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The expandable graphite (EG) modified TiO2 nanocomposites were prepared by the high shear method using the TiO2 nanoparticles (NPs) and EG as precursors, in which the amount of EG doped in TiO2 was 10 wt.%. Followed by the impregnation method, adjusting the pH of the solution to 10, and using the electrostatic adsorption to achieve spatial confinement, the Pt elements were mainly distributed on the exposed TiO2, thus generating the Pt/10EG-TiO2-10 catalyst. The best CO oxidation activity with the excellent resistance to H2O and SO2 was obtained over the Pt/10EG-TiO2-10 catalyst: CO conversion after 36 hr of the reaction was ca. 85% under the harsh condition of 10 vol.% H2O and 100 ppm SO2 at a high gaseous hourly space velocity (GHSV) of 400,000 hr-1. Physicochemical properties of the catalysts were characterized by various techniques. The results showed that the electrostatic adsorption, which riveted the Pt elements mainly on the exposed TiO2 of the support surface, reduced the dispersion of Pt NPs on EG and achieved the effective dispersion of Pt NPs, hence significantly improving CO oxidation activity over the Pt/10EG-TiO2-10 catalyst. The 10 wt.% EG doped in TiO2 caused the TiO2 support to form a more hydrophobic surface, which reduced the adsorption of H2O and SO2 on the catalyst, greatly inhibited deposition of the TiOSO4 and formation of the PtSO4 species as well as suppressed the oxidation of SO2, thus resulting in an improvement in the resistance to H2O and SO2 of the Pt/10EG-TiO2-10 catalyst.

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In patients with diabetes, chronic hyperglycemia impairs immune function at wound sites, increasing susceptibility to infections, prolonging inflammation, and delaying healing. This study aimed to develop wound dressings that control bacterial infections and accelerate healing. Phloretin (PHL), which has antibacterial and anti-inflammatory properties, was encapsulated with γ-cyclodextrin (γ-CD) to form a PHL@CD complex with enhanced bioavailability. This complex was incorporated into nanofiber wound dressings composed of polycaprolactone and natural silk protein. The resulting dressings exhibited favorable physical and chemical properties, including nutrient transport and gas exchange, which are essential for wound healing. The nanofiber membranes exhibited antibacterial activity against Staphylococcus aureus (90.31 ±â€¯4.41 % inhibition), with high antioxidant capacity (91.48 ±â€¯0.33 % ABTS scavenging) and blood compatibility. The membranes also promoted cell viability. Importantly, the nanofiber dressings accelerated wound healing in a diabetic mouse model by reducing the duration of inflammation. The novel nanofiber wound dressing can significantly improve the treatment of diabetic wounds.

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C-terminally phosphorylated TAR DNA-binding protein of 43 kDa (TDP-43) marks the proteinaceous inclusions that characterize a number of age-related neurodegenerative diseases, including amyotrophic lateral sclerosis, frontotemporal lobar degeneration and Alzheimer's disease. TDP-43 phosphorylation at S403/S404 and (especially) at S409/S410 is, in fact, accepted as a biomarker of proteinopathy. These residues are located within the low complexity domain (LCD), which also drives the protein's liquid-liquid phase separation (LLPS). The impact of phosphorylation at these LCD sites on phase separation of the protein is a topic of great interest, as these post-translational modifications and LLPS are both implicated in proteinopathies. Here, we employed a combination of experimental and simulation-based approaches to explore this question on a phosphomimetic model of the TDP-43 LCD. Our turbidity and fluorescence microscopy data show that phosphomimetic Ser-to-Asp substitutions at residues S403, S404, S409 and S410 alter the LLPS behavior of TDP-43 LCD. In particular, unlike the LLPS of unmodified protein, LLPS of the phosphomimetic variants displays a biphasic dependence on salt concentration. Through coarse-grained modeling, we find that this biphasic salt dependence is derived from an altered mechanism of phase separation, in which LLPS-driving short-range intermolecular hydrophobic interactions are modulated by long-range attractive electrostatic interactions. Overall, this in vitro and in silico study provides a physiochemical foundation for understanding the impact of pathologically relevant C-terminal phosphorylation on the LLPS of TDP-43 in a more complex cellular environment.

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Despite the many mechanisms it has created to prevent unfolding and aggregation of proteins, many diseases are caused by abnormal folding of proteins, which are called misfolding diseases. During this process, proteins undergo structural changes and become stable, insoluble beta-sheet aggregates called amyloid fibrils. Mutations/disruptions in metal ion homeostasis in the ALS-associated metalloenzyme superoxide dismutase (SOD1) reduce conformational stability, consistent with the protein aggregation hypothesis for neurodegenerative diseases. However, the exact mechanism of involvement is not well understood. Hence, to understand the role of mutation/ metal deficiency in SOD1 misfolding and aggregation, we investigated the effects of apo/holo SOD1 variants on structural properties using biophysical/experimental techniques. The MD results support the idea that the mutation/metal deficiency can lead to a change in conformation. The increased content of ß-sheet structures in apo/holo SOD1 variants can be attributed to the aggregation tendency, which was confirmed by FTIR spectroscopy and dictionary of secondary structure in proteins (DSSP) results. Thermodynamic studies of GdnHCl showed that metal deficiency/mutation/intramolecular S-S reduction together are required to initiate misfolding/aggregation of SOD1. The results showed that apo/holo SOD1 variants under destabilizing conditions induced amyloid aggregates at physiological pH, which were detected by ThT/ANS fluorescence, as well as further confirmation of amyloid/amorphous species by TEM. This study confirms that mutations in the electrostatic loop of SOD1 lead to structural abnormalities, including changes in hydrophobicity, reduced disulfide bonds, and an increased propensity for protein denaturation. This process facilitates the formation of amyloid/amorphous aggregates ALS-associated.

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Aqueous Zn-ion batteries (ZIBs) have attracted attention for grid applications due to their cost-effectiveness and high security. However, their lifespan decreases at high temperatures due to declining interfacial stability and increased side reactions. To address these challenges, a ternary deep eutectic solvent-based flexible electrolyte, comprised of ZnClO4·6H2O, butanedinitrile (BD), and LiCl in an amphoteric polymer matrix, was developed to enable wide-temperature ZIBs working from -20 °C to 70 °C. The interactions among BD, Li+, and zinc hydrate alongside the amphoteric groups on the polyelectrolyte matrix could effectively suppress the interfacial side reactions and Zn dendrites formation. Consequently, the symmetric Zn cell demonstrates exceptional stability across a wide-temperature range, with the ability to survive up to 2780 hours (1 mA·cm-2) at 50 °C. Furthermore, the flexible Zn||PANI battery can operate stably over 1000 cycles at 50 °C, boasting an initial specific capacity of 124.8 mAh·g-1 and capacity retention rate of 87.9% (3 A·g-1). This work presents an effective strategy for designing high-stability energy storage devices with excellent security features that can function reliably across diverse temperature conditions.

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The efficient capture of low-pressure CO2 remains a significant challenge due to the lack of established multi-complexation of CO2 to active sites in microporous materials. In this study, we introduce a novel concept of reversible multi-complexation of CO2 to alkaline earth metal (AEM) ion pairs, utilizing a host site in ferrierite-type zeolite (FER). This unique site constrains two AEM ions in proximity, thereby enhancing and isotopically spreading their electrostatic potentials within the zeolite cavity. This electrostatic potential-engineered micropore can trap up to four CO2 molecules, forming M2+-(CO2)n-M2+ (n = 0-4, M = Ca, Sr, Ba) complexes, where each CO2 molecule is stabilized by interactions between terminal oxygen (Ot) in CO2 and the AEM ions. Notably, the Ba2+ pair site exhibits higher thermodynamic stability for multiple adsorptions due to the optimal binding mode of Ba2+-Ot-Ba2+. Through high-accuracy energy calculations, we established the relationship among structure, CO2 uptake, and operating temperature/pressure, demonstrating that the Ba2+ pair site can reversibly capture four CO2 molecules even at concentrations as low as 400 ppm and at 298 K. The findings in the present study provide a new direction for developing efficient CO2 adsorbents.

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Polyurethane materials have good biocompatibility, blood compatibility, mechanical properties, fatigue resistance and processability, and have always been highly valued as medical materials. Polyurethane fibers prepared by electrostatic spinning technology can better mimic the structure of natural extracellular matrices (ECMs), and seed cells can adhere and proliferate better to meet the requirements of tissue repair and reconstruction. The purpose of this review is to present the research progress of electrostatically spun polyurethane fibers in bone tissue engineering, skin tissue engineering, neural tissue engineering, vascular tissue engineering and cardiac tissue engineering, so that researchers can understand the practical applications of electrostatically spun polyurethane fibers in tissue engineering and regenerative medicine.

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In this report, we describe the incorporation of single-walled carbon nanotubes (CNTs) into 3D printable siloxane elastomers for electrostatic dissipation. The composite was characterized, focusing on how rheological and mechanical properties of the siloxane are affected at various CNT loading levels. Electrical properties were also characterized to develop materials with effective electrostatic dissipation. We demonstrate that low loadings (<1 wt %) of CNTs can be sufficiently dispersed into silicone resins that can be 3D printed, and the resulting material shows a significant improvement in electrostatic dissipation through the reduction in electrical resistivity with minimal effect on its mechanical properties.

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CONTEXT: In this work, in order to find new strategy to solve the safe problem of one famous high energy compound 1,3,5-trinitro-1,3,5-triazinane (RDX) under the impact and static electricity environment, cyclo[n]carbons (n = 10, C10; n = 14, C14; n = 18, C18) were employed to construct novel energetic composites (RDX@C10, RDX@C14, RDX@C18) with RDX for the first time. The investigated results showed that C10, C14 and C18 all can form stable composites with RDX through a exothermal process. Three cyclo[n]carbons could not only decrease the impact sensitivity of RDX by decreasing the positive ESP values and transferring the HPV region. But also could reduce the electrostatic sensitivity greatly by decreasing the energy gap, increasing the EHOMO and controlling the active electron-induced process and reaction. Among them, the desensitization effect by C18 and C14 was found to be much better than C10. In addition, three cyclo[n]carbons may be used as new sensors for the detection of RDX, due to the fast recovery time under different lights, and great change in the UV-Vis spectrum. These improvements may provide valuable insights for enhancing the safe performance of high energy compounds with similar structures to RDX, and broaden the application sphere of cyclo[n]carbons. METHODS: All of the calculations on the structures were carried out by using the Gaussian 09 software at the M06-2X/6-311G(d,p) level. In addition, further calculations on the properties and interactions were performed by using the Multiwfn software.

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Large-scale application of low-cost, high-safety and environment-compatible aqueous Zn metal batteries (ZMBs) is hindered by Zn dendrite failure and side reactions. Herein, highly reversible ZMBs are obtained by addition of trace D-pantothenate calcium additives to engineer a dual-functional interfacial layer, which is enabled by a bioinspired gating effect for excluding competitive free water near Zn surface due to the trapping and immobilization of water by hydroxyl groups, and guiding target Zn2+ transport across interface through carboxyl groups of pantothenate anions, as well as a dynamic electrostatic shielding effect around Zn protuberances from Ca2+ cations to ensure uniform Zn2+ deposition. In consequence, interfacial side reactions are perfectly inhibited owing to reduced water molecules reaching Zn surface, and the uniform and compact deposition of Zn2+ is achieved due to promoted Zn2+ transport and deposition kinetics. The ultra-stable symmetric cells with beyond 9000 h at 0.5 mA cm-2 with 0.5 mAh cm-2 and over 5000 h at 5 mA cm-2 with 1 mAh cm-2, and an average Coulombic efficiency of 99.8% at 1 mA cm-2 with 1 mAh cm-2, are amazingly realized. The regulated-electrolyte demonstrates high compatibility with verified cathodes for stable full cells. This work opens a brand-new pathway to regulate Zn/electrolyte interface to promise reversible ZMBs.

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The treatment of internal hemorrhage remains challenging due to the current limited antibacterial capability, hemostatic efficacy, and biocompatibility of hemostatic materials. The TEMPO-oxidized cellulose nanofibers/collagen/chitosan (TCNF/COL/CS) hemostatic aerogel was developed in this work by physically encasing COL in a sandwich structure and electrostatically self-assembling polyanionic TCNF with polycationic CS. In vitro coagulation experiments revealed the favorable procoagulant properties of TCNF/COL/CS along with high adhesion to erythrocytes and platelets. TCNF/COL/CS significantly increased the hemostatic efficacy by 59.8 % and decreased blood loss by 62.2 % in the liver injury model when compared to Surgicel®, the most frequently used hemostatic material. Furthermore, it demonstrated outstanding biodegradability both in vitro and in vivo, and a substantial increase in resistance (96.8 % against E. coli and 95.4 % against S. aureus) compared to TCNF. The significant hemostatic and biodegradable characteristics of TCNF/COL/CS can be ascribed to its interconnected porous structure, increased porosity, and efficient water absorption, along with the synergistic effect of the three constituents. The TCNF/COL/CS aerogel shows significant potential to control internal bleeding. A novel plant-derived nanocellulose composite aerogel has been described here for the first time; it has outstanding antibacterial characteristics, higher biocompatibility, and outstanding hemostatic characteristics in vivo.

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Solvent additives with a high boiling point (BP) and low vapor pressure (VP) have formed a key handle for improving the performance of organic solar cells (OSCs). However, it is not always clear whether they remain in the active-layer film after deposition, which can negatively affect the reproducibility and stability of OSCs. In this study, an easily removable solvent additive (4-chloro-2-fluoroiodobenzene (CFIB)) with a low BP and high VP is introduced, behaving like volatile solid additives that can be completely removed during the device fabrication process. In-depth studies of CFIB addition into the D18-Cl donor and N3 acceptor validate its dominant non-covalent intermolecular interactions with N3 through effective electrostatic interactions. Such phenomena improve charge dynamics and kinetics by optimizing the morphology, leading to enhanced performance of D18-Cl:N3-based devices with a power conversion efficiency of 18.54%. The CFIB-treated device exhibits exceptional thermal stability (T80 lifetime = 120 h) at 85 °C compared with the CFIB-free device, because of its morphological robustness by evolving no residual CFIB in the film. The CFIB features a combination of advantages of solvent (easy application) and solid (high volatility) additives, demonstrating its great potential use in the commercial mass production of OSCs.

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Electrostatic precipitators (ESPs) may enable high particle collection efficiency with minimal pressure drop in HVAC systems. However, studies of pathogen collection and inactivation in ESPs at medium to higher flow rates are limited. Here, a single-stage, wire-plate ESP operated at flow rates of 51 and 85 m3 h-1 was used to study the removal of virus-laden aerosol particles for three different airborne viruses: (1) bovine coronavirus (BCoV), (2) influenza A virus (IAV), and (3) porcine reproductive and respiratory virus (PRRSV). Size-resolved measurements of collection efficiency were obtained using Andersen cascade impactors (ACI) sampling upstream and downstream of the ESP. All measurements were analyzed based on three distinctive but complementary methods: (1) fluorimetry to assess physical collection, (2) RT-qPCR to assess viral RNA concentrations and (3) virus titration to assess virus viability. In general, log reductions by virus titration were highest followed by those from RT-qPCR, and last fluorimetry, suggesting that a portion of virus may be potentially inactivated in flight in the ESP. An effective migration (deposition) velocity ranging from 3.10 to 10.05 cm s-1 was also determined using the spatially resolved measurements of virus collection on the ESP plates.

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Two addition orders, i.e., the layer-by-layer (L) and mixed biopolymer (M) orders, were used to generate sodium caseinate - sugar beet pectin electrostatically stabilized o/w emulsions with 0.5% oil and varying sodium caseinate: sugar beet pectin ratios (3:1-1:3) at pH 4.5. Emulsion stability against environmental stresses (i.e., pH, salt addition, thermal treatment, storage and in vitro simulated gastrointestinal digestion) and its astaxanthin encapsulation against degradation during storage and in vitro digestion were evaluated. Results indicated that a total biopolymer concentration of 0.5% was optimal, with the preferred sodium caseinate-sugar beet pectin ratios for L and M emulsions being 1:1 and 1:3, respectively. L emulsions generally exhibited smaller droplet diameters than M emulsions across all ratios, except at 1:3. Lowering the pH to 1.5 substantially reduced the net negative charge of all emulsions, with only L emulsions precipitating at pH 3. M emulsions showed greater tolerance to salt addition, remaining stable up to 500 mM sodium and calcium concentrations, whereas L emulsions destabilized at levels exceeding 50 mM and 30 mM, respectively. All emulsions were stable when heated at 37 °C or 90 °C for 30 min. Astaxanthin degradation rates increased with prolonged storage, reaching 61.66% and 54.08% by day 7 for L and M emulsions, respectively. Encapsulation efficiency of astaxanthin in freshly prepared M emulsions (86.85%) was significantly higher compared to L emulsions (72.82%). M emulsions had 30% and 25% higher encapsulation efficiency of astaxanthin than L emulsions after in vitro digestion for 120 min and 240 min respectively. This study offers suggestions for interface design and process optimization to improve the performance of protein-polysaccharide emulsion systems, such as in beverages and dairy products, as well as their delivery effect of bioactives.

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This study presented a dual-layer freshness indicator film produced through electrospinning, combining cellulose acetate and polyvinylidene fluoride with zeolitic imidazolate framework-8 (ZIF-8) loaded with curcumin as the indicator. Our findings demonstrated that ZIF-8 effectively preserved its metal-organic framework structure during curcumin loading, ensuring the inherent color-changing ability of curcumin. The resulting colorimetric film exhibited altered tensile properties and increased water vapor permeability. Improved light stability and storage performance were observed. Compared to single-layer films, the dual-layer structure improved the hydrophilicity and stability of the indicator film. Importantly, the introduced indicator label efficiently captured the dynamic changes of TVB-N during freshness monitoring, providing comprehensive visual information for assessing fish freshness. The synergistic properties of ZIF-8, curcumin, and the dual-layer film structure contributed to an advanced freshness indicator system, providing a multifunctional and effective approach for real-time freshness assessment of fish freshness.

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HYPOTHESIS: Electrostatic interactions between colloids are governed by the overlap of their electric double layers (EDLs) and the ionic screening of the structural charges distributed at their core surface and/or in their peripheral ion-permeable shell, relevant to soft particles like polymer colloids and microorganisms. Whereas ion size-mediated effects on the organization of isolated EDLs have been analysed, their contribution to the electrostatic energy of interacting soft particles has received less attention THEORY AND SIMULATIONS: Herein, we elaborate a formalism to evaluate the electrostatic interaction energy profile between spherical core/shell particles, building upon a recent Poisson-Boltzmann theory corrected for the sizes of ions and particle structural charges, for ion correlations and dielectric decrement. Interaction energy is derived from pairwise disjoining pressure and exact Surface Element Integration method, beyond the Derjaguin approximation. The theory is sufficiently flexible to tackle homo- and hetero-interactions that involve weakly to highly charged hard, porous or core/shell nano- to micro-sized particles in asymmetric multivalent electrolytes. FINDINGS: Results illustrate how ion steric effects, ion correlations and dielectric decrement impact the sign, magnitude and range of the interactions depending on the particle size, the Debye length, and the geometric and electrostatic properties of the particle core and shell components.

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BACKGROUND: Food-grade Pickering particles, particularly plant proteins, have attracted significant interest due to their bio-based nature, environmental friendliness, and edibility. Mulberry-leaf protein (MLP) is a high-quality protein with rich nutritional value and important functional properties. It has special amphoteric and emulsifying characteristics, making it valuable for use in Pickering emulsions. This study aimed to investigate the feasibility of using MLP nanoparticles as solid particles to stabilize Pickering emulsions. RESULTS: The particle size of MLP nanoparticles was less than 300 nm under neutral and alkaline conditions. At pH 9, the zeta potential value reached -34.3 mV, indicating the electrostatic stability of the particles. As ion concentration increased, the particle size of MLP nanoparticles increased, and the zeta potential decreased. Throughout the storage process, no obvious aggregation or precipitation was observed in the dispersion of MLP nanoparticles, indicating strong stability. The particle size of the Pickering emulsion decreased with the increase in protein concentration. When the protein concentration was low, the particles on the oil-water interface became sparse, resulting in poor stability of the prepared emulsion and making it susceptible to aggregation and thus larger particle sizes. Increasing the oil-phase ratio to 70% (v/v) promotes the formation of Pickering emulsions, which exhibit exceptional stability when MLP nanoparticles are fixed at a concentration of 20 mg mL-1. CONCLUSION: The overall findings indicated that MLP nanoparticles have potential as food-grade materials for Pickering emulsions, marking a novel application of these nanoparticles in the food industry. © 2024 Society of Chemical Industry.

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In recent years, a wide variety of high-performance and versatile nanofiber membranes have been successfully created using different electrospinning methods. As vehicles for medication, they have been receiving more attention because of their exceptional antibacterial characteristics and ability to heal wounds, resulting in improved drug delivery and release. This quality makes them an appealing choice for treating various skin conditions like wounds, fungal infections, skin discoloration disorders, dermatitis, and skin cancer. This article offers comprehensive information on the electrospinning procedure, the categorization of nanofiber membranes, and their use in dermatology. Additionally, it delves into successful case studies, showcasing the utilization of nanofiber membranes in the field of skin diseases to promote their substantial advancement.

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Breathing and urination, are vital physiological activities of the human body, continuous real-time monitoring of these physiological behaviors could offer timely feedback on an individual's health status. However, current monitoring techniques predominantly rely on cumbersome and intricate medical apparatuses, posing challenges in adapting to the diverse requirements of multi-scenario detection. Consequently, there is a growing interest in developing wearable devices capable of monitoring breathing and urination. In this work, we developed a multifunctional sensor integrating humidity and pressure sensing modes using a simple dip-coating process. By introducing sodium carboxymethyl cellulose and conductive polyaniline hybrid intercalation between MXene layers, a stable conductive network is established through hydrogen bonds and electrostatic interactions among materials. The overall electromechanical properties of the composites will be well improved. And, the effects of different conductive filler ratios and the number of dipping times on the construction of conductive networks are investigated. The multifunctional sensor exhibited improved sensing characteristics, including detecting pressures up to 532 kPa and a sensitivity of 19.58 kPa-1. Furthermore, it also demonstrates good humidity-sensing capabilities. Tests on volunteers demonstrated the potential in the detection of breathing and urination. In addition, the sensors are capable of transmitting Morse code. This interesting application will offer the possibility of normal communication for people with speech impairments. Given its utility and sustainability, the sensor has potential for applications in wearable health monitoring, intelligent life and telemedicine.

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Removal of polar impurities, such as phospholipids, free fatty acids (FFA), and peroxides, can be challenging during the refining of crude canola oil. Current conventional refining methods are energy-intensive (e.g., hot water washes) and can generate significant waste (e.g., wastewater effluent) and neutral oil loss. This study investigated the joint use of nano-adsorbents and electrostatic field (E-field) treatment as a potential and sustainable alternative in removing these impurities during the oil refining process. Specifically, aluminum oxide (Al2O3) nanoparticles were employed to neutralize FFAs, achieving a 62.4% reduction in acid value while preserving the fatty acid profile of the oil. After refining, E-field treatment was successful in removing the spent nano-adsorbent from solution (up to 72.3% by weight), demonstrating enhanced efficiency compared to conventional methods (e.g., gravitational settling, filtration, and centrifugation). The neutral oil loss using Al2O3 nano-adsorbents was also comparable to conventional refining methods, with a 4.38% (by weight) loss. After E-field treatment, the Al2O3 nano-adsorbent was then calcined to assess reusability. The Al2O3 nano-adsorbent was effectively recycled for three refining cycles. the methods do not use of large amounts of water and generate minimal waste byproducts (e.g., effluent). Nonetheless, while the nano-adsorbents demonstrated promising results in FFA removal, they were less effective in eliminating peroxides and pigments. E-field techniques were also effective in removing spent nano-adsorbent; although, optimization of E-field parameters could further improve its binding capacity. Finally, future studies could potentially focus on the physicochemical modifications of the nano-adsorbent material to enhance their refining capacity and reusability. Overall, this study presents a sustainable alternative or addition to conventional refining methods and lays the groundwork for future research.