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1.
Heliyon ; 10(3): e25509, 2024 Feb 15.
Artigo em Inglês | MEDLINE | ID: mdl-38333782

RESUMO

Wood vinegar is a high-value acidic byproduct of biomass pyrolysis used for charcoal production. It is widely used in agriculture and forestry. The adverse effects of synthetic fungicides on the environment and human health have prompted the increasing use of biofungicides as alternatives to traditional products in integrated plant disease management programs. In recent years, there has been an increasing interest in the potential of wood vinegar as a disease management tool in agriculture and forestry. In this paper, the composition and preparation process of wood vinegar and its application in agriculture and forestry were introduced, and the effect and mechanism of wood vinegar against fungi, viruses and bacteria were summarized. The potential of wood vinegar as a sustainable and eco-friendly alternative to conventional chemical fungicides is also discussed. Finally, some suggestions on the application and development of wood vinegar were put forward.

2.
Anal Chem ; 96(13): 5095-5105, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38414104

RESUMO

Carbon dot (C-dot) separation/purification is not only a fundamental chemical issue but also an essential precondition for revealing C-dots' true nature. To date, adequate separation of C-dots has remained an open question due to the lack of an appropriate fine separation system. Herein, we discover and reveal that polyamide chromatography can provide versatile and powerful performances for C-dot separation. By a joint study of experiments and all-atom molecular dynamics simulations, we demonstrate that multiple interaction forces, including electrostatic repulsion/attraction, hydrogen bond, and van der Waals effects, exist simultaneously among the stationary phase, mobile phase, and the separated C-dots. Furthermore, the magnitude of these forces is dependent on the surface chemistry of the separated C-dots and the nature of the used mobile phases, providing a theoretical basis and experimental operability for C-dot separation. So, the proposed system possesses the capacity for adequately separating hydrophilic, amphiphilic, and lipophilic C-dots. The polyamide chromatography, due to its versatile and powerful separation performances, not only provides more thorough separation effects but also helps to correct our false perceptions from inadequate purified C-dots.

3.
Sci Total Environ ; 921: 171019, 2024 Apr 15.
Artigo em Inglês | MEDLINE | ID: mdl-38382605

RESUMO

Choosing a good crop rotation plan helps maintain soil fertility and creates a healthy soil ecosystem. However, excessive fertilization and continuous cultivation of vegetables in a greenhouse results in secondary salinization of the soil. It remains unclear how crop rotation affects Yunnan's main place for vegetable growing in the greenhouse. Six plant cultivation patterns were chosen to determine how different rotation patterns affect the chemical properties and the soil microbial communities with secondary salinization, including lettuce monoculture, lettuce-large leaf mustard, lettuce-red leaf beet, lettuce-cabbage, lettuce-romaine lettuce, and lettuce-cilantro (DZ, A1, A2, A3, A4, and A5). The results showed that all treatments increased the proportion of nutrients available in the soil, and the effect of the A1 treatment was the most significant compared to the monoculture mode. The high-throughput sequencing findings revealed that distinct crop rotation patterns exerted varying effects on the microbial communities. Microbial community diversity was significantly lower in the monoculture than in the other treatments. The number of microbial operational taxonomic units OTUs was significantly higher in the crop rotation modes (P < 0.05), and the A1 treatment had larger numbers and diversity of bacterial and fungal OTUs (Shannon's and Simpson's) than other treatments (P < 0.05). Prominent bacterial and fungal communities were readily observable in the soils planted with rotational crops. Proteobacteria had the highest relative abundance of bacteria, whereas Ascomycota was the most abundant fungus. The principal coordinate analysis at the OTU level separated soil bacterial and fungal growth communities under the different treatments. Among the six treatments, The first two axes (PC1 and PC2) described 46.44 % and 42.42 % of the bacterial and fungal communities, respectively. Network-based analysis showed that Bacteroidota and Gemmatimonadota members of the genus Bacteroidota were positively correlated with Proteobacteria. Members of Ascomycota and Chytridiomycota exhibited positive relationships. These results extend the theoretical understanding of how various crop rotation patterns affect soil chemical properties, microbial community diversity, and metabolic functions. They reveal the beneficial effects of crop rotation patterns on enhanced soil quality. This study provides theoretical guidance for the future enhancement of sustainable agriculture and soil management planning.


Assuntos
Ascomicetos , Microbiota , Solo/química , Verduras , Microbiologia do Solo , China , Bactérias
4.
Langmuir ; 40(6): 2979-2989, 2024 Feb 13.
Artigo em Inglês | MEDLINE | ID: mdl-38286810

RESUMO

For nanocrystals (NCs) self-assembly, understanding the chemical and supramolecular interactions among building blocks is significant for both fundamental scientific interests and rational nanosuperstructure construction. However, it has remained an extreme challenge for many self-assembly systems due to the lack of appropriately quantitative approaches for the corresponding exploration. Herein, by combination of the proposed colorimetric method for cationic surfactant quantitation and all-atom simulations, we manage to present a clear chemical picture for the thiol molecules modulated self-assembly of gold nanorods (GNRs), one of the earliest and most convenient methods for the fabrication of freestanding GNR self-assemblies. It is revealed that the self-assembly of GNRs is driven by the hydrophobic effects of the alkyl chains of the modified cationic surfactants, as their bilayer structure is destroyed by the added thiol molecules. In other words, the actual roles of the thiol molecules for causing GNRs assembly are indirectly inductive effects instead of the previously believed direct electrostatic attraction and/or hydrogen-bond linking effects of the binding thiol molecules. Furthermore, the GNRs exhibit diameter-dependent assembly behaviors: thicker GNRs tend to adopt the end-to-end assembly mode, while thin ones prefer the side-by-side assembly mode, further demonstrating that hydrophobic effects among the build blocks are the driving force for the GNRs assembly.

5.
Plants (Basel) ; 13(2)2024 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-38256711

RESUMO

Wood vinegar, a by-product of charcoal biomass pyrolysis, has been used as a biofungicide in plant disease management because of its antimicrobial properties. However, the physiological and biochemical mechanisms through which wood vinegar alleviates biotic stress are poorly understood. In this study, pot experiments were conducted to investigate the resistance and regulation mechanism of wood vinegar prepared from different raw materials (ZM) and from a single raw material (SM) in controlling tomato (Solanum lycopersicum "Bonny Best") Fusarium wilt at different concentrations (0.3%, 0.6%, 0.9%, 1.2%, and 1.5%). The results showed that ZM and SM had significant control effects on tomato fusarium wilt under different concentrations in the same growth cycle. Under biotic stress, the two kinds of wood vinegar significantly increased the plant height, stem diameter, leaf area and yield of tomato under the concentration of 0.3%, 0.6%, 0.9% and 1.2%, and significantly reduced the content of malondialdehyde (MDA) and hydrogen peroxide (H2O2) in tomato leaves. The effect of 0.9% treatment was the most significant, ZM and SM significantly increased tomato yield by 122% and 74%, respectively, compared with CK under 0.9% treatment. However, the plant height, stem diameter and leaf area of tomato were significantly reduced under 1.5% treatment, but the content of soluble sugar, soluble protein and vitamin C in tomato fruit was the best. Compared with CK, ZM significantly increased by 14%, 193% and 67%, respectively, and SM significantly increased by 28%, 300% and 159%, respectively. Except for 0.3% treatment, both significantly increased the activities of catalase (CAT), peroxidase (POD) and superoxide dismutase (SOD) in tomato leaves. The response intensity of two kinds of wood vinegar-physiological and biochemical-to tomato disease resistance, growth and development, showed ZM > SM. The disease index of tomato showed highly significant negative correlation with plant height, stem thickness, leaf area and antioxidant physiology CAT, and highly significant positive correlation with MDA and H2O2 content. In conclusion, ZM was more effective than SM in enhancing tomato disease resistance by promoting tomato growth and development, decreasing leaf MDA and H2O2 content, and inducing antioxidant enzyme activity in leaves at moderate concentrations.

6.
Huan Jing Ke Xue ; 44(9): 5196-5203, 2023 Sep 08.
Artigo em Chinês | MEDLINE | ID: mdl-37699837

RESUMO

To explore the safe utilization technology of farmland polluted by the heavy metals cadmium (Cd) and lead (Pb) and to realize the safe production of agricultural products, a pot experiment was conducted to investigate the effects of two soil passivators and five foliar inhibitors on Cd and Cd-accumulation and quality of lettuce with low Pb and Cd accumulation (KCW). The results showed that different control measures had different effects on the soil pH value of lettuce, and the application of 45 g·m-2biochar-based passivator had the most significant difference in improving the soil pH value, which was increased by 0.8 units compared with that in CK. By using 72 g·m-2 of humic acid passivator yielded notable difference in reducing the soil pH value of lettuce. A reduction of 0.25 units was achieved compared with that in CK. Among all the control measures, the application of 45 g·m-2 biocharcoal-based passivation agent had the best effect on reducing soil available Cd content, which was significantly reduced by 53% compared with that in CK, and the application of 135 g·m-2biocharcoal-based passivation agent had the best effect on reducing soil available Pb content, which was significantly reduced by 64% compared with that in CK. Spraying 0.8% FAK-Zn foliar inhibitor not only had the best control effect on reducing Cd and Pb contents in the edible parts of lettuce, which were significantly reduced by 77% and 60%, respectively, compared with that in CK, but it also significantly reduced Cd and Pb enrichment coefficients and transport coefficients from the root to the edible parts of the lettuce. Different control measures had different effects on the nutritional quality of lettuce, and 0.4% FAK-Zn foliar inhibitor had the best effect on soluble protein. The 0.6% FAK-Zn had the best effect on soluble sugar, and the 0.4% FAK-Zn inhibitor had the best effect on vitamin C content. The application of biocarbon-based passivator could effectively repair lettuce soil polluted by Cd and Pb, whereas the application of FAK-Zn leaf surface inhibitor could effectively inhibit the accumulation, absorption, and transfer of Cd and Pb in lettuce; improve the nutritional quality of lettuce; provide a theoretical basis for safe production of vegetables polluted by heavy metals; and promote the recycling of resources and environment.


Assuntos
Cádmio , Lactuca , Chumbo , Verduras , Solo
7.
J Fungi (Basel) ; 9(6)2023 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-37367613

RESUMO

Arbuscular mycorrhizal fungi (AMF) play key roles in enhancing plant tolerance to heavy metals, and iron (Fe) compounds can reduce the bioavailability of arsenic (As) in soil, thereby alleviating As toxicity. However, there have been limited studies of the synergistic antioxidant mechanisms of AMF (Funneliformis mosseae) and Fe compounds in the alleviation of As toxicity on leaves of maize (Zea mays L.) with low and moderate As contamination. In this study, a pot experiment was conducted with different concentrations of As (0, 25, 50 mgꞏkg-1) and Fe (0, 50 mgꞏkg-1) and AMF treatments. Results showed that under low and moderate As concentrations (As25 and As50), the co-inoculation of AMF and Fe compound significantly increased the biomass of maize stems and roots, phosphorus (P) concentration, and P-to-As uptake ratio. Moreover, the co-inoculation of AMF and Fe compound addition significantly reduced the As concentration in stem and root, malondialdehyde (MDA) content in leaf, and soluble protein and non-protein thiol (NPT) contents in leaf of maize under As25 and As50 treatments. In addition, co-inoculation with AMF and Fe compound addition significantly increased the activities of catalase (CAT), peroxidase (POD), and superoxide dismutase (SOD) in the leaves of maize under As25 treatment. Correlation analysis showed that stem biomass and leaf MDA content were very significantly negatively correlated with stem As content, respectively. In conclusion, the results indicated that the co-inoculation of AMF and Fe compound addition can inhibit As uptake and promote P uptake by maize under low and moderate As contamination, thereby mitigating the lipid peroxidation on maize leaves and reducing As toxicity by enhancing the activities of antioxidant enzymes under low As contamination. These findings provide a theoretical basis for the application of AMF and Fe compounds in the restoration of cropland soil contaminated with low and moderate As.

8.
Nanoscale Adv ; 5(4): 1190-1198, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36798509

RESUMO

Supraparticles (SPs) are of great importance in both fundamental and applied studies due to their emerging collective properties, synergistic effects, and various applications. Metal sulfide nanomaterials are of vital importance in biomedicine, catalysis, battery materials, and other fields. Herein, an in situ decomposition-assembly strategy for the versatile fabrication of metal sulfide SPs is developed. In the fabrication, cysteine molecules and metal cations first react and form coordination polymers, which are then decomposed by heating to produce small-sized metal sulfide nanocrystals. Driven by elimination of the high surface energy of NCs generated by thermal decomposition and the van der Waals attraction, the resulting nanocrystals in situ self-assemble each other and form SP products. In addition to homogeneous Cu2S, CdS, and ZnS products, the proposed system can even be extended to fabricate hybrid Cu2S/Fe2O3 SPs. Furthermore, the SP size can be easily tuned from 10 to 100 nm by adjusting the proportion of cysteine and metal ions. The SPs not only exhibit various properties including photothermal conversion, fluorescence, and magnetism, depending on their composition, but can also combine these properties by the formation of hybrid structures.

9.
Anal Chem ; 95(5): 2765-2773, 2023 02 07.
Artigo em Inglês | MEDLINE | ID: mdl-36512489

RESUMO

Exploring the etiology of liver injury is critical to fundamental science and precise treatment, which has not yet been achieved by molecule imaging techniques. Herein, we manage to conquer this challenge by spatiotemporally monitoring oxidative stress processes using the proposed unit-emitting carbon dots (UE-C-dots) as fluorescent probes. We discover and reveal that the UE-C-dots can specifically determine hypochlorous acid (HClO) molecules, one of the important reactive oxygen/nitrogen species (ROS/RNS) in liver injury, by an excited state oxidation mechanism. Other ROS/RNS do not interfere with the assay even if their concentrations are 1000 times higher than that of HClO due to the lowest unoccupied molecular orbital level mismatch. Real-time tomographic imaging demonstrates that different stimuli cause distinctly different HClO bursts in both temporal and spatial dimensionalities. Therefore, the measurement and analysis of temporal information substantially extend our understanding on the relationships of hepatic oxidative stress and corresponding physiological/pathological behaviors.


Assuntos
Carbono , Estresse Oxidativo , Espécies Reativas de Oxigênio/análise , Ácido Hipocloroso/análise , Oxigênio , Espécies Reativas de Nitrogênio/análise , Corantes Fluorescentes , Fígado/química , Nitrogênio
10.
Bull Environ Contam Toxicol ; 107(6): 1155-1160, 2021 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-34236456

RESUMO

Agricultural arsenic (As, CAS. No. 7440-38-2) over the issue of pollution has been related to people's livelihood, security and moderate use of As contaminated soil is an important aspect of contaminated soil remediation. In this potted plant experiment, synergistic effects of arbuscular mycorrhizal fungi (AMF) Funneliformis mosseae and iron (Fe, CAS. No. 7439-89-6) oxides on plant growth and phosphorus (P, CAS. No. 7723-14-0), As and Fe uptake by maize (Zea mays L.) were studied on simulating medium As-polluted soils in greenhouse. Different amounts (0, 5, 10, 20, 40 g kg- 1) of iron tailings (IT) were added. The results showed that IT20 and IT40 addition significantly increased mycorrhizal infection rate, plant biomass, root length and P, Fe uptake under FM treatment; IT40 addition decreased As concentration in roots. In addition, FM inoculation increased biomass, root length and P uptake by shoots, but decreased Fe and As concentration in shoots. Therefore, the combined FM inoculation and IT40 addition promoted maize growth and decreased As concentration in shoots by decreasing As absorption efficiency, increasing P and Fe uptake and P/As ratio.


Assuntos
Arsênio , Micorrizas , Poluentes do Solo , Arsênio/toxicidade , Biodegradação Ambiental , Fungos , Ferro , Micorrizas/química , Fósforo , Raízes de Plantas/química , Solo , Poluentes do Solo/análise , Poluentes do Solo/toxicidade , Zea mays
11.
Huan Jing Ke Xue ; 42(8): 3963-3970, 2021 Aug 08.
Artigo em Chinês | MEDLINE | ID: mdl-34309283

RESUMO

To investigate the dominant plants in ecological restoration of tin mining areas, field investigations were conducted in a tin tailings area in Lailishan, Yunnan Provence, and 15 dominant plants and corresponding rhizosphere soils were collected. The plant root mycorrhizal infection rate; the copper (Cu), cadmium (Cd), arsenic (As), nickel (Ni), lead (Pb), and tin (Sn) contents; and the chemical properties of the rhizosphere tailings were determined. The transfer and enrichment coefficients of six heavy metals were calculated for each of the 15 plants to comprehensively evaluate the application potential of native plants. The rhizophere tailings had an average pH value of 3.13, which was acidic. The organic matter, total nitrogen, total phosphorus, total potassium, alkaline hydrolyzed nitrogen, and available phosphorus content of the soils was 6.07 g ·kg-1, 5.74 g ·kg-1, 0.62 g ·kg-1, 8.66 g ·kg-1, 30.84 mg ·kg-1, and 2.08 mg ·kg-1 respectively, indicating relatively nutrient-poor soil. The average Cu, Cd, Ni, Pb, As, and Sn contents of the soils were 347.40, 1.02, 1.34, 168.47, 25.81, and 2299.02 mg ·kg-1, respectively. Among the heavy metals, the Cd content reached a third-level pollution warning value. The soil also contained a large amount of Cu and Pb which exhibited a different spatial distribution. This area appears to have a high risk of Cu, Pb, and Cd pollution. In addition, the roots of Olea europaea L. and Eurya japonica Thunb. had a high rate of mycorrhizal infection. Alnus cremastogyne Burk., Bambusa multiplex (Lour.) Raeusch. ex Schult. 'Alphonse-Kar' R. A. Young, Juncus effusus L., and Cyperus rotundus L. var. had a strong ability to absorb and transport heavy metals. The other plants were also adapted to the growth environment of the tin tailings, with the potential to restore the mining area.


Assuntos
Metais Pesados , Poluentes do Solo , China , Metais Pesados/análise , Solo , Poluentes do Solo/análise , Estanho
12.
Nanotheranostics ; 5(3): 275-287, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33654654

RESUMO

Development of intelligent and multifunctional nanoparticle for the diagnosis and treatment of cancer has drawn great attention recently. In this work, we design a smart two-dimensional (2D) supraparticle for tumor targeted magnetic resonance imaging (MRI)/photothermal imaging (PTI) and chemo/photothermal therapy (PTT). Methods: The nanoparticle consists of a manganese dioxide (MnO2) nanosheet coated gold nanorod (GNR) core (loading with chemotherapeutics doxorubicin (DOX)), and cancer cell membrane shell (denoted as CM-DOX-GMNPs). Decoration of cell membrane endows the nanoparticle with greatly improved colloidal stability and homotypic cancer cell targeting ability. Once the nanoparticles enter tumor cells, MnO2 nanosheets can be etched to Mn2+ by glutathione (GSH) and acidic hydrogen peroxide (H2O2) in the cytosol, leading to the release of DOX. Meanwhile, stimuli dependent releasing of Mn2+ can act as MRI contrast agent for tumor diagnosis. Illumination with near-infrared (NIR) light, photothermal conversion effect of GNRs can be activated for synergistic cancer therapy. Results:In vivo results illustrate that the CM-DOX-GMNPs display tumor specific MRI/PTI ability and excellent inhibition effect on tumor growth. Conclusion: This bioinspired nanoparticle presents an effective and intelligent approach for tumor imaging and therapy, affording valuable guidance for the rational design of robust theranostics nanoplatform.


Assuntos
Nanopartículas/química , Neoplasias/terapia , Medicina de Precisão , Antineoplásicos/administração & dosagem , Antineoplásicos/uso terapêutico , Membrana Celular , Doxorrubicina/administração & dosagem , Sistemas de Liberação de Medicamentos/métodos , Humanos , Imageamento por Ressonância Magnética , Neoplasias/diagnóstico por imagem , Terapia Fototérmica
13.
Environ Res ; 192: 110260, 2021 01.
Artigo em Inglês | MEDLINE | ID: mdl-33069700

RESUMO

A plasmonic photocatalyst of AgBr/BiPO4/g-C3N4 was prepared. X-ray powder diffraction, Scanning electron microscope, Transmission electron microscopy, Fourier infrared spectroscopy, Ultraviolet Visible diffuse reflectance spectroscopy and photoluminescence emission spectra have been employed to determine the structure, morphology and optical property of the as-prepared AgBr/BiPO4/g-C3N4 composite and analysis the reasons for improving photocatalytic efficiency. The optimal doping ratio of AgBr was 10 wt% by degrading 20 mg/L of Reactive Blue 19 (RB19) under visible light (λ > 420 nm), and 10 wt%AgBr/BiPO4/g-C3N4 degraded 20 mg/L of RB19 to 2.59% at 40 min, which is ascribed to synergistic effects at the interface of AgBr, BiPO4 and g-C3N4. The effect of catalyst dosage, initial concentration and initial pH of RB19 solution on photocatalytic efficiency was investigated. Four cycles of experiments were conducted. Finally, through the trapping experiment, we found that the main active factor for degrading RB19 in the photocatalytic process is O2-. The possible photocatalytic mechanism of AgBr/BiPO4/g-C3N4 was discussed in connection with the synergistic effect of Ag and active substances at the AgBr/BiPO4/g-C3N4 interface.


Assuntos
Grafite , Antraquinonas , Catálise , Luz
14.
Curr Microbiol ; 78(1): 329-337, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33175194

RESUMO

Phage therapy is an alternative approach to overcome the problem of multidrug-resistant bacteria. Here, a novel bacteriophage AhyVDH1, which infects Aeromonas hydrophila 4572, was isolated and its morphology, one-step growth curve, lytic activity, stability under various conditions, and genome were investigated. Transmission electron microscopy revealed that AhyVDH1 has an icosahedral head 49 nm in diameter and a contractile tail 127 nm in length, suggesting that it belongs to the family Myoviridae. AhyVDH1 showed strong adsorption to the surface of A. hydrophila 4572 (90% in 10 min). The latent period of AhyVDH1 was shown to be 50 min, and the burst size was 274 plaque-forming unit/infected cell. AhyVDH1 was stable at 30 °C for 1 h and lost infectivity after20 min of heating at 60 °C. Infectivity remained unaffected at pH 6-7 for 1 h, while the bacteriophage was inactivated at pH < 4 or > 11. AhyVDH1 has a 39,175-bp genome, with a 58% G + C content and 59 open reading frames. BLAST analysis indicated that the genome sequence of phage AhyVDH1 was related to that of Aeromonas phage Ahp2. Both time and MOI-dependent in vitro A. hydrophila growth inhibition were observed with AhyVDH1.Re-growth of the host bacteria appeared about 12 h after treatment, suggesting its potential therapeutic value in treating A. hydrophila infections, but phage cocktails should be developed.


Assuntos
Bacteriófagos , Terapia por Fagos , Aeromonas hydrophila , Bacteriófagos/genética , Farmacorresistência Bacteriana Múltipla , Genoma Viral , Myoviridae/genética
15.
J Mater Chem B ; 8(35): 7921-7930, 2020 09 21.
Artigo em Inglês | MEDLINE | ID: mdl-32756672

RESUMO

We herein report a (sacrificial template-ligand exchange) integration strategy to fabricate near-infrared optically active Cu2-xS nanocrystals (NCs) and further investigate their interactions with cells, autophagy-induced tumor cell death, and photothermal ablation application potential. Starting from oleic acid capped Cu@Cu2-xO NCs, water-soluble and chiral d- and l-cysteine modified Cu2-xS (denoted as d-Cu2-xS and l-Cu2-xS, respectively) NCs have been reliably obtained by ligand exchange (from oleic acid to cysteine) accompanied by the core chemical transformation (from Cu@Cu2-xO to Cu2-xS). The resulting two enantiomeric Cu2-xS NCs have almost identical physicochemical properties including size, morphology, chemical composition, extinction band, peroxidase mimicking activity, and photothermal stability. The only exception is that the d- and l-Cu2-xS NCs exhibit mirror symmetric circular dichroism signals ranging from the ultraviolet to near-infrared region. The cellular uptake of the d-Cu2-xS NCs is about three times higher than that of their enantiomeric counterparts, which is likely attributed to their higher affinity with the cytomembranes of tumor cells (HepG2 and HeLa cells). As a result, a more prominent cellular autophagy proceeds due to the more significant production of highly reactive oxygen species. Then, the ablation of cells can be further enhanced by photothermal effects of the Cu2-xS NCs. Meanwhile, for normal cells, due to very limited cellular uptake effects, little cytotoxicity has been observed for both d- and l-Cu2-xS NCs.


Assuntos
Autofagia/efeitos dos fármacos , Cobre/química , Cobre/farmacologia , Raios Infravermelhos , Nanopartículas/química , Fenômenos Ópticos , Células HeLa , Células Hep G2 , Humanos , Ligantes , Solubilidade , Estereoisomerismo , Água/química
16.
Chem Commun (Camb) ; 56(63): 8996-8999, 2020 Aug 14.
Artigo em Inglês | MEDLINE | ID: mdl-32638716

RESUMO

We herein present a reactive site regulation strategy for fabricating well-defined Janus and core@shell gold nanorod-Cu2-xS dual metal-semiconductor plasmonic supraparticles. In addition to enhanced photothermal efficiency and photostability, the nanohybrids possess synergetic photo-thermal and chemical dynamic therapy and corresponding application potential.

17.
ACS Nano ; 14(4): 4036-4044, 2020 04 28.
Artigo em Inglês | MEDLINE | ID: mdl-32196312

RESUMO

The exploration of magnetic resonance imaging (MRI) agents possessing excellent performances and high biosafety is of great importance for both fundamental science research and biomedical applications. In this study, we present that monodisperse Fe2O3 supraparticles (SPs) can act as T1-weighted MRI agents, which not only possess a distinct off-on MRI switch in the tumor microenvironment but also are readily excreted from living bodies due to its quasi-amorphous structure and hierarchical topology design. First, the Fe2O3 SPs have a surface-to-volume ratio obviously smaller than that of their building blocks by means of self-assembly processes, which, on the one hand, causes a rather low r1 relaxivity (0.19 mM-1 s-1) and, on the other hand, can effectively prevent their aggregation after intravenous injection. Second, the Fe2O3 SPs have a dramatic disassembly/degradation-induced active T1-weighted signal readout (more than 6 times the r1 value enhancement and about 20 times the r2/r1 ratio decrease) in the tumor microenvironment, resulting in a high signal-to-noise ratio for imaging performances. Therefore, they possess excellent in vivo imaging capacity, even with a tumor size as small as 5 mm3. Third, the disassembled/decomposed behaviors of the Fe2O3 SPs facilitate their timely clearance/excretion from living bodies. In particular, they exhibit distinct renal clearance behavior without any kidney damage with the right dosage. Fourth, the favorable biodegradability of the as-prepared Fe2O3 SPs can further relieve the concerns about the unclear biological effects, particularly on nanomaterials, in general.


Assuntos
Meios de Contraste , Nanoestruturas , Imageamento por Ressonância Magnética
18.
Angew Chem Int Ed Engl ; 58(31): 10542-10546, 2019 07 29.
Artigo em Inglês | MEDLINE | ID: mdl-31112336

RESUMO

We herein demonstrate robust two-dimensional (2D) UFO-shaped plasmonic supraparticles made of gold nanoparticles (AuNPs) and MnO2 nanosheets (denoted as AMNS-SPs) for directly monitoring cell membrane vesiculation at the single-particle level. Because the decorated MnO2 nanosheets are ultrathin (4.2 nm) and have large diameters (230 nm), they are flexible enough for deformation and folding for parceling of the AuNPs during the endocytosis process. Correspondingly, the surrounding refractive index of the AuNPs increases dramatically, which results in a distinct red-shift of the localized surface plasmon resonance (LSPR). Such LSPR modulation provides a convenient and accurate means for directly monitoring the dynamic interactions between 2D nanomaterials and cell membranes. Furthermore, for the endocytosed AMNS-SPs, the subsequent LSPR blue-shift induced by etching effects of reducing molecules is promising for exploring the local environment redox states at the single-cell level.


Assuntos
Membrana Celular/química , Ouro/química , Compostos de Manganês/química , Nanoestruturas/química , Óxidos/química , Análise de Célula Única , Comunicação Celular , Substâncias Macromoleculares/química , Tamanho da Partícula , Ressonância de Plasmônio de Superfície , Propriedades de Superfície
19.
Mikrochim Acta ; 186(1): 50, 2019 01 05.
Artigo em Inglês | MEDLINE | ID: mdl-30612201

RESUMO

This review (with 261 refs.) summarizes the progress that has been made in the field of in-vitro diagnosis using carbonaceous nanoparticles (CNPs). Signal readout is mostly based on fluorometry, electrochemistry and colorimetry. Following an introduction, the next two sections cover methods for the fabrication and separation of CNPs. This is followed by sections on (a) fluorometric methods, (b) electrochemical methods, and (c) colorimetric methods for detecting various analytes. Several subsections discuss detection schemes for analytes such as metal ions, pH value, reactive oxygen species, small biogenic molecules (for example glucose, ascorbic acid, amino acids, dopamine), and biomacromolecules (such as enzymes, cancer markers, DNA). A further section discusses methods based on the peroxidase-like activity of CNPs, and how they can be employed for the determination of species such as glucose, cholesterol, glutathione, and uric acid via H2O2-based chromogenic methods. Finally, the challenges and future perspectives in this research area are discussed. Graphical abstract A review is presented on the progress that has been made in recent years in sensing platforms for in-vitro diagnosis using carbonaceous nanoparticles (CNPs). Signal readout is mostly based on fluorometry, electrochemistry and colorimetry, respectively. Besides, the fabrication and separation strategies of CNPs are also demonstrated.


Assuntos
Técnicas Biossensoriais/métodos , Carbono/química , Meios de Contraste/química , Nanopartículas/química , Animais , Materiais Biocompatíveis/análise , Catálise , Diagnóstico por Imagem/métodos , Técnicas Eletroquímicas/métodos , Humanos , Íons/análise , Metais/análise , Compostos Orgânicos/análise , Pontos Quânticos/química , Espectrometria de Fluorescência/métodos
20.
J Basic Microbiol ; 59(2): 206-214, 2019 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-30284309

RESUMO

Exiguobacterium is a versatile genus with potential in industry and agriculture. No bacteriophage that infects Exiguobacterium has been reported, despite its potential impacts on the utilization of Exiguobacterium. E. indicum EI9 was isolated from Dianchi Lake, a plateau eutrophic lake in China, which can significantly inhibit the growth of Microcystis aeruginosa. To isolate and characterize Exiguobacterium-infecting bacteriophage, a virulent bacteriophage, DCEIV-9 that specifically infects E. indicum EI9 was isolated from Dianchi lake water sample. DCEIV-9 produced tiny, round, and clear plaques with 0.5-1 mm in diameter. Electron microscopy showed that DCEIV-9 is a typical representative of the Siphoviridae, with an icosahedral head (56 nm in diameter) and a non-contractile tail (163 nm in length). Based on a one-step growth curve, latent period of 20 min and burst size of 51 PFU/infected cell were determined. DCEIV-9 was sensitive to temperature over 50 °C and prefers acid environment. DCEIV-9 was extremely sensitive to proteinase K, chloroform, ethanol, Triton X-100 but not sensitive to SDS. Restriction endonucleases analysis indicated that DCEIV-9 is a dsDNA virus. DCEIV-9 can only infect E. indicum, indicates that it has a narrow host range. DCEIV-9 is a potential new species.


Assuntos
Bacillaceae/isolamento & purificação , Bacillaceae/virologia , Bacteriófagos/genética , Bacteriófagos/isolamento & purificação , Lagos/virologia , Bacillaceae/classificação , Bacillaceae/genética , Bacteriófagos/efeitos dos fármacos , Bacteriófagos/ultraestrutura , China , Vírus de DNA/genética , DNA Viral/genética , Endopeptidase K/farmacologia , Etanol/farmacologia , Genoma Viral , Especificidade de Hospedeiro , Concentração de Íons de Hidrogênio , Microcystis/crescimento & desenvolvimento , Microscopia Eletrônica , Octoxinol/farmacologia , RNA Ribossômico 16S/genética , Siphoviridae/classificação , Dodecilsulfato de Sódio/farmacologia , Temperatura
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