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1.
Small ; : e2403271, 2024 Jul 23.
Artigo em Inglês | MEDLINE | ID: mdl-39039981

RESUMO

2D transition metal carbides and nitrides, i.e., MXene, are recently attracting wide attentions and presenting competitive performances as adsorbents used in hemoperfusion. Nonetheless, the nonporous texture and easily restacking feature limit the efficient adsorption of toxin molecules inside MXene and between layers. To circumvent this concern, here a plerogyra sinuosa biomimetic porous titanium carbide MXene (P-Ti3C2) is reported. The hollow and hierarchically porous structure with large surface area benefits the maximum access of toxins as well as trapping them inside the spherical cavity. The cambered surface of P-Ti3C2 prevents layers restacking, thus affording better interlaminar adsorption. In addition to enhanced toxin removal ability, the P-Ti3C2 is found to selectively adsorb more middle and large toxin molecules than small toxin molecules. It possibly originates from the rich Ti-deficient vacancies in the P-MXene lattice that increases the affinity with middle/large toxin molecules. Also, the vacancies as active sites facilitate the production of reactive oxygen under NIR irradiation to promote the photodynamic antibacterial performance. Then, the versatility of P-MXene is validated by extension to niobium carbide (P-Nb2C). And the simulated hemoperfusion proves the practicability of the P-MXene as polymeric adhesives-free adsorbents to eliminate the broad-spectrum toxins.

2.
Small ; 20(12): e2307537, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37939303

RESUMO

Constructing effective and robust biocatalysts with carbonic anhydrase (CA)-mimetic activities offers an alternative and promising pathway for diverse CO2-related catalytic applications. However, there is very limited success has been achieved in controllably synthesizing CA-mimetic biocatalysts. Here, inspired by the 3D coordination environments of CAs, this study reports on the design of an ultrafast ZnN3-OH2 center via tuning the 3D coordination structures and mesoporous defects in a zinc-dipyrazolate framework to serve as new, efficient, and robust CA-mimetic biocatalysts (CABs) to catalyze the hydration reactions. Owing to the structural advantages and high similarity with the active center of natural CAs, the double-walled CAB with mesoporous defects displays superior CA-like reaction kinetics in p-NPA hydrolysis (V0 = 445.16 nM s-1, Vmax = 3.83 µM s-1, turnover number: 5.97 × 10-3 s-1), which surpasses the by-far-reported metal-organic frameworks-based biocatalysts. This work offers essential guidance in tuning 3D coordination environments in artificial enzymes and proposes a new strategy to create high-performance CA-mimetic biocatalysts for broad applications, such as CO2 hydration/capture, CO2 sensing, and abundant hydrolytic reactions.

3.
Biomacromolecules ; 25(5): 3141-3152, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38687279

RESUMO

Atherosclerosis (AS) is characterized by the accumulation of substantial low-density lipoprotein (LDL) and inflammatory response. Hemoperfusion is commonly employed for the selective removal of LDL from the body. However, conventional hemoperfusion merely focuses on LDL removal and does not address the symptom of plaque associated with AS. Based on the LDL binding properties of acrylated chondroitin sodium sulfate (CSA), acrylated beta-cyclodextrin (CD) and acrylic acid (AA), along with the anti-inflammatory property of rosiglitazone (R), the fabricated AA-CSA-CD-R microspheres could simultaneously release R and facilitate LDL removal for hemoperfusion. The AA and CSA offer electrostatic adsorption sites for LDL, while the CD provides hydrophobic adsorption sites for LDL and weak binding sites for R. According to the Sips model, the maximum static LDL adsorption capacity of AA-CSA-CD-R is determined to be 614.73 mg/g. In dynamic simulated perfusion experiments, AA-CSA-CD-R exhibits an initial cycle LDL adsorption capacity of 150.97 mg/g. The study suggests that the weakened inflammatory response favors plaque stabilization. The anti-inflammatory property of the microspheres is verified through an inflammation model, wherein the microsphere extracts are cocultured with mouse macrophages. Both qualitative analysis of iNOS\TNF-α and quantitative analysis of IL-6\TNF-α collectively demonstrate the remarkable anti-inflammatory effect of the microspheres. Therefore, the current study presents a novel blood purification treatment of eliminating pathogenic factors and introducing therapeutic factors to stabilize AS plaque.


Assuntos
Resinas Acrílicas , Aterosclerose , Sulfatos de Condroitina , Lipoproteínas LDL , Rosiglitazona , Animais , Camundongos , Lipoproteínas LDL/química , Lipoproteínas LDL/metabolismo , Lipoproteínas LDL/isolamento & purificação , Sulfatos de Condroitina/química , Aterosclerose/tratamento farmacológico , Aterosclerose/metabolismo , Resinas Acrílicas/química , Rosiglitazona/farmacologia , Rosiglitazona/química , Adsorção , Células RAW 264.7 , Microesferas , Ciclodextrinas/química
4.
Chem Soc Rev ; 52(19): 6838-6881, 2023 Oct 02.
Artigo em Inglês | MEDLINE | ID: mdl-37705437

RESUMO

Benefiting from low costs, structural diversities, tunable catalytic activities, feasible modifications, and high stability compared to the natural enzymes, reactive oxygen nanobiocatalysts (RONBCs) have become dominant materials in catalyzing and mediating reactive oxygen species (ROS) for diverse biomedical and biological applications. Decoding the catalytic mechanism and structure-reactivity relationship of RONBCs is critical to guide their future developments. Here, this timely review comprehensively summarizes the recent breakthroughs and future trends in creating and decoding RONBCs. First, the fundamental classification, activity, detection method, and reaction mechanism for biocatalytic ROS generation and elimination have been systematically disclosed. Then, the merits, modulation strategies, structure evolutions, and state-of-art characterisation techniques for designing RONBCs have been briefly outlined. Thereafter, we thoroughly discuss different RONBCs based on the reported major material species, including metal compounds, carbon nanostructures, and organic networks. In particular, we offer particular insights into the coordination microenvironments, bond interactions, reaction pathways, and performance comparisons to disclose the structure-reactivity relationships and mechanisms. In the end, the future challenge and perspectives for RONBCs are also carefully summarised. We envision that this review will provide a comprehensive understanding and guidance for designing ROS-catalytic materials and stimulate the wide utilisation of RONBCs in diverse biomedical and biological applications.

5.
Chem Soc Rev ; 52(20): 7294-7295, 2023 Oct 16.
Artigo em Inglês | MEDLINE | ID: mdl-37753775

RESUMO

Correction for 'Reactive oxygen nanobiocatalysts: activity-mechanism disclosures, catalytic center evolutions, and changing states' by Sujiao Cao et al., Chem. Soc. Rev., 2023, https://doi.org/10.1039/d3cs00087g.

6.
Angew Chem Int Ed Engl ; : e202406427, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38837308

RESUMO

Tuning the interfacial structure of metal oxide substrates is an essential strategy to induce electronic structure reconstruction of supported catalysts, which is of great importance in optimizing their catalytic activities. Herein, vanadium oxides-supported Ir catalysts (Ir-V2O3, Ir-VO2, and Ir-V2O5) with different interfacial bonding environments (Ir-V, Ir-Obri, and Ir-O, respectively) were investigated for hydrogen evolution reaction (HER). The regulating mechanism of the influence of different interfacial bonding environments on HER activity was investigated by both experimental results and computational evidence. Benefiting from the unique advantages of interfacial Ir-V direct metal bonds in Ir-V2O3, including enhanced electron transfer and electron donation ability, an optimized HER performance can be obtained with lowest overpotentials of 16 and 26 mV at 10 mA cm-2, high mass activities of 11.24 and 6.66 A mg-1, and turnover frequency values of 11.20 and 6.63 s-1, in acidic and alkaline conditions respectively. Furthermore, the assembled Ir-V2O3||RuO2 anion exchange membrane (AEM) electrolyzer requires only 1.92 V to achieve a high current density of 500 mA cm-2 and realizes long-term stability. This study provides essential insights into the regulating mechanism of interfacial chemical bonding in electrocatalysts and offers a new pathway to design noble metal catalysts for different applications.

7.
Small ; 19(14): e2206949, 2023 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-36599619

RESUMO

Ruthenium (Ru)-based catalysts have displayed compelling hydrogen evolution activities, which hold the promising potential to substitute platinum in alkaline H2 -evolution. In the challenging alkaline electrolytes, the water-dissociation process involves multistep reactions, while the profound origin and intrinsic factors of diverse Ru species on water-dissociation pathways and reaction principles remain ambiguous. Here the fundamental origin of water-dissociation pathways of Ru-based catalysts in alkaline media to be from their unique electronic structures in complex coordination environments are disclosed. These theoretical results validate that the modulated electronic structures with delocalization-localization coexistence at their boundaries between the Ru nanocluster and single-atom site have a profound influence on water-dissociation pathways, which push H2 O* migration and binding orientation during the splitting process, thus enhancing the dissociation kinetics. By creating Ru catalysts with well-defined nanocluster, single-atom site, and also complex site, the electrocatalytic data shows that both the nanocluster and single-atom play essential roles in water-dissociation, while the complex site possesses synergistically enhanced roles in alkaline electrolytes. This study discloses a new electronic structure-dependent water-dissociation pathway and reaction principle in Ru-based catalysts, thus offering new inspiration to design efficient and durable catalysts for the practical production of H2 in alkaline electrolytes.

8.
Small ; 19(2): e2204738, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36403218

RESUMO

Compared to platinum catalysts, ruthenium (Ru) is disclosed as a promising alternative for alkaline water electrolysis due to its similar hydrogen adsorption energy and relatively lower water dissociation barrier. However, in the challenging alkaline media, the dissatisfied Volmer step during water dissociation of Ru metal prohibits its practical applications. Here, a new pathway to modulate the electronic environment of Ru catalysts via a local charge transfer strategy for tuning the water dissociation kinetics and accelerating the alkaline water electrolysis is proposed. The obtained catalysts are engineered by assembling and subsequently pyrolyzing the layer-stacked and 2D porphyrin-based Ru-N coordination polymers on nanocarbon supports. Benefiting from the well-defined Ru nanocluster-Nx -coordination bonds (Runc -Nx ), unique electronic environments, and local charge transfer properties, the catalysts exhibit the exceptional activity of 17 mV overpotential at 10 mA cm-2 and robust stability in water, which is more efficient than state-of-the-art Ru catalysts. The theoretical calculation suggests that the Runc -Nx sites enhance the nucleophilic attack of water and weaken the HOH bond. This study manifests that tailoring the bond environments of Ru clusters can significantly modulate their intrinsic catalytic activities and stabilities, which may open new avenues for developing high-active and durable catalysts for water electrolysis.


Assuntos
Rutênio , Eletrônica , Adsorção , Eletrólise , Água
9.
Small ; 19(27): e2208261, 2023 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-37012603

RESUMO

The lack of high efficiency and pH-universal bifunctional electrocatalysts for water splitting to hydrogen evolution reaction (HER) and oxygen evolution reaction (OER) hinders the large-scale production of green hydrogen. Here, an IrPd electrocatalyst supported on ketjenblack that exhibits outstanding bifunctional performance for both HER and OER at wide pH conditions is presented. The optimized IrPd catalyst exhibits a specific activity of 4.46 and 3.98 A mgIr -1 in the overpotential of 100 and 370 mV for HER and OER, respectively, in alkaline conditions. When applied to the anion exchange membrane electrolyzer, the Ir44 Pd56 /KB catalyst shows a stability of >20 h at a current of 250 mA cm-2 for water decomposition, indicating promising prospects for practical applications. Beyond offering an advanced electrocatalyst, this work also guides the rational design of desirable bifunctional electrocatalysts for HER and OER by regulating the microenvironments and electronic structures of metal catalytic sites for diverse catalysis.

10.
Biomacromolecules ; 24(5): 2184-2195, 2023 05 08.
Artigo em Inglês | MEDLINE | ID: mdl-37073825

RESUMO

Stem cell therapy is developing rapidly, but existing expansion techniques are insufficient for the use of a large number of cells. The surface chemistry and surface morphology characteristics of materials play a critical role in cellular behaviors and functions and have guiding significance for the design of biomaterials. Many studies have proven that these factors are essential to affect cell adhesion and growth. How to design a suitable biomaterial interface is the focus of recent studies. Here, the mechanosensing of human adipose-derived stem cells (hASC) on a set of materials and materials with various porosity is systematically studied. Guided by the mechanism discoveries, three-dimensional (3D) microparticles with optimized hydrophilicity and morphology are designed via liquid-liquid phase separation technology. The microparticles support scalable stem cell culture and extracellular matrix (ECM) collection, exhibiting great potential for stem cell applications.


Assuntos
Células-Tronco Mesenquimais , Humanos , Materiais Biocompatíveis/metabolismo , Técnicas de Cultura de Células/métodos , Células-Tronco/metabolismo , Técnicas de Cultura de Células em Três Dimensões , Matriz Extracelular/metabolismo , Diferenciação Celular
11.
Biomacromolecules ; 24(9): 4170-4179, 2023 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-37592721

RESUMO

Endotoxin adsorption has received extensive attention in the field of blood purification. However, developing highly efficient endotoxin adsorbents with excellent hemocompatibility remains challenging. In this study, we propose a new approach for developing the functional polyethersulfone (PES) membrane to remove endotoxins. First, the PES polymer is grafted with polyethylene glycol methyl acrylate (PEG-MA) in a homogeneous phase system via γ irradiation, and PES-g-PEG can be directly used to prepare the membrane by the phase inversion method. Then, polydopamine (PDA) is coated as an adhesive layer onto a PES-g-PEG membrane in an alkaline aqueous solution, and lysozyme (Lyz) is covalently immobilized with PDA through the Schiff base reaction. Lysozyme acts as an affinity adsorption ligand of endotoxin through charge and hydrophobic action. Our study reveals that the PEG branched chain and the PDA coating on the PES membrane can maintain the secondary structure of lysozyme, and thus, the immobilized Lyz can maintain high activity. The adsorption capacity of endotoxins for the PES-g-PEG/PDA/Lyz membrane is 1.28 EU/mg, with an equilibrium adsorption time of 6 h. Therefore, the PES-g-PEG/PDA/Lyz membrane shows great potential application in the treatment of endotoxemia.


Assuntos
Endotoxinas , Muramidase , Sulfonas , Polietilenoglicóis
12.
Environ Res ; 237(Pt 1): 116781, 2023 Nov 15.
Artigo em Inglês | MEDLINE | ID: mdl-37517488

RESUMO

Soil microorganisms and N cycling are important components of biogeochemical cycling processes. In addition, the study of the effects of nitrification and urease inhibitors on N and microorganisms in greenhouse vegetable fields is essential to reducing N loss and greenhouse gas emissions. The effects of nitrification inhibitors [2-chloro-6-(trichloromethyl) pyridine (CP), dicyandiamide (DCD)], and urease inhibitor [N-(n-butyl) thiophosphoric triamide (NBPT)] on soil inorganic N (NH4+-N, NO2--N and NO3--N) concentrations and the production rates of greenhouse gases (N2O, CH4, and CO2) in greenhouse vegetable fields were investigated via indoor incubation experiments. Polymerase chain reaction amplification and high-throughput sequencing technology (Illumina Miseq) were used to explore the community structure and abundance changes of ammonia-oxidizing archaea (AOA), ammonia-oxidizing bacteria (AOB), and denitrifying bacteria (nirK and nirS). The results showed that CP and DCD obviously inhibited NH4+-N conversion, and NO2--N, and NO3--N accumulation, NBPT slowed down urea hydrolysis and NH4+-N production, and the apparent nitrification rates of soil were in the following order: NBPT > DCD > DCD + NBPT > CP + NBPT > CP. Compared with urea treatment, the peak N2O production rate of inhibitor treatment decreased by 73.30-99.30%, and the production rate of CH4 and CO2 decreased by more than 66.16%. DCD and CP reduced the abundance of AOA and AOB, respectively. Furthermore, NBPT hindered the growth of ammonia-oxidizing microorganisms and nirS-type denitrifying bacteria, and urea and nitrification inhibitors were detrimental to the growth of Ensifer and Sinorhizobium in the nirK community. Nitrification and urease inhibitors can effectively slow down nitrification and greenhouse gas emissions, reduce N loss and improve soil quality by inhibiting the growth of ammonia-oxidizing microorganisms and denitrifying bacteria.

13.
Environ Geochem Health ; 45(5): 2013-2030, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-35764757

RESUMO

To understand the characteristics, temporal and spatial variation, and health risks of atmospheric heavy metal pollution in different areas of the YRD (Yellow River Delta), atmospheric particles samples were collected in the YRD in China during 2016-2017. A total of 10 monitoring points were chosen in different areas (industrial parks, main urban areas, and rural areas) in the YRD, heavy metals were monitored using atomic fluorescence spectrometry and graphite furnace atomic absorption spectrometry. The results showed that TSP (total suspended particulate), PM10 (particulate matter with an aerodynamic diameter less than 10 µm), and PM2.5 (particulate matter with an aerodynamic diameter less than 2.5 µm) contents were higher in the Kenli EDZ (economic development zone) and Kenli urban areas than those in other points. The concentration range of heavy metals in atmospheric samples at 10 points was different, with a difference of five orders of magnitude, of which the content of copper (Cu) was the highest, with the highest concentration of 4.375 µg/m3, and the content of particulate mercury (Hg) was the lowest, with the minimum concentration of 0.00001 µg/m3. Among the nine heavy metals, the contents of cadmium (Cd), lead (Pb), and Hg were higher in winter than in summer, and chromium (Cr), nickel (Ni), Cu, and manganese (Mn) were higher in summer than in winter. In addition to Hg, the contents of the other eight heavy metals in particulate matter showed a trend that urban areas and EDZs had higher concentrations than cities and towns and nature reserves, which can be attributed to industrial activities and coal-fired fuel emissions. Health risk assessment was carried out for adults and children, respectively, and the results showed that carcinogens have no obvious carcinogenic risk, but As and Cr have major potential carcinogenic risk. Among the noncarcinogenic substances, Mn has the greatest noncarcinogenic risk, and urban areas and economic development zones have the greatest risk. This study investigated the characteristics and health risk assessment of atmospheric heavy metal pollution in different areas in the YRD to supplement the research contents of atmospheric particulate heavy metals in the YRD in domestics and overseas. It is also critical to study the pollution and migration of heavy metals in China.


Assuntos
Mercúrio , Metais Pesados , Criança , Adulto , Humanos , Material Particulado/análise , Rios , Monitoramento Ambiental/métodos , Metais Pesados/análise , Poeira/análise , China , Mercúrio/análise , Cromo/análise , Manganês/análise , Medição de Risco , Carvão Mineral/análise
14.
Small ; 18(17): e2105831, 2022 04.
Artigo em Inglês | MEDLINE | ID: mdl-35102688

RESUMO

Currently, the development of advanced 2D nanomaterials has become an interdisciplinary subject with extensive studies due to their extraordinary physicochemical performances. Beyond graphene, the emerging 2D-material-derived electrocatalysts (2D-ECs) have aroused great attention as one of the best candidates for heterogeneous electrocatalysis. The tunable physicochemical compositions and characteristics of 2D-ECs enable rational structural engineering at the molecular/atomic levels to meet the requirements of different catalytic applications. Due to the lack of instructive and comprehensive reviews, here, the most recent advances in the nanostructure and catalytic center design and the corresponding structure-function relationships of emerging 2D-ECs are systematically summarized. First, the synthetic pathways and state-of-the-art strategies in the multifaceted structural engineering and catalytic center design of 2D-ECs to promote their electrocatalytic activities, such as size and thickness, phase and strain engineering, heterojunctions, heteroatom doping, and defect engineering, are emphasized. Then, the representative applications of 2D-ECs in electrocatalytic fields are depicted and summarized in detail. Finally, the current breakthroughs and primary challenges are highlighted and future directions to guide the perspectives for developing 2D-ECs as highly efficient electrocatalytic nanoplatforms are clarified. This review provides a comprehensive understanding to engineer 2D-ECs and may inspire many novel attempts and new catalytic applications across broad fields.


Assuntos
Grafite , Nanoestruturas , Catálise , Nanoestruturas/química
15.
Small ; 18(2): e2104328, 2022 01.
Artigo em Inglês | MEDLINE | ID: mdl-34738726

RESUMO

Cell polarization exists in a variety of tissues to regulate cell behaviors and functions. Space constraint (spatially limiting cell extension) and adhesion induction (guiding adhesome growth) are two main ways to induce cell polarization according to the microenvironment topographies. However, the mechanism of cell polarization induced by these two ways and the downstream effects on cell functions are yet to be understood. Here, space constraint and adhesion induction guiding cell polarization are achieved by substrate groove arrays in micro and nano size, respectively. Although the morphology of polarized cells is similar on both structures, the signaling pathways to induce the cell polarization and the downstream functions are distinctly different. The adhesion induction (nano-groove) leads to the formation of focal adhesions and activates the RhoA/ROCK pathway to enhance the myosin-based intracellular force, while the space constraint (micro-groove) only activates the formation of pseudopodia. The enhanced intracellular force caused by adhesion induction inhibits the chromatin condensation, which promotes the osteogenic differentiation of stem cells. This study presents an overview of cell polarization and mechanosensing at biointerface to aid in the design of novel biomaterials.


Assuntos
Sinais (Psicologia) , Osteogênese , Adesão Celular , Diferenciação Celular , Adesões Focais/metabolismo
16.
Biomacromolecules ; 23(9): 3728-3742, 2022 09 12.
Artigo em Inglês | MEDLINE | ID: mdl-35926229

RESUMO

Hemoperfusion is an important method to remove endotoxins and save the lives of patients with sepsis. However, the current adsorbents for hemoperfusion have disadvantages of insufficient endotoxin adsorption capacity, poor blood compatibility, and so on. Herein, we proposed a novel emulsion templating (ET) method to prepare ultraporous and double-network carboxylated chitosan (CCS)-poly(diallyl dimethylammonium chloride) (PDDA) hydrogel spheres (ET-CCSPD), bearing both negative and positive charges. CCS was introduced to balance the strong positive charges of PDDA to improve hemocompatibility, and emulsion templates endowed the adsorbent with an ultraporous structure for enhanced adsorption efficacy. The ET-CCSPDs neither damaged blood cells nor activated complement responses. In addition, the activated partial thromboplastin time (APTT) was prolonged to 8.5 times, which was beneficial for reducing the injection of anticoagulant in patients. The ET-CCSPDs had excellent scavenging performance against bacteria and endotoxin, with removal ratios of 96.7% for E. coli and 99.8% for S. aureus, respectively, and the static removal ratio of endotoxin in plasma was as high as 99.1% (C0 = 5.50 EU/mL, critical illness level). An adsorption cartridge filled with the ET-CCSPDs could remove 84.7% of endotoxin within 1 h (C0 = 100 EU/mL in PBS). Interestingly, the ET-CCSPDs had a good inhibitory effect on the cytokines produced by endotoxin-mediated septic blood. By developing the ET method to prepare ultraporous and double-network adsorbents, the problems of low adsorption efficiency and poor blood compatibility of traditional endotoxin adsorbents have been solved, thus opening a new route to fabricate absorbents for blood purification.


Assuntos
Quitosana , Sepse , Adsorção , Antibacterianos , Anticoagulantes/farmacologia , Emulsões , Endotoxinas , Escherichia coli , Humanos , Hidrogéis/farmacologia , Sepse/tratamento farmacológico , Staphylococcus aureus
17.
Biomacromolecules ; 23(3): 889-902, 2022 03 14.
Artigo em Inglês | MEDLINE | ID: mdl-35090105

RESUMO

Burn injury has become a crucial public health issue worldwide. It is necessary to explore new methods to reduce heat damage and improve healing efficiency during burn injury treatment. In this study, a kind of hydrogel combining heat storage capacity and thermal conductivity was fabricated via a one-pot method for burn therapy. The novel hydrogel was easily prepared by in situ cross-linking polymerization, using poly(ethylene glycol) (PEG) derivatives, oligo(ethylene glycol) methacrylate and 2-(2-methoxyethoxy) ethyl methacrylate, as thermally responsive base materials and hydroxylated multiwall carbon nanotubes (CNT-OH) as thermally conductive fillers. By dispersing CNT-OH, a thermally conductive network was formed in the hydrogel, leading to an increase in the thermal conductivity. The cooling performance, thermal conductivity, heat storage property, swelling performance, rheological and mechanical properties, biocompatibility, in vivo cooling effect, and wound healing properties of the prepared hydrogel were systematically investigated. The hydrogel consisted of thermally responsive PEG derivatives, and CNT-OH performed a function of rapid heat absorption, further reduced thermal damage, and promoted wound healing. The improved cooling performance of the hydrogel was ascribed to the improved thermal conductivity, enhanced heat storage capacity, and good adhesive ability. Thus, the hydrogel has great potential to be practically applied in burn therapy, laser treatment, cooling fabrics, heat-protective clothing, and other emergency scenarios.


Assuntos
Queimaduras , Nanotubos de Carbono , Bandagens , Queimaduras/terapia , Temperatura Alta , Humanos , Hidrogéis , Metacrilatos , Condutividade Térmica
18.
Soft Matter ; 18(17): 3308-3312, 2022 May 04.
Artigo em Inglês | MEDLINE | ID: mdl-35416827

RESUMO

Herein, an ultrastable and reusable stomatocyte nanomotor using a photo-crosslinkable block copolymer is presented. After photo-crosslinking, the resulting nanomotors equipped with a covalently crosslinked membrane, are able to withstand the destruction of organic solvents, resist the corrosion of strong acidic and alkali solutions, and repeatedly move many times.

19.
Fish Shellfish Immunol ; 130: 501-511, 2022 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-36162773

RESUMO

Liza haematocheila is exposed to various chemical contaminants from anthropogenic sources, including tributyltin chloride (TBTC). Yet the toxicity mechanism of TBTC on haarder remains unclear. The haarder was exposed to different doses (0, 10%, 20%, and 50% of LC50-96 h) of TBTC. In this study, the results revealed its high bioaccumulation in the livers and significant alteration for development. The activities of antioxidant enzymes superoxide dismutase, catalase, and glutathione peroxidase decreased after 96-h exposure to TBTC, this accompanied by an increased malondialdehyde level. TBTC exposure caused the intense production of reactive oxygen species, a reduction in total blood cell count in serum, and apoptosis-related alterations in livers, indicating that enhanced oxidative stress occurred in the process of TBTC exposure. Histological results revealed angiorrhexis and infiltration of inflammatory cells, vacuolar degeneration of hepatocytes in the livers, and swelling, fusion, and disintegration of gill organs. Interestingly, the obtained transcriptional profiles indicated that high doses of TBTC caused energy disorder, apoptosis, and adipogenesis restriction mediated by cytokines and adipokines in Jak-STAT and adipocytokine signaling pathways. In summary, acute exposure to high doses of TBTC could impair the antioxidant system and pathways related to energy, apoptosis and adipogenesis, eventually posing a serious challenge to the fitness of haarder individuals and its fish populations as marine resources.


Assuntos
Antioxidantes , Estresse Oxidativo , Adipocinas/metabolismo , Animais , Antioxidantes/metabolismo , Bioacumulação , Catalase/metabolismo , Citocinas/metabolismo , Glutationa Peroxidase/metabolismo , Malondialdeído , Espécies Reativas de Oxigênio/metabolismo , Superóxido Dismutase/metabolismo , Compostos de Trialquitina
20.
Angew Chem Int Ed Engl ; 61(13): e202115331, 2022 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-34936185

RESUMO

Developing low-cost electrocatalysts for efficient and robust oxygen evolution reaction (OER) is the key for scalable water electrolysis, for instance, NiFe-based materials. Decorating NiFe catalysts with other transition metals offers a new path to boost their catalytic activities but often suffers from the low controllability of the electronic structures of the NiFe catalytic centers. Here, we report an interfacial atom-substitution strategy to synthesize an electrocatalytic oxygen-evolving NiFeV nanofiber to boost the activity of NiFe centers. The electronic structure analyses suggest that the NiFeV nanofiber exhibits abundant high-valence Fe via a charge transfer from Fe to V. The NiFeV nanofiber supported on a carbon cloth shows a low overpotential of 181 mV at 10 mA cm-2 , along with long-term stability (>20 h) at 100 mA cm-2 . The reported substitutional growth strategy offers an effective and new pathway for the design of efficient and durable non-noble metal-based OER catalysts.

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