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1.
Biosens Bioelectron ; 259: 116387, 2024 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-38754194

RESUMEN

The incidence of esophageal cancer is positively associated with fumonisin contamination. It is necessary to develop methods for the rapid detection of fumonisins. In this work, a self-powered photoelectrochemical aptamer sensor based on ZnIn2S4/WO3 photoanode and Au@W-Co3O4 photocathode is proposed for the sensitive detection of fumonisin B1 (FB1). Among them, under visible light irradiation, the Z-type heterostructure of ZnIn2S4/WO3 acts as a photoanode to improve the electron transfer rate, which contributes to the enhancement of the photocathode signal and lays the foundation for a wider detection range. The Au@W-Co3O4 photocathode as a sensing interface reduces the probability of false positives (comparison of anode sensing platforms). The PEC sensor has a good working performance in the detection range (10 pg/mL-1000 ng/mL) with a detection limit of 2.7 pg/mL (S/N = 3). In addition, the sensor offers good selectivity, stability and excellent recoveries in real sample analysis. This work is expected to play a role in the field of analyzing environmental toxins.


Asunto(s)
Aptámeros de Nucleótidos , Técnicas Biosensibles , Técnicas Electroquímicas , Fumonisinas , Límite de Detección , Fumonisinas/análisis , Fumonisinas/química , Aptámeros de Nucleótidos/química , Tungsteno/química , Electrodos , Óxidos/química , Oro/química , Humanos , Luz , Zinc/química
2.
Anal Chim Acta ; 1310: 342703, 2024 Jun 29.
Artículo en Inglés | MEDLINE | ID: mdl-38811134

RESUMEN

BACKGROUND: Photoelectrochemical (PEC) sensors have attracted much attention due to their low cost, simple instrumentation and high sensitivity. However, conventional PEC sensors require layer-by-layer modification of the photoelectrode surface, which has the disadvantages of being time-consuming and unstable. In addition, complex interfering substances in real samples may lead to false-positive or false-negative detection results. It was thought that the above drawbacks could be eliminated by the construction of a polarity inversion PEC sensor. In this work, a magnetically separated PEC sensor was constructed for the detection of Carcinoembryonic antigen (CEA). RESULTS: During the experiment, the construction of the sensor was used for sensitive detection of CEA. In the experimental process, Fe3O4@SiO2@CdS, a semiconductor material with magnetic properties, was chosen as the substrate material, and ZnO/CuO was used as the marker on the DNA2 molecule, and a split magnetic separation PEC sensor was constructed, which was used to realize the sensitive detection of CEA. Eventually, the detection range of the sensor for CEA detection is 1-10000 pg/mL, with the detection limit of 0.34 pg/mL. Additionally, the PEC sensor has the advantages of high speed, high efficiency, high sensitivity, good specificity, and high stability. The sensing platform constructed in this work can also be extended to detect other targets, which provides a new idea for PEC sensing platforms. SIGNIFICANCE: In this experiment, we developed a split PEC immunosensor based on magneto-optic nanostructure and photocurrent polarity switching strategy. Specifically, the proposed magnetic nanostructure Fe3O4@SiO2@CdS-DNA1 exhibits good paramagnetism and dispersion ability. By magnetic separation process, the PEC signals of opposite polarity can be obtained.

3.
Talanta ; 275: 126125, 2024 Aug 01.
Artículo en Inglés | MEDLINE | ID: mdl-38663066

RESUMEN

The establishment of rapid target analysis methods for cytokeratin fragment antigen 21-1 (CYFRA 21-1) is urgently needed. [Ir(pbi)2(acac)] (pbi = 2-(4-bromophenyl)-1-hydrogen -benzimidazole, acac = acetylacetonate) as traditional electrochemiluminescence (ECL) luminophores has been confined due to its non-negligible dark toxicity and poor water solubility leading to poor biocompatibility and electrical conductivity as an organic molecule. Hence, to overcome this limitation, [Ir(pbi)2(acac)] can be effectively loaded on the polyvinyl alcohol hydrogel modified Ti3C2Tx MXene surface (Ir@Ti3C2Tx-PVA) as sensing platform which can emit high ECL signals. Then, a quenching strategy was proposed to fabricate an ECL sandwich immunosensor using H2O2 as quencher molecules which can generated by Pd@Au0.85Pd0.15. Especially, the generation of O2 to H2O2 can be achieved through a two-electron (2e-) reaction pathway by Pd@Au0.85Pd0.15, to overcome the restriction that the H2O2 was virtually impossible to label or immobilize on the non-enzyme nanomaterials. The proposed ECL assay achieves a response to CYFRA 21-1 within the range of 0.1 pg/mL-100 ng/mL, with a detection limit of 8.9 fg/mL (S/N = 3). This work provided a feasible tactic to seek superior-performance ECL luminophore and quencher consequently set up a novel means to makeup ultrasensitive ECL biosensor, which extended the utilization potential of Ir(pbi)2(acac) in ECL assays.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Oro , Peróxido de Hidrógeno , Queratina-19 , Mediciones Luminiscentes , Paladio , Alcohol Polivinílico , Peróxido de Hidrógeno/química , Peróxido de Hidrógeno/análisis , Técnicas Electroquímicas/métodos , Paladio/química , Catálisis , Técnicas Biosensibles/métodos , Alcohol Polivinílico/química , Oro/química , Humanos , Mediciones Luminiscentes/métodos , Queratina-19/análisis , Inmunoensayo/métodos , Antígenos de Neoplasias/análisis , Antígenos de Neoplasias/inmunología , Titanio/química , Límite de Detección , Iridio/química , Nanopartículas del Metal/química
4.
Nanoscale ; 16(18): 8851-8857, 2024 May 09.
Artículo en Inglés | MEDLINE | ID: mdl-38644784

RESUMEN

The electrochemical nitrate reduction reaction (NO3-RR) is a novel green method for ammonia synthesis. However, the lack of sufficient catalysts has hindered the development of the NO3-RR. This research develops a transformation of porous CoP@N-C/CC into porous phosphorus-rich CoP4@N-C/CC through high-temperature calcination. Due to its unique phosphating-rich structure, CoP4@N-C/CC exhibits an excellent Faraday efficiency (FE: 92.3%) and NH3 yield (610.2 µmol h-1 cm-2). Such a catalyst with more P-P bonds can provide more active sites, effectively enhancing the adsorption and reaction processes of reactant molecules. In addition, the catalyst has good durability and catalytic stability, which provides a possibility for the future application of electrocatalytic ammonia production.

5.
Talanta ; 273: 125959, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38537493

RESUMEN

The improvement of electrochemiluminescence (ECL) performance relies on the electron transfer efficiency between luminophore and coreactant. An ultrasensitive ECL micro-reactor with confinement-enhanced performance was prepared by using the covalent organic framework-LZU1-functionalized metal-organic framework (MOF@COF-LZU1) as a platform to assemble enormous N,N-dibutyl-2-hydroxyethylamine (DBAE) and tris(4,4'-dicarboxylic acid-2,2'-bipyridyl) ruthenium(II) [Ru(dcbpy)32+] into its pore channels. Compared to individual substances of γ-CD-MOF and COF-LZU1, the synergistic effects can conduce to the enhancement of the intensity, durability and sensitivity of the micro-reactor. Besides, COF-LZU1 can provide a mild environment to accommodate a certain amount of DBAE by concentrating them from the aqueous solution into its hydrophobic cavities and boost the oxidation efficiency of DBAE to generate more DBAE●+ and profited the survival of DBAE●, leading to an improved reaction efficiency with the Ru(dcbpy)32+ intermediate. Thanks to the confinement-enhanced strategy, engineered as high-functioning luminescent materials, Ru@γ-CD-MOF@COF-LZU1 micro-reactors decorated with Au NPs can facilitate electron transfer and capture primary antibodies (Ab1). Moreover, Au-Pd-Pt noble metal aerogels (NMAs) functionalized MoS2 NFs (Au-Pd-Pt NMAs@MoS2 NFs) were chosen as base material due to its large specific surface areas, high porosity, and excellent electrical conductivity. Based on above merits, the sensor demonstrated a sensitive response to CYFRA 21-1 detection in a linear concentration gradient from 10 fg/mL to 50 ng/mL with a detection limit of 0.0055 pg/mL (S/N = 3). The COF-LZU1 decorated ECL micro-reactors were constructed based on the signal amplification strategies to realize accurate CYFRA 21-1 detection.

6.
Talanta ; 273: 125871, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38458083

RESUMEN

Lead ions (Pb2+) are heavy metal ions that are harmful to living organisms and ecosystems. It is important to realize sensitive detection of Pb2+ in the environment. In this study, a signal enhancement photoelectrochemical (PEC) sensor with high sensitivity was constructed for the detection of Pb2+. Firstly, to obtain excellent electron transfer performance, sulfur defect-engineered Bi2S3-x/In2S3-y mediated signal enhancement formed by Bi2S3 and In2S3 with well-matched structure in terms of energy level as the substrate materials. In this case, the introduction of sulfur vacancies further affects the electronic structure of the material, which significantly improves the electrical conductivity and effectively increases the electron transfer rate. In addition, the as-synthesized Cu@Cu2O nanosphere is chosen as the marker to accelerate the electron transfer through the surface plasmon resonance effect of Cu. The constructed sensor was able to detect Pb2+ in the range of 1 ng mL-1-100 µg mL-1 with a limit of detection of 19.2 pg mL-1. The sensor exhibits good reproducibility, specificity, and stability, indicating such PEC sensor can achieve the sensitive detection of Pb2+ in the environment. This work paves a new way for the construction of PEC sensors and the specific PEC detection of Pb2+ in environmental waters.

7.
ACS Sens ; 9(4): 1992-1999, 2024 04 26.
Artículo en Inglés | MEDLINE | ID: mdl-38536770

RESUMEN

The construction of assays is capable of accurately detecting cytokeratin-19 (CYFRA 21-1), which is critical for the rapid diagnosis of nonsmall cell lung cancer. In this work, a novel electrochemiluminescence (ECL) immunosensor based on the co-reaction promotion of luminol@Au@Ni-Co nanocages (NCs) as ECL probe by Ti3C2Tx MXene@TiO2-MoS2 hybrids as co-reaction accelerator was proposed to detect CYFRA 21-1. Ni-Co NCs, as a derivative of Prussian blue analogs, can be loaded with large quantities of Au NPs, luminol, and CYFRA 21-1 secondary antibodies due to their high specific surface area. To further improve the sensitivity of the developed ECL immunosensor, Ti3C2Tx MXene@TiO2-MoS2 hybrids were prepared by in situ growth of TiO2 nanosheets on highly conductive Ti3C2Tx MXene, and MoS2 was homogeneously grown on Ti3C2Tx MXene@TiO2 surfaces by the hydrothermal method. Ti3C2Tx MXene@TiO2-MoS2 hybrids possess excellent catalytic performance on the electro-redox of H2O2 generating more O2·- and obtaining optimal ECL intensity of the luminol/H2O2 system. Under the appropriate experimental conditions, the quantitative detection range of CYFRA 21-1 was from 0.1 pg mL-1 to 100 ng mL-1, and the limit of detection (LOD) was 0.046 pg mL-1. The present sensor has a lower LOD with a wider linear range, which provides a new analytical assay for the early diagnosis of small-cell-type lung cancer labels.


Asunto(s)
Antígenos de Neoplasias , Técnicas Biosensibles , Disulfuros , Técnicas Electroquímicas , Oro , Queratina-19 , Mediciones Luminiscentes , Luminol , Molibdeno , Titanio , Queratina-19/sangre , Queratina-19/inmunología , Titanio/química , Luminol/química , Molibdeno/química , Oro/química , Antígenos de Neoplasias/inmunología , Técnicas Electroquímicas/métodos , Humanos , Técnicas Biosensibles/métodos , Mediciones Luminiscentes/métodos , Inmunoensayo/métodos , Disulfuros/química , Límite de Detección , Níquel/química , Cobalto/química , Nanopartículas del Metal/química , Anticuerpos Inmovilizados/inmunología , Anticuerpos Inmovilizados/química
8.
Anal Chem ; 96(9): 3898-3905, 2024 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-38387028

RESUMEN

The effective applications of electrochemiluminescence (ECL) across various fields necessitate ongoing research into novel luminophores and ECL strategies. In this study, self-luminous flower-like nanocomposites (Eu-tcbpe-MOF) were prepared by coordination self-assembly using the aggregation-induced emission material 1,1,2,2-tetrakis(4-carboxyphenyl)ethylene (H4TCBPE) and Eu(III) ions as the precursors. Compared with the monomers and aggregates of H4TCBPE, Eu-tcbpe-MOF exhibits stronger ECL emission. Such enhanced electrochemiluminescence is due to coordination as the coordination-triggered electrochemiluminescence (CT-ECL) enhancement effect. In this study, a cubic-structured nanocomposite (Co9S8@Au@MoS2) was used as an efficient quencher, and a more sensitive ECL detection platform was achieved by two quenching mechanisms: resonance energy transfer and competitive consumption of coreactants. N,N-Diethylethanolamine (DBAE) was used as a coreactant, and DBAE has a faster electron transfer rate and stronger energy supply efficiency than the traditional anodoluminescent coreactant tripropylamine, which effectively improves the ECL signal intensity of Eu-tcbpe-MOF. Hence, a sandwich-type ECL immunosensor was prepared by employing a dual-quenching mechanism, utilizing Eu-tcbpe-MOF as the detection probe and Co9S8@Au@MoS2 as the quencher, achieving precise detection of carcinoembryonic antigen from 0.1 pg·mL-1 to 100 ng·mL-1 with a detection limit of 35.1 fg·mL-1.

9.
Talanta ; 272: 125780, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38359722

RESUMEN

Mercury ion (Hg2+) poses a serious threat to human health due to its high toxicity. In this study, a smartphone-based photoelectrochemical sensor based on oxygen vacancies (OVs) driven signal enhancement for mercury ion detection was designed. BiVO4-x/Bi2S3/AuNPs were combined with T-Hg2+-T recognition mode to construct a multi-sandwich photoelectrochemical sensor. On the one hand, the OVs can increase the adsorption of light by the materials and enhance the photocurrent response as well as the superconductivity of Au NPs to accelerate the charge transfer at the electrode interface. On the other hand, the multi-sandwich structure was exploited to increase the binding site of Hg2+, as well as the T-Hg2+-T structure for sensitive recognition of Hg2+ and signal amplification. The sensor showed good linearity for Hg2+ concentration in the range of 0.1 nM-1.0 µM with a detection limit of 4.8 pM (S/N = 3). Eventually the smartphone-based real-time detection sensor is expected to contribute to the future analysis of heavy metal ions.

10.
Chemphyschem ; 24(20): e202300536, 2023 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-37525230

RESUMEN

The electrocatalytic nitrate reduction reaction (NO3 - RR) enables the reduction of nitrate to ammonium ions under ambient conditions. It was considered as an alternative reaction for the production of ammonia (NH3 ) in recent years. In this paper, we report that the Fe doping CoS2 nanoarrays can effectively catalyze the formation of NH3 from nitrate (NO3 - ) under ambient conditions. This is mainly due to the increase of the NO3 - reaction active site by Fe doping and the porous nanostructure of the catalyst, which greatly improves the catalytic activity. Specifically, at -0.9 V vs. RHE, the NH3 yield rate (RNH3 ) of Fe-CoS2 /CC is 17.8×10-2  mmol h-1 cm-2 with Faraday Efficiency (FE) of 88.93 %. Besides, such catalyst shows good durability and catalytic stability, which provides the possibility for the future application of electrocatalytic NH3 production.

11.
J Hazard Mater ; 459: 132122, 2023 Oct 05.
Artículo en Inglés | MEDLINE | ID: mdl-37499488

RESUMEN

Lead ion (Pb2+) is one of the heavy metal contaminants within the environment, which can seriously affect biological health. Thus, it is very important to detect lead ions, especially exceeding the standard concentration (100 ng/mL). In this work, we have developed a photoelectrochemical (PEC) aptamer sensor with Z-scheme Fe2O3/g-C3N4 heterojunction as a substrate material for sensitive detection of Pb2+. Specifically, Fe2O3/g-C3N4 is employed as a substrate with a powerful and stable photocurrent response. Au and DNA-1 connected to the substrate material via the Au-S bond and increased the electron conduction. Marking DNA-2 with ZnO effectively reduced the light absorption intensity resulting in a lower photocurrent response. Surprisingly, the Pb2+ PEC sensor showed good linearity in the detection range of 62 pg/mL to 1 µg/mL with a detection limit as low as 7.9 pg/mL (S/N = 3). The sensor showed stable recovery and low relative standard deviation in real sample detection. Additionally, the sensor exhibited excellent stability, selectivity, and reproducibility. The reproducibility of the electrodes was evaluated, and the accuracy of the individual electrode current values was calculated to range from 0.5% to 2.71% with an RSD of 1.74%. Such PEC sensor guarantees to supply a brand-new approach to the detection of Pb2+.

13.
Microbiome ; 11(1): 30, 2023 02 21.
Artículo en Inglés | MEDLINE | ID: mdl-36810115

RESUMEN

BACKGROUND: Gut homeostasis, including intestinal immunity and microbiome, is essential for cognitive function via the gut-brain axis. This axis is altered in high-fat diet (HFD)-induced cognitive impairment and is closely associated with neurodegenerative diseases. Dimethyl itaconate (DI) is an itaconate derivative and has recently attracted extensive interest due to its anti-inflammatory effect. This study investigated whether intraperitoneal administration of DI improves the gut-brain axis and prevents cognitive deficits in HF diet-fed mice. RESULTS: DI effectively attenuated HFD-induced cognitive decline in behavioral tests of object location, novel object recognition, and nesting building, concurrent with the improvement of hippocampal RNA transcription profiles of genes associated with cognition and synaptic plasticity. In agreement, DI reduced the damage of synaptic ultrastructure and deficit of proteins (BDNF, SYN, and PSD95), the microglial activation, and neuroinflammation in the HFD-fed mice. In the colon, DI significantly lowered macrophage infiltration and the expression of pro-inflammatory cytokines (TNF-α, IL-1ß, IL-6) in mice on the HF diet, while upregulating the expression of immune homeostasis-related cytokines (IL-22, IL-23) and antimicrobial peptide Reg3γ. Moreover, DI alleviated HFD-induced gut barrier impairments, including elevation of colonic mucus thickness and expression of tight junction proteins (zonula occludens-1, occludin). Notably, HFD-induced microbiome alteration was improved by DI supplementation, characterized by the increase of propionate- and butyrate-producing bacteria. Correspondingly, DI increased the levels of propionate and butyrate in the serum of HFD mice. Intriguingly, fecal microbiome transplantation from DI-treated HF mice facilitated cognitive variables compared with HF mice, including higher cognitive indexes in behavior tests and optimization of hippocampal synaptic ultrastructure. These results highlight the gut microbiota is necessary for the effects of DI in improving cognitive impairment. CONCLUSIONS: The present study provides the first evidence that DI improves cognition and brain function with significant beneficial effects via the gut-brain axis, suggesting that DI may serve as a novel drug for treating obesity-associated neurodegenerative diseases. Video Abstract.


Asunto(s)
Disfunción Cognitiva , Dieta Alta en Grasa , Ratones , Animales , Eje Cerebro-Intestino , Obesidad/microbiología , Propionatos , Citocinas/genética , Butiratos , Ratones Endogámicos C57BL
14.
Anal Chem ; 94(50): 17396-17404, 2022 12 20.
Artículo en Inglés | MEDLINE | ID: mdl-36473066

RESUMEN

Lung cancer is a high-mortality cancer related to the concentration of neuron-specific enolase (NSE). In this work, a sandwich-type photoelectrochemical (PEC) immunosensor was constructed for ultrasensitive detection of NSE, which is based on iron trioxide/indium zinc cadmium sulfide (Fe2O3/Cd-ZnIn2.2Sy) as a sensing platform and Ag-modified polyaniline (Ag@PANI) as a signal amplification label. The 1D Fe2O3 porous nanorods with a large specific surface area were synthesized by calcination of Fe-MIL-88A and etching of NaOH. To improve the photocurrent response, the 3D architecture Cd-ZnIn2.2Sy was combined with the 1D Fe2O3 porous nanorods to form a 1D Fe2O3/3D Cd-ZnIn2.2Sy heterostructure. Specifically, the Fe2O3/Cd-ZnIn2.2Sy heterostructure with a good energy level matching (the two can form a stepped energy level matching, which accelerates the transfer rate of electrons) can improve the separation efficiency of electron-hole pairs (e-/h+) under visible light irradiation, which enhances the photocurrent response. Ag@PANI has a strong electron transport capability and can be used as a secondary antibody marker for the signal amplification of the immunosensor. The sensor exhibits a good linear detection range of 100 fg/mL to 100 ng/mL with a low detection limit of 33.5 fg/mL. Moreover, the constructed sandwich-type PEC immunosensor shows good performance and possesses excellent specificity, selectivity, and stability over a period of 4 weeks for NSE detection. With these excellent properties, the immunosensor can be extended to analyze and diagnose other disease biomarkers.


Asunto(s)
Técnicas Biosensibles , Técnicas Electroquímicas , Límite de Detección , Cadmio , Inmunoensayo , Fosfopiruvato Hidratasa
15.
J Natl Cancer Inst ; 114(11): 1437-1440, 2022 11 14.
Artículo en Inglés | MEDLINE | ID: mdl-36047830

RESUMEN

In 2018, the Cancer Therapy Evaluation Program (CTEP) at the US National Cancer Institute published new protocol template language that focused on organ function and prior and concurrent cancers in an effort to modernize eligibility criteria for cancer treatment trials. We conducted an analysis of CTEP-supported trials to evaluate the uptake and incorporation of the new language. The analysis included evaluation of 122 protocols approved in the years 2018-2020 for inclusion of the modernized eligibility criteria and consistency with new protocol template language related to 7 major eligibility criteria. These were cardiac function, liver function, kidney function, HIV status, prior and/or concurrent malignancies, treated and/or stable brain metastasis, and new and/or progressive brain metastases. Overall, CTEP trials evaluated in this period demonstrated that eligibility criteria were implemented to a relatively high degree ranging from a low of 54.1% for prior and/or concurrent malignancies to a high of 93.4% for eligibility criteria related to HIV infection. The findings demonstrate that modernized eligibility criteria can be successfully implemented but that consistent implementation requires sustained focused effort. As a result of these findings, CTEP began a new initiative in January 2022 that incorporates a specific review of eligibility criteria for new protocols to promote and improve consistency with the modernization effort.


Asunto(s)
Neoplasias Encefálicas , Infecciones por VIH , Estados Unidos , Humanos , National Cancer Institute (U.S.) , Infecciones por VIH/tratamiento farmacológico , Determinación de la Elegibilidad/métodos
16.
Anal Chem ; 94(36): 12368-12373, 2022 09 13.
Artículo en Inglés | MEDLINE | ID: mdl-36045488

RESUMEN

In this work, an antigen-down photoelectrochemical (PEC) immunosensor based on a signal polarity switching strategy for the detection of cytokeratin 19 fragment 21-1 (CYFRA21-1) was proposed. 3,4,9,10-Perylene tetracarboxylic acid (PTCA) is a conjugated organic dye containing five benzene nuclei, which has excellent film-forming and optical properties. PTCA sensitized by SnS2 can further improve the basal signal and the stability of the PEC immunosensor. Moreover, avidin-functionalized CuInS2 as a signal probe can convert the basal anodic photocurrent to a cathodic photocurrent. Therefore, the PEC sensor realized the photocurrent polarity conversion before and after labeling. With avidin-functionalized CuInS2, the polarity of the photocurrent was changed once CYFRA21-1 was detected. Therefore, the PEC immunosensor owns high sensitivity. The linear range of the immunosensor for the detection of CYFRA21-1 is 0.00001-500 ng·mL-1, and the detection limit is 3.5 fg·mL-1. The PEC immunosensor has good stability, high selectivity, and good repeatability. This work may provide a new way for the detection of CYFRA21-1 and other proteins.


Asunto(s)
Técnicas Biosensibles , Antígenos de Neoplasias , Avidina , Técnicas Electroquímicas , Inmunoensayo , Queratina-19 , Límite de Detección
17.
Nanotechnology ; 33(44)2022 Aug 15.
Artículo en Inglés | MEDLINE | ID: mdl-35882215

RESUMEN

The design and construction of active centres are key to exploring advanced electrocatalysts for oxygen evolution reaction (OER). In this work, we demonstrate thein situconstruction of point defects on CrOOH by Ni doping (Ni-CrOOH/NF). Compared with pure CrOOH/NF, Ni-CrOOH/NF showed enhanced OER activity. The effect of the amount of Ni introduced on the OER performance was investigated. Ni0.2-CrOOH/NF, the best introduction of Ni, uses a low overpotential of 253 mV to achieve a current density of 10 mA cm-2with a high turnover frequency of 0.27 s-1in 1.0 M NaOH. In addition, the electrocatalytic performance of Ni0.2-CrOOH/NF showed little deterioration after 1000-cycle cyclic voltammetry scanning. In the potentiostatic test, activity was stable for at least 20 h.

18.
Front Physiol ; 13: 810143, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-35295576

RESUMEN

Recent years have witnessed a rise in the morbidity of non-alcoholic fatty liver disease (NAFLD), in line with the global outbreak of obesity. However, effective intervention strategy against NAFLD is still unavailable. The present study sought to investigate the effect and mechanism of polyene phosphatidylcholine (PPC), a classic hepatoprotective drug, on NAFLD induced by high fat diet (HFD). We found that PPC intervention reduced the mass of liver, subcutaneous, epididymal, and brown fats in HFD mice. Furthermore, PPC supplementation significantly mitigated liver steatosis and improved glucose tolerance and insulin sensitivity in HFD mice, which was accompanied by declined levels of hepatic triglyceride, serum triglyceride, low density lipoprotein, aspartate aminotransferase, and alanine aminotransferase. Using transcriptome analysis, there were 1,789 differentially expressed genes (| fold change | ≥ 2, P < 0.05) including 893 upregulated genes and 896 downregulated genes in the HFD group compared to LC group. A total of 1,114 upregulated genes and 1,337 downregulated genes in HFD + PPC group were identified in comparison to HFD group. With the help of Gene Ontology (GO) analysis, these differentially expressed genes between HFD+PPC and HFD group were discovered related to "lipid metabolic process (GO: 0006629)," "lipid modification (GO: 0030258)," and "lipid homeostasis (GO: 0055088)". Though Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway analysis, we found pathways associated with hepatic homeostasis of metabolism and inflammation. Notably, the pathway "Non-alcoholic fatty liver disease (mmu04932)" (P-value = 0.00698) was authenticated in the study, which may inspire the potential mechanism of PPC to ameliorate NAFLD. The study also found that lipolysis, fatty acid oxidation, and lipid export associated genes were upregulated, while the genes in uptake of lipids and cholesterol synthesis were downregulated in the liver of HFD mice after PPC supplementation. Interestingly, PPC attenuated the metabolic inflammation via inhibiting pro-inflammatory macrophage in the livers of mice fed by HFD. In summary, this study demonstrates that PPC can ameliorate HFD-induced liver steatosis via reprogramming metabolic and inflammatory processes, which inspire clues for further clarifying the intervention mechanism of PPC against NAFLD.

19.
J Colloid Interface Sci ; 606(Pt 2): 1374-1379, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34492473

RESUMEN

The electrocatalytic reduction of nitrogen (N2) to ammonia (NH3) has broad prospects for green and sustainable NH3 production. Due to the electrocatalytic nitrogen reduction reaction (eNRR) performance of transition metal compound may be restricted with low yield rate, we develop transition metal interface engineering to improve the eNRR performance. Although the edge of MoS2 catalyst is active, the MoS2(001) surface is inert for N2 electroreduction. Through the hydrothermal and electrodeposition methods, Fe(OH)3 as N2 and H+ channels coated on MoS2 nanosheets array (MoS2@Fe(OH)3/CC) is synthesized. Such catalyst exhibits excellent eNRR performance in 0.1 M Na2SO4 with high Faradaic efficiency (2.76%) and NH3 yield rate (4.23 × 10-10 mol s-1 cm-2) at - 0.45 V (vs. RHE). This work may provide a new electrocatalyst synthesis pathway for artificial N2 fixation. Density functional theory calculations show that electrodeposition Fe(OH)3 can accelerate eNRR process rate of MoS2.

20.
J Colloid Interface Sci ; 609: 414-422, 2022 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-34906913

RESUMEN

Highly efficient catalysts are required to solve the intrinsically sluggish kinetics of oxygen evolution reaction (OER). Herein, chromium doped cobalt carbonate hydroxide nanowire array on Ni foam (Cr-CoCH/NF) has been synthesized for the enhancement of OER activity and stability. Compared with pure CoCH/NF, Cr0.2-CoCH/NF, the optimal doping of Cr, shows a low overpotential of 203 mV at the current density of 10 mA cm-2 and a small Tafel slope of 84 mV dec-1 in 1.0 M NaOH. In addition, there is little deterioration in electrocatalytic performance after 1000-cycle cyclic voltammetry and the high activity can be maintained over 25 h. Density functional theory calculations reveal the Cr doping can regulate the electronic structure of nearby Co active center to achieve great enhancement of OER activity.

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