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1.
J Nanosci Nanotechnol ; 20(2): 701-708, 2020 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-31383065

RESUMO

In the present study we developed novel luminescent magnetic nanocomposites termed Fe3O4@polyaniline/carbon dots. First, Fe3O4 magnetic nanoparticles were prepared by the coprecipitation method. The nanoparticles were then coated with polyaniline using the in situ growth method to form Fe3O4@polyaniline nanohybrids, which were endowed with amino functional groups on the surface and avoided the aggregation of Fe3O4 nanoparticles. The X-ray diffraction pattern demonstrated that the crystalline phase of the Fe3O4 nanoparticles was an inverse spinel structure and was not changed in the Fe3O4@polyaniline nanohybrids. The saturation magnetization and the coercive force of the as-prepared Fe3O4@polyaniline nanohybrids measured by a vibrating sample magnetizer were 63.7 emu·g-1 and zero respectively, which indicated that the Fe3O4@polyaniline nanohybrids exhibited excellent superparamagnetism. The Fe3O4@polyaniline nanohybrids were conjugated with carbon dots, prepared from orange juice, via the amide bond between the amino groups on the surface of the Fe3O4@polyaniline nanohybrids and the carboxyl groups on the surface of carbon dots. The obtained luminescent magnetic nanocomposites Fe3O4@polyaniline/carbon dots showed good photoluminescent properties, which hinted that the nanocomposites have potential in drug tracing and magnetic targeted drug delivery. Finally, the anticancer drug methotrexate was loaded into the Fe3O4@polyaniline/carbon dots nanocomposites, forming a novel magnetic targeted drug delivery system. The results confirmed that the novel drug delivery system exhibited excellent drug-loading capability for methotrexate of ca. 70%, and emits strong fluorescence at the wavelength of 360 nm. An in vitro release experiment of the drug delivery system indicated that the cumulative release percentage of methotrexate was 17.2% in the phosphate-buffered saline (pH = 7.4) within 36 h.

3.
Enzyme Microb Technol ; 127: 50-57, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31088616

RESUMO

Macrophages eliminate and destroy invading bacteria and contaminants by engulfing them or secreting cytokines that trigger downstream immune responses. Consequently, impairment of the phagocytic functions of macrophages and/or suppressing their cytokine secretion are dangerous to organisms that rely on immune protection. Accordingly, exposure to environmental nanoparticles (NPs) that display immunomodulatory properties are serious. In this work, two types of NPs, i.e., mild-toxicity CuInS2 NPs and high-toxicity CdTe NPs, were used to evaluate the effects of NP exposure for macrophages. Following incubation for 24 h, THP-1-derived macrophage viability was assessed using an MTT method after exposing the THP-1 cells to different concentrations of CuInS2 or CdTe NPs. Phagocytosis assays demonstrated that both CuInS2 and CdTe NPs impair phagocytic activity toward Staphylococcus aureus (S. aureus). After pretreatment with CuInS2 and CdTe NPs at 4 µmol/L, THP-1 macrophages exhibited decreases in phagocytic ratio from ca. 32.9% to ca. 18.5% and 18.7%, respectively. Since the zeta potentials of intact and weathered CuInS2 NPs were distributed over a wide range from positive to negative, large quantities of intact and weathered CuInS2 NPs bore sufficient positive charge on their surfaces to induce membrane depolarization, thus theoretically providing electrostatic forces between S. aureus and THP-1, which could induce downstream intracellular events that increase phagocytosis. However, real time polymerase chain reaction arrays revealed that transcription of the pro-inflammatory factors IL-1ß, IL-6, and TNF-α decreased while that of the anti-inflammatory factor IL-10 increased after treatment with CuInS2 NPs. Furthermore, transcription of TNF-α decreased while IL-10 increased after treatment with CdTe NPs. Thus, both kinds of NPs inhibited phagocytosis of S. aureus by THP-1 to some extent, confirming that immunosuppression can occur when macrophages are exposed to environmental NPs.


Assuntos
Citocinas/metabolismo , Fatores Imunológicos/metabolismo , Macrófagos/efeitos dos fármacos , Nanopartículas/metabolismo , Fagocitose/efeitos dos fármacos , Sobrevivência Celular/efeitos dos fármacos , Humanos , Fatores Imunológicos/química , Macrófagos/metabolismo , Nanopartículas/química , Staphylococcus aureus/imunologia , Células THP-1
4.
J Hazard Mater ; 374: 420-427, 2019 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-31035092

RESUMO

Heavy metal cadmium (Cd) has drawn tremendous comcern due to its rigorous environmental and health hazards. Herein, we have presented an efficient and economical strategy for the removal and recycling of hazardous Cd ions using microalgae cells as the bioreactors. Remarkably, the green bio-platform for the bioproduction of CdSe nanoparticles (NPs) was developed depending on their orderly regulated and sustainable cellular environment. The biofabricated CdSe NPs manifested favorable photoluminescence properties, and presented well monodispersed spherical morphology and certain crystallinity structure with mean size of smaller than 7 nm. Especially, the fluorescence "turn off" sensing system based on the CdSe NPs was established to detect Hg2+. The nanosensor enables the quantitative analyses of Hg2+ with a linear range of 0-2.0 µM and a detection limit of 0.021 µM. Furthermore, it was preliminarily speculated that the reducing biomolecules in the algae cells could be involved in the formation of CdSe NPs. This work not only provides new insights into the removal and recycling of hazardous Cd ions, but also brings a promising route for biosynthesis of CdSe NPs.

5.
Ecotoxicol Environ Saf ; 172: 444-450, 2019 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-30735977

RESUMO

Due to the extensive use in consumer products, the bisphenols (BPs) pollution in the environments has aggravated and people are frequently exposed to BPs. In this research, four BPs, i.e., bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS) and bisphenol AF (BPAF), were determined in urine samples collected from Gaochun District preschool-age children and the concentrations, distribution profiles, potential sources and cumulative risk assessment of the target compounds were studied. Total concentrations of 4 BPs ranged from 2 to 3113.1 ng/L, with the average concentration of 648.6 ng/L. BPA was the predominant congener (accounting for 94%), followed by BPS. Correlation analysis indicated a negative relationship between BPA and BPAF (R = -0.273, p < 0.05). The estimated daily intakes suggested that young females were more sensitive to BPs. Moreover, the cumulative risk for hazard quotient (HQ) of BPA has been evaluated and the results showed that no high risk had occurred. It provided basic information on the occurrence and human exposure to urinary BPs of preschool aged children from Gaochun District.


Assuntos
Compostos Benzidrílicos/urina , Fenóis/urina , Sulfonas/urina , Criança , Pré-Escolar , China , Exposição Ambiental , Feminino , Humanos , Masculino , Medição de Risco , Tamanho da Amostra
6.
Ecotoxicol Environ Saf ; 171: 728-736, 2019 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-30658309

RESUMO

Quantum dots (QDs), as a kind of novel nanomaterial, have the extensive applications in various fields, inevitably leading to increasing risks for the ecological environment. The mobilization of cadmium including metal smelting and subsequent machining for multifarious applications has caused the release of cadmium element into the environment. In this study, we evaluated the potential toxicity of a novel nanoparticle material CdSe QDs, using two green algae Chlorella pyrenoidosa and Scenedesmus obliquus. The impact of CdSe QDs and cadmium ions on algae and the sensitivity of the two algae on target compounds were also considered and compared. Our results showed the algal growth rates and chlorophyll content decreased with increasing exposure concentrations and durations. Moreover, the glutathione levels were decreased while the activities of superoxide dismutase increased, exhibiting their pivotal functions in defeating toxic stress. The increment of malondialdehyde levels revealed that the stresses of CdSe QDs and cadmium ions were contributed to the occurrence of oxidative damage. Our study also indicated that the impact of CdSe QDs was stronger than that of cadmium nitrate and the algal response was also species-specific. In addition, the TEM photographs of the algal ultrastructure showed the presence of surface attachment and uptake of QDs.


Assuntos
Compostos de Cádmio/toxicidade , Chlorella/efeitos dos fármacos , Poluentes Ambientais/toxicidade , Pontos Quânticos/toxicidade , Scenedesmus/efeitos dos fármacos , Compostos de Selênio/toxicidade , Chlorella/crescimento & desenvolvimento , Chlorella/metabolismo , Clorofila/metabolismo , Relação Dose-Resposta a Droga , Malondialdeído/metabolismo , Metalurgia , Scenedesmus/crescimento & desenvolvimento , Scenedesmus/metabolismo , Superóxido Dismutase/metabolismo
7.
Ecotoxicol Environ Saf ; 170: 47-54, 2018 Dec 03.
Artigo em Inglês | MEDLINE | ID: mdl-30522006

RESUMO

Because the application of Bisphenol A (BPA) was restricted, many substitutes, such as Bisphenol F (BPF) and Bisphenol S (BPS), were developed as BPA substitutes. Therefore, environmental impacts of BPA and its substitutes on aquatic organisms should be concerned, especially their combined toxicity. In this study, the impacts of BPA, BPF, BPS and their mixture on the feeding behavior, reproduction and physiological function of daphnids were synthetically evaluated, involving the duration and mode of exposure. In short-term exposure tests, feeding rates of D. magna decreased after exposure to BPA, BPF, BPS and their mixture, while the inhibition reversed into stimulation in the recovery period. It may benefit from overcompensation of D. magna. In long-term exposure tests, the inhibition effect on the reproduction and growth of the exposed D. magna was difficult to recover, and only some experimental groups have a certain recovery. In conclusion, environmental risk of BPA, BPF, BPS and their mixture on the behavior of D. magna increased with prolonged exposure time. Moreover, relative activities of trypsin, amylase (AMS), acetylcholinesterase (AChE), carbonic anhydrase (CA), glutathione peroxidase (GPx) and super oxidase dimutase (SOD) of the exposed daphnids decreased in most treatment groups, indicating the disorder of digestive, nervous and antioxidative system of D. magna. Interestingly, inhibition of enzymes activities decreased with the increase of the exposure time, which implied the tolerance may be occurred.

8.
Chemosphere ; 218: 376-383, 2018 Nov 17.
Artigo em Inglês | MEDLINE | ID: mdl-30476769

RESUMO

The study analyzed the correlation between the antibiotic-induced feeding depression and body size reduction in rotifer, Brachionus calyciflorus, involving exposure, post-exposure and re-exposure periods. The filtration and ingestion rates of the rotifers were inhibited in these three exposure periods at any given concentration of the antibiotic sulfamethazine (SMZ). As food for rotifer, the cell size of the green algae was unchanged, which indicated that it could not drive feeding depression. Secondly, several corresponding physiological responses were considered. Reactive oxygen species (ROS) levels increased in the post-exposure and the re-exposure; acetylcholinesterase (AChE) activity was significantly decreased in the exposure and the re-exposure, whereas it was induced in the post-exposure. The activities of amylase and lipase were always inhibited in these three exposure periods. Additionally, significant decreases in lorica length, width and biovolume of rotifers occurred after the feeding depression. Statistical analysis indicated a positive correlation between the activity of the digestive enzyme and the body size. Our results demonstrated that SMZ could influence the neurotransmission, inhibit the activity of the digestive enzyme, and finally result in body size reduction. These results provided an integrated perspective on assessing the toxicity effects of antibiotic in non-lethal dosage on the feeding behavior of non-target aquatic organisms.

9.
Enzyme Microb Technol ; 119: 37-44, 2018 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-30243385

RESUMO

Bacillus amyloliquefaciens containing intracellularly biosynthesized cadmium selenide (CdSe) quantum dots (QDs) was used as a fluorescent bioprobe. Several parameters in the QD biosynthesis process were systematically optimized. The optimized protocol for producing high-quality CdSe QDs in B. amyloliquefaciens features mild synthetic conditions, good reproducibility, short reaction time and high yield. This process shows promise for the mass production of QDs by bacterial matrices. The resultant fluorescent B. amyloliquefaciens containing intracellular CdSe QDs was used as a bioprobe for the simple detection of copper (II) ions in blood plasma. The selective permeability of the bacterial cell membrane along with the protection provided by a protein envelope on the QD surface prevented interference by other components of blood plasma, resulting in the accurate determination of Cu2+. Using the copper addition method, the content of Cu2+ in human blood plasma samples was determined to be 15.6-18.5 µmol/L, consistent with atomic absorption spectroscopy results. The technique developed here shows potential for the simple determination of Cu2+ in plasma with excellent selectivity and good sensitivity.

10.
Bioconjug Chem ; 29(8): 2838-2845, 2018 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-30058797

RESUMO

Hypochlorite (OCl-), an essential part of reactive oxygen species (ROS), plays a crucial role in cellular redox balance. OCl- has been shown to be implicated in many physiological and pathological processes, including liver injury and cancer. Exploitation of fluorescent probes for the OCl- helps to reveal its function in the genesis and progression of the aforementioned diseases. Here we propose an easy-to-fabricate coumarin-based fluorescent probe incorporated with an aryl dihydrazide linker for highly specific detection and biological imaging of OCl- in living cells and tissues. The p-nitrophenyl-modified dihydrazide-linked coumarin derivative (Cou-dhz-Ph-NO2) was screened from a series of candidate molecules and served as a "turn-on" probe with a low background fluorescence interference due to the nitro-group-based quenching on the coumarin fluorescence. The Cou-dhz-Ph-NO2 probe showed high selectivity and fast response with excellent linear relationship for detection of OCl-. A specific OCl--responsive mechanism that the dihydrazide linker could be oxidatively cleaved by OCl- was deduced. The exogenous OCl- and endogenous OCl- were successfully visualized using the Cou-dhz-Ph-NO2 probe in living cells, such as MDA-MB-231 cells, RAW 264.7 cells and neutrophils, and the pathologic tissues, including the tumor tissue and the acutely injured liver tissue. This study paves the way for utilizing the aryl dihydrazide linker as OCl--responsive module, which can aid the evolution of increasingly specific probes for detection of OCl- and diagnosis of OCl--coupled diseases.

11.
Chemosphere ; 195: 784-792, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29289905

RESUMO

Persistence of antibiotics in aquatic environment may pose a risk to the non-target aquatic organisms. This study provided an integrated evaluation to analyze the toxic stress of sulfamethazine (SMZ) on zebrafish in two lifespan stages (embryo-larval and adult) and three exposure periods (exposure, post-exposure and re-exposure). Zebrafish embryos and adult zebrafish were exposed to SMZ at 0.2, 20 and 2000 µg/L, respectively. The results showed that SMZ at any given concentration inhibited the hatching of embryos at 58-96 hpf (hours post-fertilization). Our result also indicated that two major kinds of the malformation, which was induced by the antibiotic, were edema and spinal curvature. Additionally, the antibiotic stimulated the heartbeat while reduced the body length of the embryo at 72 hpf. Superoxide dismutase (SOD) activities and malondialdehyde (MDA) contents significantly increased at 120 hpf when the embryos were exposed to the lowest concentration (0.2 µg/L) of the antibiotic. On the other hand, the antibiotic induced SOD activities and MDA contents in adult zebrafish in the exposure and re-exposure periods. The MDA contents could recover while SOD activities still increased in 2 d after the exposure. Both SOD activities and MDA contents could recover in 7 d after the exposure. Levels of SOD and MDA in the re-exposure were higher than those in the first exposure. Our results suggested that SMZ had toxic effects on both embryos and adult zebrafish, and provided an integrated evaluation of the toxic effects of SMZ on zebrafish at a new perspective.


Assuntos
Antibacterianos/toxicidade , Larva/efeitos dos fármacos , Sulfametazina/toxicidade , Peixe-Zebra/embriologia , Peixe-Zebra/crescimento & desenvolvimento , Animais , Larva/genética , Larva/crescimento & desenvolvimento , Larva/metabolismo , Malondialdeído/metabolismo , Estresse Oxidativo/efeitos dos fármacos , Superóxido Dismutase/genética , Superóxido Dismutase/metabolismo , Peixe-Zebra/genética , Peixe-Zebra/metabolismo , Proteínas de Peixe-Zebra/genética , Proteínas de Peixe-Zebra/metabolismo
12.
Luminescence ; 33(2): 318-325, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29044942

RESUMO

Here, we have presented a green and facile strategy to fabricate nitrogen-doped carbon dots (N-CDs) and their applications for determination of chlortetracycline (CTC) and sulfasalazine (SSZ). The fluorescent N-CDs, prepared by one-step hydrothermal reaction of citric acid and l-arginine, manifested numerous excellent features containing strong blue fluorescence, good water-solubility, narrow size distribution, and a high fluorescence quantum yield (QY) of 38.8%. Based on the fluorescence quenching effects, the as-synthesized N-CDs as a fluorescent nanosensor exhibited superior analytical performances for quantifying CTC and SSZ. The linear range for CTC was calculated to be from 0.85 to 20.38 µg ml-1 with a low detection limit of 0.078 µg ml-1 . Meanwhile, the linear range for SSZ was estimated to be from 0.34 to 6.76 µg ml-1 with a low detection limit of 0.032 µg ml-1 . Therefore, the N-CDs hold admirable application potential for constructing a fluorescent sensor for pharmaceutical analysis.


Assuntos
Antibacterianos/análise , Carbono/química , Clortetraciclina/análise , Medições Luminescentes/métodos , Pontos Quânticos/química , Sulfassalazina/análise , Fluorescência , Medições Luminescentes/instrumentação , Nitrogênio/química
13.
Chemosphere ; 195: 542-550, 2018 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-29277034

RESUMO

Although 2,2',4,4'-tetrabrominated diphenyl ether (BDE-47), 6-hydroxy-2,2',4,4'-tetrabromodiphenyl ether (6-OH-BDE-47) and 6-methoxy-2,2',4,4'-tetrabromodiphenyl ether (6-MeO-BDE-47) clearly disrupt the endocrine system, current knowledge of their single and/or mixture toxicities on other behaviors of aquatic organisms remains limited. In the present study, Daphnia magna was used to investigate the single and mixture toxicities of BDE-47, 6-OH-BDE-47 and 6-MeO-BDE-47 as measured by inhibition of feeding during exposure and post-exposure periods. Additionally, the biochemical performance, i.e., the activities of super oxidase dismutase (SOD), glutathione peroxidase (GPx) and acetylcholinesterase (AChE) of the test organism was studied to investigate the potential mechanisms of the toxicity of the target compounds. The three target compounds produced an obvious depressive effect on feeding behavior during the exposure period, and the effect increased with increasing concentrations. D. magna was most sensitive to 6-OH-BDE-47. The toxicity of the ternary mixture showed an obvious concentration-dependent effect, whereas the binary mixture toxicity showed the characteristics of hormesis. During the post-exposure period, overcompensation occurred, indicating a short-term effect of the target compounds on D. magna. Additionally, significant changes occurred in neurological responses, indicating that these compounds might have neurobehavioral toxicity in D. magna. The decrease in oxidative stress enzymes (SOD and GPx) indicated that the antioxidant response of D. magna was destroyed.


Assuntos
Anisóis/toxicidade , Daphnia/efeitos dos fármacos , Comportamento Alimentar/efeitos dos fármacos , Éteres Difenil Halogenados/toxicidade , Bifenil Polibromatos/toxicidade , Animais , Daphnia/metabolismo , Disruptores Endócrinos/toxicidade , Glutationa Peroxidase/metabolismo , Síndromes Neurotóxicas/etiologia , Estresse Oxidativo
14.
Enzyme Microb Technol ; 107: 41-48, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28899485

RESUMO

Quantum dots (QDs) are semiconductor nanoparticles (NPs) that offer valuable functionality for cellular labeling, drug delivery, solar cells and quantum computation. In this study, we reported that CdSe QDs could be bio-synthesized in Bacillus licheniformis. After optimization, the obtained CdSe QDs exhibited a uniform particle size of 3.71±0.04nm with a maximum fluorescence emission wavelength at 550nm and the synthetical positive ratio can reach up to 87%. Spectral properties, constitution, particle sizes and crystalline phases of the CdSe QDs were systematically and integrally investigated. The CdSe QD-containing Bacillus licheniformis cells were further used as whole fluorescent bio-probes to detect copper (II) (Cu2+) in water, which demonstrated a low limit of detection (0.91µM). The assay also showed a good selectivity for Cu2+ over other ions including Al3+, Cd2+, Mg2+, K+, Na+, NH4+, Zn2+, CH3COO+, Pb2+ and I-. Our study suggests the fluorescent CdSe QDs-containing Bacillus licheniformis bio-probes as a promising approach for detection of Cu2+ in complex solution environment.


Assuntos
Bacillus licheniformis/metabolismo , Compostos de Cádmio , Cobre/análise , Pontos Quânticos/metabolismo , Pontos Quânticos/microbiologia , Compostos de Selênio , Água/análise , Corantes Fluorescentes/química , Limite de Detecção , Pontos Quânticos/ultraestrutura , Espectrometria de Fluorescência , Poluentes Químicos da Água/análise
15.
Chemosphere ; 185: 423-430, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28710991

RESUMO

The anticancer drugs are getting increasing attention as an emerging contaminant in the aquatic environments. In the present study, feeding behavior of the rotifer Brachionus calyciflorus under the impact of anticancer drug imatinib was evaluated. Traditional toxicological studies usually focus on dose-effect relationship at a given exposure time, while ignore the possible impact after the exposure. Thus, how the impact varied in the post-exposure and re-exposure was also considered in the present study. The feeding depression of the rotifers was attributed to the increased concentration of imatinib. Although the filtration and ingestion rate of the rotifers recovered to a certain extent after the exposure, the significant feeding inhibition still persisted even if the exposure was ended. In the re-exposure period, the feeding behavior was less depressed than those of the exposure period, which implied that rotifers might develop a tolerance to the same toxics. The activities of acetylcholine esterase (AchE) and the levels of reactive oxygen species (ROS) in rotifers were also detected. Imatinib inhibited the activities of AchE in the exposure and re-exposure while ROS levels increased significantly in the re-exposure period. Our present study provided an integrated assessment the potential environmental risks of imatinib at a new perspective.


Assuntos
Comportamento Alimentar/efeitos dos fármacos , Mesilato de Imatinib/farmacologia , Rotíferos/efeitos dos fármacos , Poluentes Químicos da Água/farmacologia , Acetilcolinesterase/metabolismo , Animais , Antineoplásicos/farmacologia , Espécies Reativas de Oxigênio/metabolismo
16.
Chemosphere ; 184: 318-328, 2017 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-28601665

RESUMO

Compared to Bisphenol A (BPA), current knowledge on the spatial distribution, potential sources and environmental risk assessment of other bisphenol analogues (BPs) remains limited. The occurrence, distribution and sources of seven BPs were investigated in the surface water and sediment from Taihu Lake and Luoma Lake, which are the Chinese shallow freshwater lakes. Because there are many industries and living areas around Taihu Lake, the total concentrations of ∑BPs were much higher than that in Luoma Lake, which is away from the industry-intensive areas. For the two lakes, BPA was still the dominant BPs in both surface water and sediment, followed by BPF and BPS. The spatial distribution and principal component analysis showed that BPs in Luoma Lake was relatively homogeneous and the potential sources were relatively simple than that in Taihu Lake. The spatial distribution of BPs in sediment of Taihu Lake indicated that ∑BPs positively correlated with the TOC content. For both Taihu Lake and Luoma Lake, the risk assessment at the sampling sites showed that no high risk in surface water and sediment (RQt < 1.0, and EEQt < 1.0 ng E2/L).


Assuntos
Compostos Benzidrílicos/análise , Sedimentos Geológicos , Lagos/química , Fenóis/análise , Poluentes Químicos da Água/análise , China , Ecologia , Monitoramento Ambiental , Sedimentos Geológicos/análise , Humanos , Análise de Componente Principal , Medição de Risco , Água/análise , Água/química
17.
Luminescence ; 32(8): 1488-1493, 2017 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-28590024

RESUMO

Here we report an easy and economical hydrothermal carbonization approach to synthesize the fluorescent nitrogen-doped carbon dots (N-CDs) that was developed using citric acid and triethanolamine as the precursors. The synthesis conditions were optimized to obtain the N-CDs with superior fluorescence performances. The as-prepared N-CDs are monodispersed sphere nanoparticles with good water solubility, and exhibited strong fluorescence, favourable photostability and excitation wavelength-dependent behavior. Furthermore, the in vitro cytotoxicity and cellular labeling of N-CDs were investigated using the rat glomerular mesangial cells. The results showed the N-CDs have more inconspicuous cytotoxicity and better biosafety in comparison with ZnSe quantum dots, although both targeted the cells successfully. Considering their admirable photostability, low toxicity and good compatibility, the as-obtained N-CDs could have potential applications in biosensors, cellular imaging, and other fields.


Assuntos
Materiais Biocompatíveis/química , Carbono/química , Corantes Fluorescentes/química , Imagem Molecular , Nitrogênio/química , Animais , Materiais Biocompatíveis/síntese química , Materiais Biocompatíveis/farmacologia , Linhagem Celular , Sobrevivência Celular/efeitos dos fármacos , Corantes Fluorescentes/síntese química , Corantes Fluorescentes/farmacologia , Pontos Quânticos , Ratos , Espectrometria de Fluorescência
18.
Sci Total Environ ; 599-600: 1090-1098, 2017 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-28511354

RESUMO

Since the production and use of BPA were regulated in China around 2008, several bisphenol analogues were widely used to substitute BPA in the manufacture of polycarbonates, epoxy resins, and plastics. However, there is limited understanding of the spatial distribution, potential sources and risk assessment for those bisphenol analogues. In this study, seven bisphenol analogues were investigated in water and sediment samples from Taihu Lake, China. Compared to the same lake in 2013 (range: 5.4-87ng/L for waters and 0.37-8.3ng/g dw for sediments), the samples from Taihu Lake contained comparatively higher BPs (2.0×102-9.5×102ng/L and 23-4.3×102ng/gdw) in 2016, indicating that the BPs levels in Taihu Lake have aggravated recently. In waters, BPAF has become the predominant congener in Taihu Lake, suggesting that BPAF was the most widely used substitute of BPA, recently. In sediments, BPA was the most abundant compound. Moderate or strong correlations between some individual BPs indicated that those BPs may have the common sources and/or similar environmental behavior. The strongly positive correlation between ∑BPs and TOC content indicated that TOC content was one of the major factors controlled the distribution of ∑BPs in the sediment. The risk assessment at the sampling sites showed no high eco-toxicity or estrogenic risk in Taihu Lake.


Assuntos
Monitoramento Ambiental , Sedimentos Geológicos/análise , Lagos/química , Fenóis/análise , Poluentes Químicos da Água/análise , China , Ecologia , Humanos , Medição de Risco
19.
Anal Sci ; 33(3): 293-298, 2017.
Artigo em Inglês | MEDLINE | ID: mdl-28302969

RESUMO

A sensitive non-derivatization method for the determination of the highly polar compound 3-aminopiperidine was developed using a mixed-mode column combined with a charged aerosol detector (CAD). Chromatographic conditions, including the type of detector, separation mode, and mobile phase composition, were optimized to achieve high sensitivity towards and sufficient retention of 3-aminopiperidine. Compared to the precolumn derivatization UV method, the current method showed higher recovery and greater simplicify. High sensitivity (LOQ <2.73 µg mL-1) and good precision (RSD of peak area <2%) were also observed in the current method. Furthermore, the parameters such as buffer solution and column bleed that affected the sensitivity of the CAD were investigated. Finally, the current method was applied for the determination of 3-aminopiperidine in linagliptin samples. This is a new non-derivative for the determination of 3-aminopiperidine, and constitutes a novel application of the CAD for the quantitative analysis of highly polar basic compounds.

20.
Colloids Surf B Biointerfaces ; 154: 142-149, 2017 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-28334691

RESUMO

A novel type of suspension array for multiplex detection of heavy metal ions with photonic crystal hydrogel microspheres was reported. The photonic crystal hydrogel microspheres have close-packed photonic crystal particles as their encoding units and ssDNA-functionalized hydrogel as the sensing units. The developed microspheres were successfully applied in multiplex detection of heavy metal ions.


Assuntos
Metais Pesados/análise , Cátions/análise , Cristalização , Sondas de DNA , DNA de Cadeia Simples , Corantes Fluorescentes , Humanos , Hidrogéis , Metais Pesados/toxicidade , Microesferas , Fenômenos Ópticos , Compostos Orgânicos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
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