Insight into molecular-level interactions between imidazolium-based ionic liquids and cellulose combining NMR, SAXS and MD simulations

Unique LCST phase behaviour of imidazolium-based ionic liquids is reported, which can be controlled by concentration, the choice of cation, anion and solvent, and by supramolecular complex formation. MD simulations provide insight into the molecular basis of this LCST phenomenon.

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Dynamics of Ion Locking in Doubly Polymerized Ionic Liquids

10.26434/chemrxiv.13239059.v1 ◽

2020 ◽

Author(s):

Swati Arora ◽

Julisa Rozon ◽

Jennifer Laaser

Keyword(s):

Dielectric Constant ◽

Ionic Liquid ◽

Ionic Liquids ◽

Ion Pairs ◽

Polymer Chains ◽

Ion Motion ◽

Charged Species ◽

Broadband Dielectric Spectroscopy ◽

Covalently Linked ◽

Insight Into

<div>In this work, we investigate the dynamics of ion motion in “doubly-polymerized” ionic liquids (DPILs) in which both charged species of an ionic liquid are covalently linked to the same polymer chains. Broadband dielectric spectroscopy is used to characterize these materials over a broad frequency and temperature range, and their behavior is compared to that of conventional “singly-polymerized” ionic liquids (SPILs) in which only one of the charged species is attached to the polymer chains. Polymerization of the DPIL decreases the bulk ionic conductivity by four orders of magnitude relative to both SPILs. The timescales for local ionic rearrangement are similarly found to be approximately four orders of magnitude slower in the DPILs than in the SPILs, and the DPILs also have a lower static dielectric constant. These results suggest that copolymerization of the ionic monomers affects ion motion on both the bulk and the local scales, with ion pairs serving to form strong physical crosslinks between the polymer chains. This study provides quantitative insight into the energetics and timescales of ion motion that drive the phenomenon of “ion locking” currently under investigation for new classes of organic electronics.</div>

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Molecular-Level Investigation of Cycloaliphatic Epoxidised Ionic Liquids as a New Generation of Monomers for Versatile Poly(Ionic Liquids)

Polymers ◽

10.3390/polym13091512 ◽

2021 ◽

Vol 13 (9) ◽

pp. 1512

Author(s):

Baris Demir ◽

Gabriel Perli ◽

Kit-ying Chan ◽

Jannick Duchet-Rumeau ◽

Sébastien Livi

Keyword(s):

Ionic Liquids ◽

Molecular Level ◽

Computational Approach ◽

Polymer Materials ◽

Chemical Structures ◽

Cycloaliphatic Epoxy ◽

Polymer Models ◽

Mechanical Performances ◽

Dynamics Simulations ◽

New Generation

Recently, a new generation of polymerised ionic liquids with high thermal stability and good mechanical performances has been designed through novel and versatile cycloaliphatic epoxy-functionalised ionic liquids (CEILs). From these first promising results and unexplored chemical structures in terms of final properties of the PILs, a computational approach based on molecular dynamics simulations has been developed to generate polymer models and predict the thermo–mechanical properties (e.g., glass transition temperature and Young’s modulus) of experimentally investigated CEILs for producing multi-functional polymer materials. Here, a completely reproducible and reliable computational protocol is provided to design, test and tune poly(ionic liquids) based on epoxidised ionic liquid monomers for future multi-functional thermoset polymers.

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Noni fruit’s water spot appearance on the second day of harvest: a trade-off between resistance and energy

Chemical and Biological Technologies in Agriculture ◽

10.1186/s40538-020-00207-2 ◽

2021 ◽

Vol 8 (1) ◽

Author(s):

Tian Wu ◽

Danyan Hu ◽

Qingfen Wang

Keyword(s):

Statistical Analysis ◽

Molecular Level ◽

Morinda Citrifolia ◽

Transcriptome Data ◽

Trade Off ◽

Kegg Pathways ◽

Available Energy ◽

Climacteric Fruit ◽

The Relationship ◽

Insight Into

Abstract Background Noni (Morinda citrifolia Linn.) is a tropical tree that bears climacteric fruit. Previous observations and research have shown that the second day (2 d) after harvest is the most important demarcation point when the fruit has the same appearance as the freshly picked fruit (0 d); however, they are beginning to become water spot appearance. We performed a conjoint analysis of metabolome and transcriptome data for noni fruit of 0 d and 2 d to reveal what happened to the fruit at the molecular level. Genes and metabolites were annotated to KEGG pathways and the co-annotated KEGG pathways were used as a statistical analysis. Results We found 25 pathways that were significantly altered at both metabolic and transcriptional levels, including a total of 285 differentially expressed genes (DEGs) and 11 differential metabolites through an integrative analysis of transcriptomics and metabolomics. The energy metabolism and pathways originating from phenylalanine were disturbed the most. The upregulated resistance metabolites and genes implied the increase of resistance and energy consumption in the postharvest noni fruit. Most genes involved in glycolysis were downregulated, further limiting the available energy. This lack of energy led noni fruit to water spot appearance, a prelude to softening. The metabolites and genes related to the resistance and energy interacted and restricted each other to keep noni fruit seemingly hard within two days after harvest, but actually the softening was already unstoppable. Conclusions This study provides a new insight into the relationship between the metabolites and genes of noni fruit, as well as a foundation for further clarification of the post-ripening mechanism in noni fruit.

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Cisplatin under oriented external electric fields: A deeper insight into electrochemotherapy at the molecular level

International Journal of Quantum Chemistry ◽

10.1002/qua.26578 ◽

2020 ◽

Author(s):

Li Zhang ◽

Ya‐Ling Ye ◽

Xiao‐Ling Zhang ◽

Xiang‐Hui Li ◽

Qiao‐Hong Chen ◽

...

Keyword(s):

Electric Fields ◽

Molecular Level ◽

External Electric Fields ◽

Insight Into

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Elucidating sequence and solvent specific design targets to protect and stabilize enzymes for biocatalysis in ionic liquids

Physical Chemistry Chemical Physics ◽

10.1039/c7cp03013d ◽

2017 ◽

Vol 19 (26) ◽

pp. 17426-17433 ◽

Cited By ~ 14

Author(s):

K. G. Sprenger ◽

J. G. Plaks ◽

J. L. Kaar ◽

J. Pfaendtner

Keyword(s):

Ionic Liquids ◽

Structure Function ◽

Molecular Level ◽

Specific Design ◽

Host Environment ◽

Host Interactions

For many different frameworks, the structure, function, and dynamics of an enzyme is largely determined by the nature of its interactions with the surrounding host environment, thus a molecular level understanding of enzyme/host interactions is essential to the design of new processes and applications.

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Effect of Ionic Liquids on the Physical Properties of the Newly Synthesized Conducting Polymer

International Journal of Polymer Science ◽

10.1155/2018/8275985 ◽

2018 ◽

Vol 2018 ◽

pp. 1-8 ◽

Cited By ~ 1

Author(s):

Dong Uk Lee ◽

Jin Yeong Jeong ◽

Ji Woong Han ◽

Gi-Chung Kwon ◽

Pankaj Attri ◽

...

Keyword(s):

Raman Spectroscopy ◽

Ionic Liquids ◽

Conducting Polymer ◽

Optical Devices ◽

Polymer Mixtures ◽

Confocal Raman Spectroscopy ◽

Vis Spectroscopy ◽

Film Roughness ◽

Confocal Raman ◽

Insight Into

Conducting polymer has many applications in electronics, optical devices, sensors, and so on; however, there is still a massive scope of improvement in this area. Therefore, towards this aim, in this study, we synthesized a new thiophene-based conducting polymer, 2-heptadecyl-5-hexyl-6-(5-methylthiophen-2-yl)-4-(5-((E)-prop-1-enyl)thiophen-2-yl)-5H-pyrrolo[3,4-d]thiazole (HHMPT). Further, to increase its application, the interactions between the conducting polymer (HHMPT) and ionic liquids (ILs) were investigated by UV-Vis spectroscopy, FTIR spectroscopy, and confocal Raman spectroscopy techniques. Moreover, film roughness and conductivity of the polymer film with or without ILs were also studied. The imidazolium- and ammonium family ILs with the potential to interact with the newly synthesized conducting polymer were used. The results of the interaction studies revealed that the imidazolium family IL-polymer mixtures and ammonium family IL-polymer mixtures have almost similar conductivity at low concentration of ILs. This study provides an insight into the combined effect of a polymer and ILs and may generate many theoretical and experimental opportunities.

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On the interface of organic aerosols: molecular level understanding of surface melting, mixing and water adsorption/desorption dynamics

10.5194/egusphere-egu21-8258 ◽

2021 ◽

Author(s):

Josip Lovrić ◽

Xiangrui Kong ◽

Sofia M. Johansson ◽

Erik S. Thomson ◽

Jan B. C. Pettersson

Keyword(s):

Physical Chemistry ◽

Molecular Dynamics ◽

Melting Point ◽

Molecular Beam ◽

Molecular Level ◽

Organic Aerosols ◽

Md Simulations ◽

Valeric Acid ◽

Good Representative ◽

Hydrophilic Character

The detailed description of organic aerosols surfaces in the atmosphere remains an open issue, which limits our ability to understand and predict environmental change. Important research questions concern the hydrophobic/hydrophilic character of fresh and aged aerosols and the related influence on water uptake in solid, liquid as well in intermediate state. &#160;Also, surface characterization remains big challenge but we find it reachable by conjunction of Molecular Dynamics (MD) simulations and the environmental molecular beam (EMB) experimental method.&#160; A &#160;picture of the detailed molecular-level behavior of water molecules on organic surfaces is beginning to rise based on detailed experimental and theoretical studies; one example is a recent study that investigates water interactions with solid and liquid n-butanol near the melting point [1], another example focus on interaction of water with solid nopinone [2]. From the other side, in order to characterize surface properties during and before melting we employ MD simulations of n-butanol, nopinone and valeric acid. Nopinone (C9H14O) is a reaction product formed during oxidation of &#946;-pinene and has been found in both the gas and particle phases of atmospheric aerosol. n-butanol (C4H9OH) is primary alcohol, naturally occurs scarcely and here serves as good representative for alcohols. In the same way valeric acid (CH3(CH2)3COOH) serves as a good representative for a family of carboxylic acids. Valeric acid is, as n-butanol, straight-chain molecule. We show that a classical force field for organic material is able to model crystal and liquid structures. The surface properties near the melting point of the condensed phase are reported, and the hydrophobic and hydrophilic character of the surface layer is discussed. &#160;Overall surface melting dynamic is presented and quantified in the terms of structural and geometrical properties. Mixing of a methanol with the solid nopinone surface is examined and hereby presented.References[1] Johansson, S. M., Lovri&#263;, J., Kong, X., Thomson, E. S., Papagiannakopoulos, P., Briquez, S., Toubin, C, Pettersson, J. B. C. (2019). Understanding water interactions with organic surfaces: environmental molecular beam and molecular dynamics studies of the water&#8211;butanol system. Physical Chemistry Chemical Physics. https://doi.org/10.1039/C8CP04151B&#160;&#160;&#160;[2] Johansson, S. M., Lovri&#263;, J., Kong, X., Thomson, E. S., Hallquist, M., & Pettersson, J. B. C. (2020). Experimental and Computational Study of Molecular Water Interactions with Condensed Nopinone Surfaces Under Atmospherically Relevant Conditions. The Journal of Physical Chemistry A, acs.jpca.9b10970. https://doi.org/10.1021/acs.jpca.9b10970Keywords: Molecular Dynamics, organic crystal, organic aerosols, water uptake, surface procesess, molecular level

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Insight into Inhibitor Binding in the Eukaryotic Proteasome: Computations of the 20S CP

International Journal of Molecular Sciences ◽

10.3390/ijms19123858 ◽

2018 ◽

Vol 19 (12) ◽

pp. 3858

Author(s):

Milan Hodošček ◽

Nadia Elghobashi-Meinhardt

Keyword(s):

Electrostatic Interactions ◽

Active Sites ◽

Sampling Period ◽

Md Simulations ◽

Structural Features ◽

Relaxation Dynamics ◽

Inhibitor Binding ◽

Computational Analyses ◽

Insight Into ◽

Proteolytic Chamber

A combination of molecular dynamics (MD) simulations and computational analyses uncovers structural features that may influence substrate passage and exposure to the active sites within the proteolytic chamber of the 20S proteasome core particle (CP). MD simulations of the CP reveal relaxation dynamics in which the CP slowly contracts over the 54 ns sampling period. MD simulations of the SyringolinA (SylA) inhibitor within the proteolytic B 1 ring chamber of the CP indicate that favorable van der Waals and electrostatic interactions account for the predominant association of the inhibitor with the walls of the proteolytic chamber. The time scale required for the inhibitor to travel from the center of the proteolytic chamber to the chamber wall is on the order of 4 ns, accompanied by an average energetic stabilization of approximately −20 kcal/mol.

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