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1.
Curr Opin Oncol ; 36(2): 102-114, 2024 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-38441046

RESUMO

PURPOSE OF REVIEW: In this review, we summarized published articles on the role of tripartite motif (TRIM) family members in the initiation and development of human malignancies. RECENT FINDINGS: The ubiquitin-proteasome system (UP-S) plays a critical role in cellular activities, and UP-S dysregulation contributes to tumorigenesis. One of the key regulators of the UP-S is the tripartite motif TRIM protein family, most of which are active E3 ubiquitin ligases. TRIM proteins are critical for the biological functions of cancer cells, including migration, invasion, metastasis, and therapy resistance. Therefore, it is important to understand how TRIM proteins function at the molecular level in cancer cells. SUMMARY: We provide a comprehensive and up-to-date overview about the role TRIMs play in cancer progression and therapy resistance. We propose TRIM family members as potential new markers and targets to overcome therapy failure.


Assuntos
Carcinogênese , Transformação Celular Neoplásica , Humanos , Proteínas com Motivo Tripartido , Ubiquitinas
2.
Small ; 20(16): e2307579, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38044290

RESUMO

The design and fabrication of novel carbon hosts with high conductivity, accelerated electrochemical catalytic activities, and superior physical/chemical confinement on sulfur and its reaction intermediates polysulfides are essential for the construction of high-performance C/S cathodes for lithium-sulfur batteries (LSBs). In this work, a novel biofermentation coupled gel composite assembly technology is developed to prepare cross-linked carbon composite hosts consisting of conductive Rhizopus hyphae carbon fiber (RHCF) skeleton and lamellar sodium alginate carbon (SAC) uniformly implanted with polarized nanoparticles (V2O3, Ag, Co, etc.) with diameters of several nanometers. Impressively, the RHCF/SAC/V2O3 composites exhibit enhanced physical/chemical adsorption of polysulfides due to the synergistic effect between hierarchical pore structures, heteroatoms (N, P) doping, and polar V2O3 generation. Additionally, the catalytic conversion kinetics of cathodes are effectively improved by regulating the 3D carbon structure and optimizing the V2O3 catalyst. Consequently, the LSBs assembled with RHCF/SAC/V2O3-S cathode show exceptional cycle stability (capacity retention rate of 94.0% after 200 cycles at 0.1 C) and excellent rate performance (specific capacity of 578 mA h g-1 at 5 C). This work opens a new door for the fabrication of hyphae carbon composites via fermentation for electrochemical energy storage.

3.
Small ; 20(15): e2306381, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38013253

RESUMO

All-solid-state lithium metal batteries (LMBs) are regarded as one of the most viable energy storage devices and their comprehensive properties are mainly controlled by solid electrolytes and interface compatibility. This work proposes an advanced poly(vinylidene fluoride-hexafluoropropylene) based gel polymer electrolyte (AP-GPEs) via functional superposition strategy, which involves incorporating butyl acrylate and polyethylene glycol diacrylate as elastic optimization framework, triethyl phosphate and fluoroethylene carbonate as flameproof liquid plasticizers, and Li7La3Zr2O12 nanowires (LLZO-w) as ion-conductive fillers, endowing the designed AP-GPEs/LLZO-w membrane with high mechanical strength, excellent flexibility, low flammability, low activation energy (0.137 eV), and improved ionic conductivity (0.42 × 10-3 S cm-1 at 20 °C) due to continuous ionic transport pathways. Additionally, the AP-GPEs/LLZO-w membrane shows good safety and chemical/electrochemical compatibility with the lithium anode, owing to the synergistic effect of LLZO-w filler, flexible frameworks, and flame retardants. Consequently, the LiFePO4/Li batteries assembled with AP-GPEs/LLZO-w electrolyte exhibit enhanced cycling performance (87.3% capacity retention after 600 cycles at 1 C) and notable high-rate capacity (93.3 mAh g-1 at 5 C). This work proposes a novel functional superposition strategy for the synthesis of high-performance comprehensive GPEs for LMBs.

4.
Small ; : e2401491, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38751305

RESUMO

The design and fabrication of a lithiophilic skeleton are highly important for constructing advanced Li metal anodes. In this work, a new lithiophilic skeleton is reported by planting metal sulfides (e.g., Ni3S2) on vertical graphene (VG) via a facile ultrafast Joule heating (UJH) method, which facilitates the homogeneous distribution of lithiophilic sites on carbon cloth (CC) supported VG substrate with firm bonding. Ni3S2 nanoparticles are homogeneously anchored on the optimized skeleton as CC/VG@Ni3S2, which ensures high conductivity and uniform deposition of Li metal with non-dendrites. By means of systematic electrochemical characterizations, the symmetric cells coupled with CC/VG@Ni3S2 deliver a steady long-term cycle within 14 mV overpotential for 1800 h (900 cycles) at 1 mA cm-2 and 1 mAh cm-2. Meanwhile, the designed CC/VG@Ni3S2-Li||LFP full cell shows notable electrochemical performance with a capacity retention of 92.44% at 0.5 C after 500 cycles and exceptional rate performance. This novel synthesis strategy for metal sulfides on hierarchical carbon-based materials sheds new light on the development of high-performance lithium metal batteries (LMBs).

5.
Opt Express ; 32(11): 19999-20010, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38859119

RESUMO

Goos-Hänchen shift of total internal reflection (TIR) is the light beam movement without external driving, so envisioned to have potential manipulation of optical beams. In this article, with a silicon-on-insulator (SOI) waveguide corner structure, a variable equivalent permittivity of guided wave is modelled, and then the equivalent electric polarizabilities and the Goos-Hänchen shift of guided wave are modelled. Consequently, with a 2.0-µm SOI waveguide corner structure and an abrupt phase change of ∼0.5π caused by a vertically inserted metasurface of nanoscale semi-spheres having a 450-nm radius can reach the GH shifts of 2.1 µm for TE- and TM-mode, respectively, which are verified by both the FDTD simulation results of 1.93 µm with a reflectivity of about 62% and the experimental results of 2.0 µm with ∼60%. Therefore, this work has efficiently modelled the optical feature response of semi-sphere metasurface to guided wave and the active manipulation for the GH shifts of guided-wave, opening more opportunities to develop the new functionalities and devices for Si-based photonic integrated circuit (PIC) applications.

6.
Chemistry ; 30(19): e202304168, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38264940

RESUMO

"Carbon Peak and Carbon Neutrality" is an important strategic goal for the sustainable development of human society. Typically, a key means to achieve these goals is through electrochemical energy storage technologies and materials. In this context, the rational synthesis and modification of battery materials through new technologies play critical roles. Plasma technology, based on the principles of free radical chemistry, is considered a promising alternative for the construction of advanced battery materials due to its inherent advantages such as superior versatility, high reactivity, excellent conformal properties, low consumption and environmental friendliness. In this perspective paper, we discuss the working principle of plasma and its applied research on battery materials based on plasma conversion, deposition, etching, doping, etc. Furthermore, the new application directions of multiphase plasma associated with solid, liquid and gas sources are proposed and their application examples for batteries (e. g. lithium-ion batteries, lithium-sulfur batteries, zinc-air batteries) are given. Finally, the current challenges and future development trends of plasma technology are briefly summarized to provide guidance for the next generation of energy technologies.

7.
Nano Lett ; 23(17): 8319-8325, 2023 Sep 13.
Artigo em Inglês | MEDLINE | ID: mdl-37643363

RESUMO

Although the topological band theory is applicable to both Fermionic and bosonic systems, the same electronic and phononic topological phases are seldom reported in one natural material. In this work, we show the presence of a dual-higher-order topology in hydrogen-substituted graphdiyne (H-GDY) by first-principles calculations. The intriguing enantiomorphic flat-bands are realized in both electronic and phononic bands of H-GDY, which is confirmed to be an organic 2D second-order topological insulator (SOTI). Most importantly, we found that the topological corner states are pseudospin polarized in H-GDY, exhibiting a clockwise or counterclockwise texture perpendicular to the radial direction. Our results not only identify the existence of the dual-higher-order topology in covalent organic frameworks but also uncover a unique pseudospin polarization-coordinate locking relation, further extending the well-known spin-momentum locking relation in conventional topological insulators.

8.
Small ; 19(24): e2208164, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36916700

RESUMO

Solid-state lithium-sulfur batteries (SSLSBs) have attracted tremendous research interest due to their large theoretical energy density and high safety, which are highly important indicators for the development of next-generation energy storage devices. Particularly, safety and "shuttle effect" issues originating from volatile and flammable liquid organic electrolytes can be fully mitigated by switching to a solid-state configuration. However, their road to thecommercial application is still plagued with numerous challenges, most notably the intrinsic electrochemical instability of solid-state electrolytes (SSEs) materials and their interfacial compatibility with electrodes and electrolytes. In this review, a critical discussion on the key issues and problems of different types of SSEs as well as the corresponding optimization strategies are first highlighted. Then, the state-of-the-art preparation methods and properties of different kinds of SSE materials, and their manufacture, characterization and performance in SSLSBs are summarized in detail. Finally, a scientific outlook for the future development of SSEs and the avenue to commercial application of SSLSBs is also proposed.

9.
Phys Chem Chem Phys ; 25(34): 22920-22926, 2023 Aug 30.
Artigo em Inglês | MEDLINE | ID: mdl-37591826

RESUMO

Na3PS4 crystals with high ionic conductivity are promising solid-state electrolytes. Here, a novel phase of Na3PS4 (ß'-NPS) crystallizing in a cubic lattice with a space group of P4̄3m was systematically investigated using first-principles calculations. First of all, ß'-NPS is determined to be thermodynamically, dynamically and mechanically stable. The phase transition from tetragonal Na3PS4(α-NPS) to a cubic ß'-NPS system occurs at approximately 480 K, suggesting high feasibility of experimental access. Moreover, the ß'-NPS is an insulator with a large band gap of 4.05 eV and a low migration energy barrier of 0.10 eV for an interstitial Na ion. Significantly, a novel Na ion diffusion mechanism, that is, interstitial diffusion, is proposed, in contrast to traditional vacancy diffusion or kick-off diffusion as observed in most solid electrolytes. This work proposes ß'-NPS as a promising superionic conductor for sodium ion batteries and provides theoretical guidance towards designing future ideal solid-state electrolytes.

10.
J Phys Chem A ; 127(42): 8935-8942, 2023 Oct 26.
Artigo em Inglês | MEDLINE | ID: mdl-37844321

RESUMO

NH2SO3H is an effective nucleation agent for the formation of atmospheric aerosols and cloud particles. So, the ammonolysis of SO3 to form NH2SO3H without and with neutral (H2O) and basic (NH3) trace gases has been extensively investigated. However, the acidic trace gas X (X = H2SO4 and CH3SO3H)-assisted ammonolysis of SO3 is still up for debate. In this work, a comprehensive theoretical investigation of X-assisted ammonolysis of SO3 and its reverse reaction (the isomerization of NH2SO3H to form SO3-···NH3+) was carried out in the gas phase and at the air-water interface. The gas-phase results show that X-assisted isomerization of NH2SO3H to form SO3-···NH3+ is more energetically and kinetically favorable than its reverse reaction and the isomerization of NH2SO3H in the presence of H2O and NH3. Such unexpected findings revealed that gas-phase NH2SO3H is highly reactive in the presence of acidic trace gas in contrast to the high stability of NH2SO3H in neutral and basic conditions. At the air-water interface, the X-assisted isomerization reaction of NH2SO3H involves multiple water molecules. The loop structure of the reaction center (X···NH2SO3H···3H2O) promotes the transfer of protons in the water molecules to form the SO3-···NH3+ ion pair, which can then interact with several interfacial water molecules to form ammonium bisulfate. These interfacial reaction channels follow a stepwise mechanism and proceed at the picosecond time-scale. The findings of this study will contribute to a better understanding of the atmospheric behavior of NH2SO3H in polluted acidic trace gases.

11.
J Environ Sci (China) ; 127: 308-319, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36522063

RESUMO

Given the high abundance of water in the atmosphere, the reaction of Criegee intermediates (CIs) with (H2O)2 is considered to be the predominant removal pathway for CIs. However, recent experimental findings reported that the reactions of CIs with organic acids and carbonyls are faster than expected. At the same time, the interface behavior between CIs and carbonyls has not been reported so far. Here, the gas-phase and air-water interface behavior between Criegee intermediates and HCHO were explored by adopting high-level quantum chemical calculations and Born-Oppenheimer molecular dynamics (BOMD) simulations. Quantum chemical calculations evidence that the gas-phase reactions of CIs + HCHO are submerged energy or low energy barriers processes. The rate ratios speculate that the HCHO could be not only a significant tropospheric scavenger of CIs, but also an inhibitor in the oxidizing ability of CIs on SOx in dry and highly polluted areas with abundant HCHO concentration. The reactions of CH2OO with HCHO at the droplet's surface follow a loop structure mechanism to produce i) SOZ (), ii) BHMP (HOCH2OOCH2OH), and iii) HMHP (HOCH2OOH). Considering the harsh reaction conditions between CIs and HCHO at the interface (i.e., the two molecules must be sufficiently close to each other), the hydration of CIs is still their main atmospheric loss pathway. These results could help us get a better interpretation of the underlying CIs-aldehydes chemical processes in the global polluted urban atmospheres.


Assuntos
Atmosfera , Água , Água/química , Atmosfera/química , Aldeídos
12.
Small ; 18(49): e2204634, 2022 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-36310123

RESUMO

The precise facet modulation of transition metal nitrides (TMNs) has been regarded as an essential issue in boosting electrocatalytic H2 production. Compared to thermal nitridation, the plasma technique serves as a favorable alternative to directly achieve TMNs, but the apparent surface heating effect during plasma treatment inevitably causes the thermally stabilized nitride formation, resulting in the deterioration of the highly reactive facet. To optimize the hydrogen evolution reaction (HER) behavior, an auxiliary cooling assisted plasma system to selectively expose Ni3 N (2-10) with favorable activity by controlling surface heating during plasma nitridation is designed. The resultant nickel nitride (cp-Ni3 N) nano-framework delivers exceptional catalytic performance, evidenced by its low overpotential of 58 and 188 mV at the current density of 10 and 100 mA cm-2 for HER, in stark comparison with that of normal plasma and thermally fabricated Ni3 N. Operando plasma diagnostics along with numerical simulation further confirm the effect of surface heating on typical plasma parameters as well as the Ni3 N nanostructure, indicating the key factor responsible for the high-performance nitride electrocatalyst.

13.
Chem Rec ; 22(10): e202200083, 2022 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-35670500

RESUMO

Sodium-ion batteries (SIBs) have gained tremendous attention for large-scale energy storage applications due to the natural abundance, low cost, and even geographic distribution of sodium resources as well as a similar working mechanism to lithium-ion batteries (LIBs). One of the critical bottlenecks, however, is the design of high-performance and low-cost anode materials. Graphite anode that has dominated the market share of LIBs does not properly intercalate sodium ions. However, other carbonaceous materials are still considered as one of the most promising anode materials for SIBs in virtue of their high electronic conductivity, abundant active sites, hierarchical porosity, and excellent mechanical stability. In this review, we have tried to summarize the latest progresses made on the development of carbon-based negative electrodes (including hard carbons, soft carbons, and synthetic carbon allotropes) for SIBs. We also have provided a comprehensive understanding of their physical properties, the sodium ions storage mechanisms, and the improvement measures to cope with the current challenges. In addition, we have proposed future research directions for SIBs that will provide important insights into further development of carbon-based materials for SIBs.

14.
Phys Chem Chem Phys ; 24(30): 18205-18216, 2022 Aug 03.
Artigo em Inglês | MEDLINE | ID: mdl-35866623

RESUMO

Herein, the reaction mechanisms and kinetics for the HO2 + SO3 → HOSO2 + 3O2 reaction catalyzed by a water monomer, a water dimer and small clusters of sulfuric acid have been studied theoretically by quantum chemical methods and the Master Equation/Rice-Ramsperger-Kassel-Marcus (ME/RRKM) rate calculations. The calculated results show that when H2O is introduced into the HO2 + SO3 reaction, it not only enhances the stability of the reactant complexes by 9.0 kcal mol-1 but also reduces the energy of the transition state by 8.7 kcal mol-1. As compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 are more effective energetically, which not only results from a higher binding energy of 21.3-26.0 kcal mol-1 for the reactant complexes but also from a reduction of the energy of the transition states by 8.6-17.2 kcal mol-1. Effective rate constant calculations show that, as compared with H2O, catalysts (H2O)2, H2SO4, H2SO4⋯H2O and (H2SO4)2 can never become more efficient catalysts within the altitude range of 0-15 km due to their relatively lower concentrations. Besides, at 0 km altitude, the enhancement factor for the H2O and (k'WD1/ktot) (H2O)2-assisted HO2 + SO3 reaction within the temperature range of 280-320 K was respectively calculated to be 0.31%-0.34% and 0.16%-0.27%, while the corresponding enhancement factor of H2O and (H2O)2 at higher altitudes of 5-15 km was respectively found only 0.002%-0.12% and 0.00001%-0.022%, indicating that the contributions of H2O and (H2O)2 are not apparent in the gas-phase reaction of HO2 with SO3 especially at higher altitude. Overall, the present work will give a new insight into how a water monomer, a water dimer and small clusters of sulfuric acid catalyze the HO2 + SO3 → HOSO2 + 3O2 reaction.

15.
Phys Chem Chem Phys ; 24(8): 4966-4977, 2022 Feb 23.
Artigo em Inglês | MEDLINE | ID: mdl-35141735

RESUMO

NH2SO3H can directly participate in H2SO4-(CH3)2NH-based cluster formation, and thereby substantially enhance the cluster formation rate. Herein, the reaction mechanisms and kinetics for the formation of NH2SO3H from the hydrolysis of HNSO2 without and with neutral (H2O, (H2O)2, and (H2O)3), basic (NH3 and CH3NH2), and acidic (HCOOH, H2SO4, H2SO4⋯H2O, and (H2SO4)2) catalysts were studied theoretically at the CCSD(T)-F12/cc-pVDZ-F12//M06-2X/6-311+G(2df,2pd) level. The calculated results showed that neutral, basic, and acidic catalysts decrease the energy barrier by over 18.1 kcal mol-1; meanwhile, the product formation of NH2SO3H was more strongly bonded to neutral, basic, and acidic catalysts than to the reactants HNSO2 and H2O. This reveals that the reported neutral, basic, and acidic catalysts promote the formation of NH2SO3H from the hydrolysis of HNSO2 both kinetically and thermodynamically. Kinetic calculations using the master equation showed that (H2O)2 (100% RH) dominate over the other catalysts within the range of 0-10 km altitudes and 230-320 K with its rate ratio larger by at least 2.98 times, whereas HCOOH (3.2 × 109 molecules cm-3) is the most favorable catalysts at 15 km altitude in the troposphere. Overall, the present results will provide a definitive example that neutral, basic, and acidic catalysts have important influences on atmospheric reactions.

16.
Angew Chem Int Ed Engl ; 61(44): e202212151, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36074042

RESUMO

Flexible lithium sulfur batteries with high energy density and good mechanical flexibility are highly desirable. Here, we report a synergistic interface bonding enhancement strategy to construct flexible fiber-shaped composite cathodes, in which polypyrrole@sulfur (PPy@S) nanospheres are homogeneously implanted into the built-in cavity of self-assembled reduced graphene oxide fibers (rGOFs) by a facile microfluidic assembly method. In this architecture, sulfur nanospheres and lithium polysulfides are synergistically hosted by carbon and polymer interface, which work together to provide enhanced interface chemical bonding to endow the cathode with good adsorption ability, fast reaction kinetics, and excellent mechanical flexibility. Consequently, the PPy@S/rGOFs cathode shows enhanced electrochemical performance and high-rate capability. COMSOL Multiphysics simulations and density functional theory (DFT) calculations are conducted to elucidate the enhanced electrochemical performance. In addition, a flexible Li-S pouch cell is assembled and delivers a high areal capacity of 5.8 mAh cm-2 at 0.2 A g-1 . Our work offers a new strategy for preparation of advanced cathodes for flexible batteries.

17.
Angew Chem Int Ed Engl ; 61(14): e202116057, 2022 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-35072330

RESUMO

Work function strongly impacts the surficial charge distribution, especially for metal-support electrocatalysts when a built-in electric field (BEF) is constructed. Therefore, studying the correlation between work function and BEF is crucial for understanding the intrinsic reaction mechanism. Herein, we present a Pt@CoOx electrocatalyst with a large work function difference (ΔΦ) and strong BEF, which shows outstanding hydrogen evolution activity in a neutral medium with a 4.5-fold mass activity higher than 20 % Pt/C. Both experimental and theoretical results confirm the interfacial charge redistribution induced by the strong BEF, thus subtly optimizing hydrogen and hydroxide adsorption energy. This work not only provides fresh insights into the neutral hydrogen evolution mechanism but also proposes new design principles toward efficient electrocatalysts for hydrogen production in a neutral medium.

18.
Chemistry ; 26(18): 4128-4135, 2020 Mar 26.
Artigo em Inglês | MEDLINE | ID: mdl-31797431

RESUMO

Co-based nanoalloys show potential applications as nanocatalysts for the oxygen reduction reaction (ORR), but improving their activity is still a great challenge. In this paper, a strategy is proposed to design efficient Co-M (M=Au, Ag, Pd, Pt, Ir, and Rh) nanoalloys as ORR catalysts by using density functional theory (DFT) calculations. Through the Sabatier analysis, the overpotential as a function of ΔGOH * is identified as a quantitative descriptor for analyzing the effect of dopants and atomic structures on the activity of the Co-based nanoalloys. By adopting the suitable dopants and atomic structures, ΔGOH * accompanied by overpotential could be adjusted to the optimal range to enhance the activity of the Co-based nanoalloys. With this strategy, the core-shell structured Ag42 Co13 nanoalloy is predicted to have the highest catalytic activity for ORR among these Co-based nanoalloys. To give a deeper insight into the properties of Ag-Co nanoalloys, the structure, thermal stability, and reaction mechanism of Ag-Co nanoalloys with different compositions are also studied by using molecular simulations and DFT calculations. It is found that core-shell Ag42 Co13 exhibits the highest structural and thermal stability among these Ag-Co nanoalloys. In addition, the core-shell Ag42 Co13 shows the lowest ORR reaction energy barriers among these Ag-Co nanoalloys. It is expected that this kind of strategy could provide a viable way to design highly efficient heterogeneous catalysts in extensive applications.

19.
Nanotechnology ; 31(44): 445102, 2020 Oct 30.
Artigo em Inglês | MEDLINE | ID: mdl-32668418

RESUMO

In this work, a 'dual-key-and-lock' drug carrier was designed to respond to the tumor microenvironment (TME). A core-shell Fe-MOF@ZIF-8 was synthesized, with ZIF-8 as the shell (the first lock) to encapsulate catalase (CAT), and the Fe metal-organic framework (MOF) as the core (the second lock) to encapsulate the anticancer drug doxorubicin (DOX). Fe-MOF@ZIF-8 takes advantage of the TME-which includes a high concentration of H2O2, a weakly acidic environment and hypoxia-to achieve efficient cancer therapy. With the pH response, ZIF-8 and Fe-MOF are degraded in turn to release CAT and DOX, just like 'pH stimulation', as a key to open the two locks in turn. The released CAT reacts with the rich H2O2 in the tumor to produce O2 to regulate hypoxia, thereby improving the anticancer efficiency of the released DOX. The different cytotoxicity to L-02 cells and HeLa cells of Fe-MOF@ZIF-8 shows Fe-MOF@ZIF-8 is only harmful to cancer cells and is not harmful to normal cells. The reason is that the Fe2+/Fe3+ in Fe-MOF interact with the rich H2O2 in cancer cells to generate hydroxyl radicals (cOH), which is proved by the color of the solution of 3,3',5,5'-tetramethylbenzidine turning blue. After loading of the drug and CAT, Fe-MOF@ZIF-8 can release CAT, DOX and cOH in response to the TME, thus killing more HeLa cells. Therefore, synthesis of 'dual-key-and-lock' drug carriers responsive to the TME is a promising strategy for cancer treatment.


Assuntos
Antineoplásicos/administração & dosagem , Doxorrubicina/administração & dosagem , Portadores de Fármacos/química , Imidazóis/química , Estruturas Metalorgânicas/química , Animais , Antineoplásicos/farmacologia , Linhagem Celular Tumoral , Sobrevivência Celular/efeitos dos fármacos , Doxorrubicina/farmacologia , Liberação Controlada de Fármacos , Células HeLa , Humanos , Peróxido de Hidrogênio/química , Ferro/química , Imageamento por Ressonância Magnética , Camundongos , Neoplasias/diagnóstico por imagem , Neoplasias/tratamento farmacológico , Microambiente Tumoral/efeitos dos fármacos
20.
Molecules ; 25(17)2020 Aug 20.
Artigo em Inglês | MEDLINE | ID: mdl-32825451

RESUMO

In order to inhibit the outward-migrations of photo-initiator molecules in the ultraviolet-initiated crosslinking process and simultaneously improve the crosslinking degree and dielectric properties of crosslinked polyethylene (XLPE) materials, we have specifically developed surface-modified-SiO2/XLPE nanocomposites with the silica nanofillers that have been functionalized through chemical surface modifications. With the sulfur-containing silanes and 3-mercaptopropyl trimethoxy silane (MPTMS), the functional monomers of auxiliary crosslinker triallyl isocyanurate (TAIC) have been successfully grafted on the silica surface through thiol-ene click chemistry reactions. The grafted functional groups are verified by molecular characterizations of Fourier transform infrared spectra and nuclear magnetic resonance hydrogen spectra. Scanning electronic microscopy (SEM) indicates that the functionalized silica nanoparticles have been filled into polyethylene matrix with remarkably increased dispersivity compared with the neat silica nanoparticles. Under ultraviolet (UV) irradiation, the high efficient crosslinking reactions of polyethylene molecules are facilitated by the auxiliary crosslinkers that have been grafted onto the surfaces of silica nanofillers in polyethylene matrix. With the UV-initiated crosslinking technique, the crosslinking degree, insulation performance, and space charge characteristics of SiO2/XLPE nanocomposites are investigated in comparison with the XLPE material. Due to the combined effects of the high dispersion of nanofillers and the polar-groups of TAIC grafted on the surfaces of SiO2 nanofillers, the functionlized-SiO2/XLPE nanocomposite with an appropriate filling content represents the most preferable crosslinking degree with multiple improvements in the space charge characteristics and direct current dielectric breakdown strength. Simultaneously employing nanodielectric technology and functional-group surface modification, this study promises a modification strategy for developing XLPE nanocomposites with high mechanical and dielectric performances.


Assuntos
Nanocompostos/química , Polietileno/química , Dióxido de Silício/química , Raios Ultravioleta , Química Click
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