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1.
Angew Chem Int Ed Engl ; : e202407870, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748475

RESUMO

Converting spent lithium-ion batteries (LIBs) cathode materials into environmental catalysts has drawn more and more attention. Herein, we fabricated a Co3O4-based catalyst from spent LiCoO2 LIBs (Co3O4-LIBs) and found that the role of Al and Cu from current collectors on its performance is nonnegligible. The density functional theory calculations confirmed that the doping of Al and/or Cu upshifts the d-band center of Co. A Fenton-like reaction based on peroxymonosulfate (PMS) activation was adopted to evaluate its activity. Interestingly, Al doping strengthened chemisorption for PMS (from -2.615 eV to -2.623 eV) and shortened Co-O bond length (from 2.540 Å to 2.344 Å) between them, whereas Cu doping reduced interfacial charge-transfer resistance (from 28.347 kΩ to 6.689 kΩ) excepting for the enhancement of the above characteristics. As expected, the degradation activity toward bisphenol A of Co3O4-LIBs (0.523 min-1) was superior to that of Co3O4 prepared from commercial CoC2O4 (0.287 min-1). Simultaneously, the reasons for improved activity were further verified by comparing activity with catalysts doped Al and/or Cu into Co3O4. This work reveals the role of elements from current collectors on the performance of functional materials from spent LIBs, which is beneficial to the sustainable utilization of spent LIBs.

2.
J Hazard Mater ; 470: 134215, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38626678

RESUMO

Selective and efficient removal of thiosulfates (S2O32-) to recover high-purity and value-added thiocyanate products by fractional crystallization process is a promising route for the resource treatment of coke oven gas desulfurization wastewater. Herein, catalytic wet air oxidation (CWAO), with manganese-based oxide synthesized from spent ternary lithium-ion batteries (MnOx-LIBs), was proposed to selectively remove S2O32- from desulfurization wastewater. 98.0 % of S2O32- is selectively removed by the MnOx-LIBs CWAO system, which was 4.1 times that of the MnOx CWAO system. The synergistic effect among multiple metals from spent LIBs induces the enlarged specific surface area, increased reactive sites and formation of oxygen vacancy, promoting the adsorption and activation of O2, thereby realizing high-efficiency removal of S2O32-. The satisfactory selective removal efficiency can be maintained in the proposed system under complex environmental conditions. Notably, the proposed system is cost-effective and applicable to actual wastewater, in which 81.2 % of S2O32- is selectively removed from coke oven gas desulfurization wastewater. More importantly, compared with the typical processes, the proposed process is simpler and more environmentally-friendly. This work provides an alternative route to selectively remove S2O32- from coke oven gas desulfurization wastewater, expecting to drive the development of resource utilization of coke oven gas desulfurization wastewater.

3.
Chemosphere ; 357: 142063, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38636912

RESUMO

Rapid and sensitive analysis of bisphenol A (BPA) is essential for preventing health risks to humans and animals. Hence, a signal-amplified electrochemical aptasensor without repetitive polishing and modification of working electrode was developed for BPA using Au-decorated magnetic reduced graphene oxide (Au/MrGO)-based recognition probe (RP) and DNA nanospheres (DNS)-based signal probe (SP) cooperative signal amplification. The DNS served as a signal molecule carrier and signal amplifier, while Au/MrGO acted as a signal amplifier and excellent medium for magnetic adsorption and separation. Moreover, utilizing the excellent magnetic properties of Au/MrGO eliminates the need for repetitive polishing and multi-step direct modification of the working electrode while ensuring that all detection processes take place in solution and that used Au/MrGO can be easily recycled. The proposed aptasensor exhibited not only good stability and selectivity, but also excellent sensitivity with a limit of detection (LOD) of 8.13 fg/mL (S/N = 3). The aptasensor's practicality was proven by spiking recovery tests on actual water samples and comparing the results with those detected by HPLC. The excellent sensitivity and selectivity make this aptasensor an alternative and promising avenue for rapid detection of BPA in environmental monitoring.


Assuntos
Aptâmeros de Nucleotídeos , Compostos Benzidrílicos , Técnicas Biossensoriais , Técnicas Eletroquímicas , Eletrodos , Ouro , Grafite , Limite de Detecção , Nanosferas , Fenóis , Grafite/química , Compostos Benzidrílicos/análise , Compostos Benzidrílicos/química , Fenóis/análise , Fenóis/química , Ouro/química , Nanosferas/química , Técnicas Eletroquímicas/métodos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Poluentes Químicos da Água/análise , DNA/química
4.
Chemosphere ; 350: 141004, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-38141682

RESUMO

Polychlorinated naphthalenes (PCNs) were characterized as persistent organic pollutants (POPs) that were widely distributed in the environment. Although the striking in vivo toxicity of these pollutants towards both animals and humans was well documented, their cytotoxicity and mechanism of action have not been extensively investigated. In this study, the in vitro antiproliferative activity of mono- and di-chloronaphthalenes as representative PCNs were evaluated and the results indicated strong growth inhibitory effects against mammalian cells, especially the human breast MCF-10A cell and human hepatic HL-7702 cells. 2-Chloronaphthalene with the most potent antiproliferative effects within the tested PCNs, which showed IC50 values ranging from 0.3 mM to 1.5 mM against selected human cell lines, was investigated for its working mechanisms. It promoted cellular apoptosis of MCF-10A cells upon the concentration of 200 µM. It also induced the autophagy of MCF-10A cells in a dose-dependent manner, resulting in cell death via the interaction of autophagy and apoptosis. Thus, these findings supported the theoretical foundation for interventional treatment of PCNs toxicity and also provided implications for the use of chemopreventive agents against the toxic chlorinated naphthalenes in the environments.


Assuntos
Poluentes Ambientais , Animais , Humanos , Poluentes Ambientais/análise , Fígado/química , Naftalenos/toxicidade , Naftalenos/análise , Apoptose , Mamíferos
5.
Transl Cancer Res ; 12(10): 2764-2780, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37969389

RESUMO

Background: In recent years, with the development of transcriptome sequencing, the molecular characteristics of tumors are gradually revealed. Because of the complexity of tumor transcriptome, there is a need to look for the molecular signatures which can be used to evaluate the tissue origin and cell stemness of tumors in order to promote the diagnosis and treatment of tumors. Methods: Tumor tissue-specific gene sets (TTSGs) consisting of 200 genes were selected using RNA expression data of 9,875 patients from 33 tumor types. t-distributed Stochastic Neighbor Embedding (t-SNE) was used for dimensionality reduction and visualization of TTSGs in each tumor type. To evaluate oncogenic dedifferentiation and loss of cell stemness, Euclidean distance from each sample to a human embryo single-cell RNA-seq dataset (GSE36552) of TTSGs was calculated as TTSGs index indicating dissimilarity of tumors and embryo. TTSGs index was evaluated for prognosis in each tumor type. Two published signature indexes, the mRNA signature index (mRNAsi) and CIBERSORT, were compared to assess the correlation between the TTSGs index with cell stemness and immune microenvironment. Finally, the difference of prognosis, immune microenvironment and radiotherapy outcomes were compared between patients with high and low TTSGs index. Results: In this study, all 33 tumor types in The Cancer Genome Atlas (TCGA) were embedded into isolated clusters by t-SNE and confirmed by k-nearest neighbors (kNN) algorithm. Clusters of squamous-cell carcinoma were adjacent to each other revealing similar histologic origin. Basal-like breast cancer was separated from luminal and HER-2-amplified subtypes and closed to squamous-cell carcinoma. TTSGs index was related to overall survival outcomes in cancers derived from liver, thyroid, brain, cervical and kidney. There was a positive correlation between mRNAsi and TTSGs index in pan-kidney and pan-neuronal cancers. Furthermore, cell fractions of M2 macrophages and total leukocytes increased in the group with higher TTSGs index. Patients with higher TTSGs index had longer overall survival time and less radiation therapy resistance compared to patients with lower TTSGs index. Conclusions: The signature of TTSGs is related to tumor expression features that distinguish tumors of different histologic origin using t-SNE. The signature also relates to prognosis of certain kinds of tumors.

6.
Environ Sci Technol ; 57(36): 13579-13587, 2023 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-37653710

RESUMO

The traditional hydrolysis-cooling-adsorption process for coke oven gas (COG) desulfurization urgently needs to be improved because of its complex nature and high energy consumption. One promising alternative for replacing the last two steps is selective catalytic oxidation. However, most catalysts used in selective catalytic oxidation require a high temperature to achieve effective desulfurization. Herein, a robust 30Fe-MCM41 catalyst is developed for direct desulfurization at medium temperatures after hydrolysis. This catalyst exhibits excellent stability for over 300 h and a high breakthrough sulfur capacity (2327.6 mgS gcat-1). Introducing Ag into the 30Fe-MCM41 (30Fe5Ag-MCM41) catalyst further enhances the H2S removal efficiency and sulfur selectivity at 120 °C. Its outstanding performance can be attributed to the synergistic effect of Fe-Ag clusters. During H2S selective oxidation, Fe serves as the active site for H2S adsorption and dissociation, while Ag functions as the catalyst promoter, increasing Fe dispersion, reducing the oxidation capacity of the catalyst, improving the desorption capacity of sulfur, and facilitating the reaction between active oxygen species and [HS]. This process provides a potential route for enhancing COG desulfurization.


Assuntos
Coque , Sulfeto de Hidrogênio , Adsorção , Hidrogênio , Sulfetos , Temperatura
7.
Chemosphere ; 339: 139708, 2023 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-37536533

RESUMO

Triclosan (TCS), a broad-spectrum antibacterial chemical, has been extensively used in personal daily care items, household commodities, and clinical medications; therefore, humans are at risk of being exposed to TCS in their daily lives. This chemical also accumulated in food chains, and potential risks were associated with its metabolism in vivo. The aim of this study was to investigate the difference in metabolic profile of TCS by hepatic P450 enzymes and extrahepatic P450s, and also identify chemical structures of its metabolites. The results showed that RLM mediated the hydroxylation and cleavage of the ether moiety of TCS, resulting in phenolic metabolites that are more polar than the parent compound, including 4-chlorocatechol, 2,4-dichlorophenol and monohydroxylated triclosan. The major metabolite of CYP1A1 and CYP1B1 mediated TCS metabolism is 4-chlorochol. We also performed molecular docking experiments to investigate possible binding modes of TCS in the active sites of human CYP1B1, CYP1A1, and CYP3A4. In addition to in vitro experiments, we further examined the cytotoxic effects of TCS on HepG2 cells expressing hepatic P450 and MCF-7/1B1 cells expressing CYP1B1. It exhibited significant cytotoxicity on HepG2, MCF-10A and MCF-7/1B1 cells, with IC50 values of 70 ± 10 µM, 20 ± 10 µM and 60 ± 20 µM, respectively. The co-incubation of TCS with glutathione (GSH) as a chemopreventive agent could reduce the cytotoxicity of TCS in vitro. The chemopreventive effects of GSH might be ascribed to the promotion of TCS efflux mediated by membrane transporter MRP1 and also its antioxidant property, which partially neutralized the oxidative stress of TCS on mammalian cells. This study contributed to our understanding of the relationship between the P450 metabolism and the toxicity of TCS. It also had implications for the use of specific chemopreventive agents against the toxicity of TCS.


Assuntos
Triclosan , Animais , Humanos , Triclosan/toxicidade , Triclosan/metabolismo , Citocromo P-450 CYP1A1/metabolismo , Simulação de Acoplamento Molecular , Sistema Enzimático do Citocromo P-450/metabolismo , Fenóis , Quimioprevenção , Mamíferos/metabolismo
8.
Artigo em Inglês | MEDLINE | ID: mdl-37410647

RESUMO

In this article, we bring forward a completely perturbed nonconvex Schatten p -minimization to address a model of completely perturbed low-rank matrix recovery (LRMR). This article based on the restricted isometry property (RIP) and the Schatten- p null space property (NSP) generalizes the investigation to a complete perturbation model thinking over not only noise but also perturbation, and it gives the RIP condition and the Schatten- p NSP assumption that guarantee the recovery of low-rank matrix and the corresponding reconstruction error bounds. In particular, the analysis of the result reveals that in the case that p decreases 0 and for the complete perturbation and low-rank matrix, the condition is the optimal sufficient condition (Recht et al., 2010). In addition, we study the connection between RIP and Schatten- p NSP and discern that Schatten- p NSP can be inferred from the RIP. The numerical experiments are conducted to show better performance and provide outperformance of the nonconvex Schatten p -minimization method comparing with the convex nuclear norm minimization approach in the completely perturbed scenario.

9.
J Med Chem ; 66(12): 8011-8029, 2023 06 22.
Artigo em Inglês | MEDLINE | ID: mdl-37272653

RESUMO

Bombesin receptor subtype-3 (BB3, BRS-3) is an orphan Gαq protein-coupled receptor. The characterization of novel synthetic ligands for BB3 is an alternative and attractive strategy to study its diverse physiological functions. Here, we uncovered the intimate pairing of DMAKO-00 and its derivatives with BB3. Dimethyl shikonin oxime 5a (DSO-5a) was identified as the most potent agonist for BB3 (pEC50 = 8.422 in IP-1 accumulation), which was 898-fold more potent than DMAKO-00. Importantly, without brain penetration, DSO-5a improved glucose tolerance in C57BL/6 mice through BB3 and ameliorated glucose homeostasis in diabetic db/db mice. We further revealed that DSO-5a upregulated PPAR-gamma activity via BB3 through a quantitative proteomics approach. Collectively, our study demonstrated that DSO-5a, a representative compound of DMAKO-00 derivatives, is a potent, selective, and low-brain-penetrating agonist for BB3, and BB3 is a promising treatment target for type 2 diabetes mellitus.


Assuntos
Diabetes Mellitus Tipo 2 , Receptores da Bombesina , Camundongos , Animais , Diabetes Mellitus Tipo 2/tratamento farmacológico , Camundongos Endogâmicos C57BL , Glucose , Bombesina
10.
J Environ Manage ; 342: 118178, 2023 Sep 15.
Artigo em Inglês | MEDLINE | ID: mdl-37196612

RESUMO

There has been growing concern among the public over the environmental impacts of the copper (Cu) mining and mineral processing industries. As an effective tool enabling interactions of all energy and material flows with the environment, Life Cycle Assessment (LCA) is used in many countries to identify environmental hotspots associated with operations, based on which improvements can be made. However, robust LCA research in this sector is lacking in China. This study aimed to fill this critical gap by investigating two typical Cu mining and mineral processing operations using different mining technologies, based on globally harmonized LCA methodologies. The results of the overall environmental impacts were obtained using a sensitivity analysis. Electricity (38%-74%), diesel (8%-24%) and explosives (4%-22%) were identified as the three main controlling factors. At the same time, the mineral processing stage was found to be the major production stage (60%-79%), followed by the mining stage (17%-39%) and the wastewater treatment (1%-13%). Global Warming Potential (GWP) was prioritized as the most important environmental issue (59%) across the selected impact categories. In addition, it was initially found that underground mining technology has better environmental performance than open-pit technology. Finally, the potential for improvement was estimated and discussed for the three identified controlling factors. Using GWP as an example, using green electricity can effectively reduce CO2 emissions by 47%-67%, whereas replacing diesel and explosives with cleaner fuels and explosives may contribute to lower CO2 emissions by 6% and 9%, respectively.


Assuntos
Cobre , Substâncias Explosivas , Dióxido de Carbono , Meio Ambiente , Mineração , Minerais
11.
J Matern Fetal Neonatal Med ; 36(1): 2192853, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36966813

RESUMO

OBJECTIVE: To explore the association between inter-pregnancy intervals and placenta previa and placenta accreta spectrum among women who had prior cesarean deliveries with respect to maternal age at first cesarean delivery. METHODS: This retrospective study included clinical data from 9981 singleton pregnant women with a history of cesarean delivery at 11 public tertiary hospitals in seven provinces of China between January 2017 and December 2017. The study population was divided into four groups (<2, 2-5, 5-10, ≥10 years of the interval) according to the inter-pregnancy interval. The rate of placenta previa and placenta accreta spectrum among the four groups was compared, and multivariate logistic regression was used to analyze the relationship between inter-pregnancy interval and placenta previa and placenta accreta spectrum with respect to maternal age at first cesarean delivery. RESULTS: Compared to women aged 30-34 years old at first cesarean delivery, the risk of placenta previa (aRR, 1.48; 95% CI, 1.16-1.88) and placenta accreta spectrum (aRR, 1.74; 95% CI, 1.28-2.35) were higher among women aged 18-24. Multivariate regression results showed that women at 18-24 with <2 years intervals exhibited a 5.05-fold increased risk for placenta previa compared with those with 2-5-year intervals (aRR, 5.05; 95% CI, 1.13-22.51). In addition, women aged 18-24 with less than 2 years intervals had an 8.44 times greater risk of developing PAS than women aged 30-34 with 2 to 5 years intervals (aRR, 8.44; 95% CI, 1.82-39.26). CONCLUSIONS: The findings of this study suggested that short inter-pregnancy intervals were associated with increased risks for placenta previa, and placenta accreta spectrum for women under 25 years at first cesarean delivery, which may be partly attributed to obstetrical outcomes.


Assuntos
Placenta Acreta , Placenta Prévia , Gravidez , Feminino , Humanos , Adulto , Idade Materna , Placenta Prévia/epidemiologia , Estudos Retrospectivos , Placenta Acreta/epidemiologia , Placenta Acreta/etiologia , Intervalo entre Nascimentos , Fatores de Risco
12.
Front Environ Sci Eng ; 17(8): 95, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36844109

RESUMO

Recent years have witnessed significant improvement in China's air quality. Strict environmental protection measures have led to significant decreases in sulfur dioxide (SO2), nitrogen oxides (NO x ), and particulate matter (PM) emissions since 2013. But there is no denying that the air quality in 135 cities is inferior to reaching the Ambient Air Quality Standards (GB 3095-2012) in 2020. In terms of temporal, geographic, and historical aspects, we have analyzed the potential connections between China's air quality and the iron and steel industry. The non-target volatile organic compounds (VOCs) emissions from iron and steel industry, especially from the iron ore sinter process, may be an underappreciated index imposing a negative effect on the surrounding areas of China. Therefore, we appeal the authorities to pay more attention on VOCs emission from the iron and steel industry and establish new environmental standards. And different iron steel flue gas pollutants will be eliminated concurrently with the promotion and application of new technology.

13.
Water Res ; 232: 119685, 2023 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-36739661

RESUMO

Ubiquitous macromolecular natural organic matter (NOM) in wastewater seriously influences the removal of emerging small-molecule contaminants via heterogeneous advanced oxidation processes because this material covers active sites and quenches reactive oxygen species. Here, sponge-like magnetic manganese ferrite (MnFe2O4-S) with a three-dimensional hierarchical porous structure was prepared via a facile solvent-free molten method. Compared with the particle-like structure of MnFe2O4-P, the sponge-like structure of MnFe2O4-S presents an enlarged specific surface area (112.14 m2·g-1 vs. 58.73 m2·g-1) and a smaller macropore diameter (68.2-77.2 nm vs. 946.5 nm). Enlarging the specific surface area increases the exposure of active sites, and adjusting the pore size helps sieve NOM and emerging contaminants. These changes are expected to effectively improve the degradation activity and overcome interference. To confirm the superiority of the sponge-like structure, MnFe2O4-S was used to activate peroxymonosulfate (PMS) for the degradation of multiple emerging contaminants, and its ability to degrade bisphenol A with and without humic acid (HA) was compared with that of MnFe2O4-P. The degradation activity of MnFe2O4-S was 1.6 times greater than that of MnFe2O4-P. Moreover, 20 mg·L-1 HA inhibited the degradation activity of MnFe2O4-S by only 7.1%, which was much lower than that obtained for MnFe2O4-P (53.4%). In addition, the excellent performance was maintained in multiple water matrices. Notably, under lake water matrices, the degradation activity of MnFe2O4-P was inhibited by 35.6% while that of MnFe2O4-S was hardly inhibited. More importantly, the MnFe2O4-S/PMS system was also applicable to the treatment of actual wastewater and 73.0% and 90.1% of total organic carbon and chemical oxygen demand was removed from bio-treated coking wastewater containing non-biodegradable contaminants and NOM. This study provides an alternative route for the green production of high-activity porous spinel ferrites with environmental anti-interference properties.


Assuntos
Águas Residuárias , Água , Solventes , Porosidade
14.
Chemosphere ; 310: 136929, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36273607

RESUMO

The separation of hardness ions such as calcium and magnesium from hard water can improve water quality, which is important but technically challenging. Nanofiltration (NF) has attracted much attention because of its efficiency, environmental friendliness and low cost. However, common NF membranes with a singly (either positively or negatively) charged layer have insufficient water softening capacity. In this work, two types of dual-layer Janus charged polyamide NF membranes composed of oppositely charged inner and outer layers were developed for the first time by sequential electrospray polymerization strategy for efficient water softening. The effect of the microstructure of the dually charged barrier layer on the separation performance of divalent salt ions was explored. Detailed mechanistic studies revealed that the microstructure of the outer layer of the barrier layer played a crucial role in the ion separation of the Janus membrane due to its control of the reverse transport of ions. Janus charged polyamide NF membrane with a loose outer layer exhibited better water softening performance (93.6% of hardness removed) compared to the singly charged NF membranes due to the simultaneous dual electrostatic effect and no ion reverse transport confinement. This Janus charged NF membrane also possessed good antifouling performance, mainly due to its negatively charged outer layers. The mechanistic insights gained in this study reveal the huge potential of microstructural design toward high-performance Janus charged NF membranes, and provide important guidance on the future development of high-efficiency water softening NF membranes.


Assuntos
Membranas Artificiais , Nylons , Nylons/química , Polimerização , Abrandamento da Água , Íons
15.
Front Environ Sci Eng ; 17(3): 31, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36313056

RESUMO

The diverse and large-scale application of disinfectants posed potential health risks and caused ecological damage during the 2019-nCoV pandemic, thereby increasing the demands for the development of disinfectants based on natural products, with low health risks and low aquatic toxicity. In the present study, a few natural naphthoquinones and their derivatives bearing the 1,4-naphthoquinone skeleton were synthesized, and their antibacterial activity against selected bacterial strains was evaluated. In vitro antibacterial activities of the compounds were investigated against Escherichia coli and Staphylococcus aureus. Under the minimum inhibitory concentration (MIC) of ⩽ 0.125 µmol/L for juglone (1a), 5,8-dimethoxy-1,4-naphthoquinone (1f), and 7-methyl-5-acetoxy-1,4-naphthoquinone (3c), a strong antibacterial activity against S. aureus was observed. All 1,4-naphthoquinone derivatives exhibited a strong antibacterial activity, with MIC values ranging between 15.625 and 500 µmol/L and EC50 values ranging between 10.56 and 248.42 µmol/L. Most of the synthesized compounds exhibited strong antibacterial activities against S. aureus. Among these compounds, juglone (1a) showed the strongest antibacterial activity. The results from mechanistic investigations indicated that juglone, a natural naphthoquinone, caused cell death by inducing reactive oxygen species production in bacterial cells, leading to DNA damage. In addition, juglone could reduce the self-repair ability of bacterial DNA by inhibiting RecA expression. In addition to having a potent antibacterial activity, juglone exhibited low cytotoxicity in cell-based investigations. In conclusion, juglone is a strong antibacterial agent with low toxicity, indicating that its application as a bactericidal agent may be associated with low health risks and aquatic toxicity. Electronic Supplementary Material: Supplementary material is available in the online version of this article at 10.1007/s11783-023-1631-2 and is accessible for authorized users.

16.
Chemosphere ; 311(Pt 2): 137154, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36351468

RESUMO

Bisphenol A (BPA) is a harmful endocrine disruptor, sensitive and rapid quantification of BPA is highly desirable. In this work, a novel synergistic signal-amplifying electrochemical biosensor was developed for BPA detection by using a recognition probe (RP) constructed by BPA aptamer modified gold nanoparticles-loaded magnetic reduced graphene oxide (Aptamer-MrGO@AuNPs), and a signal probe (SP) constructed by BPA aptamer-complementary single-stranded DNA (ssDNA) functionalized methylene blue (MB)-loaded gold nanoparticle (ssDNA-AuNP@MBs). The RP and SP can self-assemble to form a stable RP-SP complex through complementary base pairing. The current intensity of the biosensor correlates with the number of RP-SP complexes. In the presence of BPA, the BPA aptamer can capture BPA with high selectivity and affinity, form an RP-BPA complex and dissociate the RP-SP complex to release SP, resulting in a decrease in the current signal intensity of the biosensor. A single AuNP could be loaded with multiple BPA aptamers and MBs, which improves the recognition efficiency and enhances the signal intensity. Due to the magnetic properties of MrGO@AuNPs, the magnetic separation and adsorption of RP or RP-SP complex is very convenient, enabling all reaction processes to be carried out in solution, which not only improves the mass transfer efficiency, but also simplifies the operation. Under optimal conditions, the developed biosensor had a detection limit as low as 0.141 pg/mL and had been successfully applied to the detection of real environmental water samples. Therefore, the synergistic signal amplification strategy of RP and SP has potential value in the detection of trace pollutants in the water environment.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Biossensoriais , Nanopartículas Metálicas , Ouro/química , DNA de Cadeia Simples , Aptâmeros de Nucleotídeos/química , Nanopartículas Metálicas/química , Técnicas Biossensoriais/métodos , DNA Complementar , Água , Técnicas Eletroquímicas/métodos , Limite de Detecção
17.
J Environ Manage ; 324: 116405, 2022 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-36352730

RESUMO

The mass transfer on the catalyst surface has a great influence on the selectivity of electrocatalytic nitrate reduction to nitrogen. In this study, a Pd-Cu adsorption confined nickel foam cathode is designed in the absence of both proton exchange membranes and chloride ions. The repulsion of the cathode enables intermediate products such as nitrite to accumulate in the confined region, resulting in an increase in the possibility of a second-order reaction to form nitrogen. The system can obtain more than 92% continuous N2 selectivity when it is used to treat 200 mg L-1 NO3--N under a current density of 8 mA cm-2, which is not only higher than those of semiconfined and nonconfined systems but also significantly better than the results obtained by Pd-Cu directly modified cathodes prepared by electrodeposition or impregnation. It is found that a high initial nitrate concentration and low current density are more beneficial for the accumulation of intermediates on Pd-Cu catalysts, thus improving the formation of nitrogen. A mechanism study reveals that the intermediates can completely occupy the active sites on the surface of Pd, avoiding the generation of active hydrogen, and therefore inhibiting the first-order reaction to produce ammonia. Moreover, the reducibility of Pd-Cu can also be gradually improved under the function of the cathode so that the system exhibits good stability. This study demonstrates an environmentally friendly and promising method for total nitrogen removal from industrial wastewater with high conductivity.

18.
Virus Res ; 321: 198915, 2022 11.
Artigo em Inglês | MEDLINE | ID: mdl-36084746

RESUMO

The key structure of the interface between the spike protein of Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) and human angiotensin-converting enzyme 2 (hACE2) acts as an essential switch for cell entry by the virus and drugs targets. However, this is largely unknown. Here, we tested three peptides of spike receptor binding domain (RBD) and found that peptide 391-465 aa is the major hACE2-interacting sites in SARS-CoV-2 spike RBD. We then identified essential amino acid residues (403R, 449Y, 454R) of peptide 391-465 aa that were critical for the interaction between the RBD and hACE2. Additionally, a pseudotyped virus containing SARS-CoV-2 spike with individual mutation (R454G, Y449F, R403G, N439I, or N440I) was determined to have very low infectivity compared with the pseudotyped virus containing the wildtype (WT) spike from reference strain Wuhan 1, respectively. Furthermore, we showed the key amino acids had the potential to drug screening. For example, molecular docking (Docking) and infection assay showed that Cephalosporin derivatives can bind with the key amino acids to efficiently block infection of the pseudoviruses with wild type spike or new variants. Moreover, Cefixime inhibited live SARS-CoV-2 infection. These results also provide a novel model for drug screening and support further clinical evaluation and development of Cephalosporin derivatives as novel, safe, and cost-effective drugs for prevention/treatment of SARS-CoV-2.


Assuntos
Enzima de Conversão de Angiotensina 2 , Tratamento Farmacológico da COVID-19 , Aminoácidos/metabolismo , Aminoácidos Essenciais/metabolismo , Antivirais/química , Antivirais/farmacologia , Sítios de Ligação , Cefixima , Humanos , Simulação de Acoplamento Molecular , Peptídeos/metabolismo , Peptidil Dipeptidase A/metabolismo , Ligação Proteica , SARS-CoV-2 , Glicoproteína da Espícula de Coronavírus/química
19.
Environ Res ; 215(Pt 2): 114299, 2022 12.
Artigo em Inglês | MEDLINE | ID: mdl-36096167

RESUMO

The proper disposals of spent lithium-ion batteries (LIBs) and volatile organic compounds (VOCs) both have a significant impact on the environment and human health. In this work, different morphologies of α-MnO2 catalysts are synthesized using a manganese-based compound as the precursor which is high-selectively recovered from spent lithium-ion ternary batteries. Different synthesis methods including the co-precipitation method, hydrothermal method, and impregnation method are used to prepare different morphologies of α-MnO2 catalysts and their catalytic activities of toluene oxidation are investigated. Experimental results show that MnO2-HM-140 with stacked nanorods synthesized using the hydrothermal method exhibits the best catalytic performance of toluene oxidation (T90 of 226 °C under the WHSV of 60,000 mL g-1·h-1), which could be attributed to its better redox ability at low temperature and much more abundant adsorbed oxygen species at low temperature. The adsorption abilities of toluene and the replenish rate of surface lattice oxygen can be enhanced due to the increase of oxygen vacancies on the surface of MnO2-HM-140. Furthermore, the results of in-situ DRIFTS and TD/GC-MS imply that benzoate species are the main intermediate groups and then the reaction pathway of toluene oxidation on the surface of MnO2-HM-140 is proposed.


Assuntos
Compostos de Manganês , Compostos Orgânicos Voláteis , Benzoatos , Humanos , Lítio , Manganês , Óxidos , Oxigênio , Tolueno
20.
J Environ Manage ; 321: 115982, 2022 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-36104886

RESUMO

Hydrodynamic cavitation has been a promising method and technology in wastewater treatment, while the principles based on the design of cavitational reactors to optimize cavitation yield and performance remains lacking. Computational fluid dynamics (CFD), a supplementation of experimental optimization, has become an essential tool for this issue, owing to the merits of low investment and operating costs. Nevertheless, researchers with a non-engineering background or few CFD fundamentals used straightforward numerical strategies to treat cavitating flows, and this might result in many misinterpretations and consequently poor computations. This review paper presents the rationale behind hydrodynamic cavitation and application of cavitation modeling specific to the reactors in wastewater treatment. In particular, the mathematical models of multiphase flow simulation, including turbulence closures and cavitation models, are comprehensively described, whilst the advantages and shortcomings of each model are also identified and discussed. Examples and methods of the coupling of CFD technology, with experimental observations to investigate into the hydrodynamic behavior of cavitating devices that feature linear and swirling flows, are also critically summarized. Modeling issues, which remain unaddressed, i.e., the implementation strategies of numerical models, and the definition of cavitation numbers are identified and discussed. Finally, the advantages of CFD modeling are discussed and the future of CFD applications in this research area is also outlined. It is expected that the present paper would provide decision-making support for CFD beginners to efficiently perform CFD modeling and promote the advancement of cavitation simulation of reactors in the field of wastewater treatment.


Assuntos
Hidrodinâmica , Purificação da Água , Simulação por Computador , Modelos Teóricos , Tecnologia
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