The Journal of Physical Chemistry B最新文献

{"title":"Mechanistic Insights into Lipooligourea-Lipid Membrane Interactions.","authors":"Kinga Burdach, Zuzanna Reterska, Arkadiusz Grempka, Damian Dziubak, Joanna Juhaniewicz-Dębińska, Paulina Bachurska-Szpala, Karolina Pulka-Ziach, Sławomir Sęk","doi":"10.1021/acs.jpcb.5c02112","DOIUrl":"10.1021/acs.jpcb.5c02112","url":null,"abstract":"<p><p>Understanding how synthetic peptidomimetics interact with bacterial membranes is key to developing next-generation antimicrobials. In this study, we investigate the membrane-disruptive behavior of C10-OU4, a cationic lipooligourea foldamer that mimics the amphiphilic architecture of antimicrobial lipopeptides. Using a multitechnique approach─Langmuir monolayer analysis, quartz crystal microbalance with dissipation monitoring (QCM-D), and attenuated total reflection-Fourier transform infrared spectroscopy (ATR-FTIR)─we probe the concentration-dependent interactions of C10-OU4 with lipid membranes that model Gram-positive bacterial membranes. At low concentrations (1 μM), C10-OU4 adsorbs to the membrane surface, inducing minor structural perturbations limited to the polar headgroup region. Increasing the concentration to 5 μM results in significant acyl chain disorder, partial membrane solubilization, and likely, micelle-like aggregate formation, as evidenced by QCM-D frequency shifts and ATR-FTIR data. At 10 μM, near the minimal inhibitory concentration, membrane disintegration becomes extensive, with the lipooligourea adopting orientations suggestive of random or tilted insertion geometries. These findings support a multimodal mechanism of action that transitions from surface association to full bilayer disruption in a concentration-dependent manner. The combined use of structural and dynamic measurements provides detailed insight into the physicochemical principles underlying lipooligourea-membrane interactions, offering a foundation for the rational design of membrane-active foldamer antibiotics.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-21","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144339694","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Tuning Microbasicity in Poly(vinyl alcohol) Films via Hydrogen-Bonding Network Disruption.","authors":"Siyu Hou, Qin Yu, Xiya Peng, Shufang Gao, Jian Luo","doi":"10.1021/acs.jpcb.5c03440","DOIUrl":"10.1021/acs.jpcb.5c03440","url":null,"abstract":"<p><p>The microstructural properties of poly(vinyl alcohol) (PVA) and its composites critically determine their mechanical and optoelectronic performance in flexible sensors, yet their micro acid-base characteristics remain poorly understood despite their importance for pH-responsive functionalities. Here, we report a combined experimental and theoretical study demonstrating that dimethyl sulfoxide (DMSO) incorporation significantly enhances the microbasicity of PVA films. By employing a fluorescent probe and density functional theory calculations, we established that DMSO disrupts water's hydrogen-bonding network, increasing the population of bound water with enhanced basicity. Furthermore, DMSO may also strengthen the hydrogen bonding between the lumichrome probe and bound water, promoting deprotonation. This work provides direct evidence that water with an unsaturated hydrogen-bonding network exhibits elevated basicity, which offers a simple yet effective strategy to tune PVA's acid-base properties. Our findings enable new design principles for advanced proton-transfer-based materials in flexible electronics and smart sensors.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144336123","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Unravelling the Thermophysical Properties of Trisodium Citrate and Disodium Tartrate in Aqueous 1-Ethyl-3-methylimidazolium Ethyl Sulfate Solutions: Insights from Volumetric, Acoustic, Viscometric and Computational Studies.","authors":"Himani Singh, Amir Fayaz, Richu, Akshita Bandral, Ashwani Kumar","doi":"10.1021/acs.jpcb.5c00871","DOIUrl":"10.1021/acs.jpcb.5c00871","url":null,"abstract":"<p><p>The research focuses on studying the thermophysical properties of trisodium citrate and disodium tartrate in aqueous solutions of 1-ethyl-3-methylimidazolium ethyl sulfate, i.e., (0.05, 0.10, and 0.15) mol kg^-1 at different temperatures. The experiment involved measuring density, sound speed, and viscosity to calculate various parameters related to volume, compressibility, and viscosity like apparent molar volumes (<i>V</i>_ϕ), partial molar volumes (<i>V</i>^o_ϕ), limiting apparent molar expansibilities (<i>E</i>^o_ϕ), apparent molar isentropic compressibilities (<i>K</i>_ϕ,s), transfer properties, hydration number (<i>n</i>_H), viscosity <i>B</i>-coefficients, and thermodynamic parameters of viscous flow (Δμ^o₁, Δμ^o₂, Δ<i>H</i>^o₂ and <i>T</i>Δ<i>S</i>^o₂), etc. These parameters were used to analyze the interactions between trisodium citrate and disodium tartrate and 1-ethyl-3-methylimidazolium ethyl sulfate in the aqueous medium. The results indicated the prevalence of hydrophilic-hydrophilic interactions in the systems under investigation. Additionally, the density functional theory (DFT) calculations were performed to explore further the interactions and the characteristics of the studied systems.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144336124","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Analysis of Proton NMR Transverse Magnetization Decay of Mixtures of Compounds and Semicrystalline Polymers: A Least-Squares Fit and the Inverse Laplace Transform.","authors":"Radu Fechete, Victor Litvinov","doi":"10.1021/acs.jpcb.5c01646","DOIUrl":"10.1021/acs.jpcb.5c01646","url":null,"abstract":"<p><p>The present study aimed to determine the strategy for analysis of NMR transverse magnetization decay (the <i>T</i>₂ decay) of semicrystalline polymers using two alternative methods, i.e., a least-squares fit of decays and their inverse Laplace transform (ILT). First, these methods are used to analyze the <i>T</i>₂ decay of one-phase compounds with physical states ranging from crystals (gypsum) to glassy polymer (polycarbonate, PC) and from amorphous EPDM vulcanizate to melts of PC and high-density polyethylene. Then, physical mixtures of these compounds are analyzed. Finally, the <i>T</i>₂ decay of isotactic polypropylene and propylene-ethylene random copolymers with complex physical structures is examined. For the study, a kernel of commonly used ILT software, which is applicable for the analysis of exponential functions, was modified by adding the Gaussian and the Abragamian functions that describe well the decay shape of glassy and crystalline compounds, respectively. To our knowledge, such a composite kernel has not been used before. This method was named the Laplace-like. The Laplace-like analysis offers advantages when the decay rate of different phases does not largely differ, e.g., in materials composed of crystals, glassy phases, and interfaces with restricted molecular mobility when deconvolution of <i>T</i>₂ decays with a least-squares method fails. The Laplace-like method can help to identify the number of polymer fractions with restricted chain mobility and distribution of specific (exponential, Gaussian, or Abragamian) <i>T</i>₂ relaxation times. However, the ILT method with the exponential kernel cannot provide meaningful data for soft polymeric matters. The reliable analysis requires implementation in the kernel of the Laplace algorithm complex functions describing the shape of NMR decays of soft polymeric matters and polymer melts. The advantages and limitations of a least-squares deconvolution of <i>T</i>₂ decays into their components and the Laplace-like method are discussed. The most reliable procedures for extracting information about the phase composition and molecular mobility in different phases of semicrystalline polymers were proposed.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144336122","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Molecular Insights into the Influence of Ions on the Water Structure. II. Halide Ions in Solution.","authors":"Henry Agnew, Roya Savoj, Richa Rashmi, Benjamin Savala, Francesco Paesani","doi":"10.1021/acs.jpcb.5c02745","DOIUrl":"10.1021/acs.jpcb.5c02745","url":null,"abstract":"<p><p>Understanding how halide ions affect the structure and dynamics of water at the molecular level is essential for a wide range of chemical, biological, and environmental processes. In this study, we use molecular dynamics simulations with MB-nrg data-driven many-body potential energy functions to investigate the hydration properties of halide ions in bulk water. The results reveal distinct trends in hydration structure, residence times, dipole moment distributions, and infrared spectral signatures, reflecting variations in ion size, charge density, and polarizability. In particular, fluoride promotes uniquely strong and more directional hydrogen bonds with the surrounding water molecules, which leads to substantial spectral shifts and slower water exchange dynamics. In contrast, heavier halides induce only minimal perturbations on the water hydrogen-bond network, even within the first hydration shell. These insights provide a quantitative framework for understanding ion-specific effects in aqueous systems and set the stage for future studies of more complex environments such as aqueous interfaces and confined systems.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":""},"PeriodicalIF":2.8,"publicationDate":"2025-06-20","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144332062","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Tianyu Li,&nbsp;Zhaoyun Chai*,&nbsp;Xiangyu Liu,&nbsp;Chang Xiao,&nbsp;Shuyan Wu and Lixia He,&nbsp;","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":"129 24","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":2.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.jpcb.5c01386","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144428998","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Maria Pechlaner*,&nbsp;Wilfred F. van Gunsteren,&nbsp;Lorna J. Smith and Niels Hansen,&nbsp;","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":"129 24","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":2.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.jpcb.5c03491","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144429013","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Mikhail A. Anisimov*,&nbsp;Sergey V. Buldyrev,&nbsp;Frédéric Caupin and Thomas J. Longo,&nbsp;","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":"129 24","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":2.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.jpcb.5c01744","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144429022","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"Efficient Multistate Free-Energy Calculations with QM/MM Accuracy Using Replica-Exchange Enveloping Distribution Sampling.","authors":"Domen Pregeljc, Ramon J R Hügli, Sereina Riniker","doi":"10.1021/acs.jpcb.5c02086","DOIUrl":"10.1021/acs.jpcb.5c02086","url":null,"abstract":"<p><p>Calculating free-energy differences using molecular dynamics (MD) simulations is an important task in computational chemistry. In practice, the accuracy of the results is limited by model approximations and insufficient phase-space sampling due to limited computational resources. In the present work, we address these challenges by integrating the quantum-mechanical/molecular-mechanical (QM/MM) scheme with replica-exchange enveloping distribution sampling (RE-EDS) to obtain a multistate and multiscale free-energy method with high computational efficiency. The performance of QM/MM RE-EDS is showcased by calculating hydration free energies for three data sets using semiempirical methods for the QM zone. We highlight the importance of the choice of QM Hamiltonian and the effect of the compatibility between the QM and MM models. Especially the choice of semiempirical method has a substantial effect on the accuracy compared to experiment, but also the choice of MM water model is non-negligible. Our findings indicate that RE-EDS is an efficient approach for calculating free-energy differences with a QM/MM scheme, and lays the foundation for future developments and applications.</p>","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":" ","pages":"5948-5960"},"PeriodicalIF":2.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://www.ncbi.nlm.nih.gov/pmc/articles/PMC12183765/pdf/","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144245360","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}

{"title":"","authors":"Philip L. Benjamin,&nbsp;Luca Gerhards,&nbsp;Ilia A. Solov’yov and P. J. Hore*,&nbsp;","doi":"","DOIUrl":"","url":null,"abstract":"","PeriodicalId":60,"journal":{"name":"The Journal of Physical Chemistry B","volume":"129 24","pages":"XXX-XXX XXX-XXX"},"PeriodicalIF":2.8,"publicationDate":"2025-06-19","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"https://pubs.acs.org/doi/pdf/10.1021/acs.jpcb.5c01187","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"144429001","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":2,"RegionCategory":"化学","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"OA","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}