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Wearable pressure sensors have attracted great interest due to their potential applications in healthcare monitoring and human-machine interaction. However, it is still a critical challenge to simultaneously achieve high sensitivity, low detection limit, fast response, and outstanding breathability for wearable electronics due to the difficulty in constructing microstructure on a porous substrate. Inspired by the spinosum microstructure of human skin for highly-sensitive tactile perception, a biomimetic flexible pressure sensor is designed and fabricated by assembling MXene-based sensing electrode and MXene-based interdigitated electrode. The product biomimetic sensor exhibits good flexibility and suitable air permeability (165.6 mm s-1), comparable to the typical air permeable garments. Benefiting from the two-stage amplification effect of the bionic intermittent structure, the product bionic sensor exhibits an ultrahigh sensitivity (1368.9 kPa-1), ultrafast response (20 ms), low detection limit (1 Pa), and high-linearity response (R2 = 0.997) across the entire sensing range. Moreover, the pressure sensor can detect a wide range of human motion in real-time through intimate skin contact, providing essential data for biomedical monitoring and personal medical diagnosis. This principle lays a foundation for the development of human skin-like high-sensitivity, fast-response tactile sensors.
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Pressão , Têxteis , Dispositivos Eletrônicos Vestíveis , Humanos , Pele , Eletrônica , EletrodosRESUMO
Electronic textiles (e-textiles) hold great promise for serving as next-generation wearable electronics owing to their inherent flexible, air-permeable, and lightweight characteristics. However, these e-textiles are of limited performance mainly because of lacking powerful materials combination. Herein, a versatile e-textile through a simple, high-efficiency mixed-dimensional assembly of 2D MXene nanosheets and 1D silver nanowires (AgNWs) are presented. The effective complementary actions of MXene and AgNWs endow the e-textiles with superior integrated performances including self-powered pressure sensing, ultrafast joule heating, and highly efficient electromagnetic interference (EMI) shielding. The textile-based self-powered smart sensor systems obtained through the screen-printed assembly of MXene-based supercapacitor and pressure sensor are flexible and lightweight, showing ultrahigh specific capacitance (2390 mF cm-2 ), robust areal energy density (119.5 µWh cm-2 ), excellent sensitivity (474.8 kPa-1 ), and low detection limit (1 Pa). Furthermore, the interconnected conductive MXene/AgNWs network enables the e-textile with ultrafast temperature response (10.4 °C s-1 ) and outstanding EMI shielding effectiveness of ≈66.4 dB. Therefore, the proposed mixed-dimensional assembly design creates a multifunctional e-textile that offers a practical paradigm for next-generation smart flexible electronics.
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In order to improve the photocatalytic performance of g-C3N4, the g-C3N4/Ti3C2/Ag3PO4 S-type heterojunction catalyst was prepared by electrostatic assembly method, and then the g-C3N4/Ti3C2/Ag3PO4/PAN composite nanofiber membrane was prepared by electrospinning technology. The morphology and chemical properties of the nanofiber membrane were characterized by SEM, FTIR, and XRD, and the photocatalytic degradation of tetracycline hydrochloride (TC) in water by the nanofiber membrane was investigated. The results showed that g-C3N4/Ti3C2/Ag3PO4 could be successfully loaded on PAN and uniformly distributed on the surface of composite nanofiber membrane by electrospinning technology. Increasing the amount of loading and catalyst, lowering the pH value and TC concentration of the system were conducive to the oxidation and degradation of TC. The nano-fiber catalytic membrane had been recycled five times and found to have excellent photocatalytic stability and reusability. The study of catalytic mechanism showed that h+, â¢OH and â¢O2- were produced and participated in the oxidation degradation reaction of TC, and â¢O2- plays a major role in catalysis. Therefore, this work provides a new insight into the construction of high-performance and high-stability photocatalytic system by electrospinning technology.
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Indocyanine green (ICG) is an important kind of near infrared (NIR) photosensitive molecules for PTT/PDT therapy as well as imaging. When exposed to NIR light, ICG can produce reactive oxygen species (ROS), which can kill cancer cells and pathogenic bacteria. Moreover, the absorbed light can also be converted into heat by ICG molecules to eliminate cancer cells. In addition, it performs exceptionally well in optical imaging-guided tumor therapy and antimicrobial therapy due to its deeper tissue penetration and low photobleaching properties in the near-infrared region compared to other dyes. In order to solve the problems of water and optical stability and multi-function problem of ICG molecules, composite nanomaterials based on ICG have been designed and widely used, especially in the fields of tumors and sterilization. So far, ICG molecules and their composite materials have become one of the most famous infrared sensitive materials. However, there have been no corresponding review articles focused on ICG molecules. In this review, the molecular structure and properties of ICG, composite material design, and near-infrared light- triggered anti-tumor, and antibacterial, and clinical applications are reviewed in detail, which of great significance for related research.
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Dermatite Fototóxica , Verde de Indocianina , Humanos , Verde de Indocianina/farmacologia , Corantes , Antibacterianos , Temperatura AltaRESUMO
Antibacterial fibers have great potential in many applications including wound dressings, surgical gowns, and surgical sutures, and play an important role in our daily life. However, the traditional fabrication method for the antibacterial fibers shows high cost, complexity, and inferior antibacterial durability. Herein, we report a facile and scalable fabrication of highly effective antibacterial alginate (SA) composite fibers through blend spinning of zeolitic imidazolate framework-67 (ZIF-67) particles and SA. The fabricated ZIF-67@SA composite fibers show high tensile strength and initial modulus. More importantly, the ZIF-67@SA composite fibers demonstrate excellent antibacterial properties, and the antibacterial efficiency reaches over 99% at ultralow ZIF-67 loading (0.05 wt%). In addition, the ZIF-67@SA fibers show good antibacterial durability even after five laundering cycles. The excellent antibacterial performance of the ZIF-67@SA fibers is attributed to the synergistic effects of the highly effective antibacterial ZIF-67 particles, swelling of alginate, and immobilization of ZIF-67 particles both inside and outside the fiber surface. This work may shed light on the antibacterial mechanism of metal organic frameworks and pave the way for the development of high-performance antibacterial textiles.
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Alginatos/química , Antibacterianos/química , Estruturas Metalorgânicas/química , Zeolitas/química , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Imidazóis/químicaRESUMO
Solar-driven photothermal conversion can produce clean water from dye wastewater while leaving the dye in the evaporation medium. Herein, a biomass-based composite hydrogel via down-fiber carbon (DFC) aerogel modified with chitosan-polyvinyl alcohol (CS-PVA) hydrogel was designed to address the aforementioned problem. The CS-PVA@DFC hydrogel integrated the capacity of simultaneous clean water production/dye adsorption during the day and continuous dye adsorption during the night. Furthermore, the modification of the CS-PVA hydrogel endowed the composite hydrogel with enhanced compression stress of 190.07 kPa (76.03 times that of DFC aerogel of 2.50 kPa) and impressive resilient recovery. Moreover, the CS-PVA@DFC hydrogel possessed solar light absorption of 99.56 % and strengthened water replenishment capacity due to the high porosity and CS-PVA hydrophilic network structure. The CS-PVA@DFC hydrogel demonstrated a stable, high evaporation rate of 2.34 kg·m-2·h-1 and simultaneous dye adsorption capacity of 70.39 % for treating methyl orange dye solution within 5 h. Additionally, the 24-h outdoor test showed that the CS-PVA@DFC hydrogel possessed excellent clean water production capacity during the daytime (reaching 4.17 kg·m-2·h-1 at 1:00p.m.) and continuous satisfactory dye adsorption capacity all day (89.68 %). These findings will inspire researchers seeking opportunities to improve the mechanical properties of aerogel and its application for treating wastewater, especially wastewater with harmful dyes.
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Ag cluster catalyst-based oxidation of CO to CO2 is an important way to remove CO at low temperatures. However, the instability of silver clusters seriously limits the catalytic application. Herein, sub-nanosized EMT zeolite nanoparticles served as Ag cluster carriers with high selectivity, low coordination, and unsaturated atom active sites. The silver clusters with sub-nanometer size can be controlled with different charge states and loading rates. A detection film with 500 nm was further prepared by assembling the Ag-EMT composites with a small amount of Nalco as an adhesive. For CO detection, a completely enclosed gas sensing device based on in situ infrared spectroscopy was employed without air interference. CO was accurately introduced into the detection chamber and catalysed into CO2 by silver loaded EMT zeolite films, and the whole process was accurately recorded by infrared spectroscopy. CO with a detection range of 2-50 ppm was realized, showing great application potential in gas monitoring.
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Poly-γ-glutamic acid (γ-PGA) is a natural polymer composed of glutamic acid monomer and it has garnered substantial attention in both the fields of material science and biomedicine. Its remarkable cell compatibility, degradability, and other advantageous characteristics have made it a vital component in the medical field. In this comprehensive review, we delve into the production methods, primary application forms, and medical applications of γ-PGA, drawing from numerous prior studies. Among the four production methods for PGA, microbial fermentation currently stands as the most widely employed. This method has seen various optimization strategies, which we summarize here. From drug delivery systems to tissue engineering and wound healing, γ-PGA's versatility and unique properties have facilitated its successful integration into diverse medical applications, underlining its potential to enhance healthcare outcomes. The objective of this review is to establish a foundational knowledge base for further research in this field.
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Aqueous ammonium-ion batteries have attracted intense interest lately as promising energy storage systems due to the price advantage and fast charge/discharge capability of ammonium-ion redox reactions. However, the research on the strength and energy storage characteristics of ammonium-ion fiber batteries is still limited. In this study, an ammonium-ion fiber battery with excellent mechanical strength, flexibility, high specific capacity, and long cycle-life has been developed with a robust honeycomb-like ammonium vanadate@carbon nanotube (NH4V4O10@CNT) cathode. The fiber electrode delivers a steady specific capacity of 241.06 mAh cm-3 at a current of 0.2 mA. Moreover, a fiber full cell consisting of an NH4V4O10@CNT cathode and a PANI@CNT anode exhibits a specific capacity of 7.27 mAh cm-3 at a current of 0.3 mA and retains a high capacity retention of 72.1% after 1000 cycles. Meanwhile, it shows good flexibility and superior electrochemical performance after 500 times bending or at different deformation states. This work offers a reference for long-cycle, flexible fibrous ammonium-ion batteries.
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Flexible, lightweight, and durable electromagnetic interference (EMI) shielding materials are urgently required to solve the increasingly serious electromagnetic radiation pollution. Transition metal carbides/nitrides (MXenes) are promising candidates for EMI shielding materials because of their excellent metallic electrical conductivity. However, MXenes are highly susceptible to oxidization when exposed to wet environments, leading to the loss of their functional properties and degradation of reliability and stability. Herein, an interfused core-shell heterogeneous reduced graphene oxide (rGO)/MXene aerogel (GMA) is designed for the first time via coaxial wet spinning and freeze-drying. The fabricated GMAs exhibit excellent EMI shielding performance, and the EMI shielding effectiveness (SE) and specific EMI SE can be up to 83.3 dB and 3119 dB·cm3/g, respectively, which is higher than most carbon-based and MXene-based aerogels and foams. More importantly, GMAs have only a 17.4 % degradation in EMI shielding performance after 120 days due to the protection of hydrophobic graphene sheath, exhibiting superior EMI shielding durability to its MXene film counterpart. Moreover, the hydrophobic GMAs exhibit good oil/water separation and thermal insulation performance. The interfused core-shell GMAs are highly promising for applications in durable EMI shielding, thermal insulation, oil/water separation and sensors, etc.
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Smart wearable electronics have drawn increasing attention for their potential applications in personal thermal management, human health monitoring, portable energy conversion/storage, electronic skin and so on. However, it is still a critical challenge to fabricate the multifunctional textiles with tunable morphology and performance while performing well in flexibility, air permeability, wearing comfortability. Herein, we develop a novel roll-to-roll layer-by-layer assembly strategy to construct bark-shaped carbon nanotube (CNT)/Ti3C2Tx MXene composite film on the fiber surface. The fabricated bark-shaped CNT/MXene decorated fabrics (CMFs) exhibit good flexibility, air permeability and electrical conductivity (sheet resistance, 6.6 Ω/â¡). In addition, the CMFs demonstrate good electrothermal performance (70.9 °C, 5 V), electromagnetic interference (EMI) shielding performance (EMI shielding effectiveness, 30.0 dB under X-Brand), and high sensitivity as the flexible piezoresistive sensors for monitoring the human motions. Importantly, our CMFs show distinctive EMI shielding mechanism, where a great proportion of incident electromagnetic microwaves are reflected by the bark-shaped CNT/MXene films owing to the multi-interface scattering effects. This work may provide a new strategy for the fabrication of multifunctional textile-based electronics and pave the way for smart wearable electronics.
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Nanotubos de Carbono , Dispositivos Eletrônicos Vestíveis , Eletrônica , Humanos , Casca de Planta , Têxteis , TitânioRESUMO
Multifunctional electronic textiles hold great potential applications in the wearable electronics field. However, it remains challenging to seamlessly integrate the multiple functions on the textile substrates without sacrificing their intrinsic properties. Herein, we report a novel and facile vapor phase polymerization (VPP) and spray-coating strategy towards the construction of a laminated film containing a PEDOT film and Ti3C2Tx MXene sheets on the fiber surface. The fabricated PEDOT/MXene decorated cotton fabrics are integrated with excellent electrochemical performance, joule heating performance, good electromagnetic interference (EMI) shielding, and strain sensing performance. The resultant multifunctional textiles have a low sheet resistance of 3.6 Ω sq-1, and the assembled all-solid-state fabric supercapacitors exhibit an ultrahigh specific capacitance of 1000.2 mF cm-2, which exceeds the state-of-the-art MXene-based fabric supercapacitors. In addition, the PEDOT/MXene modified fabrics exhibit an exceptional joule heating performance of 193.1 °C at the applied voltage of 12 V, high EMI shielding effectiveness of 36.62 dB, and high sensitivity as strain sensors for human motion detection. This work provides a novel strategy for the structure design of multifunctional textiles and will lay the foundation for the development of multifunctional wearable electronics.
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Durable electromagnetic interference (EMI) shielding is highly desired, as electromagnetic pollution is a great concern for electronics' stable performance and human health. Although a superhydrophobic surface can extend the service lifespan of EMI shielding materials, degradation of its protection capability and insufficient self-healing are troublesome issues due to unavoidable physical/chemical damages under long-term application conditions. Here, we report, for the first time, an instantaneously self-healing approach via microwave heating to achieve durable shielding performance. First, a hydrophobic 1H,1H,2H,2H-perfluorooctyltriethoxysilane (POTS) layer was coated on a polypyrrole (PPy)-modified fabric (PPy@POTS), enabling protection against the invasion of water, salt solution, and corrosive acidic and basic solutions. Moreover, after being damaged, the POTS layer can, for the first time, be instantaneously self-healed via microwave heating for a very short time, i.e., 4 s, benefiting from the intense thermal energy generated by PPy under electromagnetic wave radiation. This self-healing ability is also repeatable even after intentionally severe plasma etching, which highlights the great potential to achieve robust and durable EMI shielding applications. Significantly, this approach can be extended to other EMI shielding materials where heat is a triggering stimulus for healing thin protection layers. We envision that this work could provide insights into fabricating EMI shielding materials with durable performance for portable and wearable devices, as well as for human health care.
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Aerogel fibers with ultrahigh porosity and ultralow density are promising candidates for personal thermal management to reduce the energy waste of heating an entire room, and play important roles in reducing energy waste in general. However, aerogel fibers generally suffer from poor mechanical properties and complicated preparation processes. Herein, we demonstrate hierarchically porous and continuous silk fibroin/graphene oxide aerogel fibers (SF/GO) with high strength, excellent radiative heating performance, and thermal insulation performance through coaxial wet spinning and freeze-drying. The hollow CA/PAA fibers prepared via a coaxial wet spinning process have multiscale porous structures, which are not only beneficial for the formation of an SF/GO aerogel core, but also help to improve the mechanical strength of the aerogel fibers. Moreover, the prepared aerogel fibers show comparable porosity and mechanical properties with those of hollow CA/PAA fibers. More importantly, GO can dramatically improve the infrared radiative heating properties, and the surface temperature is increased by 2.6 °C after exposure to infrared radiation for 30 s, greatly higher than that of hollow fiber and SF aerogel fibers. Furthermore, the integration of hierarchically porous hollow fibers and SF/GO aerogels prevents thermal convection, decreases thermal conduction, and suppresses thermal radiation, rendering the SF/GO aerogel fiber with excellent thermal insulation performance. This work may shed light on the heat transfer mechanism of the microenvironment between the human body and textiles and pave the way for the fabrication of high-performance aerogel fibers used for personal thermal management.
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Antibacterial fibers have great potential in many applications, such as medical dressings, surgical sutures and masks, etc. owing to their good growth inhibition against bacteria. However, for the fabrication of antibacterial fibers, the traditional inorganic nanoparticles coating method shows the disadvantages of high cost, low stability and binding fastness. Herein, we develop a facile, scalable and cost-effective blend spinning strategy to fabricate the highly effective antibacterial zeolitic imidazolate framework-8@alginate (ZIF-8@SA) fibers through wet spinning of the mixture of ZIF-8 and SA. The fabricated ZIF-8@SA fibers show high antibacterial efficiency, good durability and high tensile strength. The antibacterial performance of ZIF-8@SA fibers is superior to the most reported inorganic nanoparticles modified fibers. The excellent antibacterial performance of ZIF-8@SA fibers is attributed to the reactive oxygen species from the ZIF-8 and the swelling of SA. This work may shed light on the antibacterial mechanisms of metal organic frameworks and pave the way for the development of high-performance, durable and highly effective antibacterial textiles.
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Alginatos/farmacologia , Antibacterianos/farmacologia , Escherichia coli/efeitos dos fármacos , Estruturas Metalorgânicas/farmacologia , Zeolitas/farmacologia , Alginatos/química , Antibacterianos/química , Estruturas Metalorgânicas/química , Testes de Sensibilidade Microbiana , Tamanho da Partícula , Propriedades de Superfície , Têxteis , Zeolitas/químicaRESUMO
Tau hyperphosphorylation is a main cause of neuronal loss in Alzheimer's disease, which can be caused by many factors, including oxidative stress. The multifunctional protein p62, which exists in neurofibrillary tangles and causes aggregation of hyperphosphorylated tau, not only serves as a receptor in selective autophagy, but also regulates oxidative stress. However, whether p62 participates in oxidative stress-induced tau hyperphosphorylation remains unclear. In this study, we produced an Alzheimer's disease rat model by injecting ß-amyloid protein into the hippocampus and ß-galactose intraperitoneally. Hematoxylin-eosin staining was used for morphological analysis of brain tissue, and western blotting, immunohistochemistry and reverse transcription-PCR were employed to study p62 and autophagy related proteins, antioxidant defense system kelch-like ECH-associated protein 1-NF-E2-related factor 2 related proteins and hyperphosphorylated tau, respectively. The number of neurons in the brain decreased in Alzheimer's disease rats, and the autophagy related proteins Atg12-Atg5, microtubule-associated protein 1 light chain 3-phosphatidylethanolamine and Beclin1 increased significantly, while p62 expression reduced. Expression of kelch-like ECH-associated protein 1 increased, NF-E2-related factor 2 protein and the downstream gene products of glutamate cysteine ligase catalytic subunit and glutamate cysteine ligase modulatory subunit decreased, and hyperphosphorylated tau increased. These findings demonstrate that autophagy levels increased and p62 levels decreased in the brains of Alzheimer's disease rats. Moreover, the anti-oxidative capability of the NF-E2-related factor 2-antioxidant response element pathway was decreased, which may be the cause of tau hyperphosphorylation in Alzheimer's disease brain tissue and the subsequent structural and functional damage to neurons.