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1.
Ecotoxicol Environ Saf ; 189: 109982, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31830603

RESUMO

The increasing application of nanomaterials in various fields such as drug delivery, cosmetics, disease detection, cancer treatment, food preservation etc. has resulted in high levels of engineered nanoparticles in the environment, thus leading to higher possibility of direct or indirect interactions between these particles and biological systems. In this study, the toxic effects of three commercially available nanomaterials; copper oxide nanoparticles, copper-iron oxide nanopowders and carbon nanopowders were determined in the human hepatoma HepG2 cells using various toxicological assays which are indicative of cytotoxicity (MTT and neutral red assays), mutagenicity (cytokinesis-block micronucleus assay), oxidative stress (total reactive oxygen species and superoxide anion production) and mitochondrial impairment (cellular oxygen consumption). There was increased cytotoxicity, mutagenicity, and mitochondrial impairment in the cells treated with higher concentrations of the nanomaterials, especially the copper oxide nanoparticles. The fold production of reactive oxygen species was similar at the concentrations tested in this study but longer exposure duration resulted in production of more superoxide anions. The results of this study showed that copper oxide nanoparticles are highly toxic to the human HepG2 cells, thus implying that the liver is a target organ in human for copper oxide nanoparticles toxicity.


Assuntos
Carbono/toxicidade , Cobre/toxicidade , Poluentes Ambientais/toxicidade , Compostos Ferrosos/toxicidade , Nanopartículas/toxicidade , Carbono/química , Cobre/química , Dano ao DNA/efeitos dos fármacos , Poluentes Ambientais/química , Compostos Ferrosos/química , Células Hep G2 , Humanos , Mitocôndrias/efeitos dos fármacos , Nanopartículas/química , Estresse Oxidativo/efeitos dos fármacos
2.
Mikrochim Acta ; 186(12): 851, 2019 11 27.
Artigo em Inglês | MEDLINE | ID: mdl-31776683

RESUMO

A rapid, sensitive, and selective fluorometric assay is described for the determination of chromium(VI) in real waters and living cells. The method is making use of nitrogen, phosphorus, and sulfur tri-doped carbon dots (NPS-CDs) which have absorption/emission maxima at 360/505 nm/nm. Cr(VI) has an absorption maximum at 350 nm and causes an inner filter effect (IFE) on the blue fluorescence of the NPS-CDs. The NPS-CDs were hydrothermally synthesized using p-aminobenzenesulfonic acid and tetrakis(hydroxymethyl)phosphonium chloride as precursors. The NPS-CDs were characterized by transmission electron microscopy, X-ray diffraction, and several spectroscopic methods. They are biocompatible and negligibly cytotoxic when tested with HeLa cells and MCF-7 cells even after 48 h of incubation. The NPS-CDs were used as fluorescent probes for Cr(VI). The detection limit is 0.23 µM (three times standard deviation versus slope), and the linear response covers the 1 to 500 µM chromate concentration range. The NPS-CDs were applied to the determination of Cr(VI) in real waters and living cells (HeLa and MCF-7) and gave satisfying results. Graphical abstractSchematic representation of hydrothermal synthesis of nitrogen, phosphorus, and sulfur tri-doped carbon dots (NPS-CDs) for Cr(VI) detection via inner filter effect (IFE). NPS-CDs were applied to the determination of Cr(VI) in living cells (HeLa and MCF-7) with satisfying results.


Assuntos
Cromo/análise , Corantes Fluorescentes/química , Pontos Quânticos/química , Poluentes Químicos da Água/análise , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Água Potável/análise , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Lagos/análise , Limite de Detecção , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Nitrogênio/química , Nitrogênio/toxicidade , Fósforo/química , Fósforo/toxicidade , Pontos Quânticos/toxicidade , Chuva/química , Rios/química , Espectrometria de Fluorescência/métodos , Enxofre/química , Enxofre/toxicidade , Águas Residuárias/análise
3.
Artigo em Inglês | MEDLINE | ID: mdl-31771182

RESUMO

As a non-invasive method, heart rate variability (HRV) has been widely used to study cardiovascular autonomous control. Environmental epidemiological studies indicated that the increase in an average concentration of particulate matter (PM) would result in a decrease in HRV, which was related to the increase of cardiovascular mortality in patients with myocardial infarction and the general population. With rapid economic and social development in Asia, how air pollutants, such as PM of different sizes and their components, affect the cardiovascular health of older people, still need to be further explored. The current study includes a 72 h personal exposure monitoring of seven healthy older people who lived in the Taipei metropolitan area. Mobile equipment, a portable electrocardiogram recorder, and the generalized additive mixed model (GAMM) were adopted to evaluate how HRV indices were affected by size-fractionated PM, particle-bound polycyclic aromatic hydrocarbons (p-PAHs), black carbon (BC), and carbon monoxide (CO). Other related confounding factors, such as age, sex, body mass index (BMI), temperature, relative humidity (RH), time, and monitoring week were controlled by fixed effects of the GAMM. Statistical analyses of multi-pollutant models showed that PM2.5-10, PM1, and nanoparticle (NP) could cause heart rate (HR), time-domain indices, and frequency-domain indices to rise; PM1-2.5 and BC would cause the frequency-domain index to rise; p-PAHs would cause HR to rise, and CO would cause time-domain index and frequency-domain index to decline. In addition, the moving average time all fell after one hour and might appear at 8 h in HRVs' largest percentage change caused by each pollutant, results of which suggested that size-fractionated PM, p-PAHs, BC, and CO exposures have delayed effects on HRVs. In conclusion, the results of the study showed that the increase in personal pollutant exposure would affect cardiac autonomic control function of healthy older residents in metropolitan areas, and the susceptibility of cardiovascular effects was higher than that of healthy young people. Since the small sample size would limit the generalizability of this study, more studies with larger scale are warranted to better understand the HRV effects of simultaneous PM and other pollution exposures for subpopulation groups.


Assuntos
Carbono/toxicidade , Frequência Cardíaca/efeitos dos fármacos , Nanopartículas/toxicidade , Material Particulado/toxicidade , Adolescente , Idoso , Idoso de 80 Anos ou mais , Poluentes Atmosféricos/análise , Poluição do Ar/análise , Carbono/química , Monóxido de Carbono/análise , Poluentes Ambientais/análise , Feminino , Frequência Cardíaca/fisiologia , Humanos , Masculino , Tamanho da Partícula , Hidrocarbonetos Policíclicos Aromáticos/análise , Taiwan
4.
Anal Chim Acta ; 1091: 76-87, 2019 Dec 24.
Artigo em Inglês | MEDLINE | ID: mdl-31679577

RESUMO

To understand the effect of Cl doping in carbon dots, nitrogen-doped carbon dots (N-Cdots) and nitrogen and chlorine dual-doped carbon dots (Cl,N-Cdots) were fabricated by high-temperature carbonization and low-temperature concentrated acid (HCl) acidification of dried shaddock peel, respectively. The quantum yield of Cl,N-Cdots is about four times of that of N-Cdots and the size of Cl,N-Cdots is smaller than that of N-Cdots. Furthermore, since trinitrophenol (PA) and ClO- could effectively quench the fluorescence of Cl,N-Cdots, the fluorescence sensors for determining PA and ClO- was constructed, respectively. The linear range of PA and ClO- are 0.9-90 µM and 3.24-216 µM with the limit of detection of 37.1 nM and 2.88 µM, respectively. The proposed sensor was used to detect PA in Taiyuan tap water, Wutai tap water, Wutai rain water and Wutai river water samples with encouraging results. The as-constructed sensor was also used to detect ClO- in Taiyuan tap water and commercial disinfectants. Last but not least, Cl,N-Cdots was employed as an agent for A549 and HeLa cell-imaging, possessing optimal imaging effect and ultra-low cytotoxicity. Our results suggested that Cl,N-Cdots has promising applications in sensing, water monitoring, commodity supervision and cell-imaging.


Assuntos
Ácido Hipocloroso/análise , Nitrofenóis/análise , Picratos/análise , Pontos Quânticos/química , Poluentes Químicos da Água/análise , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Cloro/química , Cloro/toxicidade , Citrus/química , Desinfetantes/análise , Água Potável/análise , Humanos , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Nitrogênio/química , Nitrogênio/toxicidade , Pontos Quânticos/toxicidade , Rios/química , Espectrometria de Fluorescência/métodos
5.
Mikrochim Acta ; 186(11): 708, 2019 10 23.
Artigo em Inglês | MEDLINE | ID: mdl-31641864

RESUMO

Red emissive B,N co-doped carbon dots (BN-CDs) were hydrothermally synthesized from cresyl violet and boric acid. The BN-CDs exhibited excellent photostability, low cytotoxicity, excitation/emission maxima at 520/616 nm, and a relatively high quantum yield of 18%. The BN-CDs can binded to mercury(II), and this results in quenching of the red-colored fluorescence. However, on subsequent addition of the biothiol (such as cysteine, homocysteine or glutathione), fluorescence recovers. Therefore, the BN-CDs can be used as a multifunctional probe based on "on-off-on" fluorescence response for the detection of Hg(II) and biothiols. The following detection limits were accomplished: (a) Hg(II): 2.8 µM; (b) glutathione: 1.7 µM; (c) cysteine: 2.3 µM; (d) homocysteine: 3.0 µM. The BN-CDs also have been successfully applied for the imaging of Hg(II) and biothiols in HepG2 cells with excellent bio-compatibility. Graphical abstract Red emissive B,N co-doped carbon dots (BN-CDs) were synthesized through hydrothermal treatment of cresyl violet and boric acid. The BN-CDs can be used as a multifunctional probe based on "on-off-on" fluorescence response for detecting mercury(II) and biothiols in aqueous solution and living cells.


Assuntos
Cisteína/análise , Corantes Fluorescentes/química , Glutationa/análise , Homocisteína/análise , Mercúrio/análise , Pontos Quânticos/química , Boro/química , Boro/toxicidade , Carbono/química , Carbono/toxicidade , Cor , Água Potável/análise , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Células Hep G2 , Humanos , Lagos/análise , Limite de Detecção , Microscopia Confocal , Microscopia de Fluorescência , Nitrogênio/química , Nitrogênio/toxicidade , Pontos Quânticos/toxicidade , Espectrometria de Fluorescência , Poluentes Químicos da Água/análise
6.
Anal Chim Acta ; 1090: 133-142, 2019 Dec 20.
Artigo em Inglês | MEDLINE | ID: mdl-31655638

RESUMO

A fluorescent probe for the determination of nitrite (NO2-) was fabricated by using green fluorescent nitrogen doped carbon dots (NCDs). The NCDs were synthesized via a one-pot hydrothermal carbonization of citric acid in the presence of p-phenylenediamine as the nitrogen source. The N content of the NCDs was high to 17.09% and consisted of a variety of functional groups on the NCDs surface, including sp2-hybridized CN, porphyrin C-N-C and amino N in N-(C) 3 or H-N-(C) 2 et al. N atoms were also doped within the framework of the NCDs. The almost monodisperse NCDs (average particle diameter = 3.67 nm) exhibited green photoluminescence (PL) with excitation/emission maxima of 360/505 nm. The PL of the NCDs was dependent on both excitation wavelength and solution pH. The NCDs showed a strong PL quenching response to NO2- under acidic conditions (pH = 2.5). The PL intensity of the NCDs was inversely proportional to the concentration of NO2- between 0.02 and 40 µM (R2 = 0.992), with a detection limit of 21.2 nM. The practical use of the nanoprobe for NO2- determination in food samples was also demonstrated, successfully. NCD-nitroso compounds formed because of reaction between the abundant amide groups on the surface of NCDs with the NO2-, which caused an inner filter effect and static PL quenching. Importantly, the NCDs had low cellular toxicity and were successfully used as a multicolor cellular imaging agent for Hepg2 cells.


Assuntos
Carbono/química , Corantes Fluorescentes/química , Nitritos/análise , Nitrogênio/química , Pontos Quânticos/química , Brassica/química , Carbono/toxicidade , Ácido Cítrico/química , Corantes Fluorescentes/toxicidade , Contaminação de Alimentos/análise , Células Hep G2 , Temperatura Alta , Humanos , Limite de Detecção , Microscopia de Fluorescência/métodos , Nitrogênio/toxicidade , Fenilenodiaminas/química , Pontos Quânticos/toxicidade , Carne Vermelha/análise , Espectrometria de Fluorescência/métodos , Verduras/química
7.
Analyst ; 144(22): 6729-6735, 2019 Nov 04.
Artigo em Inglês | MEDLINE | ID: mdl-31612877

RESUMO

The conjugation of ligands to nanoparticles as drug delivery systems that target specific cells is a promising approach for the delivery of therapeutic agents to tumor cells. Herein, we prepared green-emission fluorescent carbon nanodots (CNDs) by a facile hydrothermal method with d-(+)-glucosamine hydrochloride and l-aspartic acid as the precursors, then covalently conjugated with folate (FA), polyethyleneimine (PEI) and hyaluronic acid (HA) to develop dual ligand-decorated nanocarriers (FA-PEI-HA-CNDs) for the targeted imaging of cancer cells. FA-PEI-HA-CNDs integrated the excellent fluorescence property of CNDs, and can be used for the real-time and noninvasive location tracking of cancer cells. The cellular uptake study demonstrated that FA-PEI-HA-CNDs markedly improved the internalization efficiency in A-549 cells via folate/CD44 receptor-mediated endocytosis in comparison with that of the A549 cells pretreated with excess FA, HA, and FA and HA. Therefore, these dual folate/CD44 receptor-targeted CNDs (FA-PEI-HA-CNDs) show promising potential for cancer detection, drug delivery, and individualized treatment as performance platforms.


Assuntos
Corantes Fluorescentes/química , Pontos Quânticos/química , Células A549 , Carbono/química , Carbono/toxicidade , Endocitose/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Receptores de Folato com Âncoras de GPI/metabolismo , Ácido Fólico/análogos & derivados , Ácido Fólico/síntese química , Ácido Fólico/toxicidade , Humanos , Receptores de Hialuronatos/metabolismo , Ácido Hialurônico/análogos & derivados , Ácido Hialurônico/síntese química , Ácido Hialurônico/toxicidade , Ligantes , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Polietilenoimina/análogos & derivados , Polietilenoimina/síntese química , Polietilenoimina/toxicidade , Pontos Quânticos/toxicidade
8.
Anal Chim Acta ; 1089: 131-143, 2019 Dec 16.
Artigo em Inglês | MEDLINE | ID: mdl-31627810

RESUMO

In this work, the as-prepared V2O5 nanobelts can sensitively quench the fluorescence of nitrogen-doped carbon dots (N-CDs) based on the inner filter effect (IFE). In the presence of ascorbic acid (AA), the fluorescence of N-CDs can recover through the redox reaction between V2O5 nanobelts and AA. Meanwhile, in the presence of both alkaline phosphatase (ALP) and ascorbyl-2-phosphate (AAP), the fluorescence of N-CDs can also restore since AAP can be hydrolyzed into AA by ALP. Under optimum conditions, the linear range for AA is from 0.01 to 2.5 µM with a detection limit of 3 nM and that for ALP is from 0.1 to 30 U/L with a detection limit of 0.04 U/L (S/N = 3). Particularly, the proposed probe could be successfully used to detect AA and ALP in human serum samples. Furthermore, N-CDs can be applied in fluorescence imaging of Human breast cancer cells with satisfactory results.


Assuntos
Fosfatase Alcalina/sangue , Ácido Ascórbico/sangue , Corantes Fluorescentes/química , Pontos Quânticos/química , Compostos de Vanádio/química , Técnicas Biossensoriais/métodos , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Fluorescência , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Limite de Detecção , Microscopia de Fluorescência/métodos , Nitrogênio/química , Nitrogênio/toxicidade , Pontos Quânticos/toxicidade , Espectrometria de Fluorescência/métodos , Compostos de Vanádio/toxicidade
9.
Thorax ; 74(11): 1063-1069, 2019 11.
Artigo em Inglês | MEDLINE | ID: mdl-31391318

RESUMO

BACKGROUND: Ambient air pollution accelerates lung function decline among adults, however, there are limited data about its role in the development and progression of early stages of interstitial lung disease. AIMS: To evaluate associations of long-term exposure to traffic and ambient pollutants with odds of interstitial lung abnormalities (ILA) and progression of ILA on repeated imaging. METHODS: We ascertained ILA on chest CT obtained from 2618 Framingham participants from 2008 to 2011. Among 1846 participants who also completed a cardiac CT from 2002 to 2005, we determined interval ILA progression. We assigned distance from home address to major roadway, and the 5-year average of fine particulate matter (PM2.5), elemental carbon (EC, a traffic-related PM2.5 constituent) and ozone using spatio-temporal prediction models. Logistic regression models were adjusted for age, sex, body mass index, smoking status, packyears of smoking, household tobacco exposure, neighbourhood household value, primary occupation, cohort and date. RESULTS: Among 2618 participants with a chest CT, 176 (6.7%) had ILA, 1361 (52.0%) had no ILA, and the remainder were indeterminate. Among 1846 with a preceding cardiac CT, 118 (6.4%) had ILA with interval progression. In adjusted logistic regression models, an IQR difference in 5-year EC exposure of 0.14 µg/m3 was associated with a 1.27 (95% CI 1.04 to 1.55) times greater odds of ILA, and a 1.33 (95% CI 1.00 to 1.76) times greater odds of ILA progression. PM2.5 and O3 were not associated with ILA or ILA progression. CONCLUSIONS: Exposure to EC may increase risk of progressive ILA, however, associations with other measures of ambient pollution were inconclusive.


Assuntos
Poluição do Ar/efeitos adversos , Progressão da Doença , Exposição Ambiental/efeitos adversos , Doenças Pulmonares Intersticiais/etiologia , Poluição Relacionada com o Tráfego/efeitos adversos , Idoso , Poluição do Ar/análise , Carbono/análise , Carbono/toxicidade , Exposição Ambiental/análise , Feminino , Inquéritos Epidemiológicos , Humanos , Estudos Longitudinais , Doenças Pulmonares Intersticiais/diagnóstico por imagem , Masculino , Pessoa de Meia-Idade , Ozônio/análise , Ozônio/toxicidade , Material Particulado/análise , Material Particulado/toxicidade , Características de Residência , Fatores de Risco , Fatores de Tempo , Tomografia Computadorizada por Raios X , Poluição Relacionada com o Tráfego/análise
10.
Artigo em Japonês | MEDLINE | ID: mdl-31434811

RESUMO

Recently, the main air pollutant has been fine particulate matter (PM2.5), which is taken up by the whole body with severe adverse health effects. The main chemical components of PM2.5 are salts of sulfate (and nitrate) and carbons. However, it remains unknown which components are toxic. Here, the author reviewed the literatures to determine which components are toxic and the main mechanisms underlying their toxicity. Many epidemiological studies have shown that sulfate concentration is strongly related to mortality. However, there is no experimental evidence showing that sulfate at environmental concentrations of PM2.5 causes cardiovascular disease or other disease. On the other hand, carbon components such as elementary carbon (EC) produces high concentrations of reactive oxygen species (ROS) via its phagocytosis by macrophages, and organic carbon (OC) also produces high concentrations of ROS during its metabolic processes, and the ROS cause acute and chronic inflammation. They cause many diseases including cardiovascular disease, asthma and cancer. Furthermore, there are many lines of evidence showing that epigenetic changes such as DNA methylation or microRNA expression induced by particulate matters also induce the development of many diseases such as those mentioned above. It has been reported that carbon components are incorporated into the brain and produce ROS, and that the ROS cause damage to brain cells and Alzheimer's disease and cognitive disorders in the elderly.From these lines of evidence, the author would like to emphasize that the main toxicity of PM2.5 is due to carbon components, and it is important to take countermeasures to decrease the concentration of carbon components in ambient air.


Assuntos
Poluentes Atmosféricos/toxicidade , Carbono/toxicidade , Material Particulado/toxicidade , Sulfatos/toxicidade , Doença de Alzheimer/etiologia , Animais , Asma/etiologia , Doenças Cardiovasculares/etiologia , Epigênese Genética , Cobaias , Humanos , Camundongos , Neoplasias/etiologia , Estresse Oxidativo , Espécies Reativas de Oxigênio/metabolismo
11.
J Colloid Interface Sci ; 554: 722-730, 2019 Oct 15.
Artigo em Inglês | MEDLINE | ID: mdl-31362264

RESUMO

The preparation of hydrophilic carbon dots (HCDs) with imidazolium dicyanamide ionic liquids (ILs) as precursor revealed a unique structure-activity relationship for the IL-HCDs. Their hydrophilicity, fluorescence nature and cytotoxicity are closely correlated to the alkyl side chain length of the imidazolium cationic moiety. (1) The hydrophilicity of the precursor ILs decreases with the alkyl chain length of their imidazolium cations (from ethyl, butyl, hexyl, octyl to decyl). On the contrary, that of the IL-HCDs increases with the alkyl chain length due to the emergence of COC, NH2 moiety. (2) The passivation effect of alkyl chain plays a dominative role in the enhancement of quantum yield (QY, from 4.6% to 48.0%) of IL-HCDs. The doping of nitrogen-containing moieties contributes marginally. (3) The increase of alkyl chain length leads to the weakening of IL-HCDs/bovine serum albumin (BSA) affinity with a decrease on the quenching constants from 12.59 × 104 to 1.779 × 104 L mol-1. (4) The cytotoxicity of IL-HCDs increases with the length of alkyl chain in the imidazolium cation, though the hydrophilicity of IL-HCDs is increased. In addition, the cytotoxicity of IL-HCDs/BSA is lower than that of IL-HCDs. The protective effect of BSA in the IL-HCDs/BSA 'protein corona' could be utilized to improve the biocompatibility of IL-HCDs.


Assuntos
Carbono/química , Imidazóis/química , Líquidos Iônicos/química , Nanopartículas/química , Animais , Materiais Biocompatíveis/química , Materiais Biocompatíveis/metabolismo , Materiais Biocompatíveis/toxicidade , Carbono/metabolismo , Carbono/toxicidade , Bovinos , Sobrevivência Celular , Humanos , Interações Hidrofóbicas e Hidrofílicas , Imidazóis/metabolismo , Imidazóis/toxicidade , Líquidos Iônicos/metabolismo , Líquidos Iônicos/toxicidade , Células MCF-7 , Nanopartículas/metabolismo , Nanopartículas/toxicidade , Nanopartículas/ultraestrutura , Soroalbumina Bovina/metabolismo , Relação Estrutura-Atividade
12.
Mutat Res ; 842: 22-34, 2019 06.
Artigo em Inglês | MEDLINE | ID: mdl-31255223

RESUMO

Even though the outdoor air pollution and its major component Particulate Matter (PM) are recently classified as human carcinogen, attempts to elucidate the underlying mechanisms of PM toxicity are still crucial and continuing with in vitro approaches in various environmental circumstances. Present study investigated the genotoxicity (Comet assay) and the cytotoxicity (lactate dehydrogenase (LDH) leakage and the water-soluble tetrazolium (WST-1) assays) of 30 daily PM2.5 samples collected in the Kütahya province, to address their daily variability in effects with season (i.e. winter versus summer) and location (i.e. rural versus urban) using A549 human lung cancer epithelial cell line, as well as in relation to their chemical composition, specifically trace elements, organic carbon (OC) and elemental carbon (EC). The genotoxicity, measured by the percentage tail intensity (TI), of the daily PM2.5 samples at the traffic dense urban station was higher than that of the rural site for 80% of the parallel days. The genotoxicity was significant in the winter at the urban and in the summer at the rural site. Cytotoxicity was the highest for the winter urban samples. The PM2.5 mass, OC, and EC concentrations were not correlated to DNA damage, while there were correlations with Mn, Fe, Cu and Ba at the rural PM2.5 samples, and Mn, Co and Ni at the urban samples, respectively. The present study is confirming that the complex composition of PM2.5 originating from spatial and temporal changes can cause differences in the health effects.


Assuntos
Poluentes Atmosféricos/toxicidade , Citotoxinas/toxicidade , Material Particulado/toxicidade , Células A549 , Poluição do Ar/efeitos adversos , Carbono/toxicidade , Linhagem Celular Tumoral , Ensaio Cometa/métodos , Dano ao DNA/efeitos dos fármacos , Monitoramento Ambiental/métodos , Humanos , Tamanho da Partícula , Estações do Ano
13.
Talanta ; 204: 74-81, 2019 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-31357360

RESUMO

The abnormal expression level of alkaline phosphatase (ALP) will lead to serious diseases. Therefore, a sensitive and rapid assay for ALP activity monitoring is of vital importance. In this work, a fluorescence turn-off approach for the detection of ALP is designed on the basis of nitrogen doped carbon dots (N-CDs), which were synthesized by one-step hydrothermal method and applied as signal readout. p-Nitrophenylphosphate (PNPP) can be hydrolyzed into p-nitrophenol (PNP) by ALP and their absorption peaks are different under alkaline conditions, so it was chosen as the ALP substrate. The absorption spectrum of PNP has good overlap with the excitation and emission spectra of N-CDs, thus the fluorescence of N-CDs can be effectively quenched by PNP via the inner filter effect (IFE). Consequently, quantitative detection of ALP is realized because the relative fluorescence intensity is linearly with the ALP activity in a wide range from 0.05 to 40 U L-1. The detection limit is 0.02 U L-1 (S/N = 3), which is much lower than the normal level of serum ALP in adults (about 40-190 U L-1). Moreover, the assay was successfully applied to evaluate ALP inhibitor efficiency and screen ALP inhibitors in drug discovery. It is also demonstrated that N-CDs possesses low cytotoxicity, excellent biocompatibility and photostability, and can be successfully applied in vivo fluorescence imaging, showing great potential in clinical applications.


Assuntos
Fosfatase Alcalina/sangue , Pontos Quânticos/química , Carbono/química , Carbono/toxicidade , Fluorescência , Células HeLa , Humanos , Limite de Detecção , Nitrogênio/química , Nitrogênio/toxicidade , Pontos Quânticos/toxicidade , Espectrometria de Fluorescência/métodos
14.
Environ Toxicol Chem ; 38(10): 2314-2325, 2019 10.
Artigo em Inglês | MEDLINE | ID: mdl-31343769

RESUMO

Manufactured nanomaterial production is outpacing the ability to investigate environmental hazard using current regulatory paradigms, causing a backlog of materials requiring testing. To ameliorate this issue, regulatory bodies have proposed integrating safety into the production of novel nanomaterials, allowing for hazards to be identified early in development rather than aftermarket release. In addition, there is a growing interest in short-term ecotoxicity testing to rapidly identify environmental hazards. In this sense, the present study investigated 3 carbon nanofibers (CNFs), created with different production methods, using short-term in vitro and in vivo exposures on fish cell lines, mussel hemocytes, crustacea, and algae. The present study investigated if differences in ecotoxicity hazard between the CNFs could be identified and, if so, which product could be considered less hazardous. A major challenge in assessing the potential hazards posed by manufactured nanomaterials is standardizing the preparation for testing. Standardized operating protocols have been proposed using protein to facilitate the preparation of stable stock suspension, which is not environmentally representative. As such, the study also assessed the potential impacts these standardized protocols (with or without the use of protein) could have on the interpretation of environmental hazard. The results demonstrated that there were clear differences between the 3 CNFs and that the dispersion protocol influenced the interpretation of hazard, demonstrating a need for caution when interpreting ecotoxicity in a regulatory context. Environ Toxicol Chem 2019;38:2314-2325. © 2019 SETAC.


Assuntos
Organismos Aquáticos/efeitos dos fármacos , Carbono/toxicidade , Ecotoxicologia , Nanofibras/toxicidade , Animais , Linhagem Celular , Daphnia/efeitos dos fármacos , Peixes/crescimento & desenvolvimento , Hemócitos/efeitos dos fármacos , Mytilus/efeitos dos fármacos , Nanofibras/ultraestrutura , Especificidade da Espécie
15.
Int J Pharm ; 569: 118521, 2019 Oct 05.
Artigo em Inglês | MEDLINE | ID: mdl-31323371

RESUMO

Carbon dots (CDs) are emerging nanomaterial in medicine and pharmacy. To explore the impact of physicochemical characteristics on their safety, we synthesized a library of 35 CDs exhibiting different size, charge, chemical composition and surface coating, using various starting materials (carbon source and passivation reagent) and carbonization procedures. The 35 CDs triggered different levels of viability loss when incubated with human macrophages at 3-200 µg/mL for 24 h. The smaller NPs (10-20 nm) were more toxic that larger ones (40-100 nm), whereas NPs that aggregated in culture medium were more toxic than dispersed ones. A positive correlation was found between CD charge or nitrogen content and toxicity. Furthermore, a greater toxicity was observed for CDs prepared from high molecular weight polyamines, suggesting a role of the CD global density of positive charges, rather than the charge at the CD surface, in the CD toxicity. At last, PEG decoration decreased the toxicity of cationic NPs. In conclusion, the size, aggregation in culture medium, charge, nitrogen content, nature of the passivation agent and synthesis procedure were found to influence CD toxicity, making it difficult to predict CD safety from a single characteristic.


Assuntos
Carbono/toxicidade , Nanopartículas/toxicidade , Carbono/química , Sobrevivência Celular/efeitos dos fármacos , Humanos , Nanopartículas/química , Tamanho da Partícula , Bibliotecas de Moléculas Pequenas , Células THP-1
16.
Mikrochim Acta ; 186(7): 469, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31240482

RESUMO

An ultrasensitive and highly reliable ratiometric assay is described for the determination of microRNA-155. It works at the attomolar concentration level and has high selectivity which warrants its potential application in cancer biomarker tracking. The excellent performance of this method results from (a) the use of a hybrid conjugate prepared from Rhodamine B (RhB), carbon dots (CDs) and probe-microRNA, and (b) from the measurement of fluorescence resonance energy transfer (FRET) that is observed in the AuNP/target-microRNA system as a result of RNA hybridization. The dye RhB (emission peak at 580 nm) serves as an internal reference. The sensitivity of this assay is increased by about 30% because of the broad emissions of CDs (489 nm and 665 nm) through a sequential FRET phenomenon. RhB-CDs were covalently bio-conjugated to probe microRNA. In the presence of AuNPs, the fluorescence of the CDs is quenched, while in the presence of microRNA-155, the ratio of fluorescences at 489 and 665 nm (I489/I665) is enhanced again. A linear relationship exists between the ratio of fluorescence and the concentration of microRNA-155 in the range from 1 aM to 0.1 µM, and the detection limit is 0.3 aM. The assay was applied to quantitative studies of target microRNA-155 in multiple pathways associated with cancer progression in biological fluids include human serum samples and cancer cells. The nanoprobe also deliver clear signal to microRNA target in fixed and lived MDA-MB-231 cells. Graphical abstract A ratiometric FRET sensing method used for microRNA-155 detection at aM concentration level using CDs and AuNPs as donor-acceptor respectively and Rhodamine B as amplification reagent. The application of assay for imaging of microRNA-155 in fixed and live MDA-MB-231 cells is demonstrated.


Assuntos
Transferência Ressonante de Energia de Fluorescência/métodos , Nanopartículas Metálicas/química , MicroRNAs/análise , Pontos Quânticos/química , Sondas RNA/química , Rodaminas/química , Técnicas Biossensoriais/métodos , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Ouro/química , Humanos , Limite de Detecção , MicroRNAs/genética , Hibridização de Ácido Nucleico , Pontos Quânticos/toxicidade , Sondas RNA/genética , Rodaminas/toxicidade
17.
Mikrochim Acta ; 186(7): 468, 2019 06 25.
Artigo em Inglês | MEDLINE | ID: mdl-31240486

RESUMO

New green-emissive carbon dots (G-CDs) are described here and shown to be viable fluorescent nanoprobes for the detection of changes in cellular pH values. By using m-phenylenediamine as the carbon source, G-CDs with an absolute quantum yield of 36% were solvothermally synthesized in the presence of strong H2SO4. The G-CDs have an average size of 2.3 nm and display strong fluorescence with excitation/emission peaks at 450/510 nm. The fluorescence intensity depends on the pH value in the range from 6.0 to 10.0, affording the capability for sensitive detection of intracellular pH variation. The nanosensor with excellent photostability exhibited good fluorescence reversibility in different pH solutions, and showed excellent stability against the influence of other biological species. The nanoprobe was successfully used in confocal fluorescence microscopy to determine pH values in SMMC-7721 cells. Graphical abstract Schematic presentation of green-emissive carbon dots (G-CDs) synthesized using m-phenylenediamine and sufuric acid through a solvothermal method for real-time fluorometric monitoring of intracellular pH values. Mechanism can be ascribed to PET process from the electron lone pair in amino group to the CDs.


Assuntos
Corantes Fluorescentes/química , Pontos Quânticos/química , Carbono/química , Carbono/toxicidade , Linhagem Celular Tumoral , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/toxicidade , Humanos , Concentração de Íons de Hidrogênio , Microscopia Confocal/métodos , Microscopia de Fluorescência/métodos , Fenilenodiaminas/química , Pontos Quânticos/toxicidade
18.
Analyst ; 144(15): 4569-4574, 2019 Aug 07.
Artigo em Inglês | MEDLINE | ID: mdl-31225569

RESUMO

A high quantum yield (QY) is the key requirement for implementing carbon dots (CDs) in nearly all applications. In this work, blue emissive N-doped CDs with a QY of 83% and orange emissive N-doped CDs with a QY of 47% were successfully prepared using resorcinol and phloroglucin as carbon resources in formamide by one-step microwave synthesis, respectively. Formamide not only plays a role as the solvent but also takes part in the formation of the high QY CDs. It is demonstrated that the as-prepared blue- and orange-emitting N-doped CDs with a high QY can be uniformly dispersed into glue and be fabricated as CD/glue fluorescent composites for fluorescent films and fingerprint imaging. Furthermore, these CDs also show excellent cellular imaging capability.


Assuntos
Carbono/química , Pontos Quânticos/química , Adesivos/química , Carbono/efeitos da radiação , Carbono/toxicidade , Cor , Dermatoglifia , Fluorescência , Humanos , Células MCF-7 , Membranas Artificiais , Microscopia de Fluorescência , Micro-Ondas , Floroglucinol/química , Pontos Quânticos/efeitos da radiação , Pontos Quânticos/toxicidade , Resorcinóis/química , Solubilidade
19.
Molecules ; 24(9)2019 May 08.
Artigo em Inglês | MEDLINE | ID: mdl-31072045

RESUMO

A novel sensing system has been designed for the detection of cupric ions. It is based on the quenched fluorescence signal of carbon dots (CDs), which were carbonized from poly(vinylpyrrolidone) (PVP) and L-Cysteine (CYS). Cupric ions interact with the nitrogen and sulfur atoms on surface of the CDs to form an absorbed complex; this results in strong quenching of the fluorescence of the CDs via a fast metal-to-ligand binding affinity. The synthesized water-soluble CDs also exhibited a quantum yield of 7.6%, with favorable photoluminescent properties and good photostability. The fluorescence intensity of the CDs was very stable in high ionic strength (up to 1.0 M NaCl) and over a wide range of pH levels (2.0-12.0). This facile method can therefore develop a sensor that offers reliable, fast, and selective detection of cupric ions with a detection limit down to 0.15 µM and a linear range from 0.5 to 7.0 µM (R2 = 0.980). The CDs were used for cell imaging, observed that they were low toxicity to Tramp C1 cells and exhibited blue and green and red fluorescence under a fluorescence microscope. In summary, the CDs exhibited excellent fluorescence properties, and could be applied to the selective and sensitive detection of cupric ion and multicolor cell imaging.


Assuntos
Carbono/química , Cobre/análise , Imageamento Tridimensional/métodos , Sondas Moleculares/síntese química , Pontos Quânticos/química , Animais , Carbono/toxicidade , Morte Celular/efeitos dos fármacos , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Fluorescência , Íons , Camundongos Transgênicos , Sondas Moleculares/química , Espectroscopia Fotoeletrônica , Pontos Quânticos/toxicidade , Espectrometria de Fluorescência , Espectrofotometria Ultravioleta , Espectroscopia de Infravermelho com Transformada de Fourier , Poluentes Químicos da Água/análise
20.
Part Fibre Toxicol ; 16(1): 18, 2019 04 11.
Artigo em Inglês | MEDLINE | ID: mdl-30975174

RESUMO

BACKGROUND: Carbon nanomaterials are a growing family of materials featuring unique physicochemical properties, and their widespread application is accompanied by increasing human exposure. MAIN BODY: Considerable efforts have been made to characterize the potential toxicity of carbon nanomaterials in vitro and in vivo. Many studies have reported various toxicology profiles of carbon nanomaterials. The different results of the cytotoxicity of the carbon-based materials might be related to the differences in the physicochemical properties or structures of carbon nanomaterials, types of target cells and methods of particle dispersion, etc. The reported cytotoxicity effects mainly included reactive oxygen species generation, DNA damage, lysosomal damage, mitochondrial dysfunction and eventual cell death via apoptosis or necrosis. Despite the cellular toxicity, the immunological effects of the carbon-based nanomaterials, such as the pulmonary macrophage activation and inflammation induced by carbon nanomaterials, have been thoroughly studied. The roles of carbon nanomaterials in activating different immune cells or inducing immunosuppression have also been addressed. CONCLUSION: Here, we provide a review of the latest research findings on the toxicological profiles of carbon-based nanomaterials, highlighting both the cellular toxicities and immunological effects of carbon nanomaterials. This review provides information on the overall status, trends, and research needs for toxicological studies of carbon nanomaterials.


Assuntos
Carbono/toxicidade , Citocinas/metabolismo , Pulmão/efeitos dos fármacos , Nanoestruturas/toxicidade , Animais , Apoptose/efeitos dos fármacos , Apoptose/imunologia , Carbono/química , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Sobrevivência Celular/imunologia , Humanos , Pulmão/imunologia , Pulmão/patologia , Linfócitos/efeitos dos fármacos , Linfócitos/imunologia , Linfócitos/patologia , Macrófagos/efeitos dos fármacos , Macrófagos/imunologia , Macrófagos/patologia , Nanoestruturas/química , Tamanho da Partícula , Propriedades de Superfície
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