ag@ZnO NFs) nano-sensor were employed for rapid and sensitive quantification of deltamethrin in wheat. To sufficiently utilize the chemical-related information in SERS spectra, various spectral pretreatment and chemometric models were studied. The mean centering (MC) coupling successive projection algorithm-partial least squares regression (SPA-PLS) provided optimal predictive performance (correlation coefficient of prediction (Rp) = 0.9736 and residual predictive deviation (RPD) = 4.75). The proposed method achieved the limit of detection (LOD) = 0.16 µg·kg-1, the recovery of predicted results was in the range of 96.33-109.17% and the relative standard deviation (RSD) was < 5%. The overall results suggested that SERS based Ag@ZnO NFs combined with MC-SPA-PLS could be an easy and efficient method to quantify deltamethrin residue levels in wheat.


Assuntos
Análise de Alimentos/métodos , Contaminação de Alimentos/análise , Nitrilos/análise , Piretrinas/análise , Análise Espectral Raman/métodos , Triticum/química , Análise de Alimentos/estatística & dados numéricos , Análise dos Mínimos Quadrados , Limite de Detecção , Nanopartículas Metálicas/química , Resíduos de Praguicidas/análise , Prata/química , Óxido de Zinco/química
10.
Sci Total Environ ; 752: 142264, 2021 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-33207511

RESUMO

Green synthesis of silver nanoparticles (Ag NPs) by using plants extracts has provided an eco-friendly alternation for industry and agriculture application. Here, we prepared Ag NPs by using the cucumber leaves and rice husk extracts, and further assessed the antimicrobial activity and phytotoxicity of green synthesized Ag NPs (g-Ag NPs) comparing with chemically synthesized Ag NPs (chem-Ag NPs). The chem-Ag NPs had strong antibacterial activity on the growth of Escherichia coli, while g-Ag NPs by rice husks (gr-Ag NPs) exhibited long-term antibacterial effects. In terms of phytotoxicity, the chem-Ag NPs induced over-generation of ROS and activated plant antioxidant defense systems, thus resulting in the upregulation of MDA and Zn contents and downregulation of antioxidant capacity, carotenoid, globulin and Mo contents. However, g-Ag NPs significantly promoted cucumber photosynthesis by increasing chlorophyll contents. Besides, the green synthesized Ag NPs by cucumber extracts (gc-Ag NPs) increased protein contents and gr-Ag NPs stimulated the upregulation of Mn and the downregulation of Al, which were all positive effects. Overall, compared with chem-Ag NPs, g-Ag NPs exhibited long-tern antimicrobial properties and attenuated toxicity to plants, which could be used as potential nanopesticide or nanoscale growth regulator in agriculture.


Assuntos
Anti-Infecciosos , Nanopartículas Metálicas , Antibacterianos/toxicidade , Química Verde , Nanopartículas Metálicas/toxicidade , Testes de Sensibilidade Microbiana , Extratos Vegetais/toxicidade , Prata/toxicidade
11.
Food Chem ; 337: 127761, 2021 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-32777565

RESUMO

Amino and thiolated aptamers are the main aptamers used to construct label-free electrochemical impedimetric aptasensors. In this study, the modification performance and electrochemical properties of amino aptamers and thiolated aptamers were studied in the construction of label-free impedimetric sensors. The results showed that the initial modification density of amino aptamers was higher than that of thiol aptamers. Aptamers can recognize and bind OTA to generate electrical signals. The higher the density of aptamer modification was, the better the electric signals were. If only considering the initial modification density, amino aptamers were more suitable for the preparation of aptasensors than thiolated aptamers. However, the modification density of the amino aptamer decreased with the prolonged immersion time in 1 mM HCl solution, which suggests that the stability of this sensor was poor. However, the thiolated aptamer maintained relatively constant density and could be reused. Thus, the thiolated aptasensor had a wide range and good reproducibility and stability for the determination of ochratoxin A (OTA). In addition, this study proved that gold nanoparticles play an important role in signal amplification by increasing the effective gold surface to fix more aptamers in the process of sensor preparation.


Assuntos
Aptâmeros de Nucleotídeos/química , Aptâmeros de Nucleotídeos/metabolismo , Técnicas Biossensoriais/métodos , Impedância Elétrica , Eletroquímica , Eletrodos , Ouro/química , Nanopartículas Metálicas/química , Ocratoxinas/análise , Reprodutibilidade dos Testes
12.
Food Chem ; 338: 127787, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-32827901

RESUMO

A rapid colorimetric method using cysteine-modified silver nanoparticles (Cys-AgNPs) is applied for the detection of 3-monochloropropane-1,2-diol (3-MCPD). Indeed, in the presence of 3-MCPD, the color of Cys-AgNPs solution changes from yellow to pink within five minutes at 100 °C and pH 9.3. This change is mainly attributed to the ability of amino group of cysteine to react with 3-MCPD to form N-(2,3-dihydroxypropyl)-amino acid grafted on AgNPs (3-MCPD-Cys-AgNPs) in alkaline medium. This color change makes 3-MCPD to be clearly detectable by unassisted visual means even at 0.1 µg⋅mL-1. Besides, using UV-Vis spectroscopic technique, a linear range from 0.1 µg⋅mL-1 to 1.25 µg⋅mL-1 for 3-MCPD detection is obtained, with a calculated detection limit of 0.084 µg⋅mL-1. These results suggest that this sensing technique is sensitive to 3-MCPD and may have a substantial application in the rapid detection of food contaminants particularly, where quality and safety of food products are paramount concern.


Assuntos
Cisteína/química , Análise de Alimentos/métodos , Nanopartículas Metálicas/química , Prata/química , alfa-Cloridrina/análise , Colorimetria , Contaminação de Alimentos/análise , Fatores de Tempo , alfa-Cloridrina/isolamento & purificação
13.
Biosens Bioelectron ; 171: 112731, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33075725

RESUMO

Rapid person-to-person transfer of viruses such as SARS-CoV-2 and their occasional mutations owing to the human activity and climate/ecological changes by the mankind led to creation of wrecking worldwide challenges. Such fast transferable pathogens requiring practical diagnostic setups to control their transfer chain and stop sever outbreaks in early stages of their appearance. Herein, we have addressed this urgent demand by designing a rapid electrochemical diagnostic kit composed of fixed/screen printed electrodes that can detect pathogenic viruses such as SARS-CoV-2 and/or animal viruses through the differentiable fingerprint of their viral glycoproteins at different voltage positions. The working electrode of developed sensor is activated upon coating a layer of coupled graphene oxide (GO) with sensitive chemical compounds along with gold nanostars (Au NS) that can detect the trace of viruses in any aquatic biological media (e.g., blood, saliva and oropharyngeal/nasopharyngeal swab) through interaction with active functional groups of their glycoproteins. The method do not require any extraction and/or biomarkers for detection of target viruses and can identify trace of different pathogenic viruses in about 1 min. The nanosensor also demonstrated superior limit of detection (LOD) and sensitivity of 1.68 × 10-22 µg mL-1 and 0.0048 µAµg.mL-1. cm-2, respectively, toward detection of SARS-CoV-2 in biological media, while blind clinical evaluations of 100 suspected samples furtherly confirmed the superior sensitivity/specificity of developed nanosystem toward rapid identification of ill people even at incubation and prodromal periods of illness.


Assuntos
Betacoronavirus/isolamento & purificação , Técnicas de Laboratório Clínico , Infecções por Coronavirus/diagnóstico , Técnicas Eletroquímicas/instrumentação , Pneumonia Viral/diagnóstico , Glicoproteína da Espícula de Coronavírus/análise , Animais , Técnicas Biossensoriais/instrumentação , Eletrodos , Desenho de Equipamento , Ouro/química , Grafite/química , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Pandemias
14.
Biosens Bioelectron ; 171: 112753, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33120235

RESUMO

A polyethyleneimine (PEI)-assisted copper in-situ growth (CISG) strategy was proposed as a controlled signal amplification strategy to enhance the sensitivity of gold nanoparticle-based lateral flow sensors (AuNP-LFS). The controlled signal amplification is achieved by introducing PEI as a structure-directing agent to regulate the thermodynamics of anisotropic Cu nanoshell growth on the AuNP surface, thus controlling shape and size of the resultant AuNP@Cu core-shell nanostructures and confining free reduction and self-nucleation of Cu2+ for improved reproducibility and decreased false positives. The PEI-CISG-enhanced AuNP-LFS showed ultrahigh sensitivities with the detection limits of 50 fg mL-1 for HIV-1 capsid p24 antigen and 6 CFU mL-1 for Escherichia coli O157:H7. We further demonstrated its clinical diagnostic efficacy by configuring PEI-CISG into a commercial AuNP-LFS detection kit for SARS-CoV-2 antibody detection. Altogether, this work provides a reliable signal amplification platform to dramatically enhance the sensitivity of AuNP-LFS for rapid and accurate diagnostics of various infectious diseases.


Assuntos
Técnicas Biossensoriais/métodos , Cobre/química , Infecções por Coronavirus/diagnóstico , Infecções por Escherichia coli/diagnóstico , Ouro/química , Infecções por HIV/diagnóstico , Pneumonia Viral/diagnóstico , Betacoronavirus/isolamento & purificação , Técnicas Biossensoriais/instrumentação , Técnicas de Laboratório Clínico , Desenho de Equipamento , Escherichia coli O157/isolamento & purificação , Proteína do Núcleo p24 do HIV/análise , HIV-1/isolamento & purificação , Humanos , Limite de Detecção , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Oxirredução , Pandemias , Polietilenoimina/química , Fitas Reagentes/análise
15.
Sci Total Environ ; 750: 141303, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-32871366

RESUMO

Silver nanoparticles (Ag NPs) are present in numerous consumer products due to their antimicrobial and other unique properties, thus concerns about their potential input into aquatic ecosystems are increasing. Toxicity of Ag NPs in waterborne exposed aquatic organisms has been widely investigated, but studies assessing the potential toxic effects caused after ingestion through the food web, especially at low realistic concentrations, remain scarce. Moreover, it is not well known whether season may influence toxic effects of Ag NPs. The main objective of this study was to determine cell and tissue level responses in mussels Mytilus galloprovincialis dietarily exposed to poly-N-vinyl-2-pirrolidone/polyethyleneimine (PVP/PEI) coated 5 nm Ag NPs for 1, 7 and 21 days both in autumn and spring. Mussels were fed every day with microalgae Isochrysis galbana exposed for 24 h to a low dose (1 µg Ag/L Ag NPs) in spring and to a higher dose (10 µg Ag/L Ag NPs) in spring and autumn. Mussels fed with microalgae exposed to the high dose accumulated Ag significantly after 21 days in both seasons, higher levels being measured in autumn compared to spring. Intralysosomal metal accumulation measured in mussel digestive gland and time- and dose-dependent reduction of mussels health status was similar in both seasons. DNA strand breaks increased significantly in hemocytes at both exposure doses along the 21 days in spring and micronuclei frequency showed an increasing trend after 1 and 7 days of exposure to 1 µg Ag/L Ag NPs in spring and to 10 µg Ag/L in both seasons. Values decreased after 21 days of exposure in all the cases. In conclusion, PVP/PEI coated 5 nm Ag NPs ingested through the food web were significantly accumulated in mussel tissues and caused adverse cell and tissue level effects both in autumn and in spring.


Assuntos
Nanopartículas Metálicas , Mytilus , Poluentes Químicos da Água , Animais , Ecossistema , Nanopartículas Metálicas/toxicidade , Estações do Ano , Prata/toxicidade
16.
Chemosphere ; 262: 127805, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32750593

RESUMO

The present study assessed the individual and combined toxicity effects of Ag- and TiO2- nanoparticles (NPs) on Ag bioaccumulation, oxidative stress, and gill histopathology in common carp as an aquatic animal model. The 96-h acute toxicity tests showed that TiO2NPs enhanced the toxicity of AgNPs deducted from the decreased LC50 in co-exposure to these NPs. Chronic toxicity tests included a 10-day exposure and a 10-day recovery period. In most cases, histological damages were more severe in co-exposure to Ag- and TiO2- NPs compared with the individual AgNPs however, they were reduced in some cases and also after the recovery period. In co-exposure to Ag- and TiO2- NPs, the Ag bioaccumulation was decreased in the gills but increased in the liver and intestine compared with the singular exposure. After the recovery period, Ag bioaccumulation decreased especially in the liver. Decreased levels of antioxidant enzymes were observed in the AgNPs exposed groups, which were partially alleviated by TiO2NPs. The reduction of condition factor (CF) and hepatosomatic index (HSI) and a severe decrease of weight gain (WG) were observed in co-exposure to Ag- and TiO2- NPs. After the recovery period, the CF and HSI increased but the WG decreased less compared with the exposure period. The present results emphasize the importance of considering the co-existence and interaction of NPs in realizing their bioavailability and toxicity in aquatic environments.


Assuntos
Carpas/fisiologia , Nanopartículas Metálicas/toxicidade , Titânio/química , Poluentes Químicos da Água/toxicidade , Animais , Antioxidantes/metabolismo , Brânquias , Dose Letal Mediana , Fígado/metabolismo , Nanopartículas/toxicidade , Estresse Oxidativo , Prata/toxicidade
17.
Mar Pollut Bull ; 160: 111665, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33181940

RESUMO

In vitro methods have gained rising importance in ecotoxicology due to ethical concerns. The aim of this study was to assess the single and combined in vitro effects of gold, as nanoparticle (AuNPs) and ionic (Au+) form, and the pharmaceutical gemfibrozil (GEM). Sparus aurata liver organ culture was exposed to gold (4 to 7200 µg·L-1), GEM (1.5 to 15,000 µg·L-1) and combination 80 µg·L-1 gold +150 µg·L-1 GEM for 24 h. Endpoints related with antioxidant status, peroxidative/genetic damage were assessed. AuNPs caused more effects than Au+, increasing catalase and glutathione reductase activities and damaging DNA and cellular membranes. Effects were dependent on AuNPs size, coating and concentration. GEM damaged DNA at an environmentally relevant concentration, 1.5 µg·L-1. Overall, the effects of the combined exposures were higher than the predicted, based on single exposures. This study showed that liver culture can be a useful model to study contaminants effects.


Assuntos
Nanopartículas Metálicas , Dourada , Animais , Genfibrozila/toxicidade , Ouro , Fígado , Nanopartículas Metálicas/toxicidade , Técnicas de Cultura de Órgãos
18.
Water Sci Technol ; 82(9): 1912-1920, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33201854

RESUMO

The formation of heterojunction structures of semiconductors is one of the most important techniques to increase the photocatalytic efficiency of a photocatalyst. In this paper, Ag/Ag3VO4/TiO2 as a visible light response photocatalyst was prepared easily by a three step process including hydrothermal, precipitation and photoreduction. The Ag/Ag3VO4/TiO2 nanocomposites demonstrated clearly increased visible light absorption and photocatalytic efficiency in degradation of Rhodamine B. The degradation yield of Rhodamine B was detected 97.3% in 45 min under visible light. Compared with Ag3VO4, TiO2 and Ag3VO4/TiO2, Ag/Ag3VO4/TiO2 exhibited the highest efficiency owing to synergetic effect between Ag3VO4 and TiO2 and surface plasmon resonance effect of Ag nanoparticles. So, the Ag/Ag3VO4/TiO2 can be effectively used as an active photocatalyst under visible light and it depicts an ideal potential in elimination organic pollutants.


Assuntos
Poluentes Ambientais , Nanopartículas Metálicas , Catálise , Luz , Prata , Titânio
19.
J Biomed Nanotechnol ; 16(6): 853-866, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33187581

RESUMO

The mitochondria have recently become a novel target in the treatment of cancer. Targeted delivery by nanoparticles (NPs) has shown potential in enhancing existing therapeutic principles. With toxicity remaining a recurring issue, the green synthesis of inorganic NPs and modification with polymers may help to improve stability and biocompatibility. We synthesized epigallocatechin gallate (EGCG)-capped gold NPs (AuNPs), and functionalized with poly-D-lysine grafted polyethylene glycol (PDL-g-PEG), and the mitochondrial targeting triphenylphosphonium cation, and thereafter assessed their mitochondrial delivery capacity of paclitaxel in cancer cells in vitro. This PDL-g-PEG coated EGCG-AuNPs were further assessed for their laminin receptor avidity and mitochondrial localisation potential, upon functionalisation with the delocalised cation, triphenylphosphine. The laminin receptor dependent uptake and mitochondrial localisation of targeted T-Au(PDL-g-PEG) NPs were confirmed by ICP-OES and fluorescent microscopy. Their delivery of paclitaxel to the mitochondria of cancer cells elicited significant cytotoxicity especially in the human cervical carcinoma (HeLa) cell line, compared to the untargeted T-Au(PDL-g-PEG) and free drugs. Mechanistic studies implicated caspase dependent apoptosis as the mechanism of cell death. Our findings demonstrate the capacity of T-Au-[PDL-PEG] NPs to preferentially localize in the tumour mitochondria, and confirms the potential impact of subcellular targeting, especially to the mitochondria in cancer cells for an improvement in the therapeutic indices of these drugs.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Linhagem Celular Tumoral , Sistemas de Liberação de Medicamentos , Feminino , Ouro , Humanos , Mitocôndrias , Recidiva Local de Neoplasia , Polietilenoglicóis , Polímeros
20.
J Biomed Nanotechnol ; 16(6): 985-996, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33187593

RESUMO

Cetuximab-conjugated gold nanoparticles are known to target cancer cells, but display toxicity towards normal kidney, liver and endothelial cells in vitro. In this study, we investigated their pharmacokinetics, biodistribution and toxicity after intravenous administration in healthy mice. Our data showed that these nanoparticles were rapidly cleared from the blood and accumulated mainly in the liver and spleen with long-term retention. Acute liver injury, inflammatory activity and vascular damage were transient and negligible, as confirmed by the liver functionality tests and serum marker analysis. There was no sign of altered liver, kidney, lung and spleen morphology up to 4 weeks post-injection. After 6 months, kidney casts and splenic apoptosis appeared to be more prevalent than in the controls. Furthermore, occasional immune cell infiltration was observed in the lungs. Therefore, we recommend additional in vivo studies, in order to investigate the long-term toxicity and elimination of gold nanoparticles after multiple dosing in their preclinical validation as new targeted anti-cancer therapies.


Assuntos
Nanopartículas Metálicas , Nanopartículas , Animais , Células Endoteliais , Ouro/metabolismo , Ouro/toxicidade , Nanopartículas Metálicas/toxicidade , Camundongos , Baço/metabolismo , Distribuição Tecidual
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