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Ion-selective membrane has broad application in various fields, while the present solution-processed techniques can only prepare uniform membrane with microscale thickness. Herein, a high-quality polymer membrane with nanoscale thickness and uniformity is precisely prepared by controlling solution spreading and solvent evaporation stability/rate. With the arrayed capillaries, the stable spreading of polymer solution with volume of microliter induces the formation of solution film with micrometers thickness. Moreover, the fast increase of solution dynamic viscosity during solvent evaporation inhibits nonuniform Marangoni flow and capillary flow in solution film. Consequently, the uniform Nafion-Li membranes with â¼200 nm thickness are prepared, while their Li+ conductivity is 2 orders of magnitude higher than that of commercially Nafion-117 membrane. Taking lithium-sulfur battery as a model device, the cells (capacities of 8-10 mAh cm-2) can stably operate for 150 cycles at a S loading of 12 mg cm-2 and an electrolyte/sulfur ratio of â¼7.
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Li metal is regarded as the "Holy Grail" in the next generation of anode materials due to its high theoretical capacity and low redox potential. However, sluggish Li ions interfacial transport kinetics and uncontrollable Li dendrites growth limit practical application of the energy storage system in high-power device. Herein, separators are modified by the addition of a coating, which spontaneously grafts onto the Li anode interface for in situ lithiation. The resultant alloy possessing of strong electron-donating property promotes the decomposition of lithium bistrifluoromethane sulfonimide in the electrolyte to form a LiF-rich alloy-doped solid electrolyte interface (SEI) layer. High ionic alloy solid solution diffusivity and electric field dispersion modulation accelerate Li ions transport and uniform stripping/plating, resulting in a high-power dendrite-free Li metal anode interface. Surprisingly, the formulated SEI layer achieves an ultra-long cycle life of over 8000â h (20,000â cycles) for symmetric cells at a current density of 10â mA cm-2. It also ensures that the NCM(811)//PP@Au//Li full cell at ultra-high currents (40â C) completes the charging/discharging process in only 68â s to provide high capacity of 151â mAh g-1. The results confirm that this scalable strategy has great development potential in realizing high power dendrite-free Li metal anode.
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Replacing electrocatalytic oxygen evolution reaction (OER) with amine oxidation reaction is adopted to boost clean and environment-friendly energy source hydrogen (H2 ) in water. However, the electrocatalytic reaction is severely restricted by the strong adsorption of product on the catalyst surface. Inspired by the cooperation of flavin adenine dinucleotide and mitochondria membrane in biological system, the catalysis-separation complex electrodes are introduced to promote the desorption of product and hinder its readsorption by applying polytetrafluoroethylene (PTFE)-separation membrane on the one side of electrode, which is benefit for the cleanness of active sites on the catalyst surface for the continuous production and timely separation of nitrile and hydrogen. With the intermolecular force between PTFE and nitrile, the nitrile droplets can be quickly desorbed and separated from catalyst surface of anode, and the size of nitrile droplets on the catalyst surface is only 0.23% to that without PTFE. As a result, the current at 1.49 VRHE from the catalyst with PTFE membrane is about 33 times to that of catalyst without PTFE after long-term operation. Moreover, the cathode with PTFE membrane also achieves the rapid desorption of H2 bubbles and stable cathodic current because of the strong absorption of PTFE to H2 .
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Sonodynamic therapy (SDT) triggered by ultrasound (US) has attracted increasing attention owing to its ability to overcome critical limitations, including low tissue-penetration depth and phototoxicity in photodynamic therapy (PDT). Biogenic metal oxide nanoparticles (NPs) have been used as anti-cancer drugs due to their biocompatibility properties with most biological systems. Here, sonosensitizer MWO4-PEG NPs (M = Fe Mn Co Ni) were synthesized as inhibitors to activation-induced cytidine deaminase (AID), thus neutralizing the extensive carcinogenesis of AID in diffuse large B-cell lymphoma (DLBCL). The physiological properties of these nanomaterials were examined using transmission electron microscopy (TEM). The inhibition of NPs to AID was primarily identified by the affinity interaction prediction between reactive oxygen species (ROS) and AID through molecular dynamics and molecular docking technology. The cell apoptosis and ROS generation in US-triggered NPs treated DLBCL cells (with high levels of AID) were also detected to indicate the sonosensitivity and toxicity of MWO4-PEG NPs to DLBCL cells. The anti-lymphoma studies using DLBCL and AID-deficient DLBCL cell lines indicated a concentration-dependent profile. The synthesized MWO4-PEG NPs in this study manifested good sonodynamic inhibitory effects to AID and well treatment for AID-positive hematopoietic cancers.
Assuntos
Linfoma Difuso de Grandes Células B , Nanopartículas Metálicas , Nanopartículas , Terapia por Ultrassom , Humanos , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Simulação de Acoplamento Molecular , Linfoma Difuso de Grandes Células B/tratamento farmacológico , Linfoma Difuso de Grandes Células B/metabolismo , Linfoma Difuso de Grandes Células B/patologia , Óxidos , Polietilenoglicóis/uso terapêuticoRESUMO
Lithium-sulfur (Li-S) batteries have potential in high energy density battery systems. However, intermediates of lithium polysulfides (LiPSs) can easily shuttle to the Li anode and react with Li metal to deplete the active materials and cause rapid failure of the battery. A facile solution pretreatment method for Li anodes involving a solution of metal fluorides/dimethylsulfoxide was developed to construct robust biphasic surface layers (BSLs) inâ situ. The BSLs consist of lithiophilic alloy (Lix M) and LiF phases on Li metal, which inhibit the shuttle effect and increase the cycle life of Li-S batteries. The BSLs allow Li+ transport and they inhibit dendrite growth and shield the Li anodes from corrosive reaction with LiPSs. Li-S batteries containing BSLs-Li anodes demonstrate excellent cycling over 1000â cycles at 1â C and simultaneously maintain a high coulombic efficiency of 98.2 %. Based on our experimental and theoretical results, we propose a strategy for inhibition of the shuttle effect that produces high stability Li-S batteries.
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Sonodynamic therapy (SDT) has attracted great attention due to its deep tissue penetration, uniform tissue energy distribution, and noninvasiveness features. Additionally, external triggers can precisely focus on the tumor site with good specificity and high controllability. In the past decade, numerous sonosensitizers have been designed and used for SDT. However, the research and development of universal sonosensitizers for many different types of tumors are equally important in clinical treatment. Herein, we synthesized and studied the universality of four MWO4-PEG nanoparticles (NPs). All of the four MWO4-PEG NPs exhibited highly efficient ultrasound (US)-triggered production of 1O2 and ËOH, enabling effective decreased cell viability, increased cell apoptosis rate, and a destruction of mouse tumors under US stimulation. The US-triggered NPs indicated good sonosensitivity and low toxicity to nine kinds of cancer cells. After accomplishing its therapeutic functions, NiWO4-PEG could be metabolized by the mouse body without any long-term toxicity. The PEGylated MWO4-PEG NPs shown in this study would provide efficient and universal US-triggered cancer therapy with the advantages of a cost-effective, convenient, and noninvasive agent that is promising for noninvasive SDT cancer treatment.
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Nanopartículas , Neoplasias , Terapia por Ultrassom , Camundongos , Animais , Espécies Reativas de Oxigênio/metabolismo , Linhagem Celular Tumoral , Ultrassonografia , Nanopartículas/metabolismo , Neoplasias/tratamento farmacológicoRESUMO
Lung metastatic breast cancer (LMBC) leads to a large number of deaths in women with breast cancer, and radiotherapy has been considered the common assay for tumour therapy except for surgery. However, radiotherapy still faces problems of low efficiency due to resistance and easily induced side effects. Here, the authors designed lipid-decorated bismuth-based nanoflowers (DP-BNFs) as both a radiosensitiser and a photothermal therapy agent for LMBC treatment. The BNFs were prepared by oxidation of bismuth nitrate and subsequent reduction using sodium borohydride. The preparation parameters and formulation of DP-BNFs were optimised via a single-factor experiment, with the factors including reaction temperature, a molar ratio of reducing agents, and the types and amount of decorated lipid materials. The result indicated that the BNFs prepared at 170°C with the Bi/NaBH4 ratio of 1:0.7 exhibited the best yield and particle size around 160 nm. After being spray dried with lactose to prepare dry powder inhalation (DP-BNF@Lat-MPs), their effects on improving therapeutic efficiency of the radiotherapy and photothermal therapy combination were measured using the western blot assay to determine the tumour apoptosis. In a word, DP-BNF@Lat-MPs could be a novel inhalable integrated microsphere that provides a new possibility for thermoradiotherapy of LMBC.
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Neoplasias da Mama , Neoplasias Pulmonares , Feminino , Humanos , Neoplasias da Mama/tratamento farmacológico , Bismuto , Tamanho da Partícula , Pós , Neoplasias Pulmonares/tratamento farmacológico , Pulmão , LipídeosRESUMO
Biothiols are widely involved in various important physiological activities and play a significant role in maintaining redox homeostasis in living organisms. Herein, we designed and synthesized three new asymmetric fluorescent probes (BDP-S-Ph, BDP-S-ENE and BDP-S-R) to discriminate Cys from Hcy/GSH. These probes reacted with Cys to form meso-amino-BODIPYs via SNAr substitution-rearrangement, thereby inducing a fluorescence turn-on effect. Moreover, they could selectively and sensitively detect Cys in solution with low detection limits (50 nM, 28 nM and 87 nM, respectively). Through comparing the response rates of the three probes to Cys, we concluded that the increase of conformational restrictions led to a decrease in probe reactivity. Besides, the sensing mechanism was demonstrated by mass spectrometry. Furthermore, cell experiments indicated that the probes were able to image exogenous and endogenous Cys through green or red channels in living cells.
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Cisteína , Corantes Fluorescentes , Compostos de Boro , GlutationaRESUMO
Velcro, the most typical hook-loop interlocker, often suffers from undesirable deformation, breaking, and noise because of the structure of the hook. Inspired by the arrester system of dragonfly, a new mechanical interlocker with a nylon pestle instead of the traditional hook is developed. The pestle-loop mechanical interlocker shows a tunable peeling force from 0.4 ± 0.14 to 6.5 ± 0.72 N and the shear adhesion force of pestle-loop mechanical interlocker is about twice as much as that of velcro. The pestle tape can be separated and fastened with the loop tape up to 30 000 cycles while keeping the original adhesive force and the pestle structure. In comparison, only after 4000 cycles most hooks of the commercial velcro are deformed and even broken, completely losing their adhesive function and their hook structure. These experimental results are further supported by finite element simulitions-the base of pestle mainly bears the separation-caused strain while the middle of hook does. Notably, the sound volume during the separation of pestle-loop mechanical interlocker is merely 49 ± 7.4 dB, much lower than 70 ± 3.5 dB produced by the velcro.