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1.
Mol Med ; 30(1): 41, 2024 Mar 22.
Artigo em Inglês | MEDLINE | ID: mdl-38519941

RESUMO

BACKGROUND: Benign prostatic hyperplasia (BPH) is a prevalent disease affecting elderly men, with chronic inflammation being a critical factor in its development. Omentin-1, also known as intelectin-1 (ITLN-1), is an anti-inflammatory protein primarily found in the epithelial cells of the small intestine. This study aimed to investigate the potential of ITLN-1 in mitigating BPH by modulating local inflammation in the prostate gland. METHODS: Our investigation involved two in vivo experimental models. Firstly, ITLN-1 knockout mice (Itln-1-/-) were used to study the absence of ITLN-1 in BPH development. Secondly, a testosterone propionate (TP)-induced BPH mouse model was treated with an ITLN-1 overexpressing adenovirus. We assessed BPH severity using prostate weight index and histological analysis, including H&E staining, immunohistochemistry, and enzyme-linked immunosorbent assay. In vitro, the impact of ITLN-1 on BPH-1 cell proliferation and inflammatory response was evaluated using cell proliferation assays and enzyme-linked immunosorbent assay. RESULTS: In vivo, Itln-1-/- mice exhibited elevated prostate weight index, enlarged lumen area, and higher TNF-α levels compared to wild-type littermates. In contrast, ITLN-1 overexpression in TP-induced BPH mice resulted in reduced prostate weight index, lumen area, and TNF-α levels. In vitro studies indicated that ITLN-1 suppressed the proliferation of prostate epithelial cells and reduced TNF-α production in macrophages, suggesting a mechanism involving the inhibition of macrophage-mediated inflammation. CONCLUSION: The study demonstrates that ITLN-1 plays a significant role in inhibiting the development of BPH by reducing local inflammation in the prostate gland. These findings highlight the potential of ITLN-1 as a therapeutic target in the management of BPH.


Assuntos
Proteínas Ligadas por GPI , Lectinas , Hiperplasia Prostática , Animais , Masculino , Camundongos , Citocinas/genética , Citocinas/metabolismo , Proteínas Ligadas por GPI/genética , Proteínas Ligadas por GPI/metabolismo , Inflamação/patologia , Lectinas/genética , Lectinas/metabolismo , Extratos Vegetais/farmacologia , Próstata/metabolismo , Próstata/patologia , Hiperplasia Prostática/genética , Hiperplasia Prostática/tratamento farmacológico , Hiperplasia Prostática/metabolismo , Fator de Necrose Tumoral alfa
2.
Langmuir ; 40(10): 5444-5454, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38427794

RESUMO

Historically, research on silicotungstic-acid-based hydrogels has primarily focused on their adhesive properties, often at the expense of mechanical strength (cohesion). In this study, we present a novel approach to fabricate a polysaccharide hydrogel that harmoniously balances both adhesion and cohesion via interfacial hydrogen bonds. This hydrogel, composed of carboxymethyl cellulose (CMC), polyacrylamide (PAM), silicotungstic acid (SiW), and lithium chloride (LiCl), showcases a unique combination of properties: strain-responsive ionic conductivity, superior transparency, remarkable stretchability, and robust adhesion. Contrary to conventional PAM hydrogels, our PAM-SiW networked hydrogel addresses the common challenge of achieving good adhesion without compromising on cohesion. Specifically, our hydrogel demonstrates a maximum toughness of 20.3 MJ/m3 and a strain of 4079%, an accomplishment rarely observed in other adhesive hydrogel. Furthermore, the hydrogel's adhesion is both reversible and versatile, adhering effectively to a variety of wet and dry substrates. This makes it a promising candidate for advanced healthcare applications, particularly as a mechanically reinforced underwater adhesive with unparalleled stability. We also provide insights into the role of LiCl in the hydrogel matrix, emphasizing its influence on electrostatic interactions without affecting the hydrogen bonds. This study serves as a testament to the potential of harmonizing adhesive and cohesive properties in hydrogels, paving the way for future innovations in the field.

3.
Langmuir ; 2024 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-38330259

RESUMO

The prevention of biofilm formation on medical devices has become highly challenging in recent years due to its resistance to bactericidal agents and antibiotics, ultimately resulting in chronic infections to medical devices. Therefore, developing inexpensive, biocompatible, and covalently bonded coatings to combat biofilm formation is in high demand. Herein, we report a coating fabricated from tannic acid (TA) as an adhesive and a reducing agent to graft the zwitterionic polymer covalently in a one-step method. Subsequently, silver nanoparticles (AgNPs) are generated in situ to develop a coating with antifouling and antibacterial properties. To enhance the antifouling property and biocompatibility of the coating, the bioinspired zwitterionic 2-methacryloyloxyethyl phosphorylcholine (MPC) was copolymerized with 2-aminoethyl methacrylamide hydrochloride (AEMA) using conventional free-radical polymerization. AEMA moieties containing amino groups were used to facilitate the conjugation of the copolymer with quinone groups on TA through the Michael addition reaction. Three copolymers with different ratios of monomers were synthesized to understand their impacts on fouling resistance: PMPC100, p(MPC80-st-AEMA20), and p(MPC90-st-AEMA10). To impart antibacterial properties to the surface, AgNPs were formed in situ, utilizing the unreacted quinone groups on TA, which can reduce the silver ions. The successful coating of TA and copolymer onto the surfaces was confirmed by attenuated total reflectance Fourier transform infrared (ATR-FTIR) spectroscopy, and its excellent wettability was verified by the water contact angle (CA). Furthermore, the functionalized coatings showed antibacterial properties against E. coli and S. aureus and remarkably decreased the adhesion of the BSA protein. The surfaces can also prevent the adhesion of bacteria cells, as confirmed by the inhibition zone test. In addition, they showed negligible cytotoxicity to normal human lung fibroblast cells (MRC-5). The as-prepared coatings are potentially valuable for biomedical applications.

4.
Langmuir ; 40(21): 10957-10965, 2024 May 28.
Artigo em Inglês | MEDLINE | ID: mdl-38752656

RESUMO

Zwitterionic coatings provide a promising antifouling strategy against biofouling adhesion. Quaternary ammonium cationic polymers can effectively kill bacteria on the surface, owing to their positive charges. This strategy can avoid the release of toxic biocides, which is highly desirable for constructing coatings for biomedical devices. The present work aims to develop a facile method by covalently grafting zwitterionic and cationic copolymers containing aldehydes to the remaining amine groups of self-polymerized dopamine. Reversible addition-fragmentation chain transfer polymerization was used to copolymerize either zwitterionic 2-methacryloyloxyethyl phosphorylcholine monomer (MPC) or cationic 2-(methacryloyloxy)ethyl trimethylammonium monomer (META) with 4-formyl phenyl methacrylate monomer (FPMA), and the formed copolymers poly(MPC-st-FPMA) and poly(META-st-FPMA) are denoted as MPF and MTF, respectively. MPF and MTF copolymers were then covalently grafted onto the amino groups of polydopamine-coated surfaces. PDA/MPF/MTF-coated surfaces exhibited antibacterial and antifouling properties against S. aureus, E. coli, and bovine serum albumin protein. In addition, they showed excellent viability of normal human lung fibroblast cells MRC-5. We expect the facile surface modification strategy discussed here to be applicable to medical device manufacturing.


Assuntos
Antibacterianos , Polímeros , Staphylococcus aureus , Antibacterianos/farmacologia , Antibacterianos/química , Antibacterianos/síntese química , Polímeros/química , Polímeros/farmacologia , Staphylococcus aureus/efeitos dos fármacos , Animais , Incrustação Biológica/prevenção & controle , Escherichia coli/efeitos dos fármacos , Bivalves/química , Propriedades de Superfície , Materiais Revestidos Biocompatíveis/química , Materiais Revestidos Biocompatíveis/farmacologia , Fosforilcolina/análogos & derivados , Fosforilcolina/química , Fosforilcolina/farmacologia , Soroalbumina Bovina/química , Humanos , Metacrilatos/química , Metacrilatos/farmacologia , Aderência Bacteriana/efeitos dos fármacos , Indóis
5.
Langmuir ; 40(11): 5992-6003, 2024 Mar 19.
Artigo em Inglês | MEDLINE | ID: mdl-38445586

RESUMO

When the electric field strength (E) surpasses a certain threshold, secondary droplets are generated during the coalescence between water droplets in oil and the oil-water interface (so-called the droplet-interface partial coalescence phenomenon), resulting in a lower efficiency of droplet electrocoalescence. This study employs molecular dynamics (MD) simulations to investigate the droplet-interface partial coalescence phenomenon under direct current (DC) electric fields. The results demonstrate that intermolecular interactions, particularly the formation of hydrogen bonds, play a crucial role in dipole-dipole coalescence. Droplet-interface partial coalescence is categorized into five regimes based on droplet morphology. During the contact and fusion of the droplet with the water layer, the dipole moment of the droplet exhibits alternating increases and decreases along the electric field direction. Electric field forces acting on sodium ions and the internal interactions within droplets promote the process of droplet-interface partial coalescence. High field strengths cause significant elongation of the droplet, leading to its fragmentation into multiple segments. The migration of hydrated ions has a dual impact on the droplet-interface partial coalescence, with both facilitative and suppressive effects. The time required for droplet-interface partial coalescence initially decreases and subsequently increases as the field strength increases, depending on the competitive relationship between the extent of droplet stretching and the electric field force. This work provides molecular insights into the droplet-interface coalescence mechanisms in water-in-oil emulsions under DC electric fields.

6.
Chem Rev ; 122(18): 14594-14678, 2022 09 28.
Artigo em Inglês | MEDLINE | ID: mdl-36054924

RESUMO

Noncovalent interactions, which usually feature tunable strength, reversibility, and environmental adaptability, have been recognized as driving forces in a variety of biological and chemical processes, contributing to the recognition between molecules, the formation of molecule clusters, and the establishment of complex structures of macromolecules. The marriage of noncovalent interactions and conventional covalent polymers offers the systems novel mechanical, physicochemical, and biological properties, which are highly dependent on the binding mechanisms of the noncovalent interactions that can be illuminated via quantification. This review systematically discusses the nanomechanical characterization of typical noncovalent interactions in polymeric systems, mainly through direct force measurements at microscopic, nanoscopic, and molecular levels, which provide quantitative information (e.g., ranges, strengths, and dynamics) on the binding behaviors. The fundamental understandings of intermolecular and interfacial interactions are then correlated to the macroscopic performances of a series of noncovalently bonded polymers, whose functions (e.g., stimuli-responsiveness, self-healing capacity, universal adhesiveness) can be customized through the manipulation of the noncovalent interactions, providing insights into the rational design of advanced materials with applications in biomedical, energy, environmental, and other engineering fields.


Assuntos
Fenômenos Mecânicos , Polímeros , Substâncias Macromoleculares/química , Polímeros/química
7.
Environ Sci Technol ; 2024 Jan 22.
Artigo em Inglês | MEDLINE | ID: mdl-38247403

RESUMO

The mobility and distribution of heavy metal ions (HMs) in aquatic environments are significantly influenced by humic acid (HA), which is ubiquitous. A quantitative understanding of the interaction mechanism underlying the adsorption and retention of HMs by HA is of vital significance but remains elusive. Herein, the interaction mechanism between HA and different types of HMs (i.e., Cd(II), Pb(II), arsenate, and chromate) was quantitatively investigated at the nanoscale. Based on quartz crystal microbalance with dissipation tests, the adsorption capacities of Pb(II), Cd(II), As(V), and Cr(VI) ionic species on the HA surface were measured as ∼0.40, ∼0.25, ∼0.12, and ∼0.02 nmol cm-2, respectively. Atomic force microscopy force results showed that the presence of Pb(II)/Cd(II) cations suppressed the electrostatic double-layer repulsion during the approach of two HA surfaces and the adhesion energy during separation was considerably enhanced from ∼2.18 to ∼5.05/∼4.18 mJ m-2. Such strong adhesion stems from the synergistic metal-HA complexation and cation-π interaction, as evidenced by spectroscopic analysis and theoretical simulation. In contrast, As(V)/Cr(VI) oxo-anions could form only weak hydrogen bonds with HA, resulting in similar adhesion energies for HA-HA (∼2.18 mJ m-2) and HA-As(V)/Cr(VI)-HA systems (∼2.26/∼1.96 mJ m-2). This work provides nanoscale insights into quantitative HM-HA interactions, improving the understanding of HMs biogeochemical cycling.

8.
Macromol Rapid Commun ; : e2400276, 2024 Jul 19.
Artigo em Inglês | MEDLINE | ID: mdl-39031940

RESUMO

Lubricant-infused slippery surfaces have recently emerged as promising antifouling coatings, showing potential against proteins, cells, and marine mussels. However, a comprehensive understanding of the molecular binding behaviors and interaction strength of foulants to these surfaces is lacking. In this work, mussel-inspired chemistry based on catechol-containing chemicals including 3,4-dihydroxyphenylalanine (DOPA) and polydopamine (PDA) is employed to investigate the antifouling performance and repellence mechanisms of fluorinated-based slippery surface, and the correlated interaction mechanisms are probed using atomic force microscopy (AFM). Intermolecular force measurements and deposition experiments between PDA and the surface reveal the ability of lubricant film to inhibit the contact of PDA particles with the substrate. Moreover, the binding mechanisms and bond dissociation energy between a single DOPA moiety and the lubricant-infused slippery surface are quantitatively investigated employing single-molecule force spectroscopy based on AFM (SM-AFM), which reveal that the infused lubricant layer can remarkably influence the dissociation forces and weaken the binding strength between DOPA and underneath per-fluorinated monolayer surface. This work provides new nanomechanical insights into the fundamental antifouling mechanisms of the lubricant-infused slippery surfaces against mussel-derived adhesive chemicals, with important implications for the design of lubricant-infused materials and other novel antifouling platforms for various bioengineering and engineering applications.

9.
Macromol Rapid Commun ; : e2400362, 2024 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-39078623

RESUMO

The flexible electronic sensor is a critical component of wearable devices, generally requiring high stretchability, excellent transmittance, conductivity, self-healing capability, and strong adhesion. However, designing ion-conducting elastomers meeting all these requirements simultaneously remains a challenge. In this study, a novel approach is presented to fabricate highly stretchable, transparent, and self-healing ion-conducting elastomers, which are synthesized via photo-polymerization of two polymerizable deep eutectic solvents (PDESs) monomers, i.e., methacrylic acid (MAA)/choline chloride (ChCl) and itaconic acid (IA)/ChCl. The as-prepared ion-conducting elastomers possess outstanding properties, including high transparency, conductivity, and the capability to adhere to various substrates. The elastomers also demonstrate ultra-stretchability (up to 3900%) owing to a combination of covalent cross-linking and noncovalent cross-linking. In addition, the elastomers can recover up to 3250% strain and over 94.5% of their original conductivity after self-healing at room temperature for 5 min, indicating remarkable mechanical and conductive self-healing abilities. When utilized as strain sensors to monitor real-time motion of human fingers, wrist, elbow, and knee joints, the elastomers exhibit stable and strong repetitive electrical signals, demonstrating excellent sensing performance for large-scale movements of the human body. It is anticipated that these ion-conducting elastomers will find promising applications in flexible and wearable electronics.

10.
J Chem Phys ; 161(1)2024 Jul 07.
Artigo em Inglês | MEDLINE | ID: mdl-38949280

RESUMO

In this work, we performed static density functional theory calculations and ab initio metadynamics simulations to systematically investigate the association mechanisms and dynamic structures of four kinds of ion pairs that could be formed before the nucleation of CaCO3. For Ca2+-HCO3- and Ca2+-CO32- pairs, the arrangement of ligands around Ca2+ evolves between the six-coordinated octahedral structure and the seven-coordinated pentagonal bipyramidal structure. The formation of ion pairs follows an associative ligand substitution mechanism. Compared with HCO3-, CO32- exhibits a stronger affinity to Ca2+, leading to the formation of a more stable precursor phase in the prenucleation stage, which promotes the subsequent CaCO3 nucleation. In alkaline environments, excessive OH- ions decrease the coordination preference of Ca2+. In this case, the formation of Ca(OH)+-CO32- and Ca(OH)2-CO32- pairs favors the dissociative ligand substitution mechanism. The inhibiting effects of OH- ion on the CaCO3 association can be interpreted from two aspects, i.e., (1) OH- neutralizes positive charges on Ca2+, decreases the electrostatic interactions between Ca2+ and CO32-, and thus hinders the formation of the CaCO3 monomer, and (2) OH- decreases the capacity of Ca2+ for accommodating O, making it easier to separate Ca2+ and CO32- ions. Our findings on the ion association behaviors in the initial stage of CaCO3 formation not only help scientists evaluate the impact of ocean acidification on biomineralization but also provide theoretical support for the discovery and development of more effective approaches to manage undesirable scaling issues.

11.
J Environ Manage ; 354: 120342, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38382431

RESUMO

In this work, ultraviolet irradiation was employed to assist in the preparation of a novel photocatalyst composite in the form of carbon dots/zeolite-4A/TiO2, using coal tailings as the source of silicon-aluminum and carbon. The composite was designed for the degradation of methylene blue under 500 W of UV light irradiation. Zeolite-4A was used as a support for the well-dispersed carbon dots and TiO2 nanoparticles. The as-prepared composites were subjected to thorough characterization, confirming the successful formation of zeolite-4A with a cube structure, along with the loading of TiO2 and coal-based CDs in the composites. The experimental results demonstrated that the UV-CZTs nanocomposites exhibited a remarkable removal efficiency of 90.63% within 90 min for MB. The corresponding rate constant was exceptionally high at 0.0331 min-1, surpassing that of the Dark-CZTs and pure TiO2. This significant enhancement was possibly due to the synergistic effect of adsorption photocatalysis of the UV-CZTs, combined with the excellent electron-accepting capabilities of the coal-based CDs, which led to highly improved charge separation. An investigation of the spent photocatalyst's recyclability revealed that it retained a remarkable 82.94% MB removal efficiency after five consecutive cycles, signifying the stability of the composite. Trapping experiments also elucidated the primary reactive species responsible for MB degradation, which were identified as photo-generated holes and ⸱O2- species. By this process, the hydroxyl radicals generated in the system successfully promoted the transformation of coal tailings to coal-based zeolite and coal-based CDs. Coal-based zeolite served as an excellent carrier of titanium dioxide, which improved its dispersibility. The inhibition of e--h+ recombination of titanium dioxide by introducing coal-based CDs improved the photocatalytic ability of titanium dioxide. Through this study, coal tailings, as a coal processing waste, were transformed into high-value materials, and relevant photocatalytic composite materials could be prepared with broad application prospects.


Assuntos
Raios Ultravioleta , Zeolitas , Corantes , Zeolitas/química , Titânio/química , Carvão Mineral , Carbono , Catálise
12.
J Environ Sci (China) ; 138: 112-120, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38135380

RESUMO

Zeolitic Imidazolate Framework-8 (ZIF-8) material was prepared by chemical precipitation method. The microstructure and physical properties of the as-prepared samples were characterized by XRD, BET, FESEM and UV spectrophotometer. The self-made four-channel measurement device was used to test the gas sensitivity of ZIF-8 material toward ethanol gas under photo-thermal synergistic excitation. The results showed that the sample was typical ZIF-8 (Eg = 4.96 eV) with a regular dodecahedron shape and the specific surface is up to 1793 m2/g. The as-prepared ZIF-8 has a gas response value of 55.04 to 100 ppm ethanol at 75°C and it shows good gas sensing selectivity and repeated stability. The excellent gas sensitivity can be attributed to the increase of free electron concentration in the ZIF-8 conduction band by photo-thermal synergistic excitation, and the large specific surface area of ZIF-8 material provides more active sites for gas-solid surface reaction. The reaction mechanism of ZIF-8 material under multi-field excitation was also discussed.


Assuntos
Imidazóis , Zeolitas , Temperatura , Zeolitas/química , Temperatura Baixa
13.
Acc Chem Res ; 55(8): 1171-1182, 2022 04 19.
Artigo em Inglês | MEDLINE | ID: mdl-35344662

RESUMO

Supramolecular assembly is commonly driven by noncovalent interactions (e.g., hydrogen bonding, electrostatic, hydrophobic, and aromatic interactions) and plays a predominant role in multidisciplinary research areas ranging from materials design to molecular biology. Understanding these noncovalent interactions at the molecular level is important for studying and designing supramolecular assemblies in chemical and biological systems. Cation-π interactions, initially found through their influence on protein structure, are generally formed between electron-rich π systems and cations (mainly alkali, alkaline-earth metals, and ammonium). Cation-π interactions play an essential role in many biological systems and processes, such as potassium channels, nicotinic acetylcholine receptors, biomolecular recognition and assembly, and the stabilization and function of biomacromolecular structures. Early fundamental studies on cation-π interactions primarily focused on computational calculations, protein crystal structures, and gas- and solid-phase experiments. With the more recent development of spectroscopic and nanomechanical techniques, cation-π interactions can be characterized directly in aqueous media, offering opportunities for the rational manipulation and incorporation of cation-π interactions into the design of supramolecular assemblies. In 2012, we reported the essential role of cation-π interactions in the strong underwater adhesion of Asian green mussel foot proteins deficient in l-3,4-dihydroxyphenylalanine (DOPA) via direct molecular force measurements. In another study in 2013, we reported the experimental quantification and nanomechanics of cation-π interactions of various cations and π electron systems in aqueous solutions using a surface forces apparatus (SFA).Over the past decade, much progress has been achieved in probing cation-π interactions in aqueous solutions, their impact on the underwater adhesion and cohesion of different soft materials, and the fabrication of functional materials driven by cation-π interactions, including surface coatings, complex coacervates, and hydrogels. These studies have demonstrated cation-π interactions as an important driving force for engineering functional materials. Nevertheless, compared to other noncovalent interactions, cation-π interactions are relatively less investigated and underappreciated in governing the structure and function of supramolecular assemblies. Therefore, it is imperative to provide a detailed overview of recent advances in understanding of cation-π interactions for supramolecular assembly, and how these interactions can be used to direct supramolecular assembly for various applications (e.g., underwater adhesion). In this Account, we present very recent advances in probing and applying cation-π interactions for mussel-inspired supramolecular assemblies as well as their structural and functional characteristics. Particular attention is paid to experimental characterization techniques for quantifying cation-π interactions in aqueous solutions. Moreover, the parameters responsible for modulating the strengths of cation-π interactions are discussed. This Account provides useful insights into the design and engineering of smart materials based on cation-π interactions.


Assuntos
Hidrogéis , Proteínas , Cátions/química , Hidrogéis/química , Ligação de Hidrogênio , Proteínas/química , Eletricidade Estática , Água
14.
Chemphyschem ; 24(3): e202200608, 2023 Feb 01.
Artigo em Inglês | MEDLINE | ID: mdl-36173980

RESUMO

Chirality discrimination at a binary toluene (organic)/water(aqueous) interface between R- or S-Tol-BINAP (2,2'-Bis(di-p-tolylphosphino)-1,1'-binaphthyl) molecules and the water-soluble serine chiral specie is examined for the first time, using a combination of interfacial tension measurements and molecular dynamic simulations. Experimental interfacial measurements exhibit a clear chirality-controlled difference when a homochiral versus a heterochiral enantiomeric pairs are introduced at the interfaces. The related molecular dynamics simulations support the experimental results and provide further molecular insight of intermolecular interactions at the interfaces. The results indicate that interfacial tension measurements can capture the preferential interactions which exist between different pairs of enantiomers at the binary interfaces, opening up a new way for probing chirality discrimination at liquid-liquid interfaces.

15.
Langmuir ; 39(6): 2233-2245, 2023 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-36734483

RESUMO

Water droplets in crude oil can be stabilized by the adsorption of interfacially active components, such as asphaltenes. Demulsifiers like non-ionic surfactants are commonly used to destabilize the water-in-oil emulsions. In this work, molecular dynamics simulations and free energy calculations were performed to study the coalescence of water droplets coated with both model asphaltene and non-ionic surfactants [PEO-PPO-PEO copolymer (SurP) or Brij surfactant (SurB)]. For the first time, we quantitatively studied the interaction force between water droplets in the presence of both asphaltenes and demulsifiers and addressed the effect of solvent property on the coalescence process. At the droplet surface, demulsifiers adsorbed closer to the water phase and formed more hydrogen bonds with water molecules compared to asphaltenes, indicating the capability of demulsifiers to break the asphaltene film. Comparing the two non-ionic surfactants, VO-79/SurP complexes formed a single-layer film on the droplet surface, while a two-layer structure was formed by VO-79/SurB complexes. This led to a higher repulsive force during droplet coalescence when SurB was present, regardless of the type of solvent. Comparing the two different solvents (toluene vs heptane), for the same adsorbates, the interfacial film was more compact in heptane and there were fewer dispersed VO-79. For VO-79/SurB adsorbates, the bridging of VO-79 led to a smaller repulsion during droplet coalescence when the solvent was heptane, while the difference is insignificant for VO-79/SurP adsorbates. This work suggests that the energy barrier and interaction force for droplet coalescence is highly dependent on the structure of interfacial films, thus providing atomic-level insights into the demulsification mechanisms of water-in-oil emulsions in the presence of surface-active asphaltenes.

16.
Langmuir ; 39(49): 17600-17610, 2023 12 12.
Artigo em Inglês | MEDLINE | ID: mdl-38039395

RESUMO

Cation-π interaction is one of the most important noncovalent interactions identified in biosystems, which has been proven to play an essential role in the strong adhesion of marine mussels. In addition to the well-known catecholic amino acid, l-3,4-dihydroxyphenylalanine, mussel foot proteins are rich in various aromatic moieties (e.g., tyrosine, phenylalanine, and tryptophan) and cationic residues (e.g., lysine, arginine, and histidine), which favor a series of short-range cation-π interactions with adjustable strengths, serving as a prototype for the development of high-performance underwater adhesives. This work highlights our recent advances in understanding and utilizing cation-π interactions in underwater adhesives, focusing on three aspects: (1) the investigation of the cation-π interaction mechanisms in mussel foot proteins via force-measuring techniques; (2) the modulation of cation-π interactions in mussel mimetic polymers with the variation of cations, anions, and aromatic groups; (3) the design of wet adhesives based on these revealed principles, leading to functional materials in the form of films, coacervates, and hydrogels with biomedical and engineering applications. This review provides valuable insights into the development and optimization of smart materials based on cation-π interactions.


Assuntos
Materiais Biomiméticos , Bivalves , Animais , Materiais Biomiméticos/química , Proteínas/química , Adesivos/química , Di-Hidroxifenilalanina/química , Cátions/química , Bivalves/química
17.
Environ Sci Technol ; 57(24): 9032-9042, 2023 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-37289238

RESUMO

Humic acid (HA) is ubiquitous in both terrestrial and aquatic environments, and understanding the molecular interaction mechanisms underlying its aggregation and adsorption is of vital significance. However, the intermolecular interactions of HA-HA and HA-clay mineral systems in complex aqueous environments remain elusive. Herein, the interactions of HA with various model surfaces (i.e., HA, mica, and talc) were quantitatively measured in aqueous media at the nanoscale using an atomic force microscope. The HA-HA interaction was found to be purely repulsive during surface approach, consistent with free energy calculation; during retraction, pH-dependent adhesion was observed due to the protonation/deprotonation of HA that influences the formation of hydrogen bonds. Different from the mica case, hydrophobic interaction was detected for the HA-talc system at pH 5.8, contributing to the stronger HA-talc adhesion, as also evidenced by adsorption results. Notably, HA-mica adhesion strongly depended on the loading force and contact time, most likely because of the short-range and time-dependent interfacial hydrogen bonding interaction under confinement, as compared to the dominant hydrophobic interaction for the HA-talc case. This study provides quantitative insights into the fundamental molecular interaction mechanisms underlying the aggregation of HA and its adsorption on clay minerals of varying hydrophobicity in environmental processes.


Assuntos
Substâncias Húmicas , Talco , Substâncias Húmicas/análise , Argila , Adsorção , Minerais/química
18.
Nano Lett ; 22(23): 9327-9334, 2022 12 14.
Artigo em Inglês | MEDLINE | ID: mdl-36449360

RESUMO

Here we present an innovative, universal, scalable, and straightforward strategy for cultivating a resilient, flexible lithium-ion battery (LIB) based on the bacterial-based self-growing approach. The electrodes and separator layers are integrated intrinsically into one unity of sandwich bacterial cellulose integrated film (SBCIF), with various active material combinations and tailored mechanical properties. The flexible LIB thereof showcases prominent deformation tolerance and multistage foldability due to the unique self-generated wavy-like structure. The LTO|LFP (Li4Ti5O12 and LiFePO4) SBCIF-based flexible LIB demonstrates reliable long-term electrochemical stability with high flexibility, by exhibiting a high capacity retention (>95%) after 500 cycles at 1C/1C after experiencing a 10 000 bending/flattening treatment. The LTO|LFP SBCIF battery subjected to a simultaneous bending/flattening and cycling experiment shows an extraordinary capacity retention rate (>68%) after 200 cycles at 1C/1C. The biobased self-growing approach offers an exciting and promising pathway toward the tailored, integrated high-performance flexible LIBs.


Assuntos
Fontes de Energia Elétrica , Lítio , Íons , Eletrodos , Celulose
19.
Angew Chem Int Ed Engl ; 62(29): e202305552, 2023 Jul 17.
Artigo em Inglês | MEDLINE | ID: mdl-37220309

RESUMO

The in situ exsolution technique of nanoparticles has brought new opportunities for the utilization of perovskite-based catalysts in solid oxide cells. However, the lack of control over the structural evolution of host perovskites during the promotion of exsolution has restricted the architectural exploitation of exsolution-facilitated perovskites. In this study, we strategically broke the long-standing trade-off phenomenon between promoted exsolution and suppressed phase transition via B-site supplement, thus broadening the scope of exsolution-facilitated perovskite materials. Using carbon dioxide electrolysis as an illustrative case study, we demonstrate that the catalytic activity and stability of perovskites with exsolved nanoparticles (P-eNs) can be selectively enhanced by regulating the explicit phase of host perovskites, accentuating the critical role of the architectures of perovskite scaffold in catalytic reactions occurring on P-eNs. The concept demonstrated could potentially pave the way for designing the advanced exsolution-facilitated P-eNs materials and unveiling a wide range of catalytic chemistry taking place on P-eNs.

20.
Langmuir ; 38(43): 12999-13008, 2022 11 01.
Artigo em Inglês | MEDLINE | ID: mdl-36260819

RESUMO

Nature offers inspiration for the development of high-performance synthetic materials. Extensive studies on the universal adhesion and self-healing behavior of mussel byssus reveal that a series of reversible molecular interactions occurring in byssal plaques and threads play an essential role, and the mussel-inspired chemistry can serve as a versatile platform for the design of self-healing materials. In this Perspective, we provide an overview of the recent progress in the detection, quantification, and utilization of mussel-inspired reversible molecular interactions, which includes the elucidation of their binding mechanisms via force-measuring techniques and the development of self-healing materials based on these dynamic interactions. Both conventional catechol-medicated interactions and newly discovered chemistry beyond the catechol groups are discussed, providing insights into the design strategies of advanced self-healing materials via mussel-inspired chemistry.


Assuntos
Bivalves , Animais , Bivalves/química , Catecóis/química , Software
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