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1.
J Chem Theory Comput ; 20(10): 4254-4264, 2024 May 28.
Article in English | MEDLINE | ID: mdl-38727197

ABSTRACT

We propose an X-ray Raman pump-X-ray diffraction probe scheme to follow solvation dynamics upon charge migration in a solute molecule. The X-ray Raman pump selectively prepares a valence electronic wavepacket in the solute, while the probe provides information about the entire molecular ensemble. A combination of molecular dynamics and ab initio quantum chemistry simulations is applied to a Zn-Ni porphyrin dimer in water. Using time-resolved X-ray diffraction and pair distribution functions, we extracted solvation shell dynamics.

2.
Eur Heart J ; 2024 May 15.
Article in English | MEDLINE | ID: mdl-38747976

ABSTRACT

BACKGROUND AND AIMS: Brugada syndrome (BrS) is an inherited arrhythmia with a higher disease prevalence and more lethal arrhythmic events in Asians than in Europeans. Genome-wide association studies (GWAS) have revealed its polygenic architecture mainly in European populations. The aim of this study was to identify novel BrS-associated loci and to compare allelic effects across ancestries. METHODS: A GWAS was conducted in Japanese participants, involving 940 cases and 1634 controls, followed by a cross-ancestry meta-analysis of Japanese and European GWAS (total of 3760 cases and 11 635 controls). The novel loci were characterized by fine-mapping, gene expression, and splicing quantitative trait associations in the human heart. RESULTS: The Japanese-specific GWAS identified one novel locus near ZSCAN20 (P = 1.0 × 10-8), and the cross-ancestry meta-analysis identified 17 association signals, including six novel loci. The effect directions of the 17 lead variants were consistent (94.1%; P for sign test = 2.7 × 10-4), and their allelic effects were highly correlated across ancestries (Pearson's R = .91; P = 2.9 × 10-7). The genetic risk score derived from the BrS GWAS of European ancestry was significantly associated with the risk of BrS in the Japanese population [odds ratio 2.12 (95% confidence interval 1.94-2.31); P = 1.2 × 10-61], suggesting a shared genetic architecture across ancestries. Functional characterization revealed that a lead variant in CAMK2D promotes alternative splicing, resulting in an isoform switch of calmodulin kinase II-δ, favouring a pro-inflammatory/pro-death pathway. CONCLUSIONS: This study demonstrates novel susceptibility loci implicating potentially novel pathogenesis underlying BrS. Despite differences in clinical expressivity and epidemiology, the polygenic architecture of BrS was substantially shared across ancestries.

3.
Am J Hypertens ; 2024 May 22.
Article in English | MEDLINE | ID: mdl-38776410

ABSTRACT

BACKGROUND/AIMS: In primary aldosteronism (PA), aldosterone could affect glomerular hemodynamics by elevating renal vascular resistance and glomerular capillary pressure. However, the relationship between plasma aldosterone concentrations (PAC) and glomerular hemodynamics including efferent arteriolar resistance (Re), afferent arteriolar resistance (Ra) in humans is still unclear. The aim of this study was to investigate the relationships of PAC with intraglomerular hemodynamic parameters in patients with PA. METHODS: An observational study of glomerular hemodynamics was performed using simultaneous measurements of plasma clearance of para-aminohippurate and inulin (Cin; glomerular filtration rate (GFR)) in 17 patients with PA. Kidney function was evaluated by Cin, estimated GFR based on serum creatine (eGFRcre) and serum cystatin C (eGFRcys) and creatine clearance (Ccr). Intraglomerular hemodynamic parameters, including Re, Ra, and intraglomerular hydrostatic pressure (Pglo) were calculated using Gomez's formulae. RESULTS: In the 17 PA cases, PAC was significantly correlated with Cin (rho=0.752, p=0.001) and eGFRcys (rho=0.567, p=0.018), but was not correlated witheGFRcreand Ccr. PAC was also significantly correlated with Pglo, Re, and urinary protein/day (rho=0.775, p=0.0004, rho=0.625, p=0.009, and rho=0.625, p=0.007, respectively). Multivariable regression analysis showed that PAC was significantly associated with Cin and Re. In comparing aldosterone producing adenoma (APA) and non-APA cases, Cin was significantly elevated in APA (p=0.037), whereas eGFRcre, eGFRcys, and Ccr were not. Re tended to be higher in APA (p=0.064). CONCLUSIONS: These results suggest high aldosterone cause glomerular hyperfiltration by constricting Re. Cin, but not eGFRcre and Ccr, may be useful for evaluating kidney function in PA.

4.
Adv Mater ; : e2311470, 2024 May 17.
Article in English | MEDLINE | ID: mdl-38760007

ABSTRACT

Layers of nanometer thick polydimethylsiloxane (PDMS) are applied as hydrophobic coatings because of their environmentally friendly and chemically inert properties. In applications such as heat exchangers or fog harvesting, low water drop friction on surfaces is required. While the onset of motion (static friction) has been studied, the knowledge of dynamic friction needs to be improved. To minimize drop friction, it is essential to understand which processes lead to energy dissipation and cause dynamic friction? Here, the dynamic friction of drops on PDMS brushes of different thicknesses is measured, covering the whole available velocity regime. The brush thickness L turns out to be a predictor for drop friction. 4-5 nm thick PDMS brush shows the lowest dynamic friction. A certain minimal thickness is necessary to form homogeneous surfaces and reduce the attractive van der Waals interaction between water and the substrate. The increase in dynamic friction above L = 5 nm is also attributed to the increasing viscoelastic dissipation of the capillary ridge formed at the contact line. The height of the ridge is related to the brush thickness. Fluorescence correlation spectroscopy and atomic force measurements support this interpretation. Sum-frequency generation further indicates a maximum order at the PDMS-water interface at intermediate thickness.

5.
Angew Chem Int Ed Engl ; 63(20): e202319503, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38478726

ABSTRACT

Graphene, a transparent two-dimensional conductive material, has brought extensive new perspectives and prospects to various aqueous technological systems, such as desalination membranes, chemical sensors, energy storage, and energy conversion devices. Yet, the molecular-level details of graphene in contact with aqueous electrolytes, such as water orientation and hydrogen bond structure, remain elusive or controversial. Here, we employ surface-specific heterodyne-detected sum-frequency generation (HD-SFG) vibrational spectroscopy to re-examine the water molecular structure at a freely suspended graphene/water interface. We compare the response from the air/graphene/water system to that from the air/water interface. Our results indicate that the χ y y z 2 ${{\chi }_{yyz}^{\left(2\right)}}$ spectrum recorded from the air/graphene/water system arises from the topmost 1-2 water layers in contact with the graphene, with the graphene itself not generating a significant SFG response. Compared to the air/water interface response, the presence of monolayer graphene weakly affects the interfacial water. Graphene weakly affects the dangling O-H group, lowering its frequency through its interaction with the graphene sheet, and has a very small effect on the hydrogen-bonded O-H group. Molecular dynamics simulations confirm our experimental observation. Our work provides molecular insight into the interfacial structure at a suspended graphene/water interface, relevant to various technological applications of graphene.

6.
Cancer Sci ; 115(6): 1763-1777, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38527308

ABSTRACT

Overcoming resistance to immune checkpoint inhibitors is an important issue in patients with non-small-cell lung cancer (NSCLC). Transcriptome analysis shows that adenocarcinoma can be divided into three molecular subtypes: terminal respiratory unit (TRU), proximal proliferative (PP), and proximal inflammatory (PI), and squamous cell carcinoma (LUSQ) into four. However, the immunological characteristics of these subtypes are not fully understood. In this study, we investigated the immune landscape of NSCLC tissues in molecular subtypes using a multi-omics dataset, including tumor-infiltrating leukocytes (TILs) analyzed using flow cytometry, RNA sequences, whole exome sequences, metabolomic analysis, and clinicopathologic findings. In the PI subtype, the number of TILs increased and the immune response in the tumor microenvironment (TME) was activated, as indicated by high levels of tertiary lymphoid structures, and high cytotoxic marker levels. Patient prognosis was worse in the PP subtype than in other adenocarcinoma subtypes. Glucose transporter 1 (GLUT1) expression levels were upregulated and lactate accumulated in the TME of the PP subtype. This could lead to the formation of an immunosuppressive TME, including the inactivation of antigen-presenting cells. The TRU subtype had low biological malignancy and "cold" tumor-immune phenotypes. Squamous cell carcinoma (LUSQ) did not show distinct immunological characteristics in its respective subtypes. Elucidation of the immune characteristics of molecular subtypes could lead to the development of personalized immune therapy for lung cancer. Immune checkpoint inhibitors could be an effective treatment for the PI subtype. Glycolysis is a potential target for converting an immunosuppressive TME into an antitumorigenic TME in the PP subtype.


Subject(s)
Adenocarcinoma of Lung , Glucose Transporter Type 1 , Lung Neoplasms , Lymphocytes, Tumor-Infiltrating , Tumor Microenvironment , Humans , Tumor Microenvironment/immunology , Lung Neoplasms/immunology , Lung Neoplasms/genetics , Lung Neoplasms/pathology , Adenocarcinoma of Lung/immunology , Adenocarcinoma of Lung/pathology , Adenocarcinoma of Lung/genetics , Lymphocytes, Tumor-Infiltrating/immunology , Lymphocytes, Tumor-Infiltrating/metabolism , Glucose Transporter Type 1/genetics , Glucose Transporter Type 1/metabolism , Carcinoma, Squamous Cell/immunology , Carcinoma, Squamous Cell/genetics , Carcinoma, Squamous Cell/pathology , Prognosis , Carcinoma, Non-Small-Cell Lung/immunology , Carcinoma, Non-Small-Cell Lung/genetics , Carcinoma, Non-Small-Cell Lung/pathology , Male , Female , Aged , Gene Expression Regulation, Neoplastic , Middle Aged , Gene Expression Profiling
7.
J Chem Phys ; 160(11)2024 Mar 21.
Article in English | MEDLINE | ID: mdl-38506293

ABSTRACT

Unsaturated lipids with C=C groups in their alkyl chains are widely present in the cell membrane and food. The C=C groups alter the lipid packing density, membrane stability, and persistence against lipid oxidation. Yet, molecular-level insights into the structure of the unsaturated lipids remain scarce. Here, we probe the molecular structure and organization of monolayers of unsaturated lipids on the water surface using heterodyne-detected sum-frequency generation (HD-SFG) spectroscopy. We vary the location of the C=C in the alkyl chain and find that at high lipid density, the location of the C=C group affects neither the interfacial water organization nor the tail of the alkyl chain. Based on this observation, we use the C=C stretch HD-SFG response to depth-profile the alkyl chain conformation of the unsaturated lipid. We find that the first 1/3 of carbon atoms from the headgroup are relatively rigid, oriented perpendicular to the surface. In contrast, the remaining carbon atoms can be approximated as free rotators, introducing the disordering of the alkyl chains.

8.
Cureus ; 16(3): e56188, 2024 Mar.
Article in English | MEDLINE | ID: mdl-38487650

ABSTRACT

Background This study aimed to evaluate postoperative changes in ocular biometry following initial PreserFlo MicroShunt implantation and trabeculectomy. Methodology This prospective, observational study analyzed 27 cases of PreserFlo MicroShunt implantation and 29 cases of trabeculectomy performed by a single surgeon. Visual acuity, intraocular pressure, corneal curvature, central corneal thickness, anterior chamber depth, and axial length were assessed at baseline and postoperatively at one day, one week, two weeks, one month, two months, three months, and six months. Patients requiring additional surgery and those with missing data were excluded. Consecutive data were compared with the baseline values using multiple comparisons. Results In both groups, intraocular pressure was significantly decreased from baseline at all postoperative time points (all p < 0.01). Visual acuity decreased in both groups at one day and one week postoperatively. Corneal curvature remained unchanged in both groups throughout the six-month follow-up. Central corneal thickness increased at one day and one week postoperatively in the PreserFlo group, but not in the trabeculectomy group. Anterior chamber depth exhibited a significant decrease at one week postoperatively in both groups. Axial length significantly decreased postoperatively until three months in the PreserFlo group and at all postoperative time points in the trabeculectomy group. Conclusions Ocular biometry following PreserFlo and trabeculectomy had a similar tendency postoperatively.

9.
Environ Sci Technol ; 58(8): 3830-3837, 2024 Feb 27.
Article in English | MEDLINE | ID: mdl-38353041

ABSTRACT

Ions containing iodine atoms at the vapor-aqueous solution interfaces critically affect aerosol growth and atmospheric chemistry due to their complex chemical nature and multivalency. While the surface propensity of iodide ions has been intensely discussed in the context of the Hofmeister series, the stability of various ions containing iodine atoms at the vapor-water interface has been debated. Here, we combine surface-specific sum-frequency generation (SFG) vibrational spectroscopy with ab initio molecular dynamics simulations to examine the extent to which iodide ions cover the aqueous surface. The SFG probe of the free O-D stretch mode of heavy water indicates that the free O-D group density decreases drastically at the interface when the bulk NaI concentration exceeds ∼2 M. The decrease in the free O-D group density is attributed to the spontaneous appearance of triiodide that covers the topmost interface rather than to the surface adsorption of iodide. This finding demonstrates that iodide is not surface-active, yet the highly surface-active triiodide is generated spontaneously at the water-air interface, even under dark and oxygen-free conditions. Our study provides an important first step toward clarifying iodine chemistry and pathways for aerosol formation.


Subject(s)
Iodides , Iodine , Water/chemistry , Ions/chemistry , Gases , Aerosols
10.
Proc Natl Acad Sci U S A ; 121(6): e2314347121, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-38300862

ABSTRACT

Memristive devices, electrical elements whose resistance depends on the history of applied electrical signals, are leading candidates for future data storage and neuromorphic computing. Memristive devices typically rely on solid-state technology, while aqueous memristive devices are crucial for biology-related applications such as next-generation brain-machine interfaces. Here, we report a simple graphene-based aqueous memristive device with long-term and tunable memory regulated by reversible voltage-induced interfacial acid-base equilibria enabled by selective proton permeation through the graphene. Surface-specific vibrational spectroscopy verifies that the memory of the graphene resistivity arises from the hysteretic proton permeation through the graphene, apparent from the reorganization of interfacial water at the graphene/water interface. The proton permeation alters the surface charge density on the CaF2 substrate of the graphene, affecting graphene's electron mobility, and giving rise to synapse-like resistivity dynamics. The results pave the way for developing experimentally straightforward and conceptually simple aqueous electrolyte-based neuromorphic iontronics using two-dimensional (2D) materials.

11.
Nat Chem ; 16(4): 644-650, 2024 Apr.
Article in English | MEDLINE | ID: mdl-38225269

ABSTRACT

The distribution of ions at the air/water interface plays a decisive role in many natural processes. Several studies have reported that larger ions tend to be surface-active, implying ions are located on top of the water surface, thereby inducing electric fields that determine the interfacial water structure. Here we challenge this view by combining surface-specific heterodyne-detected vibrational sum-frequency generation with neural network-assisted ab initio molecular dynamics simulations. Our results show that ions in typical electrolyte solutions are, in fact, located in a subsurface region, leading to a stratification of such interfaces into two distinctive water layers. The outermost surface is ion-depleted, and the subsurface layer is ion-enriched. This surface stratification is a key element in explaining the ion-induced water reorganization at the outermost air/water interface.

14.
Faraday Discuss ; 249(0): 303-316, 2024 Feb 06.
Article in English | MEDLINE | ID: mdl-37772472

ABSTRACT

Graphene, a transparent two-dimensional (2D) conductive electrode, has brought extensive new perspectives and prospects to electrochemical systems, such as chemical sensors, energy storage, and energy conversion devices. In many of these applications, graphene, supported on a substrate, is in contact with an aqueous solution. An increasing number of studies indicate that the substrate, rather than graphene, determines the organization of water in contact with graphene, i.e., the electric double layer (EDL) structure near the electrified graphene, and the wetting behavior of the graphene: the graphene sheet is transparent in terms of its supporting substrate. By applying surface-specific heterodyne-detected sum-frequency generation (HD-SFG) spectroscopy to the silicon dioxide (SiO2)-supported graphene electrode/aqueous electrolyte interface and comparing the data with those for the calcium fluoride (CaF2)-supported graphene [Y. Wang et al., Angew. Chem., Int. Ed., 2023, 62, e202216604], we discuss the impact of the different substrates on the charging of both the graphene and the substrate upon applying potentials. The SiO2-supported graphene shows pseudocapacitive behavior, consistent with the CaF2-supported graphene case, although the surface charges on SiO2 and CaF2 differ substantially. The SiO2 surface is already negatively charged at +0.57 V (vs. Pd/H2), and the negative surface charge is doubled when negative potentials are applied, in contrast with the CaF2 case, where the positive charge is reduced when negative potentials are applied. Interestingly, the charging of the graphene sheet is almost identical between the negatively charged SiO2 surface and positively charged CaF2 surface, demonstrating that the graphene charging is decoupled from the charging of the substrates.

15.
J Pharm Health Care Sci ; 9(1): 43, 2023 Dec 01.
Article in English | MEDLINE | ID: mdl-38037095

ABSTRACT

BACKGROUND: Several methods have been reported for detecting resistance genes or phenotypic testing on the day of positive blood culture in Escherichia coli or Klebsiella pneumoniae bacteremia. However, some facilities have not introduced these methods because of costs or other reasons. Toyota Kosei Hospital introduced cefpodoxime (CPDX) rapid screening on May 7, 2018, to enable early detection of third-generation cephalosporin resistance. In this study, we aimed to evaluate the effects of intervention with an Antimicrobial Stewardship Team using CPDX rapid screening. METHODS: Cefotaxime (CTX)-resistant E. coli or K. pneumoniae bacteremia cases were selected retrospectively and divided into two groups: the pre-CPDX screening (June 1, 2015, to May 6, 2018) and CPDX screening groups (July 7, 2018, to August 31, 2021). The primary outcome was the proportion of cases in which modifications were made to the administration of susceptible antimicrobial agents within 24 h of blood culture-positive reports. RESULTS: Overall, 63 patients in the pre-CPDX screening group and 84 patients in the CPDX screening group were eligible for analysis. The proportion of patients who modified to susceptible antimicrobial agents within 24 h of blood culture-positive reports was significantly increased in the CPDX screening group compared to that in the pre-CPDX screening group (6.3% vs. 22.6%, p = 0.010). CONCLUSION: The results demonstrated that in CTX-resistant E. coli or K. pneumoniae bacteremia, CPDX rapid screening increased the proportion of early initiation of appropriate antimicrobial agents.

16.
Nat Commun ; 14(1): 8313, 2023 Dec 14.
Article in English | MEDLINE | ID: mdl-38097633

ABSTRACT

Controlling site-selectivity and reactivity in chemical reactions continues to be a key challenge in modern synthetic chemistry. Here, we demonstrate the discovery of site-selective chemical reactions on the water surface via a sequential assembly approach. A negatively charged surfactant monolayer on the water surface guides the electrostatically driven, epitaxial, and aligned assembly of reagent amino-substituted porphyrin molecules, resulting in a well-defined J-aggregated structure. This constrained geometry of the porphyrin molecules prompts the subsequent directional alignment of the perylenetetracarboxylic dianhydride reagent, enabling the selective formation of a one-sided imide bond between porphyrin and reagent. Surface-specific in-situ spectroscopies reveal the underlying mechanism of the dynamic interface that promotes multilayer growth of the site-selective imide product. The site-selective reaction on the water surface is further demonstrated by three reversible and irreversible chemical reactions, such as imide-, imine-, and 1, 3-diazole (imidazole)- bonds involving porphyrin molecules. This unique sequential assembly approach enables site-selective chemical reactions that can bring on-water surface synthesis to the forefront of modern organic chemistry.

17.
Cureus ; 15(10): e46441, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37927709

ABSTRACT

Secondary epiretinal membranes (ERMs) can develop from various causes, including those associated with glaucoma treatments such as trabeculectomy (TLE) and EX-PRESS (EXP) insertion surgery. This study aimed to investigate the occurrence of new ERMs and changes in preexisting ERMs following TLE or EXP insertion. Between April 2018 and March 2019, 102 and 74 eyes that underwent primary and standalone TLE and EXP insertion, respectively, were evaluated. Of these, 48 eyes were included in the TLE group and 32 eyes were included in the EXP group. Optical coherence tomography (OCT) was used to assess preoperative and postoperative ERMs. In the TLE group, postoperative ERMs were observed in one (case 1) (3%) out of 34 eyes without preexisting ERMs and in one (case 2) (7%) out of 14 eyes with preexisting ERMs, showing an increase in ERM stage. In the EXP group, postoperative ERMs were observed in one (case 3) (5%) out of 22 eyes without preexisting ERMs and in one (case 4) (10%) out of 10 eyes with preexisting ERMs, showing a decrease in the ERM stage. Case 1 was a 58-year-old man with primary open-angle glaucoma (POAG) in the left eye who underwent TLE. Although no preoperative ERMs were observed, postoperative ERM was noted at the three-month follow-up. Case 2 was a 49-year-old man with POAG in the right eye who underwent TLE. Although ERM was observed preoperatively, ERM progressed at six months postoperatively. Case 3 was a 59-year-old woman with POAG in the right eye who underwent EXP insertion. No preoperative ERMs were observed, but an ERM was noted at the 15-month follow-up. Case 4 was a 72-year-old woman with steroid-induced glaucoma in the right eye who underwent EXP insertion surgery. A preoperative ERM was present, and the foveal pit was absent; however, the foveal pit was observed at the 12-month follow-up. Despite the low incidence of ERMs, filtration surgery may be associated with ERM development and the progression or regression of preexisting ERMs.

18.
Int J Cardiol Heart Vasc ; 48: 101264, 2023 Oct.
Article in English | MEDLINE | ID: mdl-37680549

ABSTRACT

Background: Xanthine oxidoreductase (XOR) inhibitor administration, known to reduce uric acid and reactive oxygen species (ROS) production, also improves vascular endothelial function (VEF). This cross-sectional study examined our hypothesis that XOR contributes to impaired VEF through ROS but not uric acid production. Methods: In 395 subjects (196 males, 199 females) without urate-lowering agent administration who underwent a health examination, plasma XOR activity was determined using our highly sensitive assay based on [13C2,15N2] xanthine and liquid chromatography/triple quadrupole mass spectrometry. For VEF evaluation, flow-mediated dilatation (FMD) in the brachial artery was determined by ultrasound, with physical and laboratory measurements also obtained. Results: The median values for plasma XOR activity, serum uric acid, and FMD were 26.6 pmol/h/mL, 5.4 mg/dL, and 6.2%, respectively. Simple regression analysis showed weak correlations of both log plasma XOR activity and serum uric acid level with FMD (r = -0.213, p < 0.001 and r = -0.139, p = 0.006, respectively). However, multivariable linear regression analyses revealed that log plasma XOR activity but not serum uric acid level remained associated with FMD (ß = -0.116, p = 0.037 and ß = 0.041, p = 0.549, respectively) after adjustments for various clinical parameters, with no remarkable inconsistencies for the association observed in subgroups divided based on sex or uric acid level. Finally, a series of mediation analyses showed that serum uric acid level did not meet the criteria for mediator of the association of plasma XOR activity with FMD (p = 0.538). Conclusions: These findings suggest the possibility that XOR contributes to the pathophysiology of impaired VEF through ROS but not uric acid production.

19.
J Phys Chem Lett ; 14(36): 8175-8182, 2023 Sep 14.
Article in English | MEDLINE | ID: mdl-37671886

ABSTRACT

Our current understanding of the structure and dynamics of aqueous interfaces at the molecular level has grown substantially due to the continuous development of surface-specific spectroscopies, such as vibrational sum-frequency generation (VSFG). As in other vibrational spectroscopies, we must turn to atomistic simulations to extract all of the information encoded in the VSFG spectra. The high computational cost associated with existing methods means that they have limitations in representing systems with complex electronic structure or in achieving statistical convergence. In this work, we combine high-dimensional neural network interatomic potentials and symmetry-adapted Gaussian process regression to overcome these constraints. We show that it is possible to model VSFG signals with fully ab initio accuracy using machine learning and illustrate the versatility of our approach on the water/air interface. Our strategy allows us to identify the main sources of theoretical inaccuracy and establish a clear pathway toward the modeling of surface-sensitive spectroscopy of complex interfaces.

20.
Adv Sci (Weinh) ; 10(31): e2304082, 2023 Nov.
Article in English | MEDLINE | ID: mdl-37688335

ABSTRACT

Proton exchange membranes with high proton conductivity and low crossover of fuel molecules are required to realize advanced fuel-cell technology. The selective transportation of protons, which occurs by blocking the transportation of fuel molecules across a proton exchange membrane, is crucial to suppress crossover while maintaining a high proton conductivity. In this study, a simple yet powerful method is proposed for optimizing the crossover-conductivity relationship by pasting sulfanilic-functionalized holey graphenes onto a Nafion membrane. The results show that the sulfanilic-functionalized holey graphenes supported by the membrane suppresses the crossover by 89% in methanol and 80% in formate compared with that in the self-assembled Nafion membrane; an ≈60% reduction is observed in the proton conductivity. This method exhibits the potential for application in advanced fuel cells that use methanol and formic acid as chemical fuels to achieve high energy efficiency.

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