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•ANFs-reinforced BC membranes were prepared by a trivial vacuum-filtration process.•ANFs@BC modified by Ag NWs exhibited superior conductivity and conductive stability.•Ag/ANFs@BC ...pressure sensor with good flexibility could monitor human body motion.•Ag/ANFs@BC pressure sensor showed excellent sensitivity and cycling stability.
Wearable electronic sensors, especially piezoresistive pressure sensors, have attracted tremendous attention due to their portability, flexibility, and high sensitivity to slight changes in pressure. However, these sensors suffer from fabrication procedures as well as poor mechanical properties, pressure sensitivity. Herein, an aramid nanofiber (ANF)-reinforced bacterial cellulose (BC) nanocomposite membrane (ANFs@BC) was prepared by a simple vacuum-filtration self-assembly process. Compared to the untreated BC, the tensile strength of the resulting ANFs@BC increased from 36.3 to 58.3 MPa, corresponding to a 60.6% increase, which indicated that the ANFs reinforced the structure of the BC membrane. The flexible and strong ANFs@BC was further modified by silver nanowires (Ag NWs) to prepare the Ag/ANFs@BC, which was used as the pressure sensor. The prepared pressure sensor exhibited suitable antibacterial properties, high pressure sensitivity and remarkable long-term stability without any distinct decline in sensitivity, after a constant applied pressure of 5 kPa for 6000s. When being applied to the human body, the pressure sensor was capable of accurately recognizing different mechanical stimuli, which highlighted the promising potential of the sensor for use in human motion monitoring. This work provided a novel and efficient pathway to prepare the ANFs@BC with powerful mechanical properties. Besides, the Ag/ANFs@BC as the pressure sensor exhibited great value for use in wearable electronics.
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Persistent inflammation and bacterial infection commonly occur during the wound healing process, necessitating urgent development of effective strategies for treating drug-resistant ...bacterial infections. In this study, bismuth vanadate (BiVO4) was successfully synthesized as an antibacterial agent that promotes wound healing. Through In vitro antibacterial experiments, it was observed that the prepared BiVO4 exhibited excellent performance in catalyzing H2O2 to produce hydroxyl radicals (OH) at a lower concentration (0.2 mg mL−1), resulting in significant antibacterial effects against Gram-negative Extended-Spectrum β-Lactamases-Producing Escherichia coli (ESBL-E. coli) strains. Furthermore, biosafety tests, cell scratch experiments, and ESBL-E. coli infected wound rat model experiments demonstrated high biocompatibility of BiVO4 with a cell survival rate exceeding 85 %. Additionally, BiVO4 promoted the production of vascular endothelial growth factors and fibroblasts migration while contributing to collagen production, effectively facilitating immune reconstruction at the wound site. By integrating peroxidase (POD)-like under acidic conditions (pH 4) and catalase (CAT)-like catalytic activities at under neutral conditions (pH 7), BiVO4 exhibited the ability to activate free radical sterilization and accelerate wound healing by activating O2. Therefore, our findings provide evidence for a dual enzyme regulatory mechanism involving antibacterial properties and promotion of wound tissue reconstruction for potential application in both antibacterial treatment and wound healing.
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•This review provides information how to improve the performance of medical implants.•Noble metals are analyzed as multifunctional biocompatible and antibacterial materials.•Critical ...assessment of the approaches to the modification of implant surfaces is given.
This review provides information on the use of noble metals, as well as silver and gold nanoparticles to improve the performance of medical implants related to orthopedic and reconstructive surgery. Traditionally, modern biomaterials used for implantation in various fields of medicine are metals and alloys, ceramics, carbon materials, polymers and composites. The existing limitations for the practical application of these materials are also analyzed and various alternatives are discussed. The main attention is paid to the analysis of experimental results on investigation of noble metals (Ir, Pt, Pd, Ag, Au) as multifunctional biocompatible and antibacterial materials in medical practice. In contrast to recent reviews that discussed individual classes of implantable materials or properties and applications of metal nanoparticles, this review attempts to generalize data on the modification of implant surfaces by thin films of platinum group metals and silver or gold nanoparticles. The formation of the “implant of the future” requires a comprehensive approach and solution of interrelated tasks, including selection of effective implant materials and methods of implant surface modification. This review is expected to promote further interest of researchers who are involved in the current level of evaluation and selection of modern biomaterials for medical implant applications.
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•Novel bacterial cellulose/poly (vinyl alcohol)/chitosan films were developed.•The effects of chitosan as a bulk solution and nanoparticles were compared.•Incorporation of chitosan ...nanoparticles provided the best antibacterial activity.•Bulk chitosan improved the mechanical properties of the films.•Chitosan nanoparticles enhanced optical barrier properties against UV radiation.
Ternary composite films containing bulk chitosan (CS) and chitosan nanoparticles (CSNPs) with different concentrations were prepared using bacterial cellulose/poly(vinyl alcohol) as the base film and the composites films were compared. The micromorphology and mechanical, physical, chemical, antibacterial, and optical barrier properties of the composite films were compared. CS incorporation improved the mechanical properties, as the maximum tensile strength was increased to 130.55 ± 9.42 MPa. The dense structure of CSNPs prevented water diffusion and lessened the water content of the composite membranes. The inclusion of CS and CSNPs both reduced the water solubility and water vapor permeability. CS-doped films possessed good transparency, while CSNPs had better ultraviolet-barrier properties (3.84 % of transmittance at 200–280 nm). In addition, CSNPs-embedded membranes exhibited prominent antibacterial properties against Escherichia coli and Staphylococcus aureus, which were much greater than those of CS composite membranes with a maximum bacteriostatic diameter of 10.33 ± 1.55 mm.
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•The effects of different divalent ions cross-linked SA-PAM on antibacterial properties and wound healing were investigated.•Mechanism abilities of different divalent ions ...cross-linked hydrogels on wound healing.•Zinc cross-linked hydrogels had antibacterial activity and better mechanical strength.•Strontium and zinc ions cross-linked hydrogels stimulated vascular repair and reduced wound inflammation by detecting the VEGF and TGF-β expression.
Hydrogels are widely used as debriding agents on account of providing a moist environment for wound healing, however the lack of mechanical strength, angiogenesis and antibacterial property limits their applications. In this study, we synthesized novel divalent ion cross-liking hydrogels (copper, zinc, strontium and calcium) and compared the mechanical performance, swelling ratio, antibacterial properties and biocompatibility in vitro and vivo. Thereinto, among the four divalent ions cross-linked hydrogels, copper ion crosslinking exhibited the maximum breaking strength, while strontium and zinc ion cross-linked hydrogels exhibited an excellent mechanical strength. In addition, the swelling ratio and pore size of no-ion cross-linked hydrogels was larger than ion cross-kinked hydrogels. In vitro, the improvements on wound healing after hydrogel application were evaluated by histological and molecular assays by detecting VEGF and TGF-β expression. In vitro and in vivo study results showed that zinc cross-kinked hydrogel had a spectrum of antibacterial activities, cell viability, mechanical strength and the ability of wound closure by promoting fibroblasts migration, vascularization, collagen deposition and the formation of granulation tissue.
We report an unprecedented, eco-friendly, in situ activatable model antibiotic, phenylalanyl-polyethylenimine (PhePEI), to potentially diminish antibiotic pollution of the environment and associated ...antibiotic resistance. The inactive PhePEI can be reversibly activated upon supramolecular crosslinking by cucurbit8uril, conferring potent antibacterial activity.
Skin is the first line of defense against pathogenic microorganisms. Any serious damage to this organ can lead to bacterial invasion and wound infection. Such infections can cause not only a delay in ...the healing process, but also more serious complications such as tissue necrosis or even sepsis, which can lead to life-threatening conditions. Therefore, wound management is a clinically critical issue. In this regard, scaffolds containing antibacterial nanobiomaterials or other agents have emerged as effective methods for reducing wound bacterial colonization and infection, thus enhancing wound healing. Because of their immunological safety, biodegradability and non-toxicity, polysaccharide-based scaffolds have piqued the interest of researchers for the delivery of antibacterial agents and nanobiomaterials for wound healing applications. This review focuses on antibacterial nanobiomaterials and agents, as well as their delivery via polysaccharide-based scaffolds for wound healing applications.
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•Delivery of antibacterial agents has been widely investigated for the treatment of infected wounds.•Polysaccharides are highly biocompatible materials that could be used for the delivery of antibacterial agents.•Various approaches have been developed for the delivery of antibacterial agents for wound healing applications using polysaccharide-based scaffolds.•Crosslinking of carbohydrate polymers plays an important role in the fabrication of hydrogels for skin tissue engineering.
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•HKUST-1@ LCNFs was fabricated through green and in-situ strategy successfully.•CA composite membranes were prepared with blending of HKUST-1@ LCNFs successfully.•CA composite ...membranes blended with HKUST-1@ LCNFs exhibit excellent ultrafiltration performances.•M7 has high antibacterial properties attributed to the synergistic effect of the LCNFs and HKUST-1.
To expand the application of cellulose acetate (CA) membranes in wastewater treatment, the excellent ultrafiltration performance and anti-fouling properties should be achieved. Firstly, HKUST-1@ lignocellulose nanofibrils (LCNFs) was fabricated through green and in-situ strategy successfully, which combine the characteristics of the HKUST-1 and LCNFs. Then, the blended ultrafiltration membranes with different loading of HKUST-1@LCNFs (or HKUST-1, LCNFs) were prepared by the process of phase separation, which exhibit improved pore structure, hydrophilicity, and rejection rate. Excitedly, the highest pure water permeability of 207.32 L·m−2·h−1 and the flux recovery ratio (FRR) of 90.56% were obtained with M6 membrane (0.55 wt% HKUST-1@LCNFs), which was better than that of M2 (HKUST-1) and M3 (LCNFs). It is confirmed that HKUST-1 could inhibit the accumulation of LCNFs, making it taking advantages of its hydrophilic groups. Moreover, composite membranes have attractive antibacterial properties, and >90% of E. coli were killed by M7. This work demonstrated that CA membranes blended with HKUST-1@LCNFs possesses great potential in the wastewater treatment process.
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