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1.
Food Chem ; 370: 131353, 2022 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-34788964

RESUMO

A highly effective molecularly imprinted electrochemiluminescence sensor was constructed for prometryn determination in environmental and biological samples by using perovskite quantum dots coated with a molecularly imprinted silica layer (MIP/CsPbBr3-QDs) as the recognition and response element. MIP/CsPbBr3-QDs were immobilized on a glassy carbon electrode (GCE) through electropolymerization, and the electrochemiluminescence (ECL) response of MIP/CsPbBr3-QDs could be motivated under the condition of H2O2 as co-reactant. ECL signal was selectively quenched with prometryn by hindering electron transfer and directly proportional to the logarithm of prometryn concentration (0.10-500.0 µg/L) with a correlation coefficient of 0.9960. Limits of detection in fish and seawater samples were 0.010 µg/kg and 0.050 µg/L, respectively. Excellent recoveries of 88.0%-106.0% were acquired for fish and seawater samples with a relative standard deviation below 4.2%. The constructed MIECL sensor based on MIP/CsPbBr3-QDs showed good stability, accuracy, and precision for sensitive detection of prometryn in aquaculture products and environmental samples.


Assuntos
Impressão Molecular , Pontos Quânticos , Animais , Compostos de Cálcio , Peróxido de Hidrogênio , Limite de Detecção , Polímeros Molecularmente Impressos , Óxidos , Prometrina , Titânio
2.
J Phys Chem Lett ; : 11511-11519, 2021 Nov 19.
Artigo em Inglês | MEDLINE | ID: mdl-34797680

RESUMO

The configurational space of two-dimensional planar sp2 carbon has been systematically scanned by a random strategy combined with group and graph theory, and 1114 new carbon allotropes have been identified. These allotropes are energetically more favorable than most of the previously predicted 120 carbon allotropes. By fitting the HSE06 band structures of six old structures, we optimize the parameters for a general and transferable tight-binding model for high-throughput band structure calculations. We identified that there are 190 Dirac semimetals, 241 semiconductors, and 683 normal metals among the new allotropes. Interestingly, several stable low-energy carbon systems with exotic electronic properties are proposed, such as type III, type I/II mixed, and type I/III mixed semimetals, which are very rare in planar carbon systems. In particular, one nodal-line semimetal has been discovered among these thousands of allotropes, which is the first nodal-line semimetal in sp2 carbon systems. Our discoveries greatly enrich our knowledge of the structures and electronic properties of the two-dimensional carbon family.

3.
Water Res ; 204: 117632, 2021 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-34536686

RESUMO

The spatiotemporal variations, influencing factors and potential sources, as well as the ecological/health risks of polycyclic aromatic hydrocarbons (PAHs) were systematically investigated in seawater, sediment, and fish from Xiangshan Bay, China, one of the most important and oldest domestic marine aquaculture bases. The average concentrations of ΣPAHs in seawater, sediment and fish were 150 ± 70.0 ng/L, 276 ± 271 µg/kg (dry weight, dw), and 434 ± 151 µg/kg (dw), respectively. Naphthalene, phenanthrene, fluoranthene, benzo(b)fluoranthene and pyrene were the dominant contaminants in all samples. The highest PAH concentrations in the seawater and sediment samples occurred in the inner bay where the mariculture and industry are clustered. Seasonal differences were observed in the seawater samples but not in the sediment samples. Among all 15 fish species, large yellow croaker (Larimichthys crocea) (775 µg/kg (dw)), red drum (Sciaenops ocellatus) (749 µg/kg (dw)), and flathead grey mullet (Mugil cephalus) (637 µg/kg (dw)) had relatively high PAH accumulation concentrations in muscle tissue. According to the molecular diagnostic ratio method, the PAHs in seawater mainly originated from a mixed source of petroleum and combustion, whereas biomass/coal combustion sources were identified for sediment. The results obtained from the risk quotient (for seawater), sediment quality guidelines and toxic equivalence quotients (for seawater and sediment) methods showed that the ecological risks posed by PAHs were generally at a low to moderate level. Potentially toxic effects existed from PAH-contaminated fish consumption, and the resulting potential carcinogenic risk was also slightly higher than the recommended guidelines (10-6).


Assuntos
Hidrocarbonetos Policíclicos Aromáticos , Poluentes Químicos da Água , Animais , Ecossistema , Monitoramento Ambiental , Sedimentos Geológicos , Hidrocarbonetos Policíclicos Aromáticos/análise , Medição de Risco , Poluentes Químicos da Água/análise
4.
J Phys Chem Lett ; 12(36): 8889-8896, 2021 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-34498878

RESUMO

Based on first-principles calculations, the ground state configuration (Cmma-CH) of a hydrogenated biphenylene sheet ( Science 2021, 372, 852) is carefully identified from hundreds of possible candidates generated by RG2 code ( Phys. Rev. B. 2018, 97, 014104). Cmma-CH contains four inequivalent benzene molecules in its crystalline cell due to its Cmma symmetry. Hydrogen atoms bond to carbon atoms in each benzene with a boat-like (DDUDDU) up/down sequence and reversed boat-1 (UUDUUD) sequence in adjacent benzene rings. Cmma-CH is energetically less stable than the proposed allotropes of hydrogenated graphene, but the formation energy for hydrogenating a biphenylene sheet is remarkably lower than that for hydrogenating graphene to graphane. Our results of mechanical and dynamical stability also confirm that Cmma-CH is a stable 2D hydrocarbon, which is expected to be realized experimentally. Especially, biphenylene undergoes a transition from normal metal to a wide band gap insulator (4.645 eV) by hydrogenation to Cmma-CH, which has potential applications in nanodevices at elevated temperatures and high voltages.

5.
J Hazard Mater ; 416: 125931, 2021 08 15.
Artigo em Inglês | MEDLINE | ID: mdl-34492861

RESUMO

Contamination characteristics, equilibrium partitioning and risk assessment of phthalate esters (PAEs) were investigated in seawater, sediment and biological samples collected from the Xiangshan Bay area during an annual investigation between January and November 2019. PAE concentrations detected in the mariculture environment in surface seawater, sediment, and biological samples were 172-3365 ng/L, 190-2430 µg/kg (dry weight [dw]), and 820-4926 µg/kg (dw), respectively. The dominant congeners in different media included di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP). The inner bay and the bay mouth were the gathering area of PAEs and heavily influenced by the mariculture activities, river inputs, and anthropogenic activities. The bioaccumulation of PAEs demonstrated benthic feeding fishes with relatively high trophic levels concentrated high levels of phthalates. The mobility of PAEs in sediment-seawater showed that the transfer tendency of low-molecular weight species was from the sediment to the water, which was in contrast with those of high-molecular weight PAEs. DEHP, DiBP and DnBP had various degrees of ecological risks in the aquatic environment, whereas only the DiBP posed potential risks in sediments. The current assessment of carcinogenic and noncarcinogenic risks posed by fish consumption were within acceptable limits for humans.


Assuntos
Ésteres , Ácidos Ftálicos , Aquicultura , China , Dibutilftalato , Humanos , Ácidos Ftálicos/toxicidade , Plásticos/toxicidade , Medição de Risco
6.
Chem Biol Interact ; 347: 109616, 2021 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-34363818

RESUMO

The reproductive toxicity of endocrine-disrupting chemicals has become a matter of great concern. However, the potential toxicological mechanism of typical environmental estrogens, bisphenol A (BPA) and genistein (GEN), on adult ovary remains ambiguous. In this study, we used laying hens as the experimental model and aimed to clarify the effect of long-term exposure to safe reference doses of BPA and GEN on adult ovary. Results demonstrated that 1/10 no-observable-adverse effect-level dose (1/10 NOAEL, 500 µg/kg body weight [bw]/day) of BPA significantly reduced the production performance and caused the degeneration of follicles and stromal cells and the increase of atretic follicles. Moreover, 1/10 NOAEL dose of BPA undermined the redox homeostasis of the ovary through activating Keap1 and suppressing the Nrf2-signaling pathway (Nrf2, NQO1, and HO-1). On the contrary, GEN (20, 40 mg/kg bw/day) dramatically improved the antioxidant capacity of the ovary by regulating the Nrf2-Keap1 pathway, enhancing the activities of antioxidant-related enzymes (CAT, GSH-Px, and T-SOD), and inhibiting the excessive accumulation of lipid peroxidation products (MDA). Parallel in vitro studies confirmed that the differential role of BPA and GEN on ovarian redox balance was directly mediated by Nrf2-Keap1 antioxidant system. And GEN could ameliorate BPA-induced oxidative stress. Importantly, our research found that exposure to BPA and GEN altered estrogen receptor alpha (ERα) expression in the ovary. And the use of specific ERα agonist/antagonist confirmed that BPA and GEN have opposite regulatory effects on the Nrf2-Keap1 pathway by targeting ERα.


Assuntos
Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Genisteína/toxicidade , Ovário/efeitos dos fármacos , Estresse Oxidativo/efeitos dos fármacos , Fenóis/toxicidade , Transdução de Sinais/efeitos dos fármacos , Animais , Galinhas , Receptor alfa de Estrogênio/metabolismo , Feminino , Homeostase/efeitos dos fármacos , Proteína 1 Associada a ECH Semelhante a Kelch/metabolismo , Fator 2 Relacionado a NF-E2/metabolismo , Ovário/metabolismo , Ovário/patologia
7.
ACS Appl Mater Interfaces ; 13(34): 40249-40266, 2021 Sep 01.
Artigo em Inglês | MEDLINE | ID: mdl-34424682

RESUMO

Disruption of intestinal homeostasis is an important event in the development of inflammatory bowel disease (IBD), and genistein (GEN) is a candidate medicine to prevent IBD. However, the clinical application of GEN is restricted owing to its low oral bioavailability. Herein, a reactive oxygen species (ROS)-responsive nanomaterial (defined as GEN-NP2) containing superoxidase dismutase-mimetic temporally conjugated ß-cyclodextrin and 4-(hydroxymethyl)phenylboronic acid pinacol ester-modified GEN was prepared. GEN-NP2 effectively delivered GEN to the inflammation site and protected GEN from rapid metabolism and elimination in the gastrointestinal tract. In response to high ROS levels, GEN was site-specifically released and accumulated at inflammatory sites. Mechanistically, GEN-NP2 effectively increased the expression of estrogen receptor ß (ERß), simultaneously reduced the expression of proinflammatory mediators (apoptosis-associated speck-like protein containing a CARD (ASC) and Caspase1-p20), attenuated the infiltration of inflammatory cells, promoted autophagy of intestinal epithelial cells, inhibited the secretion of interleukin-1ß (IL-1ß) and tumor necrosis factor-α (TNF-α), modulated the gut microbiota, and ultimately alleviated colitis. In addition, the oral administration of these nanoparticles showed excellent safety, thereby providing confidence in the further development of precise treatments for IBD.

8.
Mar Pollut Bull ; 168: 112393, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33932843

RESUMO

In this study, marine mussels (Mytilus coruscus) were exposed to three typical PAEs (dimethyl phthalate [DMP], dibutyl phthalate [DBP] and di(2-ethylhexyl) phthalate [DEHP]) at a range of doses for different times to investigate the ecotoxicological effects. The accumulation of the three PAE congeners in M. coruscus exhibited the following trend: DEHP > DBP > DMP. The antioxidant response of mussel gonadal tissue was enhanced with increasing concentrations of PAEs. For the DBP and DEHP treatment groups, glutathione (GSH) worked in concert with antioxidant enzymes to protect cells against reactive oxygen species (ROS), while GSH played a prominent antioxidant role in the DMP-treated group. The metabolomics results revealed that PAE exposure disrupted the metabolic balance of mussels. Overall, PAEs affect the amino acid metabolism, lipid metabolism, energy metabolism, osmoregulation and nerve activities of mussels. Our results provide further insight into the toxicological effects of PAEs on marine organisms.


Assuntos
Mytilus , Ácidos Ftálicos , Animais , Bioacumulação , Dibutilftalato , Ésteres , Metabolômica
9.
Mar Environ Res ; 169: 105329, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-33892338

RESUMO

The high-density polyethylene (HDPE) and the polystyrene (PS), which are typical microplastic contaminants, are frequently detected in the environment and have potential hazard to environmental health. In this study, the accumulation, elimination, tissue distribution and potential effects of the HDPE and the PS in the mussels (Mytilus galloprovincialis) were evaluated. The HDPE and the PS were found in various tissues (digestive gland > gill > gonad ≈ muscle) with no difference in distribution patterns. The accumulation of the HDPE and the PS rapidly increased in the first 48 h exposure, and the accumulation of HDPE was higher than that of PS. After 144 h of elimination, most of the HDPE and the PS were cleared by mussels. In addition, the activities of superoxide dismutase (SOD), catalase (CAT) and the content of oxidized glutathione considerably increased, indicating that the HDPE and the PS induced oxidative stress and prevented oxidative damage in elimination. The metabolomic analysis suggested that exposure to HDPE and PS induced alterations in the metabolic profiles of mussel. Differential metabolites were involved in energy metabolism, lipid metabolism, tricarboxylic acid cycle and neurotoxic response., and Meanwhile, the PS had a lower effect on mussel metabolism during elimination, but the effect of HDPE was increased. Overall, this study elucidated that the HDPE and the PS caused adverse effects on the mussels and provided insights toward understanding the hazard of different microplastics on aquatic organisms.


Assuntos
Poluentes Ambientais , Mytilus , Poluentes Químicos da Água , Animais , Microplásticos , Estresse Oxidativo , Plásticos/toxicidade , Polietileno , Poliestirenos , Poluentes Químicos da Água/análise , Poluentes Químicos da Água/toxicidade
10.
Sci Total Environ ; 770: 144705, 2021 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-33736359

RESUMO

The pollution characteristics, spatiotemporal variation, sediment-water partitioning, and potential ecological risk assessment of phthalate esters (PAEs) in the sediment-seawater system of the Hangzhou Bay (HZB) in summer and autumn were researched. The sum of the concentrations of the 10 PAEs in seawater ranges from 7305 ng/L to 22,861 ng/L in summer and from 8100 ng/L to 33,329 ng/L in autumn, with mean values of 15,567 ± 4390 and 17,884 ± 6850 ng/L, respectively. The Σ16PAEs in the sediments are between 118 and 5888 µg/kg and 145 and 4746 µg/kg in summer and autumn, respectively. The level of PAEs in seawater varies with the seasons, but it is relatively stable in the sediments. Di(2-ethylhexyl) phthalate (DEHP), di-n-butyl phthalate (DnBP), and diisobutyl phthalate (DiBP) are the predominant PAE congeners in the HZB. The DnBP and DiBP concentrations in seawater are greater than the DEHP concentration, which is the opposite in the sediments. The sediment-seawater equilibrium distribution study indicates that the PAEs with medium molecular weights, such as DiBP, butyl benzyl phthalate, and DnBP, are near dynamic equilibrium in the sediment-seawater system; PAEs with high molecular weights (e.g., di-n-octyl phthalate and DEHP) tend to transfer from water to the sediments; and PAEs with low molecular weights (e.g., dimethyl phthalate, diethyl phthalate, and diamyl phthalate) tend to spread to seawater. The risk assessment results in seawater indicate that DEHP and DiBP might pose high potential risks to sensitive organisms, and DnBP might exhibit medium ecological risks. In the sediment, DiBP might display a high potential risk to fish, and the potential risk of DEHP is high in several sites.

11.
Food Chem ; 347: 129030, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33515968

RESUMO

A modified quick, easy, cheap, effective, rugged, and safe (QuEChERs) method for determining triazine herbicide residues in bivalves (Mussels, Scallops, Cockles) was developed. The use of molecularly imprinted polymers (MIPs) as a selective purification material during dispersive-solid phase extraction (d-SPE) increased the removal rate of pigments interference. With 4% acidic acetonitrile as the organic modifier, the modified QuEChERs method achieved good extraction rate of herbicide residues. The satisfactory recoveries (80%-118%) and RSDs (1.0%-11.6%) of herbicide residues were obtained at three spiked levels. The limits of quantification of herbicide residues ranged from 0.10 µg/kg to 1.59 µg/kg. Further, the herbicide residues in bivalves collected in the eastern coasts of China was analyzed. The developed QuEChERs procedure coupled with GC-MS/MS was successfully applied to the herbicide residues detection in bivalves, and due to the extensive use of herbicides and the large consumption of bivalves in globally, the ongoing risk evaluation is needed.


Assuntos
Bivalves/química , Resíduos de Praguicidas/análise , Extração em Fase Sólida/métodos , Triazinas/análise , Animais , China , Cromatografia Gasosa/métodos , Herbicidas/análise , Espectrometria de Massas em Tandem/métodos , Triazinas/isolamento & purificação
12.
Environ Pollut ; 271: 116362, 2021 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-33387782

RESUMO

Atrazine (ATR) is one of the most commonly used herbicides that could directly impair the growth and health of organisms in mariculture areas and adversely affect human health through the food chain. This study investigated the contaminant occurrence, migration, and transformation of ATR and three of its chlorinated metabolites, namely deethylatrazine (DEA), deisopropylatrazine (DIA), and didealkylatrazine (DDA), in surface seawater, sediment, and aquatic organisms from the Xiangshan Harbor. ATR was detected in all samples, while DIA and DDA were only respectively detected in aquatic and seawater samples. The distribution of ATR and its metabolites presented different patterns depending on the geographic location and showed a higher level in the aquaculture area than that in the non-aquaculture area. The bioaccumulation of ATR in aquaculture organisms showed that benthic organisms, such as Ditrema, and Sinonovacula constricta (Sin), had increased levels. The ecological risks indicated that ATR posed medium or high risks to algae in the water phase of the study area. The microcosm experiment showed that the main fate of ATR in the simulated microenvironment was sedimentation, which followed the first-order kinetic equation. The ATR in the sediment could be enriched 3-5 times in Sin, and its major metabolites were DEA and DIA.


Assuntos
Atrazina , Herbicidas , Aquicultura , Baías , Herbicidas/análise , Humanos , Água do Mar
13.
J Chromatogr A ; 1636: 461794, 2021 Jan 11.
Artigo em Inglês | MEDLINE | ID: mdl-33341433

RESUMO

A rapid, simple, and generic analytical method for the simultaneous determination of 140 undesirable low-weight pesticides and mycotoxins from different chemical classes in black tea was developed. The method involved swelling the sample in ammonium acetate buffer, extraction with acetonitrile-dimethyl sulfoxide, cleanup by dual dispersive solid-phase extraction (D-SPE) with the assistance of low-temperature centrifugation, and analysis by ultraperformance liquid chromatography coupled with electrospray ionization tandem mass spectrometry using multiple reaction monitoring mode. The interferences in the extract were eliminated by the combination of dual d-SPE using only C18 sorbent and anhydrous magnesium sulfate, which maintained the chromatographic column under the ideal condition for a long time and enabled satisfactory recoveries of hydrophobic and hydrophilic analytes simultaneously. Matrix-matched calibration curves were obtained for most target compounds with linear regression coefficients above 0.9900. The limits of quantification (LOQs) ranged within 0.5-10.0 µg/kg, which were usually sufficient to verify the compliance of products with legal tolerances. Satisfactory recoveries of 64.5%-138.1% were obtained in black ta samples with the relative standard deviation (RSD) values between 1.8 and 25.9%. The inter-day precision ranged within 2.2%-24.9%. For over 90% of the analytes, the recoveries were between 70% and 120%, with RSD values below 15.0%. The application of this method in routine monitoring programs can drastically reduce effort and time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Micotoxinas/análise , Praguicidas/análise , Espectrometria de Massas em Tandem/métodos , Chá/química , Acetonitrilas/química , Tampões (Química) , Dimetil Sulfóxido/química , Reprodutibilidade dos Testes , Extração em Fase Sólida , Espectrometria de Massas por Ionização por Electrospray
14.
Ecotoxicol Environ Saf ; 206: 111398, 2020 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-33010594

RESUMO

Bisphenol A (BPA) is an endocrine-disrupting chemical. Its influence on lipid homeostasis remains to be proven. In this study, the obese model of laying hens were induced using high-fat diet (HFD) to determine the lipid metabolism interference of BPA, especially its influence on estrogen receptors (ERs) and oxidative damage, at the dose of tolerable daily intake (TDI, 50 µg/kg body weight [BW]/day) and no observable adverse effect level (NOAEL, 5000 µg/kg BW/day). The results demonstrated that the TDI dose of BPA interacted with ERα more effectively than the NOAEL dose of BPA. The TDI dose of BPA increased the expression of ERα (esr1), which further changed the expression of lipid metabolism-related genes, such as cpt-1, lpl, creb1, and apov1. Furthermore, the abdominal fat rate, hematoxylin-eosin staining of adipocytes, and the average area of the hens were reduced. Therefore, the TDI dose of BPA played an estrogen-compensating role and weakened the effect of HFD on obesity in aged hens. By contrast, BPA at NOAEL dose exhibited great oxidative stress, which remarkably inhibited the activities of antioxidant-related enzymes (total superoxide dismutase and glutathione peroxidase) and promoted the excessive accumulation of lipid peroxidation products (malondialdehyde). Moreover, the increase in oxidative stress corresponded well with the increase in the expression of fat-forming genes (srebp-1, fas, acc, and ppar γ). That is, BPA at NOAEL may accelerate the process of fat formation.


Assuntos
Gordura Abdominal/efeitos dos fármacos , Compostos Benzidrílicos/toxicidade , Disruptores Endócrinos/toxicidade , Metabolismo dos Lipídeos/efeitos dos fármacos , Obesidade/induzido quimicamente , Fenóis/toxicidade , Gordura Abdominal/metabolismo , Adipócitos/efeitos dos fármacos , Adipócitos/metabolismo , Animais , Antioxidantes/metabolismo , Peso Corporal/efeitos dos fármacos , Galinhas/metabolismo , Dieta Hiperlipídica , Receptor alfa de Estrogênio/genética , Feminino , Metabolismo dos Lipídeos/genética , Masculino , Obesidade/genética , Obesidade/metabolismo
15.
J Nutr Biochem ; 83: 108438, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-32563803

RESUMO

Soy isoflavones (SIFs) are selective estrogen receptor modulators (SERMs) that have anti-inflammatory activities. Our previous study found that estrogen receptor α (ERα) directly regulates the NLRP3 transcription and NLRP3 inflammasome assembly. Therefore, we hypothesized that SIFs alleviate colitis via an ERα-dependent mechanism by targeting the NLRP3 inflammasome. The influence of SIFs on colitis and the potential mechanisms were thoroughly determined in this study. The results suggested that SIFs ameliorated dextran sodium sulfate (DSS)-induced body weight loss, reduced disease activity index and promoted the recovery of colon pathological damage in mice. Moreover, expression of the NLRP3 inflammasome was significantly inhibited, and the release of IL-1ß and IL-18 was suppressed by SIFs. Furthermore, ERα blockade ameliorated DSS-induced inflammatory responses in the intestine, and SIFs markedly suppressed the expression of ERα in a dose-dependent manner. Our study demonstrated that the protective therapeutic action of SIFs on DSS-induced colitis depended on inhibition of ERα and subsequent NLRP3 inflammasome activation, and SIFs are promising therapeutic agents for the treatment of colitis.


Assuntos
Anti-Inflamatórios/administração & dosagem , Colite/tratamento farmacológico , Receptor alfa de Estrogênio/imunologia , Inflamassomos/efeitos dos fármacos , Isoflavonas/administração & dosagem , Proteína 3 que Contém Domínio de Pirina da Família NLR/imunologia , Extratos Vegetais/administração & dosagem , Animais , Colite/genética , Colite/imunologia , Receptor alfa de Estrogênio/genética , Humanos , Inflamassomos/genética , Inflamassomos/imunologia , Interleucina-18/genética , Interleucina-18/imunologia , Interleucina-1beta/genética , Interleucina-1beta/imunologia , Masculino , Camundongos , Camundongos Endogâmicos C57BL , Proteína 3 que Contém Domínio de Pirina da Família NLR/genética , Soja/química
16.
Environ Pollut ; 265(Pt A): 114913, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32531649

RESUMO

Spatiotemporal variability in seawater, spatial variation in sediment, pollution characteristics, and risks related to 16 phthalate esters (PAEs) were investigated in the Yangtze River estuary and its adjacent East China Sea. The total concentrations of ΣPAEs in surface water were 0.588-17.7 µg L-1 in summer, 2.63-22.9 µg L-1 in winter, and 1.93-20.7 µg L-1 in spring, with average values of 2.05, 10.2, and 4.89 µg L-1, respectively. PAE concentrations exhibited notable seasonal variations with the highest value in winter and the lowest value in summer. The seasonal variation in PAE concentrations may be influenced by runoff and diluted water from the Yangtze River. The chemical composition of PAEs showed that di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP) had significantly higher (p < 0.05) concentrations than the other congeners and were the most abundant PAE species in sediment and seawater in all three seasons. In addition, DnBP and DiBP were the two main congeners in seawater, and DEHP concentrations were higher in sediment than in seawater. DEHP had higher potential risks to sensitive organisms in water environment than DnBP and DiBP, and DiBP and DnBP which presented high levels of risk in sedimentary environment. DMP and DEP in watery and sedimentary environments and DEHP in sedimentary environment showed no or low risks to sensitive organisms.


Assuntos
Ácidos Ftálicos/análise , Rios , China , Dibutilftalato/análise , Ésteres/análise , Estuários , Água
17.
Sensors (Basel) ; 20(3)2020 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-32046019

RESUMO

A highly selective and sensitive molecularly imprinted electrochemiluminescence (MIECL) sensor was developed based on the multiwall carbon nanotube (MWCNT)-enhanced molecularly imprinted quantum dots (MIP-QDs) for the rapid determination of cyfluthrin (CYF). The MIP-QDs fabricated by surface grafting technique exhibited excellent selective recognition to CYF, resulting in a specific decrease of ECL signal at the MWCNT/MIP-QD modified electrode. Under optimal conditions, the MIECL signal was proportional to the logarithm of the CYF concentration in the range of 0.2 µg/L to 1.0 × 103 µg/L with a determination coefficient of 0.9983. The detection limit of CYF was 0.05 µg/L, and good recoveries ranging from 86.0% to 98.6% were obtained in practical samples. The proposed MIECL sensor provides a novel, rapid, high sensitivity detection strategy for successfully analyzing CYF in fish and seawater samples.

18.
Chemosphere ; 246: 125622, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31918075

RESUMO

Molecularly imprinted polymers (MIPs) are attracting substantial interest as artificial plastic antibodies because of their biometric capability for targeting small molecules. In this study, molecularly imprinted silica material-coated quantum dots (MIS-QDs) with selective recognition capability to okadaic acid (OA) were developed and characterized. The synthesized MIS-QDs with specific imprinting cavities exhibited excellent recognition capability similar to those of biological antibodies and high fluorescence (FL) quenching selectivity for OA. Furthermore, the MIS-QDs with unsaturated bonds were immobilized onto the surface of 96-well microplates by cold plasma-induced grafting. A novel direct competitive microplate assay strategy was then proposed. The FL quenching properties of the developed microplate assay showed an excellent linear relationship with OA in the range of 10.0-100.0 µg/kg with a correlation coefficient of 0.9961. The limit of detection for OA was 0.25 µg/kg in the shellfish samples. The mean quantitative recoveries were 92.5%-101.0% and 92.9%-101.3%, with relative standard deviations of <7.7% and 7.6% for pure solvents and purified shellfish samples, respectively. The established microplate assay strategy can be used as a rapid and high-throughput method for analyzing OA marine toxins in biological samples.


Assuntos
Análise em Microsséries/métodos , Impressão Molecular/métodos , Ácido Okadáico/isolamento & purificação , Pontos Quânticos/química , Animais , Fluorescência , Toxinas Marinhas/análise , Ácido Okadáico/análise , Frutos do Mar , Dióxido de Silício/química
19.
Artigo em Inglês | MEDLINE | ID: mdl-31931332

RESUMO

A rapid, simple, and generic analytical method that could simultaneously determine 291 undesirable low molecular weight chemical contaminants from different drug families in protein powder, such as veterinary drugs and pesticides, etc, had been developed. This method comprised the extraction with acetonitrile-dimethyl sulfoxide (DMSO), clean-up through dispersive solid phase extraction (D-SPE) and low temperature filtration, and analysis by ultra-performance liquid chromatography coupled with electrospray ionization tandem mass spectrometry at multiple-reaction monitoring mode. Acetonitrile-DMSO was more generic than acetonitrile or methanol for the extraction of large-scale organic chemical contaminants with different polarities in protein powder. Most interferences in the extract were eliminated by the combination of D-SPE and low temperature filtration, which simultaneously provided satisfactory recoveries of both hydrophobic and hydrophilic analytes. In particular, besides the purification function, the sorbent of D-SPE also played an important role in grinding samples to improve extraction efficiency during homogenization. This streamlined approach allowed the processes of extraction and the main purification were carried out in one-step, and dramatically reduced sample preparation turnaround times and solvent consumption. For quantification, matrix-fortified calibration curves showed competent linearity for most of the target compounds with linear regression coefficients (r) higher than 0.9900, except for two analytes. The limits of quantification ranged from 0.1 µg/kg to 50 µg/kg, which was usually sufficient to verify the compliance of products with legal tolerances. The average recoveries for spiked protein powder ranged from 65.6% to 142.2% with associated RSD values between 0.5% and 28.5%. For over 90% of the analytes, the recoveries were between 70% and 120% with RSD values in the range of 1%-15%. Applying this method in routine monitoring programs would drastically reduce both effort and time.


Assuntos
Cromatografia Líquida de Alta Pressão/métodos , Proteínas na Dieta , Resíduos de Drogas/análise , Contaminação de Alimentos/análise , Espectrometria de Massas em Tandem/métodos , Proteínas na Dieta/análise , Proteínas na Dieta/normas , Suplementos Nutricionais/análise , Suplementos Nutricionais/normas , Modelos Lineares , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
20.
Environ Pollut ; 259: 113802, 2020 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-31896480

RESUMO

The spatial and temporal distribution, congener profiles and ecological risk of phthalic acid esters (PAEs) were investigated in the seawater and sediment samples from the East China Sea in spring and autumn. The average concentrations of ΣPAEs in water samples were 3.16 ± 2.16 µg L-1 in autumn and 1.63 ± 1.20 µg L-1 in spring. The ΣPAEs in sediment was much higher than that in seawater, with an average value of 7.36 ± 6.70 mg kg-1 (dw). PAEs levels in the sea-surface microlayer (SML) in spring were 3.61 ± 3.36 µg L-1, indicating that the PAEs were noticeably concentrated in the SML, with an average enrichment factor of 2.10. Among the 16 PAE congeners, di-n-butyl phthalate (DnBP), diisobutyl phthalate (DiBP), and di(2-ethylhexyl) phthalate (DEHP) were the preponderant PAEs in both sediment and seawater samples. Additionally, PAE concentrations in autumn were higher than those in spring, and this difference resulted mainly from the terrigenous input and marine transportation. The horizontal distributions of PAEs showed an opposite distribution pattern to salinity and temperature, a pattern which might be influenced by the inputs of fresh water. The vertical distributions of ΣPAEs were characterized by high concentrations in the surface waters, with a slight decrease with depth, and then an increase close to the seabed. The results of ecological risk in the water-phase showed that the level of potential risk followed the order of DEHP > DiBP and DnBP > DMP and DEP, which posed a high (DEHP), medium (DiBP and DnBP) and low (DMP and DEP) risk to the sensitive organisms, respectively. For the sediment-phase, DiBP and DnBP represented a high risk to the sensitive organisms, whereas DMP, DEP and DEHP had only a low risk.


Assuntos
Ésteres , Ácidos Ftálicos/análise , Poluentes Químicos da Água/análise , China , Dibutilftalato , Monitoramento Ambiental , Medição de Risco , Rios , Água do Mar
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