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1.
Angew Chem Int Ed Engl ; 61(12): e202116370, 2022 Mar 14.
Artigo em Inglês | MEDLINE | ID: mdl-35001470

RESUMO

The available processes for removing acetylene impurities from crude ethylene are tremendously energy-intensive. Herein, we demonstrate a novel aqueous Zn-C2 H2 battery, which not only switches energy-consuming acetylene removal to electricity generation, but also reduces acetylene to ethylene through a unique discharge mechanism: C2 H2 +Zn+H2 O→C2 H4 +ZnO. Under a pure acetylene stream, this Zn-C2 H2 battery exhibits an open circuit potential of 1.14 V and a peak power density of 2.2 mW cm-2 , which exceed those of reported Zn-CO2 batteries. Even for simulated crude ethylene, the Zn-C2 H2 battery manifests an acetylene conversion of 99.97 % and continuously produces polymer-grade ethylene with only ≈3 ppm acetylene during a long-term discharge operation. Such a functional battery is universally appliable for reducing other alkynes and generating electricity. Therefore, this work provides an effective strategy for green ethylene purification and the design of functional batteries.

2.
Food Funct ; 12(21): 10397-10410, 2021 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-34554172

RESUMO

Herein, we report the construction and characterization of nanoparticles based on bovine serum albumin and Hohenbuehelia serotina polysaccharides for the delivery of polyphenols isolated from the shells of Juglans regia L. (BSA-JRP-HSP NPs). We also systematically investigated their gastrointestinal digestion and colonic fermentation characteristics in vitro. BSA-JRP-HSP NPs, with amorphous properties and regular spherical morphological features, have a high encapsulation efficiency of 88.47 ± 0.04%, average particle size of 285.7 ± 3.1 nm, and zeta potential of -12.20 ± 0.61 mV, and they exhibit excellent photothermal stabilities and strong mucin adhesion capacity. Through measurements of gastrointestinal digestion and colonic fermentation in vitro, the results suggest that BSA-JRP-HSP NPs presented well-sustained release characteristics for preventing the biodegradation of JRP during gastrointestinal digestion. After gastrointestinal digestion, BSA-JRP-HSP NPs could modulate the composition and structure of gut microbiota, promoting the growth of beneficial bacterial (e.g. Prevotella, Dialister, Akkermansia, etc.) and inhibiting the growth of pathogenic bacteria (e.g. Bacteroides, Phascolarctobacterium, Lachnospiracea incertae sedis, etc.). The production of short-chain fatty acids (SCFAs) including acetic acid, propionic acid, and butyric acid was remarkably enhanced by treatment with BSA-JRP-HSP NPs. This study has proved that BSA-JRP-HSP NPs can serve as a novel candidate for improving the bioavailability of JRP.


Assuntos
Agaricales/química , Suco Gástrico/metabolismo , Microbioma Gastrointestinal , Juglans/química , Polifenóis/química , Soroalbumina Bovina/química , Agaricales/metabolismo , Disponibilidade Biológica , Colo/metabolismo , Digestão , Fezes/microbiologia , Feminino , Fermentação , Humanos , Técnicas In Vitro , Intestino Delgado/metabolismo , Juglans/metabolismo , Masculino , Nanopartículas/química , Nanopartículas/metabolismo , Polifenóis/metabolismo , Polissacarídeos/química , Polissacarídeos/metabolismo , Soroalbumina Bovina/metabolismo
3.
Int J Biol Macromol ; 191: 1-8, 2021 Nov 30.
Artigo em Inglês | MEDLINE | ID: mdl-34537291

RESUMO

In this study, Hohenbuehelia serotina polysaccharides-mucin nanoparticles (HSP-MC NPs) were fabricated based on hydrogen bonding and hydrophobicity effects for improving the bioavailability of HSP. The structural characteristics and morphology of HSP-MC NPs prepared by different conditions were respectively identified and observed. The results showed that HSP-MC NPs (HSP/MC, 1/1, w/w) presented the optimal physicochemical characteristics, with the encapsulation efficiency of 88.09 ± 0.01%, average particle size of 509.4 ± 9.76 nm and zeta potential of -20.6 ± 0.7 mV. Furthermore, HSP-MC NPs (HSP/MC, 1/1, w/w), belonged to non-crystalline substances, exhibited the excellent physicochemical stabilities against temperature, pH and ionic strength, and had the uniform spherical morphological characteristics. In addition, under simulated gastrointestinal digestion in vitro, HSP-MC NPs (HSP/MC, 1/1, w/w) showed the good sustained release performances, that might effectively improve the absorption rate of HSP. The present research is meaningful for designing the polysaccharides-loaded nano-delivery system based on natural non-toxic carrier that can be used in function food field.


Assuntos
Agaricales/química , Liberação Controlada de Fármacos , Polissacarídeos Fúngicos/química , Suco Gástrico/química , Mucinas/química , Nanopartículas/química , Polissacarídeos Fúngicos/administração & dosagem , Temperatura Alta , Ligação de Hidrogênio , Hidrólise , Interações Hidrofóbicas e Hidrofílicas , Concentração Osmolar
4.
J Colloid Interface Sci ; 592: 205-214, 2021 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-33662825

RESUMO

The leaf-shaped copper oxide (CuO) was first fabricated by a direct precipitation method. Then, the flake-shaped Co-Ni layered double hydroxides (CoNi-LDHs) were grown on the leaf-shaped CuO by using an electrodeposition method to form a unique nanostructured electrocatalyst. Due to the unique structural and compositional advantages, CoNi-LDHs wrapped around the leaf-shaped CuO exhibited good electrocatalytic characteristics. The optimized CuO/CoNi-LDHs exhibited improved non-enzymatic electrochemical sensing performance for glucose, with a reliable linear range (0.1 µM-0.384 mM) and a low limit of detection (0.065 µM, S/N = 3). The utilization of the CuO/CoNi-LDHs sensor for glucose detection in human serum was also corroborated, implying promising potential for glucose monitoring. Results demonstrated that the developed sensor provides new horizons for facile and sensitive glucose detection.


Assuntos
Técnicas Biossensoriais , Cobre , Glicemia , Automonitorização da Glicemia , Eletrodos , Glucose , Humanos , Hidróxidos , Óxidos , Folhas de Planta
5.
J Colloid Interface Sci ; 579: 12-20, 2020 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-32570026

RESUMO

Exploring a cheap catalyst with effective activity for oxygen reduction reaction (ORR) to replace precious metal electrocatalysts has gained tremendous attention for several decades. In this study, we designed and synthesized cobalt and nitrogen supported on mesoporous hollow carbon hemisphere (Co/N/HCHs) nanocomposites by a facile and economical approach. Semisphere-shaped mesoporous hollow carbon is self-generated using silica particles as template, followed by a pyrolysis-etching process; and exhibits high electrical conductivity and high specific surface. The unique porous structure of carbon provides significant number of the abundant defective sites and shortens the mass transfer pathway, leading to a greatly enhanced electrocatalytic activity with mainly 4e- reduction. Moreover, the synergistic effects of large electrochemically active areas and good electrical conductivity, resulting from the introduction of Co and N heteroatom, are the main reason for displaying outstanding ORR activity with a high half-wave potential of 0.8 V and the electron transfer numbers of 3.89. Furthermore, an excellent long-term stability (the current density retention of 87.0%) and superb methanol tolerance in alkaline medium are achieved. Undoubtedly, this demonstrates a potential way to strategically design the non-precious metal doped carbon catalysts for wider practical applications.

6.
Mater Sci Eng C Mater Biol Appl ; 110: 110747, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-32204052

RESUMO

The preparation of Pt/cerium oxide and highly ordered mesoporous carbon (Pt/CeO2/OMC) nanohybrids is reported. CeO2 can be used as an active material that enhances the electrocatalytic properties of Pt nanoparticles. OMC exhibits excellent electrical conductivity and large specific surface area, which makes it a highly promising electrocatalyst support. Benefiting from the synergistic effects of the catalytic performance of Pt/CeO2 and excellent conductivity of OMC supports, the new nanocomposite of Pt/CeO2/OMC are able to create novel features of electrocatalytic activities. Pt/CeO2/OMC tri-component composite was used as an excellent sensing platform for the determination of adrenaline. The developed sensor exhibited excellent activity and convincing analytical performance towards adrenaline, such as wide linear range, high sensitivity, low limit of detection, and low limit of quantification. In addition, the recoveries ranging from 93.4 to 103.6% were obtained in human serum samples. The successful preparation of Pt/CeO2/OMC tri-component composite may promote the development of novel electrocatalyst and facilitate the design of new electrochemical sensors.


Assuntos
Carbono/química , Cério/química , Técnicas Eletroquímicas , Epinefrina/química , Platina/química , Catálise , Oxirredução , Porosidade
7.
J Colloid Interface Sci ; 563: 189-196, 2020 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-31874306

RESUMO

The development of highly efficient, stable, and low-cost non-noble-metal electrocatalysts for oxygen evolution reactions (OER) is a major challenge for facilitate the efficiency of green energy storage. Bimetallic oxides are considered promising candidates as the electrocatalysts for OER because of their remarkable electrocatalytic activity, good stability, and low cost. In this work, ZIF-67 precursors were prepared via microwave irradiation and used as a self-sacrificing template. We proposed a rapid and scalable strategy to prepare Fe, Co bimetal embedded nanoporous carbon (Fe-Co/NPC) polyhedron composites by thermal decomposition of Fe species incorporated ZIF-67 precursor. Benefiting from the distinctive 3D polyhedron structural and compositional advantages, Fe-Co/NPC with hierarchical porous structure showed excellent electrochemical performance as ideal electrode material for OER. The resulting Fe-Co/NPC displayed outstanding electrocatalytic activity for OER with appreciable onset potential (1.59 V (vs. RHE)), small Tafel slope (53.55 mV dec-1), low over-potential (396 mV) to reach 10 mA cm-2, and excellent durability with negligible loss in current density after 1000 cycles. The current work demonstrated new insight into the design and construction of 3D structured Fe-Co/NPC polyhedron catalysts with highly electrocatalytic activity and good stability for electrocatalysis applications.

8.
Biosens Bioelectron ; 148: 111834, 2020 Jan 15.
Artigo em Inglês | MEDLINE | ID: mdl-31706175

RESUMO

Efficient platforms for detecting telomerase activity are essential for early tumor monitoring and diagnosis. Herein, an enzyme-free electroanalytical strategy was developed for reliable and highly sensitive telomerase activity assay based on the increased electrochemical signals of methylene blue (MB) catalyzed by well monodisperse Au nanorods (AuNRs). In the presence of dNTPs and telomerase extracts, the assistant DNA 1 in the double stranded DNA can be extended to telomere repeat units (TTAGGG)n, which could form a hairpin structure by telomerase-triggered extension. The assistant DNA 2 was ingeniously dissociated from the double stranded DNA to combine with capture DNA. As a result, a large amount of AuNRs could be anchored on the surface of these sequences and used for electrocatalytic oxidation of MB. The developed biosensor showed a low limit of detection of 8.20 HeLa cells mL-1 and a wide dynamic range from 30 to 1.04 × 107 HeLa cells mL-1 for the determination of telomerase activity, which can provide a new way for telomerase activity assays in early diagnosis for cancers.


Assuntos
Técnicas Biossensoriais/métodos , Ouro/química , Nanotubos/química , Telomerase/análise , DNA/química , Técnicas Eletroquímicas/métodos , Ensaios Enzimáticos/métodos , Células HeLa , Humanos , Nanotubos/ultraestrutura
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