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Polyethylene oxide (PEO)-based all solid-state lithium metal batteries (ASSLMBs) are strongly hindered by the fast dendrite growth at the Li metal/electrolyte interface, especially under large rates. The above issue stems from the suboptimal interfacial chemistry and poor Li+ transport kinetics during cycling. Herein, a SnF2-catalyzed lithiophilic-lithiophobic gradient solid electrolyte interphase (SCG-SEI) of LixSny/LiF-Li2O is in-situ formed. The superior ionic LiF-Li2O rich upper layer (17.1 nm) possesses high interfacial energy and fast Li+ diffusion channels, wherein lithiophilic LixSny alloy layer (8.4 nm) could highly reduce the nucleation overpotential with lower diffusion barrier and promote rapid electron transportation for reversible Li+ plating/stripping. Simultaneously, the insoluble SnF2-coordinated PEO promotes the rapid Li+ ion transport in the bulk phase. As a result, an over 46.7 and 3.5 times improvements for lifespan and critical current density of symmetrical cells are achieved, respectively. Furthermore, LiFePO4-based ASSLMBs deliver a recorded cycling performance at 5 C (over 1000 cycles with a capacity retention of 80.0%). More importantly, impressive electrochemical performances and safety tests with LiNi0.8Mn0.1Co0.1O2 and pouch cell with LiFePO4, even under extreme conditions (i.e., 100 â), are also demonstrated, reconfirmed the importance of lithiophilic-lithiophobic gradient interfacial chemistry in the design of high-rate ASSLMBs for safety applications.
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Replacing the flammable liquid electrolytes with solid ones has been considered to be the most effective way to improve the safety of the lithium batteries. However, the solid electrolytes often suffer from low ionic conductivity and poor rate capability due to their relatively stable molecular/atomic architectures. In this study, we report a composite solid electrolyte, in which polyethylene oxide (PEO) is the matrix and Li6.4La3Zr1.45Ta0.5Mo0.05O12 (LLZTMO) and Li6.4La3Zr1.4Ta0.6O12 (LLZTO) are the fillers. Ta/Mo co-doping can further promote the ion transport capacity in the electrolyte. The synthesized composite electrolytes exhibit high thermal stability (up to 413 °C) and good ionic conductivity (LLZTMO-PEO 2.00 × 10-4 S·cm-1, LLZTO-PEO 1.53 × 10-4 S·cm-1) at 35 °C. Compared with a pure PEO electrolyte, whose ionic conductivity is in the range of 10-7~10-6 S·cm-1, the ionic conductivity of composite solid electrolytes is greatly improved. The full cell assembled with LiFePO4 as the positive electrode exhibits excellent rate performance and good cycling stability, indicating that prepared solid electrolytes have great potential applications in lithium batteries.
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Hot-melt extrusion (HME) potentially coupled with 3D printing is a promising technique for the manufacturing of dosage forms such as drug-eluting implants which might even be individually adapted to patient-specific anatomy. However, these manufacturing methods involve the risk of thermal degradation of incorporated drugs during processing. In this work, the stability of the anti-inflammatory drug dexamethasone (DEX) was studied during HME using the polymers Eudragit® RS, ethyl cellulose and polyethylene oxide. The extrusion process was performed at different temperatures. Furthermore, the influence of accelerated screw speed, the addition of the plasticizers triethyl citrate and polyethylene glycol 6000 or the addition of the antioxidants butylated hydroxytoluene and tocopherol in two concentrations were studied. The DEX recovery was analyzed by a high performance liquid chromatography method suitable for the detection of thermal degradation products. The strongest impact on the drug stability was found for the processing temperature, which was found to reduce the DEX recovery to <20% for certain processing conditions. In addition, differences between tested polymers were observed, whereas the use of additives did not result in remarkable changes in drug stability. In conclusion, suitable extrusion parameters were identified for the processing of DEX with high drug recovery rates for the tested polymers. Moreover, the importance of a suitable analysis method for drug stability during HME that is influenced by several parameters was highlighted.
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Electrospun drug-eluting fibers have demonstrated potentials in topical drug delivery applications, where drug releases can be modulated by polymer fiber compositions. In this study, blend fibers of polycaprolactone (PCL) and polyethylene oxide (PEO) at various compositions were electrospun from 10 wt% of polymer solutions to encapsulate a model drug of ibuprofen (IBP). The results showed that the average polymer solution viscosities determined the electrospinning parameters and the resulting average fiber diameters. Increasing PEO contents in the blend PCL/PEO fibers decreased the average elastic moduli, the average tensile strength, and the average fracture strains, where IBP exhibited a plasticizing effect in the blend PCL/PEO fibers. Increasing PEO contents in the blend PCL/PEO fibers promoted the surface wettability of the fibers. The in vitro release of IBP suggested a transition from a gradual release to a fast release when increasing PEO contents in the blend PCL/PEO fibers up to 120 min. The in vitro viability of blend PCL/PEO fibers using MTT assays showed that the fibers were compatible with MEF-3T3 fibroblasts. In conclusion, our results explained the scientific correlations between the solution properties and the physicomechanical properties of electrospun fibers. These blend PCL/PEO fibers, having the ability to modulate IBP release, are suitable for topical drug delivery applications.
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A major problem after tendon injury is adhesion formation to the surrounding tissue leading to a limited range of motion. A viable strategy to reduce adhesion extent is the use of physical barriers that limit the contact between the tendon and the adjacent tissue. The purpose of this study was to fabricate an electrospun bilayered tube of hyaluronic acid/polyethylene oxide (HA/PEO) and biodegradable DegraPol® (DP) to improve the anti-adhesive effect of the implant in a rabbit Achilles tendon full laceration model compared to a pure DP tube. Additionally, the attachment of rabbit tenocytes on pure DP and HA/PEO containing scaffolds was tested and Scanning Electron Microscopy, Fourier-transform Infrared Spectroscopy, Differential Scanning Calorimetry, Water Contact Angle measurements, and testing of mechanical properties were used to characterize the scaffolds. In vivo assessment after three weeks showed that the implant containing a second HA/PEO layer significantly reduced adhesion extent reaching levels comparable to native tendons, compared with a pure DP implant that reduced adhesion formation only by 20 %. Tenocytes were able to attach to and migrate into every scaffold, but cell number was reduced over two weeks. Implants containing HA/PEO showed better mechanical properties than pure DP tubes and with the ability to entirely reduce adhesion extent makes this implant a promising candidate for clinical application in tendon repair.
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Ácido Hialurónico , Polietilenglicoles , Andamios del Tejido , Animales , Ácido Hialurónico/química , Ácido Hialurónico/farmacología , Conejos , Polietilenglicoles/química , Andamios del Tejido/química , Tenocitos/efectos de los fármacos , Tenocitos/metabolismo , Tendón Calcáneo/efectos de los fármacos , Traumatismos de los Tendones/terapia , Adhesión Celular/efectos de los fármacos , Adherencias Tisulares/prevención & control , Tendones/efectos de los fármacos , Ingeniería de Tejidos/métodos , Materiales Biocompatibles/química , Materiales Biocompatibles/farmacología , Poliésteres/química , PoliuretanosRESUMEN
Polyethylene glycol (PEG) is widely used as phase change materials (PCM) due to their versatile working temperature and high latent heat. However, the low molecular weight of PEG prevents from the formation of flexible microfibers, and the common leakage problem associated with solid-liquid PCM further hinders their applications in various fields. To address these challenges, polyethylene oxide (PEO) is incorporated as the supporting matrix for PEG, leading to a successful electrospinning of fibrous mats. Due to the similar chemical nature of both PEG and PEO, the blended composites show great compatibility and produce uniform electrospun fibers. The thermal properties of these fibers are characterized by DSC and TGA, and supercooling for the PEG(1050) component is effectively reduced by 75-85%. The morphology changes before and after leakage test are analyzed by SEM. Tensile and DMA tests show that the presence of PEG(1050) component contributes to plasticization effect, improving mechanical and thermomechanical strength. The ratio of PEO(600K):PEG(1050) at 7:3 affords the optimal performance with good chemical and form-stability, least shrinkage, and uniformity. These fibrous mats have potential applications in areas of food packaging, flexible wearable devices, or textiles to aid in thermal regulation.
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Low ionic conductivity and poor interface stability of poly(ethylene oxide) (PEO) restrict the practical application as polymeric electrolyte films to prepare solid-state lithium (Li) metal batteries. In this work, biomass-based carboxymethyl chitosan (CMCS) is designed and developed as organic fillers into PEO matrix to form composite electrolytes (PEO@CMCS). Carboxymethyl groups of CMCS fillers can promote the decomposition of Lithium bis(trifluoromethane sulfonimide) (LiTFSI) to generate more lithium fluoride (LiF) at CMCS/PEO interface, which not only forms ionic conductive network to promote the rapid transfer of Li+ but also effectively enhances the interface stability between polymeric electrolyte and Li metal. The enrichment of carboxyl, hydroxyl, and amidogen functional groups within CMCS fillers can form hydrogen bonds with ethylene oxide (EO) chains to improve the tensile properties of PEO-based electrolyte. In addition, the high hardness of CMCS additives can also strengthen mechanical properties of PEO-based electrolyte to resist penetration of Li dendrites. LiLi symmetric batteries can achieve stable cycle for 2500 h and lithium iron phosphate full batteries can maintain 135.5 mAh g-1 after 400 cycles. This work provides a strategy for the enhancement of ion conductivity and interface stability of PEO-based electrolyte, as well as realizes the resource utilization of biomass-based CMCS.
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Quitosano , Conductividad Eléctrica , Suministros de Energía Eléctrica , Electrólitos , Litio , Polietilenglicoles , Quitosano/química , Quitosano/análogos & derivados , Polietilenglicoles/química , Litio/química , Electrólitos/química , Iones/químicaRESUMEN
Octylphenol polyethoxylates (OPEOn) are composed of a hydrophobic octylphenol (OP) group and a hydrophilic polyethylene oxide (EO) chain and are widely used in commercial products. Shorter EO chains and OPEOn biometabolites have been identified as endocrine-disrupting contaminants and can threaten biotic factors in the ecosystem. In this study, OPEOn at three EO lengths (TX-45, TX-114, and TX-165) were selected in monomer (MN) or micelle (MC) state for batch experiments under aerobic conditions, with results showing biodegradation rates of 90 % within 35-70 h. The pseudo-first-order constant (k) of OPEOn biodegradation was observed in the order TX-45 (0.1414 h-1) > TX-114 (0.0556 h-1) > TX-165 (0.0485 h-1), with biomineralisation reaching at least 80 % for all OPEOn. The selective biodegradation of EO chains was also measured, with initial accumulation of OPEO3 observed along with the depletion of longer EO chains for TX-45 and TX-114 in both the MN and MC states. A similar trend was observed for the MN state of TX-165, with OPEO3-OPEO9 observed to accumulate and reduced after 70 h. MC biodegradation was accomplished via the initial accumulation of OPEO3-OPEO9. The amounts of OPEO3 increased and others reduced; however, OPEO3 remained high at the end of biodegradation for TX-165. Bacterial community analysis indicated that the genera Sphingobium spp., Pseudomonas spp., Flavobacterium spp., Comamonas spp., and Sphingopyxis spp. dominate OPEOn biodegradation, and they have their roles during biodegradation, and the community-level physiological profile (CLPP) was also changed by biodegradation in both the MN and MC states.
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Biodegradación Ambiental , Fenoles , Fenoles/metabolismo , Polietilenglicoles/metabolismo , Bacterias/metabolismo , Aerobiosis , Disruptores Endocrinos/metabolismoRESUMEN
Hydrophilic nanofibers offer promising potential for the delivery of drugs with diverse characteristics. Yet, the effects of different drugs incorporated into these nanofibers on their properties remain poorly understood. In this study, we systematically explored how model drugs, namely ibuprofen, carvedilol, paracetamol, and metformin (hydrochloride), affect hydrophilic nanofibers composed of polyethylene oxide and poloxamer 188 in a 1:1 weight ratio. Our findings reveal that the drug affects the conductivity and viscosity of the polymer solution for electrospinning, leading to distinct changes in the morphology of electrospun products. Specifically, drugs with low solubility in ethanol, the chosen solvent for polymer solution preparation, led to the formation of continuous nanofibers with uniform diameters. Additionally, the lower solubility of metformin in ethanol resulted in particle appearance on the nanofiber surface. Furthermore, the incorporation of more hydrophilic drugs increased the surface hydrophilicity of nanofiber mats. However, variations in the physicochemical properties of the drugs did not affect the drug loading and drug entrapment efficiency. Our research also shows that drug properties do not notably affect the immediate release of drugs from nanofibers, highlighting the dominant role of the hydrophilic polymers used. This study emphasizes the importance of considering specific drug properties, such as solubility, hydrophilicity, and compatibility with the solvent used for electrospinning, when designing hydrophilic nanofibers for drug delivery. Such considerations are crucial for optimizing the properties of the drug delivery system, which is essential for achieving therapeutic efficacy and safety.
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Significance: Assessing the nanostructure of polymer solutions and biofluids is broadly useful for understanding drug delivery and disease progression and for monitoring therapy. Aim: Our objective is to quantify bronchial mucus solids concentration (wt. %) during hypertonic saline (HTS) treatment in vitro via nanostructurally constrained diffusion of gold nanorods (GNRs) monitored by polarization-sensitive optical coherence tomography (PS-OCT). Approach: Using PS-OCT, we quantified GNR translational (DT) and rotational (DR) diffusion coefficients within polyethylene oxide solutions (0 to 3 wt. %) and human bronchial epithelial cell (hBEC) mucus (0 to 6.4 wt. %). Interpolation of DT and DR data is used to develop an assay to quantify mucus concentration. The assay is demonstrated on the mucus layer of an air-liquid interface hBEC culture during HTS treatment. Results: In polymer solutions and mucus, DT and DR monotonically decrease with increasing concentration. DR is more sensitive than DT to changes above 1.5 wt. % of mucus and exhibits less intrasample variability. Mucus on HTS-treated hBEC cultures exhibits dynamic mixing from cilia. A region of hard-packed mucus is revealed by DR measurements. Conclusions: The extended dynamic range afforded by simultaneous measurement of DT and DR of GNRs using PS-OCT enables resolving concentration of the bronchial mucus layer over a range from healthy to disease in depth and time during HTS treatment in vitro.
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Oro , Moco , Nanotubos , Tomografía de Coherencia Óptica , Tomografía de Coherencia Óptica/métodos , Humanos , Nanotubos/química , Oro/química , Moco/química , Moco/metabolismo , Difusión , Bronquios/diagnóstico por imagen , Células Epiteliales/química , Células Epiteliales/metabolismo , Solución Salina Hipertónica/farmacología , Solución Salina Hipertónica/química , Células CultivadasRESUMEN
A heterograft copolymer with an alginate backbone, hetero-grafted by polymer pendant chains displaying different lower critical solution temperatures (LCSTs), combined with a pH-responsive poly(2-vinyl pyridine)-b-poly(ethylene oxide) (P2VP-b-PEO) diblock copolymer forming micellar nanoparticles, was investigated in aqueous media at various pHs. Due to its thermo-responsive side chains, the copolymer forms hydrogels with a thermo-induced sol-gel transition, above a critical temperature, Tgel (thermo-thickening). However, by lowering the pH of the medium in an acidic regime, a remarkable increase in the elasticity of the formulation was observed. This effect was more pronounced in low temperatures (below Tgel), suggesting secondary physical crosslinking, which induces significant changes in the hydrogel thermo-responsiveness, transforming the sol-gel transition to soft gel-strong gel. Moreover, the onset of thermo-thickening shifted to lower temperatures followed by the broadening of the transition zone, implying intermolecular interactions between the uncharged alginate backbone with the PNIPAM side chains, likely through H-bonding. The shear-thinning behavior of the soft gel in low temperatures provides injectability, which allows potential applications for 3D printing. Furthermore, the heterograft copolymer/nanoparticles composite hydrogel, encapsulating a model hydrophobic drug in the hydrophobic cores of the nanoparticles, was evaluated as a pH-responsive drug delivery system. The presented tunable drug delivery system might be useful for biomedical potential applications.
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The pharmaceutical industry usually utilizes either hydrophobic or hydrophilic substances extracted from raw plant materials to prepare a final product. However, the waste products from the plant material still contain biologically active components with the opposite solubility. The aim of this study was to enhance the comprehensive usability of plant materials by developing a new no-waste extraction method for eucalypt leaves and by investigating the phytochemical and pharmacological properties of eucalypt extracts and their 3D-printed dosage forms. The present extraction method enabled us to prepare both hydrophobic soft extracts and hydrophilic (aqueous) dry extracts. We identified a total of 28 terpenes in the hydrophobic soft extract. In the hydrophilic dry extract, a total of 57 substances were identified, and 26 of them were successfully isolated. The eucalypt extracts studied showed significant antimicrobial activity against Staphylococcus aureus, Pseudomonas aeruginosa, Bacillus subtilis, Candida albicans, Corynebacterium diphtheriae gravis, and Corynebacterium diphtheriae mitis. The anti-inflammatory activity of the dry extract was studied using a formalin-induced-edema model in mice. The maximum anti-exudative effect of the dry extract was 61.5% at a dose of 20 mg/kg. Composite gels of polyethylene oxide (PEO) and eucalypt extract were developed, and the key process parameters for semi-solid extrusion (SSE) 3D printing of such gels were verified. The SSE 3D-printed preparations of novel synergistically acting eucalypt extracts could have uses in antimicrobial and anti-inflammatory medicinal applications.
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Objective: Today, designing nanofibers with antibacterial properties using electrospinning technology is one of the attractive approaches for wound healing. Methods: & analysis: This study aims to fabricate a nanocomposite from polyethylene oxide (PEO) coated with copper nanoparticles (NPs) and defensin peptide with wound healing and antimicrobial properties in different ratios of CuNPs/defensin (2/0 mg), (1.5/0.5 mg), and (1/1 mg) in the fixed contain polymer (98 mg). Then, the nanofiber properties were investigated by SEM, tensile, DSC, and BET analysis. Also, the antibacterial properties against S. aureus and E. coli, antioxidant, and in-vivo wound healing effects and histological analysis of the designed nanocomposites were evaluated in rat models. Results: Our SEM images showed that CuNPs and defensin were properly coated on the PEO surface. According to the tensile, DSC, and antibacterial analysis results, the most appropriate feature was related to CuNPs/defensin (1.5/0.5 mg), with maximum elasticity, heat resistance, and antibacterial activity. Furthermore, the designed nanocomposites showed the best performance as a wound closure agent by increasing dermis and epidermis volume density, stimulating fibroblast cells and collagen fiber production, and improving skin vessels. Conclusion: According to our results, PEO nanofibers loaded with CuNPs and defensin have the best potential for wound healing, and they can be used as antibacterial materials in the textile, drug, and medical industries.
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Due to its outstanding qualities, particularly when it takes the shape of hydrogels, chitosan is a well-known biological macromolecule with many applications. When chitosan hydrogels are modified with other polymers, the desirable function as skin regeneration hydrogels is compromised; nevertheless, the mechanical properties can be improved, which is crucial for commercialization. In this study, for the first time, bimetallic zinc silver metal-organic frameworks (ZAg MOF) loaded with ascorbic acid were added to chitosan/polyethylene oxide (PEO) based interpenetrating polymer network (IPN) hydrogels that were crosslinked with biotin to improve their antimicrobial activity, mechanical characteristics, and sustainable treatment of wounds. Significant changes in the microstructure, hydrophilicity level, and mechanical properties were noticed. Ascorbic acid release patterns were upregulated in an acidic environment pH (5.5) that mimics the initial wound pH. Impressive cell viability (98 %), antimicrobial properties, and almost full skin healing in a short time were achieved for the non-replaceable chitosan/PEO developed hydrogels. Enhancing the wound healing of the treated animals using the prepared CS/PEO hydrogel dressing was found to be a result of the inhibition of dermal inflammation via decreasing IL-1ß, suppressing ECM degradation (MMP9), stimulating proliferation through upregulation of TGF-ß and increasing ECM synthesis as it elevates collagen 1 and α-SMA contents. The findings support the implementation of developed hydrogels as antimicrobial hydrogels dressing for fast skin regeneration.
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Quitosano , Animales , Quitosano/farmacología , Quitosano/química , Polietilenglicoles/farmacología , Antibacterianos/química , Hidrogeles/farmacología , Hidrogeles/química , Polímeros , Ácido AscórbicoRESUMEN
Silk fibroin (SF) has excellent biocompatibility and is one of the most commonly used polymer materials. However, SF fibers have serious drawbacks as antibacterial materials due to their lack of stability and bacterial resistance. Therefore, it is of paramount significance to enhance the stability and bolster the bacterial resistance of SF fibers. In this study, SF fibers were fabricated and loaded with Ag nanoparticles (AgNPs) to improve the antimicrobial properties of the fibers. The impact of reduction conditions on the size of AgNPs was also investigated. In an antibacterial test, the fibers that were prepared exhibited over 98% bacterial resistance against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli). Therefore, as an efficient antibacterial material, these fibers are expected to become a candidate material in medical and textile fields. This study offers a novel approach for the utilization of SF fibers in the realm of antibacterial applications.
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Solid state nanochannels provide significant practical advantages in many fields due to their interesting properties, such as controllable shape and size, robustness, ion selectivity. But their complex preparation processes severely limit their application. In this study, a simple cost-effective method to fabricate single nanochannel by embedding a single polyethylene oxide (PEO) nanofiber is presented. Firstly, PEO nanofibers are prepared by electrospinning, and then a single PEO nanofiber are precisely transferred to the target sample using a micromanipulation platform. Then, PDMS is used for embedding, and finally, the PEO nanofiber is dissolved to obtain a single nanochannel. Unlike other methods of preparing nanochannels by embedding nanofibers, this method can prepare single nanochannel. The diameter of nanochannel can be as fine as 100â nm, and the length can reach several micrometers. The power generation between two potassium chloride solutions with various combinations of concentrations was investigated using the nanochannel. This low-cost flexible nanochannel can also be used in various applications, including DNA sequencing and biomimetic ion channel.
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To combat opioid abuse, the U.S. Food and Drug Administration (FDA) released a comprehensive action plan to address opioid addiction, abuse, and overdose that included increasing the prevalence of abuse-deterrent formulations (ADFs) in opioid tablets. Polyethylene oxide (PEO) has been widely used as an excipient to deter abuse via nasal insufflation. However, changes in abuse patterns have led to unexpected shifts in abuse from the nasal route to intravenous injection. Case reports identify adverse effects similar to thrombotic thrombocytopenic purpura (TTP) syndrome following the intravenous (IV) abuse of opioids containing PEO excipient. Increased risk of IV opioid ADF abuse compared to clinical benefit of the drug led to the removal of one opioid product from the market in 2017. Because many generic drugs containing PEO are still in development, there is interest in assessing safety consistent with generic drug regulation and unintended uses. Currently, there are no guidelines or in vitro assessment tools to characterize the safety of PEO excipients taken via intravenous injection. To create a more robust excipient safety evaluation tool and to study the mechanistic basis of HMW PEO-induced TMA, a dynamic in vitro test system involving blood flow through a needle model has been developed.
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Analgésicos Opioides , Trastornos Relacionados con Opioides , Humanos , Polietilenglicoles/toxicidad , Polímeros , Peso Molecular , Excipientes , Técnicas In VitroRESUMEN
Introduction: Polymethyl methacrylate is a polymer commonly used in clinical dentistry, including denture bases, occlusal splints and orthodontic retainers. Methods: To augment the polymethyl methacrylate-based dental appliances in counteracting dental caries, we designed a polymer blend film composed of polymethyl methacrylate and polyethylene oxide by solution casting and added sodium fluoride. Results: Polyethylene oxide facilitated the dispersion of sodium fluoride, decreased the surface average roughness, and positively influenced the hydrophilicity of the films. The blend film made of polymethyl methacrylate, polyethylene oxide and NaF with a mass ratio of 10: 1: 0.3 showed sustained release of fluoride ions and acceptable cytotoxicity. Antibacterial activity of all the films to Streptococcus mutans was negligible. Discussion: This study demonstrated that the polymer blends of polyethylene oxide and polymethyl methacrylate could realize the relatively steady release of fluoride ions with high biocompatibility. This strategy has promising potential to endow dental appliances with anti-cariogenicity.
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Powdery hexagonal boron nitride (h-BN), as an important material for electrochemical energy storage, has been typically synthesized in bulk and one/two-dimensional (1/2D) nanostructured morphologies. However, until now, no method has been developed to synthesize powdery three-dimensional (3D) h-BN. This work introduces a novel NaCl-glucose-assisted strategy to synthesize micron-sized 3D h-BN with a honeycomb-like structure and its proposed formation mechanism. We propose that NaCl acts as the template of 3D structure and promotes the nitridation reaction by adsorbing NH3 . Glucose facilitates the homogeneous coating of boric acid onto the NaCl surface via functionalizing the NaCl surface. During the nitridation reaction, boron oxides (BO4 and BO3 ) form from a dehydration reaction of boric acid, which is then reduced to O2 -B-N and O-B-N2 intermediates before finally being reduced to BN3 by NH3 . When incorporated into polyethylene oxide-based electrolytes for Li metal batteries, 5â wt % of 3D h-BN significantly enhances ionic conductivity and mechanical strength. Consequently, this composite electrolyte demonstrates superior electrochemical stability. It delivers 300â h of stable cycles in the Li//Li cell at 0.1â mA cm-2 and retains 89 % of discharge capacity (138.9â mAh g-1 ) after 100 cycles at 1â C in the LFP//Li full cell.
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Wound dressings are crucial for wound healing. Ideal wound dressings should possess many functions such as wettability, antibacterial activity and anti-adherent property to promote wound healing. In the present study solution blown spinning (SBS) technology was applied to prepare chitosan/polyethylene oxide (CS/PEO) nanofiber dressings in high efficiency. The obtained nanofiber dressings were treated with anhydrous ethanol to improve the fiber structure and enhance the functionality of the fiber dressings. The results show that the treated nanofibers had higher crystallinities and higher CS contents. The CS/PEO nanofiber dressings fabricated by using no additives and crosslinking had excellent wettability, water stability and antibacterial activity against Escherichia coli and Staphylococcus aureus reached to over 99.99 %. In addition, the CS/PEO nanofiber dressings exhibited high breathability, antioxidant activity and anti-adhesion function. The in vivo animal experiment confirmed that the nanofiber dressings enhanced cell proliferation and significantly accelerated the wound healing within 10 days. The developed CS/PEO nanofiber dressings have great potential in the clinical field of wound healing.