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1.
PNAS Nexus ; 3(4): pgae140, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38628599

RESUMO

Specific human leukocyte antigen (HLA) polymorphisms combined with certain drug administration strongly correlate with skin eruption. Abacavir hypersensitivity (AHS), which is strongly associated with HLA-B*57:01, is one of the most representative examples. Conventionally, HLA transmits immunological signals via interactions with T cell receptors on the cell surface. This study focused on HLA-mediated intracellular reactions in keratinocytes that might determine the onset of skin immunotoxicity by drug treatments. Abacavir exposure resulted in keratinocytes expressing HLA-B*57:01 exhibiting endoplasmic reticulum (ER) stress responses, such as immediate calcium release into the cytosol and enhanced HSP70 expression. In contrast, keratinocytes expressing HLA-B*57:03 (closely related to HLA-B*57:01) did not show these changes. This indicated that HLA-B*57:01 has a specific intracellular response to abacavir in keratinocytes in the absence of lymphocytes. Furthermore, abacavir exposure in HLA-B*57:01-expressing keratinocytes elevated the expression of cytokines/chemokines such as interferon-γ, interleukin-1ß, and CCL27, and induced T lymphoblast migration. These effects were suppressed by ER stress relief using 4-phenylbutyrate (4-PB). HLA-B*57:01-transgenic mice also exhibited ER stress in epidermal areas following abacavir administration, and abacavir-induced skin toxicity was attenuated by the administration of 4-PB. Moreover, abacavir bound to HLA-B*57:01 within cells and its exposure led to HLA-B*57:01 protein aggregation and interaction with molecular chaperones in the ER of keratinocytes. Our results underscore the importance of HLA-mediated intracellular stress responses in understanding the onset of HLA-B*57:01-mediated AHS. We provide the possibility that the intracellular behavior of HLA is crucial for determining the onset of drug eruptions.

2.
J Clin Pharmacol ; 2024 Apr 17.
Artigo em Inglês | MEDLINE | ID: mdl-38632826

RESUMO

Tezepelumab is a human monoclonal antibody that blocks the activity of thymic stromal lymphopoietin. This analysis assessed the suitability of a fixed-dose regimen of tezepelumab 210 mg every 4 weeks (Q4W) in adults and adolescents with severe, uncontrolled asthma. A population pharmacokinetic model was developed using data from 1368 patients with asthma or healthy participants enrolled in 8 clinical studies (phases 1-3). Tezepelumab exposure-efficacy relationships were analyzed in the phase 3 NAVIGATOR study (NCT03347279), using asthma exacerbation rates over 52 weeks and changes in pre-bronchodilator forced expiratory volume in 1 s at week 52. Tezepelumab pharmacokinetics were well characterized by a 2-compartment linear disposition model with first-order absorption and elimination following subcutaneous and intravenous administration at 2.1-420 and 210-700 mg, respectively. There were no clinically relevant effects on tezepelumab pharmacokinetics from age (≥12 years), sex, race/ethnicity, renal or hepatic function, disease severity (inhaled corticosteroid dose level), concomitant asthma medication use, smoking history, or anti-drug antibodies. Body weight was the most influential covariate on tezepelumab exposure, but no meaningful differences in efficacy or safety were observed across body weight quartiles in patients with asthma who received tezepelumab 210 mg subcutaneously Q4W. There was no apparent relationship between tezepelumab exposure and efficacy at this dose regimen, suggesting that it is on the plateau of the exposure-response curve of tezepelumab. In conclusion, a fixed-dose regimen of tezepelumab 210 mg subcutaneously Q4W is appropriate for eligible adults and adolescents with severe, uncontrolled asthma.

3.
Clin Transl Sci ; 17(3): e13769, 2024 03.
Artigo em Inglês | MEDLINE | ID: mdl-38515348

RESUMO

Tislelizumab, an anti-programmed cell death protein 1 monoclonal antibody, has demonstrated improved survival benefits over standard of care for multiple cancer indications. We present the clinical rationale and data supporting tislelizumab dose recommendation in patients with advanced tumors. The phase I, first-in-human, dose-finding BGB-A317-001 study (data cutoff [DCO]: August 2017) examined the following tislelizumab dosing regimens: 0.5-10 mg/kg every 2 weeks (q2w), 2-5 mg/kg q2w or q3w, and 200 mg q3w. Similar objective response rates (ORRs) were reported in the 2 and 5 mg/kg q2w or q3w cohorts. Safety outcomes (grade ≥3 adverse events [AEs], AEs leading to dose modification/discontinuation, immune-mediated AEs, and infusion-related reactions) were generally comparable across the dosing range examined. These results, alongside the convenience of a fixed q3w dose, formed the basis of choosing 200 mg q3w as the recommended dosing regimen for further clinical use. Pooled exposure-response (E-R) analyses by logistic regression using data from study BGB-A317-001 (DCO: August 2020) and three additional phase I/II studies (DCOs: 2018-2020) showed no statistically significant correlation between tislelizumab pharmacokinetic exposure and ORR across multiple solid tumor types or classical Hodgkin's lymphoma, nor was exposure associated with any of the safety end points evaluated over the dose range tested. Hence, tislelizumab showed a relatively flat E-R relationship. Overall, the totality of data, including efficacy, safety, and E-R analyses, together with the relative convenience of a fixed q3w dose, provided clinical rationale for the recommended dosing regimen of tislelizumab 200 mg q3w for multiple cancer indications.


Assuntos
Efeitos Colaterais e Reações Adversas Relacionados a Medicamentos , Neoplasias Hematológicas , Neoplasias , Humanos , Anticorpos Monoclonais Humanizados/farmacocinética , Neoplasias/patologia
4.
Eur J Pharm Sci ; 195: 106713, 2024 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-38295963

RESUMO

PURPOSE: Omadacycline (PTK-0796) is a first-in-class aminomethylcycline for adult patients with community-acquired bacterial pneumonia (CABP) and acute bacterial skin and skin structure infections (ABSSSI) caused by susceptible pathogens. We investigated the pharmacokinetic (PK) and pharmacodynamic (PD) profile of omadacycline, considering the impact of covariates, particularly ethnicity, on PK and determined the PK/PD cutoff values for dosing regimens. METHODS: Utilizing nonlinear mixed-effects modeling, we pooled data from 11 clinical trials for PopPK analysis. The first-order conditional estimation with interaction (FOCEI) method in NONMEM facilitated model parameter estimation. Employing a stepwise model selection strategy, with forward addition (P < 0.01) and backward deletion (P < 0.001), we assessed the potential impacts of covariates on omadacycline PK, including baseline age, body weight, sex, race, body mass index, body surface area, baseline albumin, creatine clearance, and formulation. After validating the model through various methods, the final PopPK model underwent Monte Carlo simulations to generate the PK profile for the Chinese population. This enabled AUC calculation and assessment of the probability of target attainment (PTA) and the cumulative fraction of response (CFR) for various dosing regimens and bacterial strains. RESULTS: Omadacycline's PK can be adequately characterized by a three-compartment model. Body weight, sex, race, and drug formulation statistically influenced its PK. Asians and non-Asians exhibit similar exposure after intravenous infusion, but oral dosing results in much higher exposures than in non-Asians. Monte Carlo simulation indicates that IV-only or IV/PO sequential therapy regimens provide adequate attainment for all major pathogens causing ABSSSI and CABP. PK/PD cutoffs were generally above the MIC90 value of recent clinical isolates from China. CONCLUSIONS: In conclusion, the approved regimen for China achieved adequate target attainment for all pathogens typically associated with these infections. The higher oral exposure observed in Asians may enhance efficacy without affecting safety or tolerability.


Assuntos
Antibacterianos , Tetraciclinas , Adulto , Humanos , Antibacterianos/farmacologia , Tetraciclinas/farmacologia , Bactérias , Peso Corporal , Testes de Sensibilidade Microbiana , Método de Monte Carlo
5.
J Hazard Mater ; 465: 133141, 2024 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-38056262

RESUMO

The input of microplastics (MPs) and warming interfere with soil carbon (C) or nitrogen (N) cycles. Although the effects of warming and/or MPs on the cycles have been well studied, the biological coupling of microbial-driven cycles was neglected. Here, the synergistic changes of the cycles were investigated using batch incubation experiments. As results, the influences of MPs were not significant at 15, 20, and 25 °C, and yet, high temperature (i.e., 30 °C) reduced the respiration of high-concentration MPs-amended soil by 9.80%, and increased dissolved organic carbon (DOC) by 14.74%. In contrast, high temperature did not change the effect of MPs on N. The decrease of microbial biomass carbon (MBC) and the constant of microbial biomass nitrogen (MBN) indicated that microbial N utilization was enhanced, which might be attributed to the enrichments of adapted populations, such as Conexibacter, Acidothermus, and Acidibacter. These observations revealed that high temperature and MPs drove the differential response of soil C and N cycles. Additionally, the transcriptomic provided genomic evidence of the response. In summary, the high temperature was a prerequisite for the MPs-driven response, which underscored new ecological risks of MPs under global warming and emphasized the need for carbon emission reduction and better plastic product regulation.


Assuntos
Microplásticos , Plásticos , Solo , Carbono , Microbiologia do Solo , Nitrogênio/análise , Ciclo do Nitrogênio
6.
Nano Lett ; 23(8): 3540-3548, 2023 Apr 26.
Artigo em Inglês | MEDLINE | ID: mdl-37026801

RESUMO

Surface plasmon resonance-induced charge separation plays key roles in plasmon-related applications, especially in photocatalysis and photovoltaics. Plasmon coupling nanostructures exhibit extraordinary behaviors in hybrid states, phonon scattering, and ultrafast plasmon dephasing, but plasmon-induced charge separation in these materials remains unknown. Here, we design Schottky-free Au nanoparticle (NP)/NiO/Au nanoparticles-on-a-mirror plasmonic photocatalysts to support plasmon-induced interfacial hole transfer, evidenced by surface photovoltage microscopy at the single-particle level. In particular, we observe a nonlinear increase in charge density and photocatalytic performance with an increase in excitation intensity in plasmonic photocatalysts containing hot spots as a result of varying the geometry. Such charge separation increased the internal quantum efficiency by 14 times at 600 nm in catalytic reactions as compared to that of the Au NP/NiO without a coupling effect. These observations provide an improved understanding of charge transfer management and utilization by geometric engineering and interface electronic structure for plasmonic photocatalysis.

7.
CPT Pharmacometrics Syst Pharmacol ; 12(1): 95-109, 2023 01.
Artigo em Inglês | MEDLINE | ID: mdl-36330700

RESUMO

Tislelizumab, a humanized immunoglobulin G4 monoclonal antibody, is a programmed cell death protein 1 (PD-1) inhibitor designed to minimize Fc gamma receptor binding on macrophages to limit antibody-dependent phagocytosis, a potential mechanism of resistance to anti-PD-1 therapy. The pharmacokinetic (PK) profile of tislelizumab was analyzed with population PK modeling using 14,473 observed serum concentration data points from 2596 cancer patients who received intravenous (i.v.) tislelizumab at 0.5-10 mg/kg every 2 weeks or every 3 weeks (q3w), or a 200 mg i.v. flat dose q3w in 12 clinical studies. Tislelizumab exhibited linear PK across the dose range tested. Baseline body weight, albumin, tumor size, tumor type, and presence of antidrug antibodies were identified as significant covariates on central clearance, whereas baseline body weight, sex, and age significantly affected central volume of distribution. Sensitivity analysis showed that these covariates did not have clinically relevant effects on tislelizumab PK. Other covariates evaluated, including race (Asian vs. White), lactate dehydrogenase, estimated glomerular filtration rate, renal function categories, hepatic function measures and categories, Eastern Cooperative Oncology Group performance status, therapy (monotherapy vs. combination therapy), and line of therapy did not show a statistically significant impact on tislelizumab PK. These results support the use of tislelizumab 200 mg i.v. q3w without dose adjustment in a variety of patient subpopulations.


Assuntos
Anticorpos Monoclonais Humanizados , Neoplasias , Humanos , Anticorpos Monoclonais Humanizados/farmacocinética , Neoplasias/tratamento farmacológico , Neoplasias/patologia , Administração Intravenosa , Peso Corporal
8.
Chemosphere ; 312(Pt 1): 137145, 2023 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-36343739

RESUMO

The rapid recombination of photogenerated electrons and holes, low utilization of visible light and weak oxidation capacity significantly limit the photocatalytic activity for the degradation of organic pollutants. Doping is used as a conventional strategy for regulating the electronic structure of photocatalysts to obtain a wider light absorption, but also suffers from the problems of reduced charge mobility and oxidation capacity, which is not conducive to photocatalytic degradation of pollutants. To address this issue, a nitrogen self-doped hollow nanotubes g-C3N4 (N-PCN) was synthesized by synergistic self-doping and quantum confinement effects. The N-PCN exhibits excellent efficiency in photocatalytic degradation of TC compared to the pristine g-C3N4. The synthesized N-PCN has a more positive conduction band minimum and can generate more photogenerated electrons to reduce oxygen to superoxide radicals. In addition, experimental and theoretical evidence shows that N-self-doping not only suppresses the recombination of photogenerated charge carriers but also facilitates the adsorption of oxygen molecules. Consequently, more superoxide radicals and singlet oxygen are generated through oxygen activation process.


Assuntos
Poluentes Ambientais , Catálise , Nanotubos de Carbono/química , Nitrogênio , Oxigênio/química , Superóxidos
9.
ACS Appl Mater Interfaces ; 14(43): 48682-48693, 2022 Nov 02.
Artigo em Inglês | MEDLINE | ID: mdl-36265862

RESUMO

BiVO4 with an appropriate band structure is considered to be an ideal candidate for photoanodes. However, slow water oxidation kinetics and low charge separation efficiency seriously restrict its application. To address these issues, an NF/N/BVO photoanode with a hierarchical network structure was successfully constructed by direct-current magnetron sputtering of Ni followed by electrochemical deposition of nickel-iron layered double hydroxide (NiFe-LDH) on BiVO4. A photocurrent density of 4.50 mA/cm2 was obtained for NF/N/BVO, which was 2.4 times that for pristine BiVO4. The introduction of the Ni layer contributed to the following growth of NiFe-LDH nanosheets with larger size, which acted as active sites and speeded up water oxidation kinetics. Furthermore, surface photovoltage microscopy revealed that Ni and NiFe-LDH acted as the electron collector and hole reservoir, respectively. The co-existence of the two components constituted a highly efficient surface charge separation structure, which was one of the important issues for the excellent water oxidation activity.

10.
Biol Pharm Bull ; 45(9): 1347-1353, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-36047204

RESUMO

Abacavir (ABC)-induced hypersensitivity (AHS) is strongly associated with human leukocyte antigen (HLA)-B*57 : 01 expression. Previous studies have demonstrated the feasibility of applying the HLA-transgenic mouse model in this context. ABC-induced adverse reactions were observed in HLA-B*57 : 01 transgenic (B*57 : 01-Tg) mice. Moreover, regulating immune tolerance could result in severe AHS that mimics symptoms observed in the clinical setting, which were modeled in CD4+ T cell-depleted programmed death-1 receptor (PD-1) knockout B*57 : 01-Tg (B*57 : 01-Tg/PD-1-/-) mice. Here, we aimed to examine whether thymus and activation-regulated chemokine (TARC)/CCL17 level can be used as a biomarker for AHS. Serum TARC levels increased in HLA-B*57 : 01-transgenic mice following oral administration of ABC; this increase was associated with the severity of skin toxicity. In ABC-fed CD4+ T cell-depleted B*57 : 01-Tg/PD-1-/- mice, TARC was detected in the epidermal keratinocytes of the ear. Skin toxicity was characterized by the infiltration of CD8+ T cells partially expressing C-C chemokine receptor type 4, which is the primary receptor for TARC. In vivo TARC neutralization effectively alleviated the symptoms of ear skin redness and blood vessel dilatation. Moreover, TARC neutralization suppressed the infiltration of CD8+ T cells to the ear skin but did not affect the ABC-induced adaptive immune response. Therefore, TARC was involved in ABC-induced skin toxicity and contributed to the recruitment of CD8+ T cells to skin. This evidence suggests that serum TARC level may be a functional biomarker for AHS.


Assuntos
Linfócitos T CD8-Positivos , Quimiocina CCL17 , Dermatite Atópica , Animais , Linfócitos T CD8-Positivos/imunologia , Quimiocina CCL17/genética , Quimiocinas , Ciclopropanos/efeitos adversos , Didesoxiadenosina/efeitos adversos , Didesoxiadenosina/análogos & derivados , Antígenos HLA-B/genética , Humanos , Camundongos , Camundongos Transgênicos , Receptor de Morte Celular Programada 1
11.
Immunol Lett ; 249: 5-11, 2022 09.
Artigo em Inglês | MEDLINE | ID: mdl-35963284

RESUMO

Flucloxacillin (FLX) induces adverse liver reactions, which has been reported to be related to human leukocyte antigen (HLA)-B*57:01. In a previous study, abacavir-induced hypersensitivity was induced in HLA-B*57:01-transgenic mice (B*57:01-Tg), originally constructed by our group (Susukida et al., 2021). In this study, B*57:01-Tg mice were used to reproduce FLX-induced liver injury. However, treatment of B*57:01-Tg mice with FLX alone did not increase serum ALT levels. Immune-deficient B*57:01-Tg/PD-1-/-mice were produced by mating B*57:01-Tg with PD-1-/- mice. The immune response of B*57:01-Tg/PD-1-/- mice was further modulated by co-administration of CpG-oligodeoxynucleotides and anti-CD4 mAb. Nevertheless, immune regulation in B*57:01-Tg mice did not contribute to the onset of FLX-induced liver injury or immune activation. Moreover, we generated an FLX-human serum albumin (HSA) conjugate and showed that FLX covalently bound to HSA in a time-dependent manner. The FLX-HSA conjugate was administered to the B*57:01-Tg mice. The immune response was investigated using flow cytometry, revealing the phenotype of CD44highCD62Llow in CD8+ T cells (TEM cells). Administration of the FLX-HSA conjugate resulted in an HLA-B*57:01 restricted immune response as shown by the stimulation of TEM cells in the draining lymph nodes. In conclusion, administration of FLX alone to B*57:01-Tg mice did not induce liver injury or immune activation. Immune system sensitivity does not play a decisive role in this process. The conjugation of FLX and HSA results in specific TEM cell stimulation, which suggests that HLA-B*57:01 drives a stronger interaction with CD8+ T cells. These results suggest that patients carrying HLA-B*57:01 could be more susceptible to a conjugate of FLX and albumin and drive CD8+ T cell activation, which may be a vital risk factor for FLX-induced liver injury. In addition, the application of the FLX-HSA adduct may be an effective method for the construction of FLX-induced idiosyncratic liver injury in mice.


Assuntos
Doença Hepática Crônica Induzida por Substâncias e Drogas , Floxacilina , Animais , Linfócitos T CD8-Positivos , Floxacilina/farmacologia , Antígenos HLA-B/genética , Humanos , Ativação Linfocitária , Camundongos , Camundongos Transgênicos , Oligodesoxirribonucleotídeos/farmacologia , Receptor de Morte Celular Programada 1 , Albumina Sérica Humana/farmacologia
12.
Front Med (Lausanne) ; 9: 855335, 2022.
Artigo em Inglês | MEDLINE | ID: mdl-35492366

RESUMO

Idiopathic myointimal hyperplasia of the mesenteric veins (IMHMV) is a rare and poorly understood disease. It is characterized by non-thrombotic and non-inflammatory occlusion of the mesenteric veins secondary to intimal smooth muscle hyperplasia. The etiology of IMHMV is unknown, and its clinical presentations include abdominal pain, bloody diarrhea, and weight loss. IMHMV is commonly mistaken for inflammatory bowel disease because of the similarity in symptoms and endoscopic findings. Herein, we report the case of a 64-year-old man with IMHMV and present an overview of all reported cases of IMHMV. In this review, we analyzed 70 cases to summarize the etiology, clinical manifestations, and diagnosis of IMHMV and hope to raise clinicians' awareness of this entity.

13.
Angew Chem Int Ed Engl ; 61(28): e202204108, 2022 Jul 11.
Artigo em Inglês | MEDLINE | ID: mdl-35522460

RESUMO

Metal-organic frameworks (MOFs) have been intensively studied as a class of semiconductor-like materials in photocatalysis. However, band bending, which plays a crucial role in semiconductor photocatalysis, has not yet been demonstrated in MOF photocatalysts. Herein, a representative MOF, MIL-125-NH2 , is integrated with the metal oxides (MoO3 and V2 O5 ) that feature appropriate work functions and energy levels to afford the corresponding MOF composites. Surface photovoltage results demonstrate band bending in the MOF composites, which gives rise to the built-in electric field of MIL-125-NH2 , boosting the charge separation. As a result, the MOF composites present 56 and 42 times higher activities, respectively, compared to the pristine MOF for photocatalytic H2 production. Upon depositing Pt onto the MOF, ∼6 times higher activity is achieved. This work illustrates band bending of MOFs for the first time, supporting their semiconductor-like nature, which would greatly promote MOF photocatalysis.

14.
Angew Chem Int Ed Engl ; 61(30): e202204272, 2022 Jul 25.
Artigo em Inglês | MEDLINE | ID: mdl-35535639

RESUMO

Plasmon-induced chemical reaction is an emerging field but its development faces huge challenges because of low quantum efficiency. Herein, we report that the solar energy conversion efficiency of Au/TiO2 in plasmon-induced water oxidation is greatly enhanced by intercalating Li+ into TiO2 . An incident photon-to-current efficiency as high as 2.0 %@520 nm is achieved by Au/Li0.2 TiO2 in photoelectrocatalytic water oxidation, realizing a 33-fold enhancement in photocurrent density compared with Au/TiO2 . The superior photoelectrocatalytic performance is mainly ascribed to the enhanced electric conductivity and higher catalytic activity of Li0.2 TiO2 . Furthermore, the ultrafast transient absorption spectroscopy suggests that lithium intercalation into TiO2 could change the dynamics of hot electron relaxation in Au nanoparticles. This work demonstrates that intercalation of alkaline ions into semiconductors can promote the charge separation efficiency of the plasmonic effect of Au/TiO2 .

18.
Adv Mater ; 34(3): e2106662, 2022 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-34695250

RESUMO

Inspired by green plants, artificial photosynthesis has become one of the most attractive approaches toward carbon dioxide (CO2 ) valorization. Semiconductor quantum dots (QDs) or dot-in-rod (DIR) nano-heterostructures have gained substantial research interest in multielectron photoredox reactions. However, fast electron-hole recombination or sluggish hole transfer and utilization remains unsatisfactory for their potential applications. Here, the first application of a well-designed ZnSe/CdS dot-on-rods (DORs) nano-heterostructure for efficient and selective CO2 photoreduction with H2 O as an electron donor is presented. In-depth spectroscopic studies reveal that surface-anchored ZnSe QDs not only assist ultrafast (≈2 ps) electron and hole separation, but also promote interfacial hole transfer participating in oxidative half-reactions. Surface photovoltage (SPV) spectroscopy provides a direct image of spatially separated electrons in CdS and holes in ZnSe. Therefore, ZnSe/CdS DORs photocatalyze CO2 to CO with a rate of ≈11.3 µmol g-1 h-1 and ≥85% selectivity, much higher than that of ZnSe/CdS DIRs or pristine CdS nanorods under identical conditions. Obviously, favored energy-level alignment and unique morphology balance the utilization of electrons and holes in this nano-heterostructure, thus enhancing the performance of artificial photosynthetic solar-to-chemical conversion.

19.
J Phys Chem Lett ; 12(44): 10829-10836, 2021 Nov 11.
Artigo em Inglês | MEDLINE | ID: mdl-34726399

RESUMO

Understanding the role of surface charges in the catalytic reaction is of great importance to fundamental science in photoelectrochemistry (PEC). However, spatial heterogeneities of charge transfer sites and catalytic sites at the electrode/electrolyte interface obscures the surface reaction process. Herein, we quantified the relationship between the local catalytic current of the hydrogen evolution reaction (HER) and the surface charge density using operando spatially resolved photovoltage microscopy on the Pt/Ti array on the p-Si photoelectrode. We found that the Pt/Ti islands on the p-Si surface worked as the main charge collect areas but as the sole catalytic sites to drive the PEC hydrogen evolution. Based on the achievements of identifying the local photocurrent and photovoltage on a single Pt/Ti island, we found that the local HER current can be linearly regulated by the charge density at reactive sites by concurrently adjusting the bias potential and the spacings of the Pt/Ti islands. These results emphasize the significant impact of the surface charge density on the catalytic activity in photoelectrochemistry.

20.
Nano Lett ; 21(20): 8901-8909, 2021 Oct 27.
Artigo em Inglês | MEDLINE | ID: mdl-34647747

RESUMO

The involvement between electron transfer (ET) and catalytic reaction at the electrocatalyst surface makes the electrochemical process challenging to understand and control. Even ET process, a primary step, is still ambiguous because it is unclear how the ET process is related to the nanostructured electrocatalyst. Herein, locally enhanced ET current dominated by mass transport effect at corner and edge sites bounded by {111} facets on single Au triangular nanoplates was clearly imaged. After decoupling mass transport effect, the ET rate constant of corner sites was measured to be about 2-fold that of basal {111} plane. Further, we demonstrated that spatial heterogeneity of local inner potential differences of Au nanoplates/solution interfaces plays a key role in the ET process, supported by the linear correlation between the logarithm of rate constants and the potential differences of different sites. These results provide direct images for heterogeneous ET, which helps to understand and control the nanoscopic electrochemical process and electrode design.

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