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1.
Biochim Biophys Acta Rev Cancer ; 1879(5): 189125, 2024 Jun 06.
Artigo em Inglês | MEDLINE | ID: mdl-38851437

RESUMO

Tertiary lymphoid structures (TLS) can reflect cancer prognosis and clinical outcomes in various tumour tissues. Tumour-associated macrophages (TAMs) are indispensable components of the tumour microenvironment and play crucial roles in tumour development and immunotherapy. TAMs are associated with TLS induction via the modulation of the T cell response, which is a major component of the TLS. Despite their important roles in cancer immunology, the subtypes of TAMs that influence TLS and their correlation with prognosis are not completely understood. Here, we provide novel insights into the role of TAMs in regulating TLS formation. Furthermore, we discuss the prognostic value of these TAM subtypes and TLS, as well as the current antitumour therapies for inducing TLS. This study highlights an entirely new field of TLS regulation that may lead to the development of an innovative perspective on immunotherapy for cancer treatment.

2.
J Chem Inf Model ; 2024 Jun 11.
Artigo em Inglês | MEDLINE | ID: mdl-38861660

RESUMO

Hepatitis C virus (HCV) is a major cause of chronic liver disease and hepatocellular carcinoma. Antibody development efforts mainly revolve around HCV envelope glycoprotein 2 (E2), which mediates host cell entry by interacting with several cell surface receptors, including CD81. We still have limited knowledge about the structural ensembles and the dynamic behavior of both the CD81 binding sites and the glycans on E2. Here, multiple microsecond-long, all-atom molecular dynamics (MD) simulations, as well as a Markov state model (MSM), were performed to provide an atomistic perspective on the dynamic nature of E2 and its glycans. End-to-end accessibility analyses outline a complete overview of the vulnerabilities of the glycan shield of E2, which may be exploited in therapeutic efforts. Additionally, the Markov state model built from the simulation maps four metastable states for AS412 and three metastable states for the front layer in CD81 binding sites, while binding with HEPC3 would induce a conformation selection for both of them. Overall, this work presents hitherto unseen functional and structural insights into E2 and its glycan coat, providing a new theoretical foundation to control the conformational plasticity of E2 that could be harnessed for vaccine development.

3.
Nat Commun ; 15(1): 4679, 2024 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-38824163

RESUMO

Tungsten trioxide (WO3) has been recognized as the most promising photocatalyst for highly selective oxidation of methane (CH4) to formaldehyde (HCHO), but the origin of catalytic activity and the reaction manner remain controversial. Here, we take {001} and {110} facets dominated WO3 as the model photocatalysts. Distinctly, {001} facet can readily achieve 100% selectivity of HCHO via the active site mechanism whereas {110} facet hardly guarantees a high selectivity of HCHO along with many intermediate products via the radical way. In situ diffuse reflectance infrared Fourier transform spectroscopy, electron paramagnetic resonance and theoretical calculations confirm that the competitive chemical adsorption between CH4 and H2O and the different CH4 activation routes on WO3 surface are responsible for diverse CH4 oxidation pathways. The microscopic mechanism elucidation provides the guidance for designing high performance photocatalysts for selective CH4 oxidation.

4.
Child Abuse Negl ; 154: 106873, 2024 Jun 07.
Artigo em Inglês | MEDLINE | ID: mdl-38850751

RESUMO

BACKGROUND: Recent studies suggest that children and adolescents are at an increased risk of experiencing violence during the COVID-19 pandemic. However, there is limited knowledge about the prevalence of violence against children and adolescents across different regions in the world. OBJECTIVE: To estimate the pooled prevalence of violence against children and adolescents during the COVID-19 pandemic and explore how geographical and methodological factors explain the variation across studies. METHODS: We conducted a systematic search of MEDLINE, Embase, and PsycInfo databases for articles published from January 1, 2020 to October 1, 2022. The study protocol was pre-registered with PROSPERO (CRD42022338181). We included published and unpublished studies available in English that reported the prevalence of violence (e.g., physical, emotional, or sexual violence, neglect, bullying) against children and adolescents (age <18 years) during the pandemic. Data extraction followed the Preferred Reporting Items for Systematic Reviews and Meta-analysis (PRISMA) guidelines. A total of 2740 nonduplicate titles and abstracts were screened, and 217 full-text articles were reviewed for eligibility. RESULTS: Twenty-five studies with 66,637 participants met inclusion criteria. Based on random-effects meta-analysis, the pooled prevalence of violence against children and adolescents was 24 % (95%CI 18 %-30 %). The reported prevalence was higher in studies conducted in low- and middle-income countries compared to high-income countries. CONCLUSIONS: Over one in five children and adolescents globally reported ever experiencing violence during the COVID-19 pandemic. Our findings highlight the urgent need for effective child protection policies and interventions, as well as multisectoral collaboration, to reduce violence against children and adolescents.

5.
Child Adolesc Psychiatry Ment Health ; 18(1): 51, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702797

RESUMO

BACKGROUND: There is a high prevalence of childhood maltreatment among Chinese children and adolescents, but little is known about its impact on alcohol and tobacco use trajectories and how positive school and neighborhood environments moderate the associations. The objective of this study was to assess the association between multiple forms of childhood maltreatment and longitudinal alcohol and tobacco use trajectories, and to assess the possibility that perceived connections to school and neighborhood moderate these associations. METHODS: This longitudinal cohort study included 2594 adolescents (9 to 13 years) from a low-income rural area in China. Childhood exposure to abuse and neglect was assessed using the Childhood Trauma Questionnaire. Participants reported past-month alcohol and tobacco use at three time points over 1 year. RESULTS: Growth curve models revealed that childhood sexual abuse was associated with a higher risk of past-month drinking (OR = 1.53, 95% CI 1.19-2.03, p < 0.001) and smoking (OR = 1.82, 95% CI 1.30-2.55, p < 0.001). Neglect was associated with a higher risk of past-month drinking (OR = 1.52, 95% CI 1.06-1.90, p < 0.05) and smoking (OR = 2.02, 95% CI 1.34-3.02, p < 0.001). None of the maltreatment forms predicted a faster increase in either drinking or smoking. These associations were found independent of personal, family, and contextual characteristics. School and neighborhood connection moderated the association between physical abuse and past-month drinking, such that physical abuse was associated with a greater risk of drinking only for youth who perceived low school or neighborhood connections. CONCLUSIONS: Findings demonstrate the importance of early experiences of childhood maltreatment for adolescent alcohol and tobacco use. Enhancing school and neighborhood connectedness for physically abused youth may help protect them from alcohol use.

6.
PLoS One ; 19(5): e0300715, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38753625

RESUMO

With the onset of puberty, youth begin to choose their social environments and develop health-promoting habits, making it a vital period to study social and biological factors contextually. An important question is how pubertal development and behaviors such as physical activity and sleep may be differentially linked with youths' friendships. Cross-sectional statistical network models that account for interpersonal dependence were used to estimate associations between three measures of pubertal development and youth friendships at two large US schools drawn from the National Longitudinal Study of Adolescent to Adult Health. Whole-network models suggest that friendships are more likely between youth with similar levels of pubertal development, physical activity, and sleep. Sex-stratified models suggest that girls' friendships are more likely given a similar age at menarche. Attention to similar pubertal timing within friendship groups may offer inclusive opportunities for tailored developmental puberty education in ways that reduce stigma and improve health behaviors.


Assuntos
Comportamentos Relacionados com a Saúde , Puberdade , Humanos , Adolescente , Feminino , Puberdade/psicologia , Puberdade/fisiologia , Masculino , Estudos Transversais , Amigos/psicologia , Comportamento do Adolescente/psicologia , Estudos Longitudinais , Exercício Físico , Sono/fisiologia , Apoio Social , Rede Social
7.
Food Chem ; 454: 139712, 2024 May 20.
Artigo em Inglês | MEDLINE | ID: mdl-38795618

RESUMO

This work investigated structure-properties changes of reconstituted wheat A/B starch doughs under different ratios during dynamic thermal processing. Results indicated that a change in spatial conformation and aggregation structure of the starch-gluten system was induced with heating (30 °C-86 °C). Moderately increased B starch ratio can effectively fill the gluten network and improve starch-protein interactions, which promotes the free sulfhydryl group oxidation and results in the formation of more glutenin macropolymer; this contributes to a higher degree of cross-linking and stability to the gluten network matrix. This improvement is enhanced as the heating temperature is increased. Notably, the B starch ratio requires to be controlled within a suitable range (≤ 75%) to avoid aggregation and accumulation on the gluten matrix triggered by its excess. This work may provide insights and optimization for clarifying the on-demand regulation strategy of A/B starch in dough processing.

8.
Adv Sci (Weinh) ; : e2400790, 2024 May 13.
Artigo em Inglês | MEDLINE | ID: mdl-38741381

RESUMO

Heterotopic ossification (HO), the pathological formation of bone within soft tissues such as tendon and muscle, is a notable complication resulting from severe injury. While soft tissue injury is necessary for HO development, the specific molecular pathology responsible for trauma-induced HO remains a mystery. The previous study detected abnormal autophagy function in the early stages of tendon HO. Nevertheless, it remains to be determined whether autophagy governs the process of HO generation. Here, trauma-induced tendon HO model is used to investigate the relationship between autophagy and tendon calcification. In the early stages of tenotomy, it is observed that autophagic flux is significantly impaired and that blocking autophagic flux promoted the development of more rampant calcification. Moreover, Gt(ROSA)26sor transgenic mouse model experiments disclosed lysosomal acid dysfunction as chief reason behind impaired autophagic flux. Stimulating V-ATPase activity reinstated both lysosomal acid functioning and autophagic flux, thereby reversing tendon HO. This present study demonstrates that autophagy-lysosomal dysfunction triggers HO in the stages of tendon injury, with potential therapeutic targeting implications for HO.

9.
Water Res ; 257: 121700, 2024 Jun 15.
Artigo em Inglês | MEDLINE | ID: mdl-38705068

RESUMO

Sulfur-based denitrification is a promising technology in treatments of nitrate-contaminated wastewaters. However, due to weak bioavailability and electron-donating capability of elemental sulfur, its sulfur-to-nitrate ratio has long been low, limiting the support for dissimilatory nitrate reduction to ammonium (DNRA) process. Using a long-term sulfur-packed reactor, we demonstrate here for the first time that DNRA in sulfur-based system is not negligible, but rather contributes a remarkable 40.5 %-61.1 % of the total nitrate biotransformation for ammonium production. Through combination of kinetic experiments, electron flow analysis, 16S rRNA amplicon, and microbial network succession, we unveil a cryptic in-situ sulfur disproportionation (SDP) process which significantly facilitates DNRA via enhancing mass transfer and multiplying 86.7-210.9 % of bioavailable electrons. Metagenome assembly and single-copy gene phylogenetic analysis elucidate the abundant genomes, including uc_VadinHA17, PHOS-HE36, JALNZU01, Thiobacillus, and Rubrivivax, harboring complete genes for ammonification. Notably, a unique group of self-SDP-coupled DNRA microorganism was identified. This study unravels a previously concealed fate of DNRA, which highlights the tremendous potential for ammonium recovery and greenhouse gas mitigation. Discovery of a new coupling between nitrogen and sulfur cycles underscores great revision needs of sulfur-driven denitrification technology.


Assuntos
Compostos de Amônio , Nitratos , Nitrogênio , Enxofre , Enxofre/metabolismo , Compostos de Amônio/metabolismo , Nitratos/metabolismo , Nitrogênio/metabolismo , Desnitrificação , Reatores Biológicos , Águas Residuárias , Oxirredução , Filogenia , RNA Ribossômico 16S/genética
10.
Anal Chem ; 96(21): 8594-8603, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38718350

RESUMO

Solid-contact ion-selective electrodes (SC-ISEs) with ionophore-based polymer-sensitive membranes have been the major devices in wearable sweat sensors toward electrolyte analysis. However, the toxicity of ionophores in ion-selective membranes (ISMs), for example, valinomycin (K+ ion carrier), is a significant challenge, since the ISM directly contacts the skin during the tests. Herein, we report coating a hydrogel of graphene oxide-poly(vinyl alcohol) (GO-PVA) on the ISM to fabricate hydrogel-based SC-ISEs. The hydrogen bond interaction between GO sheets and PVA chains could enhance the mechanical strength through the formation of a cross-linking network. Comprehensive electrochemical tests have demonstrated that hydrogel-coated K+-SC-ISE maintains Nernstian response sensitivity, high selectivity, and anti-interference ability compared with uncoated K+-SC-ISE. A flexible hydrogel-based K+ sensing device was further fabricated with the integration of a solid-contact reference electrode, which has realized the monitoring of sweat K+ in real time. This work highlights the possibility of hydrogel coating for fabricating biocompatible wearable potentiometric sweat electrolyte sensors.

11.
Anal Chem ; 96(22): 9278-9284, 2024 Jun 04.
Artigo em Inglês | MEDLINE | ID: mdl-38768425

RESUMO

Antibody pharmaceuticals have become the most popular immunotherapeutic drugs and are often administered with low serum drug dosages. Hence, the development of a highly sensitive method for the quantitative assay of antibody levels is of great importance to individualized therapy. On the basis of the dual signal amplification by the glycan-initiated site-directed electrochemical grafting of polymer chains (glyGPC), we report herein a novel strategy for the amplified electrochemical detection of antibody pharmaceuticals. The target of interest was affinity captured by a DNA aptamer ligand, and then the glycans of antibody pharmaceuticals were decorated with the alkyl halide initiators (AHIs) via boronate cross-linking, followed by the electrochemical grafting of the ferrocenyl polymer chains from the glycans of antibody pharmaceuticals through the electrochemically controlled atom transfer radical polymerization (eATRP). As the glycans can be decorated with multiple AHIs and the grafted polymer chains are composed of tens to hundreds of electroactive tags, the glyGPC-based strategy permits the dually amplified electrochemical detection of antibody pharmaceuticals. In the presence of trastuzumab (Herceptin) as the target, the glyGPC-based strategy achieved a detection limit of 71.5 pg/mL. Moreover, the developed method is highly selective, and the results of the quantitative assay of trastuzumab levels in human serum are satisfactory. Owing to its uncomplicated operation and cost-effectiveness, the glyGPC-based strategy shows great promise in the amplified electrochemical detection of antibody pharmaceuticals.


Assuntos
Aptâmeros de Nucleotídeos , Técnicas Eletroquímicas , Trastuzumab , Técnicas Eletroquímicas/métodos , Humanos , Trastuzumab/química , Trastuzumab/sangue , Aptâmeros de Nucleotídeos/química , Limite de Detecção , Polissacarídeos/química , Técnicas Biossensoriais/métodos , Polímeros/química
12.
Artigo em Inglês | MEDLINE | ID: mdl-38625459

RESUMO

There is growing support for the dual-continua model of mental health, which emphasizes psychopathology and well-being as related but distinct dimensions. Yet, little is known about how these dimensions co-develop from childhood to early adolescence and what factors predict their different trajectories. The current study aimed to identify distinct patterns of mental health in Chinese early adolescents, focusing on both psychopathological symptoms (i.e., depressive symptoms and self-harm behaviors) and subjective well-being (i.e., life satisfaction and affect balance). This study also examined the contributions of school climate and future orientation to these trajectories. A total of 1,057 students (Mage = 11.88, SDage = 1.67; 62.1% boys) completed four assessments over two years, with six-month intervals. Using parallel-process latent class growth modeling, we identified four groups: Flourishing (32.5%), Languishing (43.8%), Troubled with Stable Depressive Symptoms (16.1%), and Troubled with Increasing Self-Harm Risk (7.6%). Furthermore, school climate and future orientation contributed to adolescents' membership in these trajectories, either independently or jointly. Specifically, higher levels of future orientation combined with higher school climate were associated with a lower likelihood of belonging to the Troubled with Increasing Self-Harm Risk trajectory, compared to the Flourishing group. Our findings identified four distinct mental health trajectories consistent with the dual-continua model, and demonstrated that the development of psychopathology and well-being were not always inversely related (e.g., the Languishing group). Adolescents with unique developmental profiles may benefit from tailored intervention strategies that build on the personal and environmental assets of the adolescent.

13.
Anal Bioanal Chem ; 2024 Apr 13.
Artigo em Inglês | MEDLINE | ID: mdl-38613683

RESUMO

The development of cost-effective and highly efficient electrocatalysts is critical to help electrochemical non-enzymatic sensors achieve high performance. Here, a new class of catalyst, Ru single atoms confined on Cu nanotubes as a single-atom alloy (Ru1Cu NTs), with a unique electronic structure and property, was developed to construct a novel electrochemical non-enzymatic glucose sensor for the first time. The Ru1Cu NTs with a diameter of about 24.0 nm showed a much lower oxidation potential (0.38 V) and 9.0-fold higher response (66.5 µA) current than Cu nanowires (Cu NWs, oxidation potential 0.47 V and current 7.4 µA) for glucose electrocatalysis. Moreover, as an electrochemical non-enzymatic glucose sensor, Ru1Cu NTs not only exhibited twofold higher sensitivity (54.9 µA mM-1 cm-2) and wider linear range (0.5-8 mM) than Cu NWs, but also showed a low detection limit (5.0 µM), excellent selectivity, and great stability. According to theoretical calculation results, the outstanding catalytic and sensing performance of Ru1Cu NTs could be ascribed to the upshift of the d-band center that helped promote glucose adsorption. This work presents a new avenue for developing highly active catalysts for electrochemical non-enzymatic sensors.

14.
Talanta ; 274: 125993, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38579422

RESUMO

Current potentiometric Cu2+ sensors mostly rely on polymer-membrane-based solid-contact ion-selective electrodes (SC-ISEs) that constitute ion-selective membranes (ISM) and solid contact (SC) for respective ion recognition and ion-to-electron transduction. Herein, we report an ISM-free Cu2+-SC-ISE based on Cu-Mn oxide (Cu1.4Mn1.6O4) as a bifunctional SC layer. The starting point is simplifying complex multi-interfaces for Cu2+-SC-ISEs. Specifically, ion recognition and signal transduction have been achieved synchronously by an ion-coupled-electron transfer of crystal ion transport and electron transfer of Mn4+/3+ in Cu1.4Mn1.6O4. The proposed Cu1.4Mn1.6O4 electrode discloses comparable sensitivity, response time, high selectivity and stability compared with present ISM-based potentiometric Cu2+ sensors. In addition, the Cu1.4Mn1.6O4 electrode also exhibits near Nernstian responses toward Cu2+ in natural water background. This work emphasizes an ISM-free concept and presents a scheme for the development of potentiometric Cu2+ sensors.

16.
Nat Biomed Eng ; 2024 Mar 15.
Artigo em Inglês | MEDLINE | ID: mdl-38491329

RESUMO

Dental calculi can cause gingival bleeding and periodontitis, yet the mechanism underlying the formation of such mineral build-ups, and in particular the role of the local microenvironment, are unclear. Here we show that the formation of dental calculi involves bacteria in local mature biofilms converting the DNA in neutrophil extracellular traps (NETs) from being degradable by the enzyme DNase I to being degradation resistant, promoting the nucleation and growth of apatite. DNase I inhibited NET-induced mineralization in vitro and ex vivo, yet plasma DNases were ineffective at inhibiting ectopic mineralization in the oral cavity in rodents. The topical application of the DNA-intercalating agent chloroquine in rodents fed with a dental calculogenic diet reverted NET DNA to its degradable form, inhibiting the formation of calculi. Our findings may motivate therapeutic strategies for the reduction of the prevalence of the deposition of bacteria-driven calculi in the oral cavity.

17.
Anal Chem ; 96(11): 4570-4579, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38441542

RESUMO

Ferroptosis, as a new form of regulated cell death, is implicated in various physiological and pathological processes. Developing a single probe for an independent analysis of multiple analytes related to ferroptosis can provide more accurate information and simplify the detection procedures, but it faces great challenges. In this work, we develop a fluorescent probe for the simultaneous detection of GSH through ratiometric fluorescence response and microviscosity via a fluorescence lifetime model. Based on the reversible Michael addition reaction between GSH and unsaturated C═C bond, the probe responds reversibly to GSH with a ratiometric fluorescence variation and a fast response time (t1/2 = 4.7 s). At the same time, the probe is sensitive to environmental viscosity by changing its fluorescence lifetimes. The probe was applied to monitor the drug-induced ferroptosis process through both the classical Xc-/GSH/GPX4- and DHODH-mediated defense mechanisms. We hope that the probe will provide a useful molecular tool for the real-time live-cell imaging of GSH dynamics, which is benefit to unveiling related physiological and pathological processes.


Assuntos
Ferroptose , Viscosidade , Corantes Fluorescentes/química , Microscopia de Fluorescência/métodos , Imagem Óptica , Glutationa/análise
18.
Anal Chem ; 96(14): 5437-5445, 2024 Apr 09.
Artigo em Inglês | MEDLINE | ID: mdl-38529794

RESUMO

The research on fluorescent rotors for viscosity has attracted extensive interest to better comprehend the close relationships of microviscosity variations with related diseases. Although scientists have made great efforts, fluorescent probes for cellular viscosity with both aggregation-induced emissions (AIEs) and large Stokes shifts to improve sensing properties have rarely been reported. Herein, we first report four new meso-C═N-substituted BODIPY-based rotors with large Stokes shifts, investigate their viscosity/AIE characteristics, and perform cellular imaging of the viscosity in subcellular organelles. Interestingly, the meso-C═N-phenyl group-substituted probe 6 showed an obvious 594 nm fluorescence enhancement in glycerol and a moderate 650 nm red AIE emission in water. Further, on attaching CF3 to the phenyl group, a similar phenomenon was observed for 7 with red-shifted emissions, attributed to the introduction of a phenyl group, which plays a key role in the red AIE emissions and large Stokes shifts. Comparatively, for phenyl-group-free probes, both the meso-C═N-trifluoroethyl group and thiazole-substituted probes (8 and 9) exhibited good viscosity-responsive properties, while no AIE was observed due to the absence of phenyl groups. For cellular experiments, 6 and 9 showed good lysosomal and mitochondrial targeting properties, respectively, and were further successfully used for imaging viscosity through the preincubation of monensin and lipopolysaccharide (LPS), indicating that C═N polar groups potentially work as rotatable moieties and organelle-targeting groups, and the targeting difference might be ascribed to increased charges of thiazole. Therefore, in this study, we investigated the structural relationships of four meso-C═N BODIPY-based rotors with respect to their viscosity/AIE characteristics, subcellular-targeting ability, and cellular imaging for viscosity, potentially serving as AIE fluorescent probes with large Stokes shifts for subcellular viscosity imaging.


Assuntos
Compostos de Boro , Corantes Fluorescentes , Organelas , Corantes Fluorescentes/química , Viscosidade , Tiazóis
19.
Talanta ; 274: 125990, 2024 Jul 01.
Artigo em Inglês | MEDLINE | ID: mdl-38552477

RESUMO

As a product of nonenzymatic glycation, glycated albumin (GA) is a promising serum marker for the short-term glycemic monitoring in patients with diabetes. On the basis of the boronate crosslinking (BCL)-enabled direct labeling of ferrocene (Fc) tags to the nonenzymatically glycated (NEG) sites, we report herein a novel aptamer-based ratiometric electrochemical (apt-REC) platform for the point-of-care (POC) assay of GA. This apt-REC platform is based on the recognition of GA proteins by the methylene blue (MB)-modified aptamer receptors and the labeling of the Fc tags to the NEG sites via the BCL. Using MB as the reference tag and Fc as the quantification tag, the ratio of the oxidation currents (i.e., IFc/IMB) can serve as the yardstick for the ratiometric assay of GA. Due to the presence of tens of the NEG sites, each GA protein can be labeled with tens of quantification tags, permitting the amplified assay in a simple, time-saving, and low-cost manner. The ratiometric signal exhibited a good linear response over the range from 0.1 to 100 µg/mL, with a detection limit of 45.5 ng/mL. In addition to the superior reproducibility and robustness, this apt-REC platform is highly selective (capable of discriminating GA against human serum albumin (HSA)) and applicable to GA assay in serum samples. Due to its low cost, high reproducibility and robustness, simple operation, and high sensitivity and selectivity, this apt-REC platform holds great promise in the POC assay of GA for diabetes management.


Assuntos
Ácidos Borônicos , Técnicas Eletroquímicas , Albumina Sérica Glicada , Humanos , Aptâmeros de Nucleotídeos/química , Técnicas Biossensoriais/métodos , Ácidos Borônicos/química , Reagentes de Ligações Cruzadas/química , Técnicas Eletroquímicas/métodos , Produtos Finais de Glicação Avançada/química , Limite de Detecção , Albumina Sérica/química , Albumina Sérica/análise , Albumina Sérica Humana/química , Albumina Sérica Humana/análise
20.
Adv Sci (Weinh) ; 11(17): e2309163, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38425147

RESUMO

Tuning the crystal phase of alloy nanocrystals (NCs) offers an alternative way to improve their electrocatalytic performance, but, how heterometals diffuse and form ordered-phase remains unclear. Herein, for the first time, the mechanism for forming tetrametallic ordered-phase nanoplates (NPLs) is unraveled. The observations reveal that the intermetallic ordered-phase nucleates through crystallinity alteration of the seeds and then propagates by reentrant grooves. Notably, the reentrant grooves act as intermediate NCs for ordered-phase, eventually forming intermetallic PdCuIrCo NPLs. These NPLs substantially outperform for oxygen evolution reaction (221 mV at 10 mA cm-2) and hydrogen evolution reaction (19 mV at 10 mA cm-2) compared to commercial Ir/C and Pd/C catalysts in acidic media. For OER at 1.53 V versus RHE, the PdCuIrCo/C exhibits an enhanced mass activity of 9.8 A mg-1 Pd+Ir (about ten times higher) than Ir/C. For HER at -0. 2 V versus RHE, PdCuIrCo/C shows a remarkable mass activity of 1.06 A mg-1 Pd+Ir, which is three-fold relative to Pd/C. These improvements can be ascribed to the intermetallic ordered-structure with high-valence Ir sites and tensile-strain. This approach enabled the realization of a previously unobserved mechanism for ordered-phase NCs. Therefore, this strategy of making ordered-phase NPLs can be used in diverse heterogeneous catalysis.

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