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1.
Braz. j. biol ; 84: e256905, 2024. tab
Artigo em Inglês | LILACS, VETINDEX | ID: biblio-1360212

RESUMO

During present study, the copper (Cu) mediated oxidative stress was measured that induced DNA damage by concentrating in the tissues of fish, Catla catla (14.45±1.24g; 84.68±1.45mm) (Hamilton,1822). Fish fingerlings were retained in 5 groups for 14, 28, 42, 56, 70 and 84 days of the exposure period. They were treated with 2/3, 1/3, 1/4 and 1/5 (T1-T4) of 96h lethal concentration of copper. Controls were run along with all the treatments for the same durations. A significant (p < 0.05) dose and time dependent concentration of Cu was observed in the gills, liver, kidney, muscles, and brain of C. catla. Among organs, the liver showed a significantly higher concentration of Cu followed by gills, kidney, brain, and muscles. Copper accumulation in these organs caused a significant variation in the activities of enzymes viz. superoxide dismutase (SOD), catalase (CAT) and peroxidase (POD). The SOD activity varied significantly in response to the exposure time of Cu as 56 > 70 > 42 > 84 > 28 > 14 days while CAT activity exhibited an inverse relationship with the increase in Cu concentration. POD activity showed a significant rise with an increase in Cu exposure duration. Comet assay exhibited significant DNA damage in the peripheral erythrocytes of Cu exposed C. catla. Among four exposure concentrations, 2/3rd of LC50 (T1) caused significantly higher damage to the nuclei compared to control. Increased POD and SOD activity, as well as a decrease in CAT activity in response to Cu, demonstrates the involvement of a protective mechanism against reactive oxygen species (ROS), whereas increased ROS resulted in higher DNA damage. These above-mentioned molecular markers can be efficiently used for the biomonitoring of aquatic environments and conservation of edible fish fauna.


Durante o presente estudo, o estresse oxidativo mediado pelo cobre (Cu) foi medido que induziu danos ao DNA por concentração nos tecidos de peixes, Catla catla (14,45 ± 1,24g; 84,68 ± 1,45mm) (Hamilton, 1822). Os alevinos foram retidos em 5 grupos por 14, 28, 42, 56, 70 e 84 dias do período de exposição. Eles foram tratados com 2/3, 1/3, 1/4 e 1/5 (T1-T4) de 96h de concentração letal de cobre. Os controles foram executados junto com todos os tratamentos para as mesmas durações. Uma significativa (p <0,05) concentração dependente do tempo e da dose de Cu foi observada nas brânquias, fígado, rim, músculos e cérebro de C. catla. Entre os órgãos, o fígado apresentou uma concentração significativamente maior de cobre, seguido por guelras, rins, cérebro e músculos. O acúmulo de cobre nesses órgãos causou uma variação significativa nas atividades das enzimas viz. superóxido dismutase (SOD), catalase (CAT) e peroxidase (POD). A atividade de SOD variou significativamente em resposta ao tempo de exposição de Cu como 56> 70> 42> 84> 28> 14 dias, enquanto a atividade de CAT exibiu uma relação inversa com o aumento na concentração de Cu. A atividade POD mostrou um aumento significativo com um aumento na duração da exposição ao Cu. O ensaio do cometa exibiu dano significativo ao DNA induzido por Cu nos eritrócitos periféricos de C. catla. Entre as quatro concentrações de exposição, 2/3 do LC50 (T1) causou danos significativamente maiores aos núcleos em comparação com o controle. O aumento da atividade de POD e SOD, bem como uma diminuição na atividade de CAT em resposta ao Cu, demonstra o envolvimento de um mecanismo protetor contra espécies reativas de oxigênio (ROS), enquanto o aumento de ROS resultou em maior dano ao DNA. Esses marcadores moleculares mencionados acima podem ser usados ​​de forma eficiente para o biomonitoramento de ambientes aquáticos e conservação da ictiofauna comestível.


Assuntos
Animais , Cobre , Peixes , Água Doce , Bioacumulação
2.
Food Chem ; 398: 133882, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-35986996

RESUMO

Herein, based on an artificial clickase-catalyzed bio-conjugation strategy, we established a sensitive fluorescent clickase-linked immunosorbent assay (FCLISA) platform using an oligonucleotide-molecular beacon (Oligo-MB) hairpin structure as a fluorescence switch for detection of food allergenic protein. Firstly, a highly stable Cu(I)-containing nanocube was prepared for usage as an artificial clickase, which could catalyze the bio-conjugation of two short oligonucleotides (i.e., Oligo-A and Oligo-B labeled by a 5'-alkyne and a 3'-azide group, respectively) through clickase-catalyzed azide/alkyne cycloaddition reaction. Subsequently, the formed long-chain oligonucleotide (Oligo-A-B) could hybridize with Oligo-MB hairpin to open hairpin structure, leading to its fluorescence turn on. By using clickase as an alternative enzymatic label in conventional ELISAs, the established FCLISA showed high sensitivity and accuracy in detection of casein, achieving a limit of detection as low as 1.5 × 10-8 g/mL. Additionally, FCLISA has been challenged by detecting the casein in real samples, indicating a great potential in food safety assay.


Assuntos
Azidas , Química Click , Alcinos/química , Alérgenos , Azidas/química , Caseínas , Cobre/química , Imunoensaio , Oligonucleotídeos/química
3.
J Hazard Mater ; 443(Pt B): 130335, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36370478

RESUMO

Air quality modeling (AQM) is often used to investigate gaseous pollution around industrial zones. However, this methodology requires accurate emission inventories, unbiased AQM algorithms and realistic boundary conditions. We introduce a new methodology for source apportionment of industrial gaseous emissions, which is based on a fuzzy clustering of ambient concentrations, along with a standard AQM approach. First, by applying fuzzy clustering, ambient concentration is expressed as a sum of non-negative contributions - each corresponding to a specific spatiotemporal pattern (STP); we denote this method as FUSTA (FUzzy SpatioTemporal Apportionment). Second, AQM of the major industrial emissions in the study zone generates another set of STP. By comparing both STP sets, all major source contributions resolved by FUSTA are identified, so a source apportionment is achieved. The uncertainty in FUSTA results may be estimated by comparing results for different numbers of clusters. We have applied FUSTA in an industrial zone in central Chile, obtaining the contributions from major sources of ambient SO2: a thermal power plant complex and a copper smelter, and other contributions from local and regional sources (outside the AQM domain). The methodology also identifies SO2 episodes associated to emissions from the copper smelter.


Assuntos
Poluentes Atmosféricos , Poluição do Ar , Poluentes Atmosféricos/análise , Material Particulado/análise , Gases , Cobre , Poluição do Ar/análise
4.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 1): 122069, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36371877

RESUMO

A novel fluorescent probe L consisting of ß-Cyclodextrin (ß-CD) and thiosemicarbazide moieties was designed for copper ions detection. Apparent fluorescence quenching of probe L in Tris-HCl(pH = 7.4)solution was observed only in the presence of Cu2+, among other interfering ions. The present probe L was 1:1 complexed with Cu2+ and the detection limit of probe L was calculated to be 1.37 µM. The results demonstrate that the probe L may provide a convenient method for visual detection of Cu2+ in the environmental and biological systems.


Assuntos
Ciclodextrinas , Corantes Fluorescentes , Cobre , Espectrometria de Fluorescência/métodos , Íons , Água
5.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 1): 122088, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379157

RESUMO

A high-performance fluorescent probe 2,5-dimercapto-1,3,4-thiadiazole copper nanoparticles (DMTD-CuNPs) was synthesized by hydrothermal method based on monovalent copper (Cu(I)) and 2,5-dimercapto-1,3,4-thiadiazole (DMTD), and it can effectively detect cysteine (Cys) in plasma. Experiments show that DMTD can reduces band gap of Cu(I) in DMTD-CuNPs, promote charge transfer transition from DMTD to Cu(I) and significantly enhance fluorescence intensity of DMTD-CuNPs at 515 nm. The large Stokes shift of DMTD-CuNPs is 315 nm, which can reduce the self-quenching of probe fluorescence and improves detection accuracy of the probe. In the presence of Cys, fluorescence of DMTD-CuNPs at 515 nm is significantly quenched because Cys reacts with Cu(I) in DMTD-CuNPs through Cu-S bond to form reduced charge transfer, which can be successfully used for the detection of Cys. Linear range and detection limit for Cys detection are 25-65 µM and 50 nM, respectively. Furthermore, feasibility of detecting Cys in plasma using DMTD-CuNPs probe was evaluated by standard addition method, and the absolute recovery is 96-99%. Such a DMTD-CuNPs probe shows high sensitivity, good selectivity and low detection limit for Cys, which is expected to be used for the practical analysis of Cys in plasma.


Assuntos
Cisteína , Corantes Fluorescentes , Corantes Fluorescentes/química , Cisteína/análise , Cobre/análise , Espectrometria de Fluorescência/métodos , Limite de Detecção
6.
Spectrochim Acta A Mol Biomol Spectrosc ; 287(Pt 2): 122084, 2023 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-36379087

RESUMO

Nanozymes have potential applications in many fields, and a novel copper-containing nanozyme with highly dispersity and uniformity was self-assembled for efficient degradation of various organic dyes in this work. In the nanozyme, histidine was used to coordinate with copper ions, and hydrogen peroxide was prone to Fenton-like reaction to generate hydroxylated copper oxide intermediates. The nanozyme showed good peroxidase-like activity, and also had the ability to catalyze the degradation of various organic dyes efficiently with good storage and recycling ability. Furthermore, the degradation kinetics and mechanism of nanozyme had been further studied, and found that hydroxyl radical and singlet oxygen play vital roles in the catalytic degradation process. Meanwhile, this nanozyme can efficiently degrade two organic compounds at the same time, and this system is capable of dealing with complex practical application scenarios where wastewater contains a variety of organic pollutants.


Assuntos
Cobre , Peróxido de Hidrogênio , Histidina , Corantes , Águas Residuárias
7.
J Hazard Mater ; 444(Pt A): 130417, 2023 02 15.
Artigo em Inglês | MEDLINE | ID: mdl-36410249

RESUMO

Biomineralization as an alternative to traditional remediation measures has been widely applied to remediate copper (Cu)-contaminated sites due to its environmental-friendly nature. Immobilizing Cu is, however, a challenging task as it inevitably causes inactivation of ureolytic bacteria. In the present work, a series of test tube experiments were conducted to derive the relationships of Cu immobilization efficiency versus pH conditions. The Cu speciation transformation that is invisible in the test tube experiments was investigated via numerical simulations. Apart from that, the one-dimensional soil column tests, accompanied by the X-ray diffraction (XRD) and Raman spectroscopy analysis, mainly aimed not only to investigate the variations of Cu immobilization efficiency with the depth but to reveal the underlying mechanisms affecting the Cu immobilization efficiency. The results of the test tube experiments highlight the necessity of narrowing pH ranges to as close as 7 by introducing an appropriate bacterial inoculation proportion. The coordination adsorption of Cu, while performing the one-dimensional soil column tests, is encouraged by alkaline environments, which differs from the test tube experiments where Cu2+ is capsulized by carbonate precipitates to prevent their migration. The findings highlight the potential of applying the microbial-induced carbonate precipitation (MICP) technology to Cu-rich water bodies and Cu-contaminated sites remediation.


Assuntos
Cobre , Recuperação e Remediação Ambiental , Solo , Carbonatos , Biomineralização
8.
Chemosphere ; 312(Pt 2): 137311, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36410501

RESUMO

In this study, cubic spinel structured CuCo2O4 (Copper cobaltite) nanospheres were fabricated by thermal decomposition method. The visible light degradation of organic contaminant methyl orange (MO) was focused in this study using the synthesized pure CuO, Co3O4 and CuCo2O4 with different weight ratios of raw materials (90:10, 75:25 and 50:50). It could be well realized that after the characterization techniques, the synthesized CuCo2O4 materials resembled cubic spinel structure as confirmed by X-ray diffraction (XRD) investigation. Meanwhile, all the synthesized materials through transmission electron microscopy (TEM) have showed cubic shaped particles and among the CuCo2O4 materials, CuCo2O4 (50:50) expressed not as much of crystallinity due to the agglomerated nanospheres. On the other hand, well crystalline CuCo2O4 (75:25) displayed higher surface area than the other materials when analysed through Brunauer-Emmett-Teller (BET) method. The Fourier transform infra-red (FTIR) spectrum has evinced the formation of CuCo2O4 nanostructures. In addition, the cubic spinel structured CuCo2O4 provided positive results over visible light irradiation. Finally, the CuCo2O4 (75:25) sample has scored high as much of 85% MO degradation compared with others. This sample was progressed with repetitive recycling tests and presented the best photocatalytic degradation efficiency. The upgraded results of CuCo2O4 sample have been linked with the developed synergistic effects during the formation of binary metal oxides. Also, the interfacial electron-hole formation leads to the migration and hindering of charge carriers for visible light activity.


Assuntos
Cobre
9.
Anal Chim Acta ; 1237: 340597, 2023 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-36442932

RESUMO

Bacterial contamination is a serious concern for health and environmental safety. The major toxic effect arises from the endotoxin or lipopolysaccharide (LPS) attached to the cell wall of the gram-negative bacteria. Ultrasensitive endotoxin detection is of supreme importance in sustaining food, clinical and pharmaceutical safety. Herein we report a simple electrochemical detection platform using reduced graphene oxide (rGO) combined with cuprous oxide nanoparticles for the ultrasensitive detection of LPS. The sensor uses polymyxin B (PmB) to achieve the selective response towards LPS. The sensor showed a lower detection limit (LOD) of 10 agmL-1 with linearity from 10 agmL-1 to 10 ngmL-1. Detection of LPS from whole blood is also carried out with excellent sensitivity. The sensor showed excellent recovery rates in whole blood, pointing to the capability of using the sensor in real-life clinical analysis. The sensor detects Gram-negative bacteria from sewage water with a rapid response time, indicating the effectiveness of the sensor in water quality analysis.


Assuntos
Cobre , Óxidos , Endotoxinas , Lipopolissacarídeos , Bactérias Gram-Negativas
10.
Biosens Bioelectron ; 221: 114210, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-35718654

RESUMO

Designing a universal route for rational synthesis of a family of hollow multinary chalcogenide semiconductors for photoelectrochemical biosensors is still facing to the enormous challenges ahead. Herein a template-assisted Cu2O surface vulcanization and etching through a Pearson's hard and soft acid-base (HSAB) principle was utilized to synthesize hollow Cu2-xS photoactive materials for photocurrent detection of prostate-specific antigen (PSA). We initially synthesized cubic Cu2O and further surface sulfidation and HCl etching to obtain cubic Cu2-xS. Inspiringly, stirring of CuS, phosphine (TBP: tributylphosphine) and other metal salts could replace Cu+ ions to obtain new metal sulfides without changing the framework, size and thickness of the original material. This interesting phenomenon could be explained by HSAB theory, which soft base was favorable for combining soft acid (Cu+) to drive Cu+ out of the framework. Based on the results, HSAB-based reaction system was applied to develop novel photoelectrochemical PSA immunoassay. Polymetallic-doped sulfides (ZnxCd1-xS) had better photocurrent response than pure binary sulfides. A copper oxide (CuO)-labeled detection antibody is captured in a microplate along with a sandwich immunoassay in the presence of target PSA. Subsequently, the CuO nanoparticles were dissociated by hydrochloric acid, releasing a large amount of copper ions to participate in the cation exchange reaction with ZnxCd1-xS. Such excellent photoelectric conversion materials could sensitively detect target PSA with a wide linear range from 1.0 pg/mL to 10 ng/mL at a limit of detection down to 0.32 pg/mL. Additionally, favorable stability, great anti-interference ability, easy-fabrication, low-cost, and satisfactory accuracy for the analysis of actual samples were acquired. Importantly, the concept of cation exchange reaction can be widely used to synthesize advanced nanomaterials for fabrication of high-efficiency biosensing systems.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Humanos , Masculino , Técnicas Biossensoriais/métodos , Antígeno Prostático Específico/análise , Técnicas Eletroquímicas/métodos , Limite de Detecção , Cádmio , Imunoensaio/métodos , Cobre , Sulfetos
11.
Eur J Med Chem ; 245(Pt 1): 114897, 2023 Jan 05.
Artigo em Inglês | MEDLINE | ID: mdl-36368059

RESUMO

Two Cu(II) (C1) and Ni(II) (C2) complexes were designed through the one-pot reaction of pyridine-2,6-dicarboxylic acid and 2-aminobenzimidazole respectively with copper(II) nitrate hexahydrate and nickel(II) nitrate hexahydrate. Both complexes were characterized by single-crystal X-ray diffraction and the distorted octahedral geometry was recognized for them. The MTT assay indicated that the complexes have a significant antiproliferative effect on BEL-7404 cells. IC50 values confirmed that C1 (IC50 = 0.56 µM) is several times more potent than C2 (IC50 = 5.13 µM). The similar cellular uptake of the complexes in mentioned cells led to this proposal that the production of ROS with different values can be the main reason for different cytotoxicity of the complexes. In this study, C1 and C2 caused BEL-7404 cells arrest at the G2/M and S phases, respectively. The expression of p53, Bax up-regulation, and Bcl-2 down-regulation and also activation of procaspase-9, and 3 indicated that apoptosis through a caspase-dependent mitochondrion pathway is a remarkable pathway in BEL-7404 cells treated by C1 while mechanistic studies proved that C2 induce death of BEL-7404 cells through the activation of RAGE/PI3KC3/Beclin 1 autophagic cell signaling pathway, more specifically. The cytostatic effect of the complexes in the BEL-7404 3D spheroid model was depicted.


Assuntos
Antineoplásicos , Complexos de Coordenação , Complexos de Coordenação/farmacologia , Complexos de Coordenação/química , Antineoplásicos/farmacologia , Antineoplásicos/química , Cobre/química , Metais/farmacologia , Apoptose , Piridinas/farmacologia , Ligantes
12.
Environ Pollut ; 316(Pt 2): 120639, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36372367

RESUMO

The pollution of nanoparticles (NPs) has linked with severe negative effects on crop productivity. Thus, effective strategies are needed to mitigate the phytotoxicity of NPs. The aim of present study was to evaluate the efficacy of exogenously applied melatonin (MT) in mitigating the toxic effects of copper oxide nanoparticles (CuO NPs) from maize seedlings. Therefore, we comprehensively investigated the inhibitory effects of MT against CuO NPs-induced toxicity on morpho-physiological, biochemical and ultrastructural levels in maize. Our results show that CuO NPs (300 mg L-1) exposure displayed significantly reduction in all plant growth traits and induced toxicity in maize. Furthermore, 50 µM MT provided maximum plant tolerance against CuO NPs-induced phytotoxicity. It was noticed that MT improved plant growth, biomass, photochemical efficiency (Fv/Fm), chlorophyll contents (Chl a and Chl b), SPAD values and gas exchange attributes (stomatal conductance, net photosynthetic rate, intercellular CO2 concentration and transpiration rate) under CuO NPs stress. In addition, MT enhanced the antioxidant defense system and conferred protection to ultrastructural (mainly chloroplast, thylakoids membrane and plastoglobuli) damages and stomatal closure in maize plants subjected to CuO NPs stress. Together, it can be stated that the exogenous supply of MT improves the resilience of maize plants against the CuO NPs-induced phytotoxicity. Our current findings can be useful for the enhancement of plant growth and yield attributes in CuO NPs-contaminated soils. The reported information can provide insight into the MT pathways that can be used to improve crop stress tolerance in a challenging environment.


Assuntos
Melatonina , Nanopartículas Metálicas , Nanopartículas , Cobre/química , Plântula , Antioxidantes/farmacologia , Antioxidantes/metabolismo , Melatonina/farmacologia , Melatonina/metabolismo , Zea mays/metabolismo , Nanopartículas/toxicidade , Óxidos/farmacologia , Nanopartículas Metálicas/toxicidade , Nanopartículas Metálicas/química
13.
Anal Chim Acta ; 1238: 340607, 2023 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-36464432

RESUMO

Copper nanoclusters (Cu NCs) were a new class of non-toxic and economical nanoprobe. However, the low luminescence performance and instability of Cu NCs limited the actual application. Herein, this work developed the novel controllable assembly of Cu NCs aggregation as the electrochemiluminescence (ECL) emitter. Firstly, the hydrophilic Cu NCs was located into the micelles in the reverse microemulsion system. Due to the uniform size of micelles, the number of Cu NCs in each micelle can be controlled exactly. Cerium ions were added to induce Cu NCs to accumulate in micelles. The strong aggregation induced ECL (AIECL) signal can be observed in the controllable assembly of Cu NCs aggregation. The nano-sized Cu NCs assembly not only possessed more strong luminescence and better stability than original Cu NCs, but also kept the good dispersibility over the aggregated bulk. Furthermore, SnS2 nanosheets increased the specific surface area of the electrode and the number of reactive sites, which further modulated electron transfer to amplify the ECL signal. The ECL sensing system was used to detect miRNA-455-3p in the triple-negative breast cancer tumor tissues. The work provided the new pathway to prepare Cu NCs assembly and expanded AIECL-based sensing application.


Assuntos
Cério , MicroRNAs , Micelas , Cobre , Luminescência
14.
J Nutr Biochem ; 111: 109180, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36240958

RESUMO

Myocardial ischemia leads to cardiac fibrosis along with copper (Cu) loss. Cu repletion diminishes myocardial fibrosis and improves cardiac function. The transformation of fibroblasts to myofibroblasts is highly responsible for the pathogenesis of cardiac fibrosis. This study was undertaken to test the hypothesis that Cu inhibition of cardiac fibrosis results from suppression of myofibroblasts. Rhesus monkeys 4-5 years old were subjected to coronary artery ligation to induce myocardial infarction (MI). At the end of the fourth week after the surgery, an ultrasound-directed Cu-albumin microbubble organ-specific Cu delivery technique was used to treat the ischemia-infarcted monkey hearts twice a week for 4 weeks. This treatment increased Cu concentrations in the infarct area, loosened the collagen cross-linking network, restored blood vessel density, and improved cardiac contractility. Total fibroblasts labeled with vimentin were increased in the infarct area, and Cu repletion did not alter this increase. Myofibroblasts, dually labeled with vimentin and α-smooth muscle actin (α-SMA), were also significantly increased in the infarct area but were significantly reduced by Cu repletion. Correspondingly, the products of myofibroblasts, type I and III collagens and inhibitors of collagenases were significantly reduced. In contrast, metalloproteinase-1 (MMP-1) and MMP-1 producing fibroblasts (vimentin+ and MMP-1+ cells) were significantly increased. These results suggest that Cu inhibits the transformation of fibroblasts to myofibroblasts, leading to a pro-fibrinolytic switch and an improvement in cardiac function.


Assuntos
Cobre , Infarto do Miocárdio , Miofibroblastos , Cobre/farmacologia , Fibroblastos , Fibrose , Metaloproteinase 1 da Matriz , Miocárdio/patologia , Miofibroblastos/patologia , Vimentina , Macaca mulatta , Animais
15.
Appl Radiat Isot ; 191: 110518, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36327610

RESUMO

Radiometals play a fundamental role in the development of personalized nuclear medicine. In particular, copper radioisotopes are attracting increasing interest since they offer a varying range of decay modes and half-lives and can be used for imaging (60Cu, 61Cu, 62Cu and 64Cu) and targeted radionuclide therapy (64Cu and 67Cu), providing two of the most promising true theranostic pairs, namely 61Cu/67Cu and 64Cu/67Cu. Currently, the most widely used in clinical applications is 64Cu, which has a unique decay scheme featuring ß+-, ß--decay and electron capture. These characteristics allow its exploitation in both diagnostic and therapeutic fields. However, although 64Cu has extensively been investigated in academic research and preclinical settings, it is still scarcely used in routine clinical practice due to its insufficient availability at an affordable price. In fact, the most commonly used production method involves proton irradiation of enriched 64Ni, which has a very low isotopic abundance and is therefore extremely expensive. In this paper, we report on the study of two alternative production routes, namely the 65Cu(p,pn)64Cu and 67Zn(p, α)64Cu reactions, which enable low and high 64Cu specific activities, respectively. To optimize the 64Cu production, while minimizing the mass of copper used as a target in the first case, or the co-production of other copper radioisotopes in the second case, an accurate knowledge of the production cross sections is of paramount importance. For this reason, the involved nuclear reaction cross sections were measured at the Bern medical cyclotron laboratory by irradiating enriched 65CuO and enriched 67ZnO targets. On the basis of the obtained results, the production yield and purity were calculated to assess the optimal irradiation conditions. Several production tests were performed to confirm these findings.


Assuntos
Radioisótopos de Cobre , Ciclotrons , Medicina de Precisão , Cobre , Diagnóstico por Imagem/métodos , Compostos Radiofarmacêuticos/uso terapêutico
16.
J Hazard Mater ; 443(Pt B): 130255, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36327844

RESUMO

Mining-impacted environments are distributed globally and have become increasingly recognized as hotspots of antibiotic resistance genes (ARGs). However, there are currently no reports on treatment technologies to deal with such an important environmental problem. To narrow this knowledge gap, we implemented a phytostabilization project in an acidic copper mine tailings pond and employed metagenomics to explore ARG characteristics in the soil samples. Our results showed that phytostabilization decreased the total ARG abundance in 0-10 cm soil layer by 75 %, which was companied by a significant decrease in ARG mobility, and a significant increase in ARG diversity and microbial diversity. Phytostabilization was also found to drastically alter the ARG host composition and to significantly reduce the total abundance of virulence factor genes of ARG hosts. Soil nutrient status, heavy metal toxicity and SO42- concentration were important physicochemical factors to affect the total ARG abundance, while causal mediation analysis showed that their effects were largely mediated by the changes in ARG mobility and microbial diversity. The increase in ARG diversity associated with phytostabilization was mainly mediated by a small subgroup of ARG hosts, most of which could not be classified at the genus level and deserve further research in the future.


Assuntos
Cobre , Lagoas , Cobre/toxicidade , Microbiologia do Solo , Resistência Microbiana a Medicamentos/genética , Solo/química , Antibacterianos/farmacologia
17.
J Hazard Mater ; 443(Pt B): 130265, 2023 02 05.
Artigo em Inglês | MEDLINE | ID: mdl-36327847

RESUMO

Herbicide residues in the environment threaten high-quality agriculture and human health. Consequently, in situ remediation of herbicide contamination is vital. We synthesized a novel self-catalyzed nanozyme, ultrasmall (2-3 nm) copper peroxide nanodots modified by citric acid (CP@CA) for this purpose, which can break down into H2O2 and Cu2+ in water or soil. Ubiquitous glutathione reduces Cu2+ into Cu+, which promotes the decomposition of H2O2 into •OH through a Fenton-like reaction under mild acid conditions created by the presence of citric acid. The generated •OH efficiently degrade nicosulfuron in water and soil, and the maximum degradation efficiency could be achieved at 97.58% in water at 56 min. The possible degradation mechanisms of nicosulfuron were proposed through the 25 intermediates detected. The overall ecotoxicity of the nicosulfuron system was significantly reduced after CP@CA treatment. Furthermore, CP@CA had little impact on active components of soil bacterial community. Moreover, CP@CA nanozyme could effectively remove seven other sulfonylurea herbicides from the water. In this paper, a high-efficiency method for herbicide degradation was proposed, which provides a new reference for the in situ remediation of herbicide pollution.


Assuntos
Herbicidas , Humanos , Herbicidas/metabolismo , Cobre/toxicidade , Ácido Cítrico , Peróxido de Hidrogênio/metabolismo , Peróxidos , Compostos de Sulfonilureia/toxicidade , Compostos de Sulfonilureia/metabolismo , Solo/química , Água
18.
Environ Res ; 216(Pt 2): 114567, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36244441

RESUMO

The recovery of heavy metals from electroplating sludge is important for alleviating heavy metal pollution and recycling metal resources. However, the selective recovery of metal resources is limited by the complexity of electroplating sludge. Herein, CuFe bimetallic Fenton-like catalysts were successfully prepared from electroplating sludge by a facile room-temperature ultrasonic-assisted co-precipitation method. The prepared CuFe-S mainly consisted of nanorods with diameters of 20-30 nm and lengths of 100-200 nm and a small number of irregular particles. Subsequently, we performed tetracycline (TC) degradation experiments, and the results showed that the product CuFe-S had very good performance over a wide pH range (2-11). At an initial pH = 2, CuFe-S could degrade 91.9% of 50 mg L-1 TC aqueous solution within 30 min, which is better than that of a single metal catalyst. Free radical scavenging experiments and electron paramagnetic resonance (EPR) tests revealed that ·OH was the main active species for the degradation of TC by CuFe-S. In conclusion, a CuFe bimetallic Fenton-like catalyst was developed for the catalytic degradation of antibiotics, which provides a novel technical route for the resource utilization of electroplating sludge and shows an important practical application prospect.


Assuntos
Metais Pesados , Esgotos , Galvanoplastia , Cobre , Catálise , Antibacterianos , Peróxido de Hidrogênio
19.
Sci Total Environ ; 857(Pt 3): 159488, 2023 Jan 20.
Artigo em Inglês | MEDLINE | ID: mdl-36265623

RESUMO

The concentration of copper ions (Cu2+) in the environment is closely related to water quality, food, and biological health. As an indispensable metal element for the human body, its content is closely related to many diseases. However, the current detection methods for Cu2+ have some limitations, such as complicated operations and unfavorable on-site analysis. Therefore, this work constructs a novel ratiometric fluorescent probe (QLP), which has the advantages of rapid response, good anti-interference ability and high sensitivity. It has been successfully used for the detection of Cu2+ in water samples, soil, and food. In addition, low cytotoxicity and strong tissue penetration make it suitable for the detection of Cu2+ in living cells and zebrafish, offering a chemical tool for exploring the physiological and pathological processes related to Cu2+. It is important to use probe QLP and portable UV lamp to create an easy-to-operate Cu2+ detection platform, which can quickly detect Cu2+ on-site by combining with a smartphone. This work not only provides a detection tool for on-site analysis of Cu2+, but also provides a reference strategy for the development of on-site detection methods for other environmental pollutants.


Assuntos
Cobre , Smartphone , Animais , Humanos , Cobre/análise , Peixe-Zebra , Íons/análise , Corantes Fluorescentes , Espectrometria de Fluorescência
20.
Environ Res ; 216(Pt 2): 114591, 2023 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-36272586

RESUMO

Coal pyrolysis wastewater (CPW) contained all kinds of toxic and harmful components, which would seriously threaten the natural environment and human health. However, the traditional advanced oxidation processes frequently failed to remove phenolic substances. An A2BO4-type perovskite (La2CuO4) was successfully synthesized through sol-gel process and first applied in the treatment of CPW. More than 90% of 3, 5-dimethylphenol (DMP) was removed within 200 min at neutral conditions. Moreover, La2CuO4 also displayed excellent catalytic activity and stability in the actual CPW treatment process. Results demonstrated that DMP was removed through the attack of ∙OH, ∙O2- and 1O2 in La2CuO4/H2O2 system. The La2CuO4 were more favorable for H2O2 activation and have a lower adsorption energy than LaFeO3. XPS of fresh and spent La2CuO4 illustrated that the decomposition of hydrogen peroxide (H2O2) was mainly due to the redox cycle between surface copper and oxygen species. Moreover, the possible degradation pathway of DMP was deduced by identifying degradation products and analyzing density functional theory (DFT) calculations. This research provided a novel strategy for the development of perovskite-based catalytic materials on the treatment of practical CPW.


Assuntos
Peróxido de Hidrogênio , Águas Residuárias , Humanos , Carvão Mineral/análise , Cobre , Pirólise , Óxidos , Oxirredução
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