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1.
Nat Commun ; 15(1): 2950, 2024 Apr 05.
Artigo em Inglês | MEDLINE | ID: mdl-38580635

RESUMO

Seawater electroreduction is attractive for future H2 production and intermittent energy storage, which has been hindered by aggressive Mg2+/Ca2+ precipitation at cathodes and consequent poor stability. Here we present a vital microscopic bubble/precipitate traffic system (MBPTS) by constructing honeycomb-type 3D cathodes for robust anti-precipitation seawater reduction (SR), which massively/uniformly release small-sized H2 bubbles to almost every corner of the cathode to repel Mg2+/Ca2+ precipitates without a break. Noticeably, the optimal cathode with built-in MBPTS not only enables state-of-the-art alkaline SR performance (1000-h stable operation at -1 A cm-2) but also is highly specialized in catalytically splitting natural seawater into H2 with the greatest anti-precipitation ability. Low precipitation amounts after prolonged tests under large current densities reflect genuine efficacy by our MBPTS. Additionally, a flow-type electrolyzer based on our optimal cathode stably functions at industrially-relevant 500 mA cm-2 for 150 h in natural seawater while unwaveringly sustaining near-100% H2 Faradic efficiency. Note that the estimated price (~1.8 US$/kgH2) is even cheaper than the US Department of Energy's goal price (2 US$/kgH2).

2.
Adv Mater ; : e2401221, 2024 Apr 02.
Artigo em Inglês | MEDLINE | ID: mdl-38563723

RESUMO

Renewable electricity-powered nitrate/carbon dioxide co-reduction reaction toward urea production paves an attractive alternative to industrial urea processes and offers a clean on-site approach to closing the global nitrogen cycle. However, its large-scale implantation is severely impeded by challenging C-N coupling and requires electrocatalysts with high activity/selectivity. Here, cobalt-nanoparticles anchored on carbon nanosheet (Co NPs@C) are proposed as a catalyst electrode to boost yield and Faradaic efficiency (FE) toward urea electrosynthesis with enhanced C-N coupling. Such Co NPs@C renders superb urea-producing activity with a high FE reaching 54.3% and a urea yield of 2217.5 µg h-1 mgcat. -1, much superior to the Co NPs and C nanosheet counterparts, and meanwhile shows strong stability. The Co NPs@C affords rich catalytically active sites, fast reactant diffusion, and sufficient catalytic surfaces-electrolyte contacts with favored charge and ion transfer efficiencies. The theoretical calculations reveal that the high-rate formation of *CO and *NH2 intermediates is crucial for facilitating urea synthesis.

3.
Food Chem ; 447: 139018, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-38503067

RESUMO

Developing an accurate, cost-effective, reliable, and stable glucose detection sensor for the food industry poses a significant yet challenging endeavor. Herein, we present a silver nanoparticle-decorated titanium dioxide nanoribbon array on titanium plate (Ag@TiO2/TP) as an efficient electrode for non-enzymatic glucose detection in alkaline environments. Electrochemical evaluations of the Ag@TiO2/TP electrode reveal a broad linear response range (0.001 mM - 4 mM), high sensitivity (19,106 and 4264 µA mM-1 cm-2), rapid response time (6 s), and a notably low detection limit (0.18 µM, S/N = 3). Moreover, its efficacy in measuring glucose in beverage samples shows its practical applicability. The impressive performance and structural benefits of the Ag@TiO2/TP electrode highlight its potential in advancing electrochemical sensors for small molecule detection.


Assuntos
Técnicas Biossensoriais , Nanopartículas Metálicas , Nanotubos de Carbono , Nanopartículas Metálicas/química , Técnicas Eletroquímicas , Prata , Glucose/química , Eletrodos
4.
J Control Release ; 369: 39-52, 2024 Mar 21.
Artigo em Inglês | MEDLINE | ID: mdl-38508523

RESUMO

The emergence of multidrug-resistant bacteria along with their resilient biofilms necessitates the development of creative antimicrobial remedies. We designed versatile fluorinated polymer micelles with surface-charge-switchable properties, demonstrating enhanced efficacy against Methicillin-Resistant Staphylococcus Aureus (MRSA) in planktonic and biofilm states. Polymethacrylate diblock copolymers with pendant fluorocarbon chains and carboxyl betaine groups were prepared using reversible addition-fragmentation chain transfer polymerization. Amphiphilic fluorinated copolymers self-assembled into micelles, encapsulating ciprofloxacin in their cores (CIP@FCBMs) for antibacterial and antibiofilm applications. As a control, fluorine-free copolymer micelles loaded with ciprofloxacin (CIP@BCBMs) were prepared. Although both CIP@FCBMs and CIP@BCBMs exhibited pH-responsive surface charges and lipase-triggered drug release, CIP@FCBMs exhibited powerful antimicrobial and antibiofilm activities in vitro and in vivo, attributed to superior serum stability, higher drug loading, enhanced fluorination-facilitated cellular uptake, and lipase-triggered drug release. Collectively, reversing surface charge, on-demand antibiotic release, and fluorination-mediated nanoparticles hold promise for treating bacterial infections and biofilms.

5.
Small ; : e2400141, 2024 Mar 03.
Artigo em Inglês | MEDLINE | ID: mdl-38431944

RESUMO

Seawater electrolysis holds tremendous promise for the generation of green hydrogen (H2 ). However, the system of seawater-to-H2 faces significant hurdles, primarily due to the corrosive effects of chlorine compounds, which can cause severe anodic deterioration. Here, a nickel phosphide nanosheet array with amorphous NiMoO4 layer on Ni foam (Ni2 P@NiMoO4 /NF) is reported as a highly efficient and stable electrocatalyst for oxygen evolution reaction (OER) in alkaline seawater. Such Ni2 P@NiMoO4 /NF requires overpotentials of just 343 and 370 mV to achieve industrial-level current densities of 500 and 1000 mA cm-2 , respectively, surpassing that of Ni2 P/NF (470 and 555 mV). Furthermore, it maintains consistent electrolysis for over 500 h, a significant improvement compared to that of Ni2 P/NF (120 h) and Ni(OH)2 /NF (65 h). Electrochemical in situ Raman spectroscopy, stability testing, and chloride extraction analysis reveal that is situ formed MoO4 2- /PO4 3- from Ni2 P@NiMoO4 during the OER test to the electrode surface, thus effectively repelling Cl- and hindering the formation of harmful ClO- .

6.
Small ; : e2311431, 2024 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-38366284

RESUMO

Renewable electricity-driven seawater splitting presents a green, effective, and promising strategy for building hydrogen (H2 )-based energy systems (e.g., storing wind power as H2 ), especially in many coastal cities. The abundance of Cl- in seawater, however, will cause severe corrosion of anode catalyst during the seawater electrolysis, and thus affect the long-term stability of the catalyst. Herein, seawater oxidation performances of NiFe layered double hydroxides (LDH), a classic oxygen (O2 ) evolution material, can be boosted by employing tungstate (WO4 2- ) as the intercalated guest. Notably, insertion of WO4 2- to LDH layers upgrades the reaction kinetics and selectivity, attaining higher current densities with ≈100% O2 generation efficiency in alkaline seawater. Moreover, after a 350 h test at 1000 mA cm-2 , only trace active chlorine can be detected in the electrolyte. Additionally, O2 evolution follows lattice oxygen mechanism on NiFe LDH with intercalated WO4 2- .

7.
J Colloid Interface Sci ; 662: 596-603, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38367577

RESUMO

Seawater electrolysis is gaining recognition as a promising method for hydrogen production. However, severe anode corrosion caused by the high concentration of chloride ions (Cl-) poses a challenge for the long-term oxygen evolution reaction. Herein, an anti-corrosion strategy of oxalate anions intercalation in NiFe layered double hydroxide on nickel foam (NiFe-C2O42- LDH/NF) is proposed. The intercalation of these highly negatively charged C2O42- serves to establish electrostatic repulsion and impede Cl- adsorption. In alkaline seawater, NiFe-C2O42- LDH/NF requires an overpotential of 337 mV to gain the large current density of 1000 mA cm-2 and operates continuously for 500 h. The intercalation of C2O42- is demonstrated to significantly boost the activity and stability of NiFe LDH-based materials during alkaline seawater oxidation.

8.
iScience ; 27(1): 108736, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38269101

RESUMO

Herein, a hierarchical NiTe@NiFe-LDH core-shell array on Ni foam (NiTe@NiFe-LDH/NF) demonstrates its effectiveness for oxygen evolution reaction (OER) in alkaline seawater electrolyte. This NiTe@NiFe-LDH/NF array showcases remarkably low overpotentials of 277 mV and 359 mV for achieving current densities of 100 and 500 mA cm-2, respectively. Also, it shows a low Tafel slope of 68.66 mV dec-1. Notably, the electrocatalyst maintains robust stability over continuous electrolysis for at least 50 h at 100 mA cm-2. The remarkable performance and hierarchical structure advantages of NiTe@NiFe-LDH/NF offer innovative insights for designing efficient seawater oxidation electrocatalysts.

9.
iScience ; 27(1): 108738, 2024 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-38260173

RESUMO

High-purity hydrogen produced by water electrolysis has become a sustainable energy carrier. Due to the corrosive environments and strong oxidizing working conditions, the main challenge faced by acidic water oxidation is the decrease in the activity and stability of anodic electrocatalysts. To address this issue, efficient strategies have been developed to design electrocatalysts toward acidic OER with excellent intrinsic performance. Electronic structure modification achieved through defect engineering, doping, alloying, atomic arrangement, surface reconstruction, and constructing metal-support interactions provides an effective means to boost OER. Based on introducing OER mechanism commonly present in acidic environments, this review comprehensively summarizes the effective strategies for regulating the electronic structure to boost the activity and stability of catalytic materials. Finally, several promising research directions are discussed to inspire the design and synthesis of high-performance acidic OER electrocatalysts.

10.
Small ; : e2311055, 2024 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-38295001

RESUMO

Through inducing interlayer anionic ligands and functionally modifying conductive carbon-skeleton on the transition metal chalcogenides (TMCs) parent to achieve atomic-level defect-manipulation and nanoscopic-level architecture design is of great significance, which can broaden interlayer distance, optimize electronic structure, and mitigate structural deformation to endow high-efficiency battery performance of TMCs. Herein, an intriguing 3D biconcave hollow-tyre-like anode constituted by carbon-packaged defective-rich SnSSe nanosheet grafting onto Aspergillus niger spores-derived hollow-carbon (ANDC@SnSSe@C) is reported. Systematically experimental investigations and theoretical analyses forcefully demonstrate the existence of anion Se ligand and outer-carbon all-around encapsulation on the ANDC@SnSSe@C can effectively yield abundant structural defects and Na+ -reactivity sites, accelerate rapid ion migration, widen interlayer spacing, as well as relieve volume expansion, thus further resolving the critical issues throughout the charge-discharge processes. As anticipated, as-fabricated ANDC@SnSSe@C anode contributes extraordinary reversible capacity, wonderful cyclic lifespan with 83.4% capacity retention over 2000 cycles at 20.0 A g-1 , and exceptional rate capability. A series of correlated kinetic investigations and ex situ characterizations deeply reveal the underlying springheads for the ion-transport kinetics, as well as synthetically elucidate phase-transformation mechanism of the ANDC@SnSSe@C. Furthermore, the ANDC@SnSSe@C-based sodium ion full cell and hybrid capacitor offer high-capacity contribution and remarkable energy-density output, indicative of its great practicability.

11.
Small ; 20(13): e2307294, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37963858

RESUMO

The pursuit of stable and efficient electrocatalysts toward seawater oxidation is of great interest, yet it poses considerable challenges. Herein, the utilization of Cr-doped CoFe-layered double hydroxide nanosheet array is reported on nickel-foam (Cr-CoFe-LDH/NF) as an efficient electrocatalyst for oxygen evolution reaction in alkaline seawater. The Cr-CoFe-LDH/NF catalyst can achieve current densities of 500 and 1000 mA cm -2 with remarkably low overpotentials of only 334 and 369 mV, respectively. Furthermore, it maintains at least 100 h stability when operated at 500 mA cm-2.

12.
Immunology ; 171(2): 170-180, 2024 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-37735978

RESUMO

NLR family pyrin domain containing 2 (NLRP2) is a novel member of the Nod-like receptor (NLR) family. However, our understanding of NLRP2 has long been ambiguous. NLRP2 may have a role in the innate immune response, but its 'specific' functions remain controversial. Although NLRP2 can initiate inflammasome and promote inflammation, it can also downregulate inflammatory signals. Additionally, NLRP2 has been reported to function in the reproductive system and shows high expression in the placenta. However, the exact role of NLRP2 in the reproductive system is unclear. Here, we highlight the most current progress on NLRP2 in inflammasome activation, effector function and regulation of nuclear factor-κB. And we discuss functions of NLRP2 in inflammatory diseases, reproductive disorders and the potential implication of NLRP2 in human diseases.


Assuntos
Proteínas Adaptadoras de Transdução de Sinal , Inflamassomos , Humanos , Inflamassomos/metabolismo , Proteínas Adaptadoras de Transdução de Sinal/metabolismo , Proteínas Reguladoras de Apoptose/metabolismo , NF-kappa B/metabolismo , Inflamação/metabolismo , Proteína 3 que Contém Domínio de Pirina da Família NLR/metabolismo
13.
Angew Chem Int Ed Engl ; 63(1): e202316522, 2024 Jan 02.
Artigo em Inglês | MEDLINE | ID: mdl-37994225

RESUMO

Seawater electrolysis is an attractive way of making H2 in coastal areas, and NiFe-based materials are among the top options for alkaline seawater oxidation (ASO). However, ample Cl- in seawater can severely corrode catalytic sites and lead to limited lifespans. Herein, we report that in situ carbon oxyanion self-transformation (COST) from oxalate to carbonate on a monolithic NiFe oxalate micropillar electrode allows safeguard of high-valence metal reaction sites in ASO. In situ/ex situ studies show that spontaneous, timely, and appropriate COST safeguards active sites against Cl- attack during ASO even at an ampere-level current density (j). Our NiFe catalyst shows efficient and stable ASO performance, which requires an overpotential as low as 349 mV to attain a j of 1 A cm-2 . Moreover, the NiFe catalyst with protective surface CO3 2- exhibits a slight activity degradation after 600 h of electrolysis under 1 A cm-2 in alkaline seawater. This work reports effective catalyst surface design concepts at the level of oxyanion self-transformation, acting as a momentous step toward defending active sites in seawater-to-H2 conversion systems.

14.
Chem Commun (Camb) ; 59(72): 10805-10808, 2023 Sep 07.
Artigo em Inglês | MEDLINE | ID: mdl-37594506

RESUMO

A 3D cauliflower-like Ni foam on titanium plate (Ni foam/TP) shows high electrocatalytic performance for ambient ammonia (NH3) synthesis via nitrite (NO2-) reduction. In 0.1 M phosphate-buffered saline solution with 0.1 M NO2-, such Ni foam/TP attains a high NH3 Faradaic efficiency (FE) of 95.9% and a large NH3 yield of 742.7 µmol h-1 cm-2 at -0.8 V. Its Zn-NO2- battery offers a high power density of 6.2 mW cm-2 and an NH3 FE of 90.1%.

15.
Chem Commun (Camb) ; 59(59): 9017-9028, 2023 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-37409494

RESUMO

Electrochemical CO2 reduction into value-added chemicals represents an attractive and promising approach to capitalize on the abundant CO2 present in the atmosphere. This reaction, however, is hampered by low energy efficiency and selectivity owing to competition from hydrogen evolution reaction and multiple-electron transfer processes. Therefore, there is a pressing need to develop efficient yet cost-effective electrocatalysts to facilitate practical applications. Sn-based electrocatalysts have gained increasing attention in this active field due to their outstanding merits such as abundance, non-toxicity, and environmental friendliness. This review provides a comprehensive overview of recent advances in Sn-based catalysts for the CO2 reduction reaction (CO2RR), beginning with a brief introduction to the CO2RR mechanism. Subsequently, the CO2RR performance of various Sn-based catalysts with different structures is discussed. The article concludes by addressing the existing challenges and offering personal perspectives on the future prospects in this exciting research area.

16.
Chem Commun (Camb) ; 59(64): 9750-9753, 2023 Aug 08.
Artigo em Inglês | MEDLINE | ID: mdl-37482797

RESUMO

The presence of chlorine species in seawater can cause severe anode corrosion, highlighting the critical need for the design of efficient and robust electrocatalysts towards the oxygen evolution reaction (OER) for hydrogen production. Herein, we present a chromium doped cobalt carbonate hydroxide nanowire array on nickel foam (Cr-CoCH/NF) as an effective OER electrocatalyst in seawater. In alkaline conditions, Cr-CoCH/NF exhibits a low overpotential of 450 mV to achieve 500 mA cm-2, surpassing that of CoCH/NF (614 mV). Additionally, it demonstrates 200 h of continuous oxygen evolution testing.

17.
Asian J Pharm Sci ; 18(3): 100810, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-37274927

RESUMO

The appearance of multidrug-resistant bacteria and the formation of bacterial biofilms have necessitated the development of alternative antimicrobial therapeutics. Antibiotics conjugated with or embedded in nano-drug carriers show a great potential and advantage over free drugs, but the mass proportion of carriers generally exceeds 90% of the nano-drug, resulting in low drug loading and limited therapeutic output. Herein, we fabricated a nanocarrier using antibiotics as the building blocks, minimizing the use of carrier materials, significantly increasing the drug loading content and treatment effect. Firstly, we conjugated betaine carboxylate with ciprofloxacin (CIP) through an ester bond to form the amphiphilic conjugate (CIP-CB), which self-assembled into micelles (CIP-CBMs) in aqueous solutions, with a CIP loading content as high as 65.4% and pH-induced surface charge reversal properties. Secondly, a model photosensitizer (5, 10, 15, 20-tetraphenylporphyrin (TPP)) was encapsulated in CIP-CBMs, generating infection-targeted photodynamic/antibiotic combined nanomedicines (denoted as TPP@CIP-CBMs). Upon accumulation at infection sites or in deep bacterial biofilms, the ester bond between the betaine carboxylate and CIP is cleaved to release free TPP and CIP, leading to a synergetic antibacterial and antibiofilm activity in vitro and in vivo.

18.
Acta Biomater ; 166: 627-639, 2023 08.
Artigo em Inglês | MEDLINE | ID: mdl-37220819

RESUMO

A new counterion-induced small-molecule micelle (SM) with surface charge-switchable activities for methicillin-resistant Staphylococcus aureus (MRSA) infections is proposed. The amphiphilic molecule formed by zwitterionic compound and the antibiotic ciprofloxacin (CIP), via a "mild salifying reaction" of the amino and benzoic acid groups, can spontaneously assemble into counterion-induced SMs in water. Through vinyl groups designed on zwitterionic compound, the counterion-induced SMs could be readily cross-linked using mercapto-3, 6-dioxoheptane by click reaction, to create pH-sensitive cross-linked micelles (CSMs). Mercaptosuccinic acid was also decorated on the CSMs (DCSMs) by the same click reaction to afford charge-switchable activities, resulting in CSMs that were biocompatible with red blood cells and mammalian cells in normal tissues (pH 7.4), while having strong retention to negatively charged bacterial surfaces at infection sites, based on electrostatic interaction (pH 5.5). As a result, the DCSMs could penetrate deep into bacterial biofilms and then release drugs in response to the bacterial microenvironment, effectively killing the bacteria in the deeper biofilm. The new DCSMs have several advantages such as robust stability, a high drug loading content (∼ 30%), easy fabrication, and good structural control. Overall, the concept holds promise for the development of new products for clinical application. STATEMENT OF SIGNIFICANCE: We fabricated a new counterion-induced small-molecule micelle with surface charge-switchable activities (DCSMs) for methicillin-resistant Staphylococcus aureus (MRSA) infections. Compared with reported covalent systems, the DCSMs not only have improved stability, high drug loading content (∼ 30%), and good biosafety, but also have the environmental stimuli response, and antibacterial activity of the original drugs. As a result, the DCSMs exhibited enhanced antibacterial activities against MRSA both in vitro and in vivo. Overall, the concept holds promise for the development of new products for clinical application.


Assuntos
Staphylococcus aureus Resistente à Meticilina , Infecções Estafilocócicas , Animais , Antibacterianos/química , Micelas , Infecções Estafilocócicas/tratamento farmacológico , Infecções Estafilocócicas/microbiologia , Biofilmes , Testes de Sensibilidade Microbiana , Mamíferos
19.
Mol Pharm ; 19(9): 3187-3198, 2022 09 05.
Artigo em Inglês | MEDLINE | ID: mdl-35939328

RESUMO

As the most common subtype in ovarian malignancies, high-grade serous ovarian cancer (HGSOC) made less therapeutic progress in past decades due to the lack of effective drug-able targets. Herein, an effective linoleic acid (LA) and glucosamine (GlcN) hybrid (LA-GlcN) was synthesized for the treatment of HGSOC. The GlcN was introduced to recognize the glucose transporter 1 (GLUT 1) overexpressed in tumor cells to enhance the uptake of LA-GlcN, and the unsaturated LA was employed to trigger ferroptosis by iron-dependent lipid peroxidation. Since the iron content of HGSOC was ∼5 and 2 times, respectively, higher than that of the normal ovarian cells and low-grade serous ovarian cancer cells, these excess irons make them a good target to enhance the ferroptosis of LA-GlcN. The in vitro study demonstrated that LA-GlcN could selectively kill HGSOC cells without affecting normal cells; the in vivo study revealed that LA-GlcN at the dose of 50 mg kg-1 achieved a comparable tumor inhibition as doxorubicin hydrochloride (4 mg kg-1) while the overall survival of mice was extended largely due to the low toxicity, and when the dose was increased to 100 mg kg-1, the therapeutic outcomes could be improved further. This dietary hybrid which targets the excess endogenous iron to activate ferroptosis represents a promising drug for HGSOC treatment.


Assuntos
Cistadenocarcinoma Seroso , Ferroptose , Neoplasias Ovarianas , Animais , Feminino , Glucosamina , Humanos , Ferro , Ácido Linoleico/uso terapêutico , Camundongos , Neoplasias Ovarianas/tratamento farmacológico , Neoplasias Ovarianas/patologia
20.
RSC Adv ; 12(10): 6076-6082, 2022 Feb 16.
Artigo em Inglês | MEDLINE | ID: mdl-35424584

RESUMO

Drug delivery systems (DDSs) show great application prospects in tumor therapy. So far, physical encapsulation and covalent grafting were the two most common strategies for the construction of DDSs. However, physical encapsulation-based DDSs usually suffered from low drug loading capacity and poor stability, and covalent grafting-based DDSs might reduce the activity of original drug, which greatly limited their clinical application. Therefore, it is of great research value to design a new DDS with high drug loading capacity, robust stability, and original drug activity. Herein, we report a super-amphiphile based drug delivery system (HBS-DDS) through self-assembly induced by hydrogen bonds between amino-substituted N-heterocycles of the 1,3,5-triazines and hydrophilic carmofur (HCFU). The resulting HBS-DDS had a high drug loading capacity (38.1%) and robust stability. In addition, the drug delivery system exhibited pH-triggered size change and release of drugs because of the pH responsiveness of hydrogen bonds. In particular, the anticancer ability test showed that the HBS-DDS could be efficiently ingested by tumor cells, and its half-maximal inhibitory concentration (IC50 = 3.53 µg mL-1) for HeLa cells was close to that of free HCFU (IC50 = 5.54 µg mL-1). The hydrogen bond-based DDS represents a potential drug delivery system in tumor therapy.

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