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BACKGROUND: Hepatocellular carcinoma (HCC) is an aggressive malignant tumor with poor prognosis. Using high-throughput sequencing, we identified a novel circRNA, circGNAO1, which is downregulated in HCC tissues compared to adjacent tissues. However, the potential functions and mechanisms of circGNAO1 in HCC metastasis remain unclear. METHODS: qRT-PCR was used to detect the expression of circGNAO1, miR-182-5p, and FOXO1 in HCC cells and tissues. Bioinformatics analysis, RNA pull-down assyas, and dual-luciferase reporter assays were employed to verify the interaction between circGNAO1 and miR-182-5p. Functional experiments were conducted using circGNAO1 overexpression and knockdown cell lines, including Transwell, wound healing, and EdU assays. Liver metastasis models and subcutaneous xenograft mouse models were established to analyze the effect of circGNAO1 on HCC metastasis and growth in vivo. RESULTS: High-throughput sequencing and qRT-PCR results showed that the expression of circGNAO1 dramatically decreased in HCC tissues. Functionally, in vivo and in vitro experiments verified that overexpression of circGNAO1 inhibited the proliferation, migration, invasion and EMT of HCC cells, while knockdown of circGNAO1 promoted these behaviors. Mechanistically, we have demonstrated that circGNAO1 functions as a sponge for miR-182-5p to regulate FOXO1 expression, thereby activating the TGF-ß/Smad3 signaling pathway and EMT process. CONCLUSIONS: circGNAO1 suppresses the progression and metastasis of HCC through the miR-182-5p/FOXO1 axis, and circGNAO1 may be an efficient therapeutic target in HCC.
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Micro-nano plastics (MNPs) pollution is currently a hot topic of global concern. However, there is still a lack of reliable analytical methods for completely quantitative analysis of MNPs, especially nanoplastics. This study proposes meniscus self-assembly enrichment method, which deposits nanoplastics more uniformly in a specific area. The meniscus self-assembly method greatly overcomes the agglomeration or dispersion of nanoplastics caused by traditional enrichments, and facilitates particles counting. This study investigates the effect of key parameters (e.g. time and initial concentration) on meniscus self-assembly enrichment performance. Besides, due to the large size difference between MNPs, it leads to incomplete quantification analysis when MNPs are counted at the same scale. In response to this problem, this study proposes a one-stop method to count MNPs separately through filtering. The plastics (>1 µm) are collected on the filter paper, then plastics (<1 µm) in the filtrate are homogeneously enriched by meniscus self-assembly, and finally statistically counted by scanning electron microscopy (SEM). The migration of MNPs from take-out plastic containers are detected, with microplastics of 460.55 particles/mL and nanoplastics of 4196.61 particles/mL found. The method has the advantages of saving time and effort, economic efficiency and comprehensive statistics compared with the traditional method.
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Sarcoidosis is a systemic granulomatous disease characterized by non-caseating epithelioid cell granulomas. One of its immunological hallmarks is the differentiation of CD4 + naïve T cells into Th1/Th17 cells, accompanied by the release of numerous pro-inflammatory cytokines. The TL1A/DR3 signaling pathway plays a crucial role in activating effector lymphocytes, thereby triggering pro-inflammatory responses. The primary aim of this investigation was to scrutinize the impact of anti-TL1A monoclonal antibody on the dysregulation of Th1/Th17 cells and granuloma formation in sarcoidosis. Initially, the abnormal activation of the TL1A/DR3 signaling pathway in pulmonary tissues of sarcoidosis patients was confirmed using qPCR and immunohistochemistry techniques. Subsequently, employing a murine model of sarcoidosis, the inhibitory effects of anti-TL1A monoclonal antibody on the TL1A/DR3 signaling pathway in sarcoidosis were investigated through qPCR, immunohistochemistry, and Western blot experiments. The influence of anti-TL1A monoclonal antibody on granulomas was assessed through HE staining, while their effects on sarcoidosis Th1/Th17 cells and associated cytokine mRNA levels were evaluated using flow cytometry and qPCR, respectively. Immunofluorescence and Western blot experiments corroborated the inhibitory effects of anti-TL1A monoclonal antibody on the aberrant activation of the PI3K/AKT signaling pathway in sarcoidosis. The findings of this study indicate that the TL1A/DR3 signaling pathway is excessively activated in sarcoidosis. Anti-TL1A monoclonal antibody effectively inhibit this abnormal activation in sarcoidosis, thereby alleviating the dysregulation of Th1/Th17 cells and reducing the formation of pulmonary granulomas. This effect may be associated with the inhibition of the downstream PI3K/AKT signaling pathway. Anti-TL1A monoclonal antibody hold promise as a potential novel therapeutic intervention for sarcoidosis.
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Anticorpos Monoclonais , Granuloma , Fosfatidilinositol 3-Quinases , Proteínas Proto-Oncogênicas c-akt , Sarcoidose , Transdução de Sinais , Células Th1 , Células Th17 , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral , Animais , Células Th1/imunologia , Células Th17/imunologia , Transdução de Sinais/efeitos dos fármacos , Humanos , Anticorpos Monoclonais/farmacologia , Anticorpos Monoclonais/uso terapêutico , Fosfatidilinositol 3-Quinases/metabolismo , Fosfatidilinositol 3-Quinases/imunologia , Granuloma/imunologia , Granuloma/tratamento farmacológico , Proteínas Proto-Oncogênicas c-akt/metabolismo , Proteínas Proto-Oncogênicas c-akt/imunologia , Feminino , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/metabolismo , Membro 15 da Superfamília de Ligantes de Fatores de Necrose Tumoral/imunologia , Masculino , Sarcoidose/imunologia , Sarcoidose/tratamento farmacológico , Camundongos , Adulto , Pessoa de Meia-Idade , Membro 25 de Receptores de Fatores de Necrose Tumoral/metabolismo , Membro 25 de Receptores de Fatores de Necrose Tumoral/imunologia , Pulmão/imunologia , Pulmão/patologia , Citocinas/metabolismo , Citocinas/imunologia , Modelos Animais de Doenças , Camundongos Endogâmicos BALB CRESUMO
Sepsis is a systemic inflammatory response syndrome caused by trauma or infection, which can lead to multiple organ dysfunction. In severe cases, sepsis can also progress to septic shock and even death. Effective treatments for sepsis are still under development. This study aimed to determine if targeting the PI3K/Akt signaling with CAL-101, a PI3K p110δ inhibitor, could alleviate lipopolysaccharide (LPS)-induced sepsis and contribute to immune tolerance. Our findings indicated that CAL-101 treatment improved survival rates and alleviated the progression of LPS-induced sepsis. Compared to antibiotics, CAL-101 not only restored the Th17/regulatory T cells (Treg) balance but also enhanced Treg cell function. Additionally, CAL-101 promoted type 2 macrophage (M2) polarization, inhibited TNF-α secretion, and increased IL-10 secretion. Moreover, CAL-101 treatment reduced pyroptosis in peritoneal macrophages by inhibiting caspase-1/gasdermin D (GSDMD) activation. This study provides a mechanistic basis for future clinical exploration of targeted therapeutics and immunomodulatory strategies in the treatment of sepsis.
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Classe I de Fosfatidilinositol 3-Quinases , Camundongos Endogâmicos C57BL , Piroptose , Sepse , Linfócitos T Reguladores , Células Th17 , Animais , Camundongos , Classe I de Fosfatidilinositol 3-Quinases/antagonistas & inibidores , Classe I de Fosfatidilinositol 3-Quinases/metabolismo , Macrófagos/imunologia , Macrófagos/efeitos dos fármacos , Macrófagos/metabolismo , Macrófagos Peritoneais/imunologia , Macrófagos Peritoneais/efeitos dos fármacos , Macrófagos Peritoneais/metabolismo , Inibidores de Fosfoinositídeo-3 Quinase/farmacologia , Piroptose/efeitos dos fármacos , Sepse/imunologia , Sepse/tratamento farmacológico , Transdução de Sinais/efeitos dos fármacos , Linfócitos T Reguladores/imunologia , Linfócitos T Reguladores/efeitos dos fármacos , Células Th17/imunologia , Células Th17/efeitos dos fármacosRESUMO
Marine microorganisms have been reported to degrade microplastics. However, the degradation mechanisms are still poorly understood. In this study, a bacterium Roseibium aggregatum ZY-1 was isolated from seawater, which can degrade poly(butylene adipate-co-terephthalate) (PBAT). The PBAT-PLA(polylactic acid, PLA) films, before and after degradation, were characterized by scanning electron microscope (SEM) and Fourier transform infrared spectrometer (FTIR), the weight loss rate and water contact angle were measured. The results indicate that ZY-1 colonized on PBAT-PLA film, changed the functional groups and decreased water contact angle of PBAT-PLA film. Moreover, liquid chromatography mass spectrometry (LC-MS) analysis reveales that PBAT was degraded into its oligomers (TB, BTB) and monomers (T, A) during 10 days, and adipic acid (A) could be used as a sole carbon source. The whole genome sequencing analyses illustrate the mechanisms and enzymes such as PETase, carboxylesterases, arylesterase (PpEst) and genes like pobA, pcaBCDFGHIJKT, dcaAEIJK, paaGHJ involved in PBAT degradation. Therefore, the R. aggregatum ZY-1 will be a promising candidate of PBAT degradation.
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Alcenos , Ácidos Ftálicos , Plásticos , Poliésteres , Poliésteres/química , Adipatos/química , Bactérias/metabolismo , ÁguaRESUMO
A method is proposed to fabricate a novel capillary surface-enhanced Raman scattering (SERS) substrate integrating sampling and detection based on meniscus evaporation self-assembled technology, named Meniscus@AgNPs@Capillary substrate. Ag nanoparticles (AgNPs) were arranged in the inner wall of the capillary through meniscus evaporation. The parameters which might affect the deposition of AgNPs during evaporation were investigated, including the evaporation temperature, self-assembly time, the ratio of silver sol to ethanol, and capillary length. The enhancement effect of SERS under different fabrication conditions was investigated using rhodamine 6G (R6G) as a Raman probe. Moreover, the optimal fabricated Meniscus@AgNPs@Capillary substrate was applied to the detection of several environmental pollutants such as polystyrene nanoplastics (PSNPs) and various antibiotics, with limits of detection (LOD) of 10 µg/L and 1 µg/L, respectively. The Meniscus@AgNPs@Capillary substrate presented the advantages of time and effort saving, high sensitivity, and on-site sampling and testing.
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Carbendazim (CBZ) is a widespread fungicide used in crop protection, but the CBZ residues in drinking water, fruits, and vegetables can also cause adverse impacts on public health due to direct exposure. In this paper, a ternary synergistic composite of bimetallic CoCu nanoparticles anchored on covalent organic framework/single-walled carbon nanotube (CoCu/COF/SWCNT) was prepared and further applied as an electrochemical sensing platform for detecting CBZ. The sensor showed a sensitive response performance toward CBZ oxidation, as a result of the enhanced charge transfer ability, large electrochemically active surface area, and high electro-catalytic activity from the rational integration of the ternary components in CoCu/COF/SWCNT. Under the optimal conditions, the proposed sensor exhibited a detection range of 0.001 to 10 µM and a limit detection of 0.65 nM for CBZ detection. In addition, the sensor displayed practical feasibility for the determination of CBZ in water and pear samples with a recovery of 96.1 % to 102.1 %.
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Microplastics (MPs) and Nanoplastics (NPs) accumulated in the environment have been identified as a major global issue due to their potential harm to wildlife. Current research in the detection of MPs is well established. However, the detection of NPs remains challenging. The aim of this paper is to investigate the detection of polystyrene (PS) NPs on a super-hydrophobic substrate using surface-enhanced Raman spectroscopy (SERS) technology after high-speed centrifugation of PS NPs and AgNPs. The hydrophobic substrate reduces the contact area of droplet, concentrating PS NPs and AgNPs on a small spot, which eliminates the random distribution of nano particles. The condensed PS NPs and AgNPs improve the SERS intensity, reproductivity and detection sensitivity. The results show that SERS measurement on a hydrophobic substrate could significantly improve the detection sensitivity of PS NPs, with the detection limits of PS NPs as low as 0.5 mg/L (500 nm PS NPs) and 1 mg/L (100 nm PS NPs). The study provides an effective and rapid method for the detection of NPs at trace concentration, demonstrating more possibility for the future detection of trace NPs in the aquatic environment.
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Nanopartículas Metálicas , Nanopartículas , Poluentes Químicos da Água , Poliestirenos/química , Microesferas , Microplásticos , Nanopartículas Metálicas/química , Prata/química , Plásticos , Análise Espectral Raman/métodos , Interações Hidrofóbicas e Hidrofílicas , Nanopartículas/química , Poluentes Químicos da Água/químicaRESUMO
Oxide supported noble metals are extensively investigated for ambient formaldehyde oxidation, and the Ag-CoOx complex is one promising combination in terms of cost and activity. Further, we previously observed that cooperating Ag with Li + greatly boosted formaldehyde degradation on CoOx. Yet, there is still room for improvement in removal efficiency, mineralization capacity and resistance to severe conditions. These objectives could be realized via strategically formulating the Li+ sites of Li-CoOx composite in this sister study. Three samples with Li + ---Co3+-O2- connections (L-CO), spinel Li+ (LCO-S) and layered Li+ (LCO-L) were obtained at low (300 °C), moderate (500 °C) and high (700 °C) temperatures, respectively. The specific Li+ positions and componential interaction were demonstrated by Hyperspectral imaging (HSI), XRD, SEM, TEM, HAADF mapping, UV-vis DRS and XPS. Moreover, the effect of reactive oxygen exposure on catalytic oxidation of formaldehyde (330-350 mg/m3) was disclosed through CO-TPR and O2-TPD. Compared with the LCO-S and LCO-L, L-CO exhibited dominant formaldehyde degradation due to the larger content of surface oxygen. After Ag decoration, the Li+---Co3+-O2- connections uniquely caused a strong binding of Ag species with catalyst host, which boosted the amount of reactive oxygen and finally resulted in an even higher elimination of â¼73% (CO2 yield = â¼21%), 47% higher than that of the L-CO (CO2 yield = â¼6%). But in contrast, the Ag@LCO-S only achieved â¼53% removal (CO2 yield = â¼9%) and Ag modification was powerless in altering the inertness of LCO-L, demonstrating that the chemical environment of alkali metal is crucial to effectively tuning the catalyst activity. The advantage of Ag@L-CO in formaldehyde depollution was further reflected from its much better resistance to moisture and aromatic compound omnipresent in indoor air. For the first time, this study extended the understanding of the alkali-metal-promoted formaldehyde oxidation reaction to an in-depth level.
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Dióxido de Carbono , Formaldeído , Oxirredução , Formaldeído/química , Óxidos/química , Oxigênio/químicaRESUMO
As a typical disinfectant, the use of benzyl dodecyl dimethyl ammonium bromide (BDAB) has dramatically increased since the emergence of SARS-CoV-2, posing a threat to environmental balance and human health. Screening BDAB co-metabolic degrading bacteria is required for efficient microbial degradation. Conventional methods for screening co-metabolic degrading bacteria are laborious and time-consuming, especially when the number of strains is large. This study aimed to develop a novel method for the rapid screening of BDAB co-metabolic degrading bacteria from the cultured solid medium using near-infrared hyperspectral imaging (NIR-HSI) technology. Based on NIR spectra, the concentration of BDAB in the solid medium can be well predicted by partial least squares regression (PLSR) models, non-destructively and rapidly, with Rc2 > 0.872 and Rcv2 > 0.870. The results show that the predicted BDAB concentrations decrease after degrading bacteria utilization, comparing with the regions where no degrading bacteria grew. The proposed method was applied to directly identify the BDAB co-metabolic degrading bacteria cultured on the solid medium, and two kinds of co-metabolic degrading bacteria RQR-1 and BDAB-1 were correctly identified. This method provides a high-efficiency method for screening BDAB co-metabolic degrading bacteria from a large number of bacteria.
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Compostos de Amônio , COVID-19 , Humanos , Imageamento Hiperespectral , Espectroscopia de Luz Próxima ao Infravermelho/métodos , SARS-CoV-2 , Tecnologia , Análise dos Mínimos Quadrados , BactériasRESUMO
Sarcoidosis is a multisystem inflammatory disease characterized by the development of Th1/Th17/regulatory T cells (Tregs)-related non-caseating granulomas. Phosphoinositide-3 kinases δ/γ (PI3Kδ/γ) play an important role in the maintenance of effective immunity, especially for Tregs homeostasis and stability. In the present study, superoxide dismutase A (SodA) stimulation was used to establish the sarcoidosis mouse model. The second immune stimulus was accompanied by CAL-101 (PI3Kδ inhibitor) or AS-605240 (PI3Kδ/γ inhibitor) treatment. To detect the effect of the PI3Kδ/γ inhibitor on the morphology of pulmonary granuloma and the activation of the PI3K signaling pathway, hematoxylin and eosin staining and immunofluorescence and western blotting was used, respectively. Fluorescence-activated cell sorting analysis and reverse transcription-quantitative PCR were adopted to detect the effect of the PI3Kδ/γ inhibitor on the SodA-induced sarcoidosis mouse model in respect to immune cell disorder and the function of Treg cells, with CD4+CD25- T cells and CD4+CD25+ T cells sorted by magnetic cell sorting. The results demonstrated that the inhibition of PI3Kδ/γ by transtracheal CAL-101/AS-605240 administration facilitated pulmonary granuloma formation. These therapeutic effects were associated with certain mechanisms, including suppressing the aberrantly activated PI3K/Akt signaling in both pulmonary granuloma and Tregs, particularly rescuing the suppressive function of Tregs. Notably, CAL-101 was more effective in immune modulation compared with AS-605240 and could overcome the aberrantly activated Akt in the lung and Tregs. These results suggest that PI3K/Akt signaling, especially the PI3Kδ subunit, can play a key role in optimal Tregs-mediated protection against pulmonary sarcoidosis. Therefore, transtracheal usage of PI3Kδ/γ inhibitors is an attractive therapy that may be developed into a new immune-therapeutic principle for sarcoidosis in the future.
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The microalgae located near the estuary of the Liaohe River along the coast of Panjin have long been in an area with large fluctuations in salinity, temperature, and nutrients, and have high-quality alternatives for high-value metabolites. Three strains of microalgae were screened and the biomass of microalgae could be optimized 0.313-0.790 g L-1 in 10 L bioreactor. The determination results of bioactive substances in these three microalgae showed that, the amount of fucoxanthin in the growth phase II (14 days) was maximum, at 5.354, 6.284 and 14.837 mg g-1 respectively. The diatoxanthin of Dut-wj-J1 in growth phase III (21 days) could reach 5.158 mg g-1. Dut-wj-J4 had the highest lipid production efficiency (9.45 mg L-1 d-1) followed by Dut-wj-J2 (8.49 mg L-1 d-1) and Dut-wj-J1 (8.18 mg L-1 d-1) respectively. These bioactive substances have inhibition zones of 7-13 mm against all four strains of bacteria ie., Acetobacter, Rhodococcus erythropolis, Escherichia coli and Bacillus subtilis Cohn respectively. In addition, these microalgae can play a potential role in nutrient enrichment in eutrophic seawater. The NO3- degradation rates of these three algae in the first 14 days were 75.0 %, 45.8 % and 100 % respectively, as well as the PO4- degradation rates in the first 7 days were 94.8 %, 100 % and 80.9 % respectively. This work manifests the plasticity of algae isolated from the Bohai Sea and provides useful insights for further joint production of bioactive substances.
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Diatomáceas , Microalgas , Água do Mar/química , Microalgas/metabolismo , Nutrientes , Biomassa , Antibacterianos/metabolismo , Nitrogênio/metabolismoRESUMO
The use of disinfectants made from quaternary ammonium compounds (QACs) has greatly increased since the outbreak of SARS-CoV-2. However, the effect of QACs on wastewater treatment performance is still unclear. In this study, a commonly used QAC, i.e., benzyl dodecyl dimethyl ammonium bromide (BDAB), was added to a moving-bed biofilm reactor (MBBR) to investigate BDAB's effect on nutrient removal. When the BDAB concentration was increased to 50 mg L-1, the ammonia removal efficiency (ARE) greatly decreased, as did the nitrate production rate constants (NPR). This inhibition was partly recovered by decreasing the BDAB concentration to 30 mg L-1. Metagenomic sequencing revealed the functional genera present during different stages of the control (Rc) and BDAB-added reactors (Re). The enriched genera (Rudaea, Nitrosospira, Sphingomonas, and Rhodanobacter) in Rc mainly related to the nitrogen metabolism, while the enriched genera in Re was BDAB-concentration dependent. Functional genes analysis suggested that a lack of ammonia oxidase-encoding genes (amoABC) may have caused a decrease in ARE in Re, while the efflux pump-encoding genes emrE, mdfA, and oprM and a gene encoding BAC oxygenase (oxyBAC) were responsible for BDAB resistance. The increase in the total abundance of antibiotic resistance genes (ARGs) in Re revealed a potential risk arising from BDAB. Overall, this study revealed the potential effect and ecological risks of BDAB introduction in WWTPs.
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COVID-19 , Compostos de Amônio Quaternário , Humanos , Amônia/análise , Bactérias , Biofilmes , Reatores Biológicos , Desnitrificação , Nitrogênio/análise , SARS-CoV-2 , GenômicaRESUMO
To obtain a versatile formaldehyde oxidation material, simultaneously increasing the oxidative ability, recyclability and deactivation repellence (e.g., enduring the interference from moisture and aromatic compound omnipresent in indoor air) is of great significance. Herein, the above properties of α-MnO2 were synchronously updated via one step treatment in oxalic acid (H2C2O4), and an in-depth understanding of the surface properties-performance relationship was provided by systematic characterizations and designed experiments. Compared with the pristine sample, XPS, ESR, O2-TPD, CO-TPR and pyridine-IR reveal that H2C2O4 created substantial Mn3+ species on surface, exposing a higher coverage of oxygen vacancies that actively participated in the dissociative activation of gas-phase O2 into reactive chemically adsorbed oxygen (OC), and the abundant Lewis acid sites further enabled the effective O2 activation process. The large amount of oxygen OC promoted the HCHO-to-CO2 conversion and inhibited the accumulation of formate that required a high temperature of 170 °C to be eliminated, thus conspicuously improving the α-MnO2's thermal recovery. The combined H2O-TPD, H2O-preadsorbed CO-TPR, C6H6-TPD and C6H6-preadsorbed CO-TPR investigations shed light on the H2C2O4-induced water and benzene resistance. The notably weakened water and benzene binding strength with the H2C2O4-modified surface together with the unrestrained oxygen OC accounted for the outstanding anti-deactivation performance.
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Óxidos , Água , Óxidos/química , Ácido Oxálico , Temperatura , Compostos de Manganês/química , Benzeno , Oxigênio/química , Catálise , Formaldeído/química , Estresse OxidativoRESUMO
Online monitoring of antibiotics in the environment attracts more and more attention. Surface-enhanced Raman scattering (SERS) is a promising technique for the detection of trace amounts of antibiotics in the environment, which is fast, non-invasive and sensitive. To investigate the enrichment of trace amounts of antibiotics in water, polyethylene microplastics (PE MPs) were prepared as sorbents to simply concentrate enrofloxacin, ciprofloxacin hydrochloride monohydrate and triclosan in water, followed by the SERS measurement of antibiotics extract washed from MPs on an AgNPs@Si SERS substrate. Limit of detection of Rhodamine 6G is 2.1 × 10-12 M achieved from the AgNPs@Si SERS, indicating a high enhancement. The detection results show that SERS peaks of the antibiotics could be observed from the spectra of the extracts eluted from MPs, indicating MPs could adsorb and desorb antibiotics from water. Besides, for enrofloxacin and triclosan, the intensity of SERS measured from the MPs extracts are higher than that of directly from the spiked water, demonstrating the proposed method could lower the detectable concentration of hydrophobic antibiotics in water. Moreover, the proposed MPs sorbents combined with SERS method was applied to detect the antibiotics in real river water, with minimal detection of 10-10 M, 10-8 M, and 10-8 M achieved for enrofloxacin, ciprofloxacin hydrochloride monohydrate and triclosan, respectively. The proposed method provides a promising simple, rapid and low reagent consuming means for monitoring antibiotics in water.
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Antibacterianos , Triclosan , Antibacterianos/análise , Ciprofloxacina , Enrofloxacina , Microplásticos , Plásticos , Polietilenos , Prata/química , Análise Espectral Raman/métodos , Tecnologia , ÁguaRESUMO
Surface Enhanced Raman Spectroscopy (SERS) is a highly sensitive detection method, however, it is still challenging to directly detect florfenicol due to its low Raman activity. To solve this problem, we present a novel sensor for selective detection of florfenicol residue in milk using gap-enhance Raman tags (GERTs) competitive immunoassay. In this nanosensor, Raman reporters 4-mercaptobenzoic acid (4MBA) were embedded in the 1 nm gap of Au core-gap-Au shell nanoparticles, which can protect 4MBA molecules from unwanted external environments and provide a high enhancement. The parameters affecting the detection sensitivity were discussed and optimized. The limit detection of florfenicol in milk can reach 0.1 µg/kg. To evaluate the performance of GERTs immunoassay, Ag@4MBA tags immunoassay was conducted and the results were compared. Moreover, Raman mapping was investigated to improve the quantitative prediction model with R2 of 0.981 achieved, by eliminating the signal fluctuations caused by the inhomogeneous distribution of GERTs.
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Ouro , Nanopartículas Metálicas , Animais , Ouro/química , Imunoensaio/métodos , Nanopartículas Metálicas/química , Leite , Análise Espectral Raman/métodos , Tianfenicol/análogos & derivadosRESUMO
Since microplastics (MPs) bring the potential risks to human health when plastics are ingested, more needs to be known about the presence and abundance of human ingestion of MPs. To address these issues, we reviewed 108 publications in Web of Science concerning abundances, sources, and analytical methods of MPs in human daily intake including fish, salt, drinking water, beverages, package food, and other food. The results demonstrate that aquatic food products (fish and bivalves) present a wide range of 0-10.5 items/g for bivalves and 0-20 items/individual for fish. Salt data in literatures present a concentration of 0-13,629 particles/kg. Drinking water is also a pathway of MPs exposure to human, presenting a concentration range from 0 to 61 particles/L for tap water and 0 to 6292 MPs/L for bottled water. Besides, MPs have been found in beverages, package food, sugar, honey, vegetables, and fruits. Therefore, human intake of MPs via ingestion is a nonnegligible exposure route.
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Bebidas/análise , Contaminação de Alimentos/análise , Microplásticos/efeitos adversos , Plásticos/efeitos adversos , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Humanos , Microplásticos/análise , Plásticos/análiseRESUMO
Microplastics (MPs) have been proven to concentrate hydrophobic organic contaminants (HOCs) from seawater as the sorbent phase, and the concentration of HOCs in aqueous solutions could be estimated from MPs preloaded with HOCs by equilibrium partition coefficient. This study firstly proposed to in situ quantify fluoranthene (a representative HOCs) pre-concentrated on MPs using surface enhance raman scattering (SERS) in combination with mathematical models, as an efficient monitoring tool for fluoranthene pollution in the aquatic environment. AgNPs-coated quartz (AgNPs@SiO2) substrate was fabricated. The SERS substrate was tested using fluoranthene standard solution with the minimal detectable concentration of 1 ng/mL achieved. Applying SERS for the detection of fluoranthene sorbed on MPs, the detection limit of fluoranthene on MPs was 3.3 ng/g, where the concentration in the corresponding equilibrium seawater was 0.97 ng/mL. Since more than one fluoranthene peak was observed, the quantitative detection was investigated by interval partial least square model. Eight characteristic peak ranges were selected to develop the model for predicting fluoranthene concentration, with R2c and R2v of 0.90 and 0.82, respectively. The study provides a promising solution to monitor trace level of contaminations in aquatic environment, using MPs as the passive sampler.
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The role of plastic as a vector for bioaccumulation of hydrophobic organic pollutants has been widely studied. However, the interactions between microplastics (MPs) and crude oil, and the transfer kinetics of sorbed oil from ingested MPs into aquatic biota are largely unknown. In this study, interactions between MPs and crude oil in seawater and digestive tract mimic of aquatic biota have been examined. To mimic the living, transportation and cooking conditions of aquatic organisms, sorption and desorption behaviors were investigated under room temperature-bath (25 °C), ice-bath (0â¼4 °C) and boiling water-bath (95â¼100 °C), and pH was set as 4 and 7 for the simulated gut fluid. The results showed that sorption capacity of polyethylene (PE) MPs for crude oil in seawater was higher than that in intestinal tract, indicating more oil residue in aqueous phase of gut fluid in the present of organic particles. The sorption kinetics models were well fitted to the pseudo-order model, and isotherms models were well fitted to the Freundlich model. In addition, the results demonstrated that temperature played a significant effect on crude oil viscosity, and the sorption capacity under different temperatures was in the order of 25 °C > 95â¼100 °C > 0â¼4 °C, indicating that more oil was remained in aqueous phase at boiling water-bath and ice-bath. The increment of pH enhances the sorption capacities of PE MPs. Moreover, the desorption experiment has supplemented the current findings from the sorption experiments.
Assuntos
Microplásticos/química , Petróleo , Polietileno/química , Poluentes Químicos da Água/química , Adsorção , Organismos Aquáticos , Interações Hidrofóbicas e Hidrofílicas , Cinética , Plásticos/química , Água do Mar/química , Poluentes Químicos da Água/análiseRESUMO
Microplastics (MPs) in aquatic organisms are raising increasing concerns regarding their potential damage to ecosystems. To date, Raman and Fourier transform infrared spectroscopy techniques have been widely used for detection of MPs in aquatic organisms, which requires complex protocols of tissue digestion and MP separation and are time- and reagent-consuming. This novel approach directly separates, identifies, and characterizes MPs from the hyperspectral image (HSI) of the intestinal tract content in combination with a support vector machine classification model, instead of using the real digestion/separation protocols. The procedures of HSI acquisition (1 min) and data analysis (5 min) can be completed within 6 min plus the sample preparation and drying time (30 min) where necessary. This method achieved a promising efficiency (recall >98.80%, precision >96.22%) for identifying five types of MPs (particles >0.2 mm). Moreover, the method was also demonstrated to be effective on field fish from three marine fish species, revealing satisfying detection accuracy (particles >0.2 mm) comparable to Raman analysis. The present technique omits the digestion protocol (reagent free), thereby significantly reducing reagent consumption, saving time, and providing a rapid and efficient method for MP analysis.