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1.
ACS Nano ; 2024 May 16.
Artigo em Inglês | MEDLINE | ID: mdl-38752679

RESUMO

Thanks to their excellent photoelectric characteristics to generate cytotoxic reactive oxygen species (ROS) under the light-activation process, TiO2 nanomaterials have shown significant potential in photodynamic therapy (PDT) for solid tumors. Nevertheless, the limited penetration depth of TiO2-based photosensitizers and excitation sources (UV/visible light) for PDT remains a formidable challenge when confronted with complex tumor microenvironments (TMEs). Here, we present a H2O2-driven black TiO2 mesoporous nanomotor with near-infrared (NIR) light absorption capability and autonomous navigation ability, which effectively enhances solid tumor penetration in NIR light-triggered PDT. The nanomotor was rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of a NIR light-responsive black TiO2 nanosphere and an enzyme-modified periodic mesoporous organosilica (PMO) nanorod that wraps around the TiO2 nanosphere. The overexpressed H2O2 can drive the nanomotor in the TME under catalysis of catalase in the PMO domain. By precisely controlling the ratio of TiO2 and PMO compartments in the Janus nanostructure, TiO2&PMO nanomotors can achieve optimal self-propulsive directionality and velocity, enhancing cellular uptake and facilitating deep tumor penetration. Additionally, by the decomposition of endogenous H2O2 within solid tumors, these nanomotors can continuously supply oxygen to enable highly efficient ROS production under the NIR photocatalysis of black TiO2, leading to intensified PDT effects and effective tumor inhibition.

2.
Angew Chem Int Ed Engl ; : e202403245, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38578838

RESUMO

The encapsulation of functional colloidal nanoparticles (100 nm) into single-crystalline ZSM-5 zeolites, aiming to create uniform core-shell structures, is a highly sought-after yet formidable objective due to significant lattice mismatch and distinct crystallization properties. In this study, we demonstrate the fabrication of a core-shell structured single-crystal zeolite encompassing an Fe3O4 colloidal core via a novel confinement stepwise crystallization methodology. By engineering a confined nanocavity, anchoring nucleation sites, and executing stepwise crystallization, we have successfully encapsulated colloidal nanoparticles (CN) within single-crystal zeolites. These grafted sites, alongside the controlled crystallization process, compel the zeolite seed to nucleate and expand along the Fe3O4 colloidal nanoparticle surface, within a meticulously defined volume (1.5×107≤V≤1.3×108 nm3). Our strategy exhibits versatility and adaptability to an array of zeolites, including but not restricted to ZSM-5, NaA, ZSM-11, and TS-1 with polycrystalline zeolite shell. We highlight the uniformly structured magnetic-nucleus single-crystalline zeolite, which displays pronounced superparamagnetism (14 emu/g) and robust acidity (~0.83 mmol/g). This innovative material has been effectively utilized in a magnetically stabilized bed (MSB) reactor for the dehydration of ethanol, delivering an exceptional conversion rate (98 %), supreme ethylene selectivity (98 %), and superior catalytic endurance (in excess of 100 hours).

3.
J Am Chem Soc ; 146(9): 6199-6208, 2024 Mar 06.
Artigo em Inglês | MEDLINE | ID: mdl-38394360

RESUMO

A reliable solid electrolyte interphase (SEI) on the metallic Zn anode is imperative for stable Zn-based aqueous batteries. However, the incompatible Zn-ion reduction processes, scilicet simultaneous adsorption (capture) and desolvation (repulsion) of Zn2+(H2O)6, raise kinetics and stability challenges for the design of SEI. Here, we demonstrate a tandem chemistry strategy to decouple and accelerate the concurrent adsorption and desolvation processes of the Zn2+ cluster at the inner Helmholtz layer. An electrochemically assembled perforative mesopore SiO2 interphase with tandem hydrophilic -OH and hydrophobic -F groups serves as a Janus mesopores accelerator to boost a fast and stable Zn2+ reduction reaction. Combining in situ electrochemical digital holography, molecular dynamics simulations, and spectroscopic characterizations reveals that -OH groups capture Zn2+ clusters from the bulk electrolyte and then -F groups repulse coordinated H2O molecules in the solvation shell to achieve the tandem ion reduction process. The resultant symmetric batteries exhibit reversible cycles over 8000 and 2000 h under high current densities of 4 and 10 mA cm-2, respectively. The feasibility of the tandem chemistry is further evidenced in both Zn//VO2 and Zn//I2 batteries, and it might be universal to other aqueous metal-ion batteries.

4.
Small ; 20(15): e2307378, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38009801

RESUMO

The high-current-density Zn-air battery shows big prospects in next-generation energy technologies, while sluggish O2 reaction and diffusion kinetics barricade the applications. Herein, the sequential assembly is innovatively demonstrated for hierarchically mesoporous molybdenum carbides/carbon microspheres with a tunable thickness of mesoporous carbon layers (Meso-Mo2C/C-x, where x represents the thickness). The optimum Meso-Mo2C/C-14 composites (≈2 µm in diameter) are composed of mesoporous nanosheets (≈38 nm in thickness), which possess bilateral mesoporous carbon layers (≈14 nm in thickness), inner Mo2C/C layers (≈8 nm in thickness) with orthorhombic Mo2C nanoparticles (≈2 nm in diameter), a high surface area of ≈426 m2 g-1, and open mesopores (≈6.9 nm in size). Experiments and calculations corroborate the hierarchically mesoporous Mo2C/C can enhance hydrophilicity for supplying sufficient O2, accelerate oxygen reduction kinetics by highly-active Mo2C and N-doped carbon sites, and facilitate O2 diffusion kinetics over hierarchically mesopores. Therefore, Meso-Mo2C/C-14 outputs a high half-wave potential (0.88 V vs RHE) with a low Tafel slope (51 mV dec-1) for oxygen reduction. More significantly, the Zn-air battery delivers an ultrahigh power density (272 mW cm-2), and an unprecedented 100 h stability at a high-current-density condition (100 mA cm-2), which is one of the best performances.

5.
ACS Omega ; 8(43): 40063-40077, 2023 Oct 31.
Artigo em Inglês | MEDLINE | ID: mdl-37929122

RESUMO

Ternary NiO/Ag/TiO2 heterojunction photocatalyst was prepared by deposition coprecipitation for visible light photocatalytic applications. Physicochemical properties of the synthesized NiO/Ag/TiO2 composite were characterized by X-ray diffraction, Brunauer-Emmett-Teller surface area measurement method, transmission electron microscopy, energy-dispersive X-ray spectroscopy techniques, X-ray photoelectron spectroscopy technique, and ultraviolet-visible absorption spectroscopy. The results suggest that the well-dispersed small metallic silver nanoparticles (<3 nm) facilitate electron transfer and bridge nickel oxide and titanium oxide. The photocatalytic degradation and the methylene blue (MB) dye kinetics were carried out on a ternary NiO/Ag/TiO2 composite and compared to bare TiO2 under visible light irradiation. The results indicate that NiO/Ag/TiO2 has superior MB photodegradation efficiency with a high reaction rate constant and low degradation time (93.15% within 60 min) compared to Ag/TiO2, NiO/TiO2, and bare TiO2. NiO/Ag/TiO2 nanocomposite was also investigated for the most common pharmaceutical waste degradation and exhibited excellent degradation efficiency. The enhancement of the composite's performance could be attributed to the surface plasmonic resonance of the Ag nanoparticles, the formation of Schottky junctions at the Ag-TiO2 and Ag-NiO interface, and the p-n heterojunction between NiO and TiO2. Ag NPs act as a photosynthesizer and a photocatalyst, facilitate electron transfer, shift the absorption to the visible light region, reduce the band gap of TiO2, suppress the electron-hole recombination, and enhance the photocatalytic activity and stability as a result.

6.
J Am Chem Soc ; 145(44): 24284-24293, 2023 Nov 08.
Artigo em Inglês | MEDLINE | ID: mdl-37888942

RESUMO

Zinc metal-based aqueous batteries (ZABs) offer a sustainable, affordable, and safe energy storage alternative to lithium, yet inevitable dendrite formation impedes their wide use, especially under long-term and high-rate cycles. How the battery can survive after dendrite formation remains an open question. Here, we pivot from conventional Zn dendrite growth suppression strategies, introducing proactive dendrite-digesting chemistry via a mesoporous Ti3C2 MXene (MesoTi3C2)-wrapped polypropylene separator. Spectroscopic characterizations and electrochemical evaluation demonstrate that MesoTi3C2, acting as an oxidant, can revive the formed dead Zn0 dendrites into electroactive Zn2+ ions through a spontaneous redox process. Density functional theory reveals that the abundant edge-Ti-O sites in our MesoTi3C2 facilitate high oxidizability and electron transfer from Zn0 dendrites compared to their in-plane counterparts. The resultant asymmetrical cell demonstrates remarkable ultralong cycle life of 2200 h at a practical current of 5 mA cm-2 with a low overpotential (<50 mV). The study reveals the unexpected edge effect of mesoporous MXenes and uncovers a new proactive dendrite-digesting chemistry to survive ZABs, albeit with inevitable dendrite formation.

7.
Nat Chem ; 15(6): 832-840, 2023 06.
Artigo em Inglês | MEDLINE | ID: mdl-37055572

RESUMO

The ability of Janus nanoparticles to establish biological logic systems has been widely exploited, yet conventional non/uni-porous Janus nanoparticles are unable to fully mimic biological communications. Here we demonstrate an emulsion-oriented assembly approach for the fabrication of highly uniform Janus double-spherical MSN&mPDA (MSN, mesoporous silica nanoparticle; mPDA, mesoporous polydopamine) nanoparticles. The delicate Janus nanoparticle possesses a spherical MSN with a diameter of ~150 nm and an mPDA hemisphere with a diameter of ~120 nm. In addition, the mesopore size in the MSN compartment is tunable from ~3 to ~25 nm, while those in the mPDA compartments range from ~5 to ~50 nm. Due to the different chemical properties and mesopore sizes in the two compartments, we achieve selective loading of guests in different compartments, and successfully establish single-particle-level biological logic gates. The dual-mesoporous structure enables consecutive valve-opening and matter-releasing reactions within one single nanoparticle, facilitating the design of single-particle-level logic systems.


Assuntos
Nanopartículas , Emulsões , Nanopartículas/química , Compostos de Diazônio , Piridinas , Dióxido de Silício/química , Porosidade
8.
Angew Chem Int Ed Engl ; 62(14): e202216188, 2023 03 27.
Artigo em Inglês | MEDLINE | ID: mdl-36722433

RESUMO

Due to non-specific strong nano-bio interactions, it is difficult for nanocarriers with permanent rough surface to cross multiple biological barriers to realize efficient drug delivery. Herein, a camouflaged virus-like-nanocarrier with a transformable rough surface is reported, which is composed by an interior virus-like mesoporous SiO2 nanoparticle with a rough surface (vSiO2 ) and an exterior acid-responsive polymer. Under normal physiological pH condition, the spikes on vSiO2 are hidden by the polymer shell, and the non-specific strong nano-bio interactions are effectively inhibited. While in the acidic tumor microenvironment, the nanocarrier sheds the polymer camouflage to re-expose its rough surface. So, the retention ability and endocytosis efficiency of the nanocarrier are great improved. Owing to it's the dynamically variable rough surface, the rationally designed nanocarrier exhibits extended blood-circulation-time and enhanced tumor accumulation.


Assuntos
Portadores de Fármacos , Nanopartículas , Dióxido de Silício , Sistemas de Liberação de Medicamentos , Polímeros , Doxorrubicina/farmacologia , Linhagem Celular Tumoral
9.
Sci Adv ; 8(30): eabq2356, 2022 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-35905185

RESUMO

Rare earth-based nanomaterials that have abundant optical, magnetic, and catalytic characteristics have many applications. The controllable introduction of mesoporous channels can further enhance its performance, such as exposing more active sites of rare earth and improving the loading capacity, yet remains a challenge. Here, we report a universal viscosity-mediated assembly strategy and successfully endowed rare earth-based nanoparticles with central divergent dendritic mesopores. More than 40 kinds of dendritic mesoporous rare earth-based (DM-REX) nanoparticles with desired composition (single or multiple rare earth elements, high-entropy compounds, etc.), particle diameter (80 to 500 nanometers), pore size (3 to 20 nanometers), phase (amorphous hydroxides, crystalline oxides, and fluorides), and architecture were synthesized. Theoretically, a DM-REX nanoparticle library with 393,213 kinds of possible combinations can be constructed on the basis of this versatile method, which provides a very broad platform for the application of rare earth-based nanomaterials with rational designed functions and structures.

10.
Nano Lett ; 22(10): 4223-4231, 2022 May 25.
Artigo em Inglês | MEDLINE | ID: mdl-35507684

RESUMO

Zn-based aqueous batteries (ZABs) have been regarded as promising candidates for safe and large-scale energy storage in the "post-Li" era. However, kinetics and stability problems of Zn capture cannot be concomitantly regulated, especially at high rates and loadings. Herein, a hierarchical confinement strategy is proposed to design zincophilic and spatial traps through a host of porous Co-embedded carbon cages (denoted as CoCC). The zincophilic Co sites act as preferred nucleation sites with low nucleation barriers (within 0.5 mA h cm-2), and the carbon cage can further spatially confine Zn deposition (within 5.0 mA h cm-2). Theoretical simulations and in situ/ex situ structural observations reveal the hierarchical spatial confinement by the elaborated all-in-one network (within 12 mA h cm-2). Consequently, the elaborate strategy enables a dendrite-free behavior with excellent kinetics (low overpotential of ca. 65 mV at a high rate of 20 mA cm-2) and stable cycle life (over 800 cycles), pushing forward the next-generation high-performance ZABs.

11.
Membranes (Basel) ; 12(4)2022 Apr 06.
Artigo em Inglês | MEDLINE | ID: mdl-35448377

RESUMO

Obstacles in the membrane-based separation field are mainly related to membrane fouling. This study involved the synthesis and utilization of covalently crosslinked MXene/cellulose acetate mixed matrix membranes with MXene at different concentrations (CCAM-0% to CCAM-12%) for water purification applications. The membranes' water flux, dye, and protein rejection performances were compared using dead-end (DE) and crossflow (CF) filtration. The fabricated membranes, especially CCAM-10%, exhibited high hydrophilicity, good surface roughness, significantly high water flux, high water uptake, and high porosity. A significantly higher flux was observed in CF filtration relative to DE filtration. Moreover, in CF filtration, the CCAM-10% membrane exhibited 96.60% and 99.49% rejection of methyl green (MG) and bovine serum albumin (BSA), respectively, while maintaining a flux recovery ratio of 67.30% and an irreversible fouling ratio at (Rir) of 32.70, indicating good antifouling performance. Hence, this study suggests that covalent modification of cellulose acetate membranes with MXene significantly improves the performance and fouling resistance of membranes for water filtration in CF mode relative to DE mode.

12.
J Am Chem Soc ; 144(9): 3892-3901, 2022 03 09.
Artigo em Inglês | MEDLINE | ID: mdl-35191672

RESUMO

As one of the most important parameters of the nanomotors' motion, precise speed control of enzyme-based nanomotors is highly desirable in many bioapplications. However, owing to the stable physiological environment, it is still very difficult to in situ manipulate the motion of the enzyme-based nanomotors. Herein, inspired by the brakes on vehicles, the near-infrared (NIR) "optical brakes" are introduced in the glucose-driven enzyme-based mesoporous nanomotors to realize remote speed regulation for the first time. The novel nanomotors are rationally designed and fabricated based on the Janus mesoporous nanostructure, which consists of the SiO2@Au core@shell nanospheres and the enzymes-modified periodic mesoporous organosilicas (PMOs). The nanomotor can be driven by the biofuel of glucose under the catalysis of enzymes (glucose oxidase/catalase) on the PMO domain. Meanwhile, the Au nanoshell at the SiO2@Au domain enables the generation of the local thermal gradient under the NIR light irradiation, driving the nanomotor by thermophoresis. Taking advantage of the unique Janus nanostructure, the directions of the driving force induced by enzyme catalysis and the thermophoretic force induced by NIR photothermal effect are opposite. Therefore, with the NIR optical speed regulators, the glucose-driven nanomotors can achieve remote speed manipulation from 3.46 to 6.49 µm/s (9.9-18.5 body-length/s) at the fixed glucose concentration, even after covering with a biological tissue. As a proof of concept, the cellar uptake of the such mesoporous nanomotors can be remotely regulated (57.5-109 µg/mg), which offers great potential for designing smart active drug delivery systems based on the mesoporous frameworks of this novel nanomotor.


Assuntos
Nanoestruturas , Dióxido de Silício , Sistemas de Liberação de Medicamentos , Glucose , Glucose Oxidase , Nanoestruturas/química , Dióxido de Silício/química
13.
Nano Lett ; 21(14): 6071-6079, 2021 07 28.
Artigo em Inglês | MEDLINE | ID: mdl-34269590

RESUMO

Streamlined architectures with a low fluid-resistance coefficient have been receiving great attention in various fields. However, it is still a great challenge to synthesize streamlined architecture with tunable surface curvature at the nanoscale. Herein, we report a facile interfacial dynamic migration strategy for the synthesis of streamlined mesoporous nanotadpoles with varied architectures. These tadpole-like nanoparticles possess a big streamlined head and a slender tail, which exhibit large inner cavities (75-170 nm), high surface areas (424-488 m2 g-1), and uniform mesopore sizes (2.4-3.2 nm). The head curvature of the streamlined mesoporous nanoparticles can be well-tuned from ∼2.96 × 10-2 to ∼5.56 × 10-2 nm-1, and the tail length can also be regulated from ∼30 to ∼650 nm. By selectively loading the Fe3O4 catalyst in the cavity of the streamlined silica nanotadpoles, the H2O2-driven mesoporous nanomotors were designed. The mesoporous nanomotors with optimized structural parameters exhibit outstanding directionality and a diffusion coefficient of 8.15 µm2 s-1.


Assuntos
Nanopartículas , Dióxido de Silício , Catálise , Peróxido de Hidrogênio , Porosidade
14.
Mater Sci Eng C Mater Biol Appl ; 122: 111910, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33641906

RESUMO

Carbon nanofibers (CNFs) have been implicated in biomedical applications, yet, they are still considered as a potential hazard. Conversely, mesoporous silica is a biocompatible compound that has been used in various biomedical applications. In this regard, we recently reported that CNFs induce significant toxicity on the early stage of embryogenesis in addition to the inhibition of its angiogenesis. Thus, we herein use mesoporous silica coating of CNFs (MCNFs) in order to explore their outcome on normal development and angiogenesis using avian embryos at 3 days and its chorioallantoic membrane (CAM) at 6 days of incubation. Our data show that mesoporous silica coating of CNFs significantly reduces embryotoxicity provoked by CNFs. However, MCNFs exhibit slight increase in angiogenesis inhibition in comparison with CNFs. Further investigation revealed that MCNFs slightly deregulate the expression patterns of key controller genes involved in cell proliferation, survival, angiogenesis, and apoptosis as compared to CNFs. We confirmed these data using avian primary normal embryonic fibroblast cells established in our lab. Regarding the molecular pathways, we found that MCNFs downregulate the expression of ERK1/ERK2, p-ERK1/ERK2 and JNK1/JNK2/JNK3, thus indicating a protective role of MCNFs via ERK and JNK pathways. Our data suggest that coating CNFs with a layer of mesoporous silica can overcome their toxicity making them suitable for use in biomedical applications. Nevertheless, further investigations are required to evaluate the effects of MCNFs and their mechanisms using different in vitro and in vivo models.


Assuntos
Nanofibras , Animais , Carbono , Membrana Corioalantoide , Sistema de Sinalização das MAP Quinases , Nanofibras/toxicidade , Dióxido de Silício/toxicidade
15.
J Biomed Mater Res B Appl Biomater ; 109(11): 1893-1908, 2021 11.
Artigo em Inglês | MEDLINE | ID: mdl-33749098

RESUMO

Since the discovery and fabrication of carbon nanofibers (CNFs) over a decade ago, scientists foster to discover novel myriad potential applications for this material in both biomedicine and industry. The unique economic viability, mechanical, electrical, optical, thermal, and structural properties of CNFs led to their rapid emergence. CNFs become an artificial intelligence platform for different uses, including a wide range of biomedical applications. Furthermore, CNFs have exceptionally large surface areas that make them flexible for tailoring and functionalization on demand. This review highlights the recent progress and achievements of CNFs in a wide range of biomedical fields, including cancer therapy, biosensing, tissue engineering, and wound dressing. Besides the synthetic techniques of CNFs, their potential toxicity and limitations, as biomaterials in real clinical settings, will be presented. This review discusses CNF's future investigations in other biomedical fields, including gene delivery and bioimaging and CNFs risk assessment.


Assuntos
Bandagens , Materiais Biocompatíveis/química , Técnicas Biossensoriais , Carbono/química , Técnicas de Transferência de Genes , Nanofibras/química , Engenharia Tecidual , Humanos
16.
J Biomed Nanotechnol ; 16(6): 975-984, 2020 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33187592

RESUMO

Implementation of carbon nanofibers (CNFs) in biomedical applications have successful outcomes, however, they are still considered as a potential hazard. We herein used avian embryos at 3 days and its chorioallantoic membrane (CAM) at 6 days of incubation to evaluate the impact of synthesized CNFs on the early stage of embryogenesis and angiogenesis. Our data point out that 50 µg/embryo concentration of CNFs provoke adverse effects as 75% of CNFs-exposed embryos die within 1-5 days after exposure compared with their matched controls. Furthermore, CNFs significantly inhibit angiogenesis of the CAM after 48-hours post-treatment. Additionally, RT-PCR analysis on seven key controller genes responsible for proliferation, survival, angiogenesis, and apoptosis showed that these genes are deregulated in brain, heart, and liver tissues of CNFs-exposed embryos compared to their matched control. Our investigation suggests that CNFs could have a toxic effect on the early stages of embryogenesis as well as angiogenesis. Nevertheless, further investigations are required to evaluate the effects of CNFs and elucidate their mechanism on the early stage of the normal development and human health.


Assuntos
Nanofibras , Animais , Apoptose , Carbono , Membrana Corioalantoide , Humanos , Nanofibras/toxicidade , Neovascularização Patológica
17.
Nanomaterials (Basel) ; 10(10)2020 Sep 25.
Artigo em Inglês | MEDLINE | ID: mdl-32992907

RESUMO

MXenes have emerged as promising materials for various mechanical applications due to their outstanding physicochemical merits, multilayered structures, excellent strength, flexibility, and electrical conductivity. Despite the substantial progress achieved in the rational design of MXenes nanostructures, the tutorial reviews on the mechanical properties of self-standing MXenes were not yet reported to our knowledge. Thus, it is essential to provide timely updates of the mechanical properties of MXenes, due to the explosion of publications in this filed. In pursuit of this aim, this review is dedicated to highlighting the recent advances in the rational design of self-standing MXene with unique mechanical properties for various applications. This includes elastic properties, ideal strengths, bending rigidity, adhesion, and sliding resistance theoretically as well as experimentally supported with various representative paradigms. Meanwhile, the mechanical properties of self-standing MXenes were compared with hybrid MXenes and various 2D materials. Then, the utilization of MXenes as supercapacitors for energy storage is also discussed. This review can provide a roadmap for the scientists to tailor the mechanical properties of MXene-based materials for the new generations of energy and sensor devices.

18.
Cancers (Basel) ; 12(7)2020 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-32708521

RESUMO

Recently, nanomedicines have gained a great deal of attention in diverse biomedical applications, including anti-cancer therapy. Being different from normal tissue, the biophysical microenvironment of tumor cells and cancer cell mechanics should be considered for the development of nanostructures as anti-cancer agents. Throughout the last decades, many efforts devoted to investigating the distinct cancer environment and understanding the interactions between tumor cells and have been applied bio-nanomaterials. This review highlights the microenvironment of cancer cells and how it is different from that of healthy tissue. We gave special emphasis to the physiological shear stresses existing in the cancerous surroundings, since these stresses have a profound effect on cancer cell/nanoparticle interaction. Finally, this study reviews relevant examples of investigations aimed at clarifying the cellular nanoparticle uptake behavior under both static and dynamic conditions.

19.
ACS Appl Mater Interfaces ; 12(28): 31309-31318, 2020 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-32538605

RESUMO

Multidimensional bimetallic Pt-based nanoarchitectonics are highly promising in electrochemical energy conversion technologies because of their fancy structural merits and accessible active sites; however, hitherto their precise template-free fabrication remains a great challenge. We report a template-free solvothermal one-pot approach for the rational design of cocentric PtNi multicube nanoarchitectonics via adjusting the oleylamine/oleic acid ratio with curcumin. The obtained multidimensional PtNi multicubes comprise multiple small interlace-stacked nanocube subunits assembled in spatially porous branched nanoarchitectonics and bound by high-index facets. The synthetic mechanism is driven by spontaneous isolation among prompt nucleation and oriented attachment epitaxial growth. These inimitable architectural and compositional merits of PtNi multicubes endowed the ethanol oxidation mass and specific activity by 5.6 and 9.03 times than the Pt/C catalyst, respectively, along with the enhancement of methanol oxidation mass activity by 2.3 times. Moreover, PtNi multicubes showed superior durability and a higher tolerance for CO poisoning than the Pt/C catalyst. This work may pave the way for tailored preparation of Pt-based nanoarchitectonics for myriad catalytic reactions.

20.
J Biomed Nanotechnol ; 16(3): 364-372, 2020 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-32493546

RESUMO

MXene (Ti3C2Tx), as a novel 2D material, has produced a great interest due to its promising properties in biomedical applications, nevertheless, there is a lack of studies dedicated to investigate the possible toxic effect of MXene in embryos. Herein, we aim to scrutinize the potential toxicity of MXene nanosheets on the early stage of the embryo as well as angiogenesis. Avian embryos at 3 and 5 days of incubation were used as an experimental model in this investigation. Our findings reveal that MXene may produce adverse effect on the early stage of embryogenesis as ∼46% of MXene-exposed embryos died during 1-5 days after exposure. We also found that MXene at tested concentration inhibits angiogenesis of the chorioallantoic membrane of the embryo after 5 days of incubation. More significantly, RT-PCR analysis of seven genes, which are key regulators of cell proliferation, survival, cell death and angiogenesis, revealed that these genes were deregulated in brain, heart and liver tissues from MXene-treated embryos in comparison with their matched controls. Our study clearly suggests that MXene at studied concentration might induce a toxic effect on the early stage of embryogenesis; nevertheless, more investigations are necessary to understand the effect at low concentrations and elucidate its mechanism at the early stage of normal development.


Assuntos
Nanoestruturas , Neovascularização Patológica , Morte Celular , Proliferação de Células , Membrana Corioalantoide
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