Superior Antibacterial Properties Research Articles

Biomimetic Silicone Surfaces for Antibacterial Applications

Biomimetic patterning emerges as a promising antibiotic-free approach to protect medical devices from bacterial adhesion and biofilm formation. The main advantage of this approach lies in its simplicity and scalability for industrial applications. In this study, we employ it to produce antibacterial coatings based on silicone materials, widely used in the healthcare industry. In doing so, we patterned silicone substrates with a topography of various flower petals (rose, chamomile, pansy, and magnolia) and studied the relationship between the antibacterial properties of the obtained biomimetic substrates and their surface topography. To study the surface topography of biomimetic surfaces, we used the fractal analysis of their SEM images. In particular, as a measure of surface complexity and heterogeneity, we used the values of the developed interfacial area ratio (Sdr) and lacunarity coefficient (β). In the result, we found that the bacterial area coverage of biomimetic substrates decreased exponentially with the increase in their surface complexity and heterogeneity, and prominent antibacterial properties were observed at β > 1.6 and Sdr > 50. The results of this study can be used to identify biomimetic materials with superior antibacterial properties and produce efficient antibacterial silicone coatings for biomedical and healthcare applications.

Eco-friendly dyeing of cotton fabrics with microbial pigments: Anionic modification for superior color, antibacterial, hydrophobic and UV protection properties

Eco-friendly dyeing of cotton fabrics with microbial pigments: Anionic modification for superior color, antibacterial, hydrophobic and UV protection properties

Medical-grade honey has superior antibacterial properties against common bacterial isolates in wound cultures of dogs and cats in comparison to non-medical-grade honey types.

To compare the antibacterial activities of different types of honey against common bacterial isolates cultured from wounds of dogs and cats. 4 types of honey were used including a medical-grade manuka honey, a non-medical-grade manuka honey, a locally sourced non-medical-grade honey (non-MGH), and a commercially sourced non-MGH. Bacterial isolates were obtained from clinical wound cultures of dogs and cats including Staphylococcus pseudintermedius, Escherichia coli, Enterococcus faecalis, and Pseudomonas aeruginosa. The macro-broth dilution method was used to analyze the MIC and minimum bactericidal concentration. The percentage of growth inhibition was assessed for different types of honey at different concentrations using a generalized linear regression model. Medical-grade honey exhibited the lowest minimum bactericidal concentration against S pseudintermedius, E faecalis, and P aeruginosa, alongside the lowest MIC at 90% with statistically significant higher bacterial growth inhibition in medium and low concentrations. Non-medical-grade manuka honey had a similar bactericidal activity against S pseudintermedius and P aeruginosa compared to locally and commercially sourced non-MGH. In this in vitro study, MGH exhibited superior antibacterial activity against all bacterial isolates compared to other types of honey. Medical-grade honey displayed the greatest antibacterial activity against common wound pathogens and could be considered over other types of honey for wound management in cats and dogs. Locally and commercially sourced non-MGH appears to have a comparative efficacy against certain bacteria compared to non-medical-grade manuka honey and is more cost effective. Further in vivo studies are needed to confirm these findings.

Enhancing Photothermal Therapy for Antibiofilm Wound Healing: Insights from Graphene Oxide-Cranberry Nanosheet Loaded Hydrogel in vitro, in silico, and in vivo Evaluation.

Diabetic foot ulcers present a formidable challenge due to colonization by biofilm-forming microorganisms, heightened oxidative stress, and continuous wound maceration caused by excessive exudation. To address these issues, we developed a robust, stretchable, electro-conductive, self-healing, antioxidant, and antibiofilm hydrogel. This hydrogel was synthesized through the crosslinking of polyvinyl alcohol (PVA) and chitosan (CH) with boric acid. To enhance its antimicrobial efficacy, graphene oxide (GO), produced via electrochemical exfoliation in a zinc ion-based electrolyte medium, was incorporated. For optimal antibiofilm performance, GO was functionalized with cranberry (CR) phenolic extracts, forming a graphene oxide-cranberry nanohybrid (GO-CR). The incorporation of GO-CR into the hydrogel significantly improved its stretchability (280% for PVA/CH/GO-CR compared to 200% for PVA/CH). Additionally, the hydrogel demonstrated efficient photothermal conversion under near-infrared (NIR) light, enabling dynamic exudate removal, which is expected to minimize retained exudate between the wound and the dressing, reducing the risk of wound maceration. The hydrogel effectively reduced levels of lipopolysaccharide (LPS)-induced skin inflammation markers, significantly lowering the expression of NLRP3, TNF-α, IL-6, and IL-1β by 39.2%, 31.9%, 41%, and 52.3%, respectively. Histopathological and immunohistochemical analyses further confirmed reduced inflammation and enhanced wound healing. The PVA/CH/GO-CR hydrogel exhibits multifunctional properties that enhance wound healing ulcers. Its superior mechanical, antibacterial, and anti-inflammatory properties and ability to promote angiogenesis make it a promising candidate for effective wound management in diabetic patients.

Development of AgFeO2/g-C3N4/RGO nanocomposites with superior photocatalytic activity and antibacterial properties for wastewater treatment

This research investigates the synergistic photocatalytic efficiency of AgFeO2/g-C3N4/RGO ternary nanocomposites (AGR NCs) for the effective degradation of Reactive Black (RB5) dye and their antibacterial activity, aiming to advance their environmental applications. The nanocomposites were synthesized using a straightforward hydrothermal method and characterized by various techniques including X-ray Diffraction (XRD), X-ray Photoelectron Spectroscopy (XPS), Fourier-transform infrared spectroscopy (FTIR), Scanning Electron Microscopy with Energy Dispersive X-ray Spectroscopy (SEM-EDX), High-resolution Transmission Electron Microscopy (HRTEM), Ultraviolet-Visible Diffuse Reflectance Spectroscopy (UV-DRS) and Photoluminescence (PL) Spectroscopy to assess their structural, morphological, and optical characteristics. The photocatalytic activity was tested by degrading RB5 dye in water. The findings reveal that the AGR NCs exhibit a substantially improved photocatalytic performance compared to AgFeO2 (AgF), AgFeO2/g-C3N4 (AG) and AgFeO2/RGO (AR) nanocomposites. The synergistic effect is attributed to the formation of a heterojunction structure that promotes efficient separation and transfer of photoinduced electron-hole pairs. The reduced graphene oxide (RGO) serves as an excellent electron conductor, further enhancing the charge separation and extending the lifetime of the charge carriers. Photocatalytic experiments revealed that the AGR NCs achieved 95.5 % degradation of RB5 dye within 120 min. The degradation kinetics followed a Pseudo-first-order model, indicating that the efficient and abundant generation of reactive oxygen species (ROS) was responsible for the dye degradation, as confirmed by quenching experiments. Additionally, the AGR NCs exhibit strong antibacterial activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). This study provides insights for designing efficient UVA-driven photocatalysts for environmental treatment purposes.

Green Synthesis of Terminalia ferdinandiana Exell-Mediated Silver Nanoparticles and Evaluation of Antibacterial Performance.

This study uses a novel method in which extracts from different parts of a single plant are used to synthesize well-defined silver nanoparticles (AgNPs) to address the lack of capping agents in certain plant extracts. We focused on synthesizing AgNPs with enhanced biomedical activity using aqueous leaves and fruit extracts of Terminalia ferdinandiana Exell, a plant native to northern Australia that is known for its high phenolic content and associated health benefits. The impact of using parameters such as the Ag+ ion-to-extract ratio and pH on AgNP synthesis was examined. The formation of AgNPs was confirmed using UV-visible spectrophotometry, transmission electron microscopy, and dynamic light scattering. The AgNPs synthesized at a pH of 8 and 1:25 Ag+/extract ratio exhibited the lowest particle size and polydispersity index. The AgNPs synthesized with leaf extract (AgKL) were monodisperse and exhibited a smaller hydrodynamic diameter (37 nm) compared to the fruit extract nanoparticles (AgKP), which were polydisperse and larger (147 nm). Phytochemicals in T. ferdinandiana aqueous leaf extract act as effective capping and stabilizing agents, enabling the synthesis of small-sized and homogenous AgNPs, which the fruit extract alone could not achieve. The in vitro bioactivity was evaluated using antioxidant and antibacterial assays and compared with the crude extract. Both the AgNPs and T. ferdinandiana extracts demonstrated strong 2,2 diphenyl-1-picrylhydrazyl radical scavenging activity. However, only AgKL showed excellent antibacterial activity against Gram-negative and Gram-positive bacteria based on minimum inhibitory and bactericidal results. Mixing 50% leaf extract with fruit extract resulted in well-stabilized NPs (AgKPL) with a hydrodynamic diameter of 33.4 nm and superior antibacterial properties. These results indicate that AgKL and AgKPL have significant potential for pharmaceutical and biomedical applications.

Scalable Processing of Glass with Multi‐Functional Cu Coating

AbstractFunctional glass has been intensively studied as a future material with improved comfort, safety, and practicality across a variety of settings, including industrial, and residential environments. The integration of copper coatings on glass is noteworthy for its broad‐spectrum germicidal properties. When applied to frequently touched surfaces, this copper‐enhanced glass plays a crucial role in controlling infections, underscoring its significance in healthcare and public health contexts. Herein, an innovative approach for processing multifunctional copper coating on glass through atmospheric plasma spraying (APS) is introduced. The Cu coating demonstrates remarkable bactericidal efficiency against both Gram‐positive and Gram‐negative bacteria, achieving a 99.9% inhibition rate within 5 h. Moreover, the coating maintains its biocidal effectiveness for up to 3 days against these bacterial strains. The Cu coated glass also incorporates an electrical heating function. This feature allows the glass to increase its surface temperature by ≈7 °C with a minimal power load of 2V. The coating's transparency is variable and can be adjusted through the APS parameters, depending on the desired copper surface coverage. The combination of superior antibacterial properties and electrical heating capability makes the Cu coated glass as high‐performance material for medical applications, offering dual functions of infection control and temperature regulation.

The electrostatically self-assembled C60(OH)n-Ca nanoparticles exhibit superior photodynamic antibacterial properties and cytocompatibility

Carbon nanomaterial is a momentous field of current biomedical research. However, extensive exploration is still required to endow carbon nanomaterial with both antibacterial properties and biological safety. In this study, fullerenol and calcium ions were synthesized into C60(OH)n-Ca nanoparticles through an electrostatic self-assembly strategy. Morphological and chemical analyses revealed that the C60(OH)n-Ca nanoparticles contained 4.52 at.% Ca, with a minimum size of approximately 10 nm. The electrostatic self-assembly did not alter the chemical structure of the fullerenol. The photodynamic antibacterial effect of the C60(OH)n-Ca nanoparticles was concentration-dependent, showing antibacterial rates of 94 % and 96.6 % against Escherichia coli and Staphylococcus aureus at a concentration of 100 μg/mL, while the antibacterial effect was unsatisfactory under dark conditions. Additionally, C60(OH)n-Ca nanoparticles promoted the proliferation of MC3T3-E1 cells, demonstrating desirable biological safety. The C60(OH)n-Ca nanoparticles synthesized in this article achieved a balance between antibacterial and cytocompatibility, thus possess potential applications in biomedical fields.

Preparation and performance of fluorescent-assisted photocatalytic self-cleaning coatings for enhanced NO degradation

Long afterglow materials have been utilized to reduce the dependence of photocatalytic air purification technology on light sources, but research on the synergistic application of light storage and visible light catalytic materials in self-cleaning coatings is limited. In this work, stable visible light catalytic material, (C3N4/Bi2WO6), was selected as the catalytic material. The afterglow powder mainly composed of strontium aluminate (SA) was used as a light storage material. A ternary composite photocatalytic material SA/C3N4/Bi2WO6 (SCBW) was prepared, which can work in both light and dark environments. Epoxy resin was introduced to construct coatings containing SCBW (CSCB). The high catalytic activity of SCBW is attributed to the heterojunction effect of various semiconductors and the improved interface, resulting in a degradation rate of nitrogen oxides (NO) reaching 75 % and proving the degradation effect on formaldehyde aqueous solution and organic dyes. Additionally, the synergistic effect of fluorescence characteristics and photocatalytic ability endow the material with superior antibacterial properties, while the self-cleaning functionality of CSCB enhances the durability of the coating. Finally, the mechanism of fluorescence-assisted enhanced photocatalytic self-cleaning coating was discussed, providing insights into the design of multifunctional photocatalytic self-cleaning coatings for air purification and pollutant separation.

Light-responsive antibacterial dissolving microneedles loaded with 5-aminolevulinic acid and silver nanoparticles for the treatment of acne

Acne is a chronic inflammatory disease of pilosebaceous unit, which can be aggravated by hyperkeratosis of the pilosebaceous unit, excessive secretion of sebum and the proliferation of Propionibacterium acnes (P. acnes). Traditional drug treatment methods commonly exhibit drawbacks, including bacterial resistance and poor transdermal permeability, resulting in suboptimal efficacy and recurrent infections. Herein, we designed a dual drug-loaded microneedles patch to deliver ALA and silver nanoparticles for acne treatment. The comprehensive treatment of acne is achieved by utilizing the safe and efficient advantages of 5-aminolevulinic acid (ALA) photodynamic therapy (PDT), coupled with the superior antibacterial properties of silver nanoparticles. To enhance drug permeability, dissolving microneedles (DMNs) are employed for targeted and efficient drug delivery. In vitro and in vivo experiments demonstrated that DMNs loaded with both AgNPs and ALA-PDT (ALA/AgNPs@DMNs) have significant antibacterial activity, along with superior drug loading capacity and penetration. The application of ALA/AgNPs@DMNs in treating acne-affected rats alleviates excessive epidermal keratinization, effectively inhibits bacterial growth, and significantly improves acne symptoms. This suggests that the “dissolving microneedle” formulation holds promise for the treatment and management of acne.

Progress in the Application of Multifunctional Composite Hydrogels in Promoting Tissue Repair.

Tissue repair is an extremely complex process, and effectively promoting tissue regeneration remains a significant clinical challenge. Hydrogel materials, which exhibit physical properties closely resembling those of living tissues, including high water content, oxygen permeability, and softness, have the potential to revolutionize the field of tissue repair. However, the presence of various complex conditions, such as infection, ischemia, and hypoxia in tissue defects, means that hydrogels with simple structures and functions are often insufficient to meet the diverse needs of tissue repair. Researchers have focused on integrating multiple drugs, nanomaterials, bioactive substances, and stem cells into hydrogel matrices to develop novel multifunctional composite hydrogels for addressing these challenges, which have superior antibacterial properties, hemostatic abilities, self-healing capacities, and excellent mechanical properties. These composite hydrogels are designed to enhance tissue repair and have become an important direction in the current research. This review provides a comprehensive review of the recent advances in the application of multifunctional composite hydrogels in promoting tissue repair, including drug-loaded hydrogels, nanomaterial composite hydrogels, bioactive substance composite hydrogels, and stem cell composite hydrogels.

Development and evaluation of antibacterial nanofiber membranes via coaxial electrospinning for enhanced air filtration performance

As industrialization intensifies and the population soars, the challenge of air pollution escalates into a pressing concern. Electrospun nanofiber membranes, owing to their distinctive attributes including high specific surface area, porosity, and uniform pore size distribution, have emerged as promising candidates for air filtration. In this study, we successfully prepared ZnO@polyvinylidene fluoride-co-hexafluoropropylene (PVDF-HFP) antibacterial nanofiber membranes through a combined solvothermal and coaxial electrospinning approach. The structure and performance of these nanofiber membranes were systematically modulated by adjusting the shell feeding rate and zinc acetate dihydrate (Zn(Ac)2·2H2O) concentration. Specifically, an increase in the shell feeding rate led to a decrease in fiber diameter, accompanied by the proliferation of nano-beads, thereby contributing to a reduction in membrane pore size. Consequently, a heightened shell feeding rate correlated positively with both filtration efficiency and pressure drop. Furthermore, the incompletely reacted Zn(Ac)2·2H2O enhanced the conductivity of the spinning solution, facilitating a decrease in pore size and enhancing air filtration performance. In summary, when the shell feeding rate was 0.60 mL h−1 and Zn(Ac)2·2H2O concentration was 1.5 wt%, the obtained ZnO@PVDF-HFP nanofiber membrane exhibited superior air filtration performance, with high filtration efficiency of 99.91 %, low pressure drop of 80.70 Pa and noteworthy quality factor of 0.08781 Pa-1. Notably, these membranes sustained their high filtration efficiency and low pressure drop even after 40 min of continuous testing, underscoring their exceptional stability. In addition, the obtained nanofiber membrane exhibited robust antibacterial activity against both Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus), demonstrating their multifaceted potential. Our work not only simplifies the fabrication process of electrospun nanofiber membranes with superior air filtration and antibacterial properties but also highlights their potential as innovative alternatives to conventional air filter materials, poised for diverse practical applications.

Novel biocompatible magnetron-sputtered silver coating for enhanced antibacterial properties and osteogenesis in vitro

Peri-implant infection is a serious complication in orthopedic surgery. This study aimed to reduce the incidence of peri-implant infection by developing a durable and safe antibacterial silver coating. We compared the antibacterial properties and process controllability of various coating techniques to identify the most effective method for silver coating. We refined substrate treatment techniques and coating thicknesses through antibacterial and scratch tests. Scanning electron microscopy (SEM) and energy-dispersive X-ray spectroscopy (EDS) were used to analyze the coating’s morphology and composition. Micron-sized magnetron sputtering silver coating samples underwent in vitro antibacterial testing, cytotoxicity testing, silver ion release testing, and osteogenic testing using membrane contact culture, CCK-8 assay, inductively coupled plasma (ICP) detection, and alkaline phosphatase (ALP) activity/osteogenic gene PCR. Magnetron sputtering demonstrated superior antibacterial properties, uniformity, and process controllability compared to alternative techniques. The optimal adhesion strength was achieved with a 0.5 μm coating thickness and a 400 mesh sandpaper pretreatment process, without compromising antibacterial efficacy. The coating showed near-perfect antiseptic results in antibacterial and anti-biofilm tests. Fibroblasts cultured in silver ion precipitation medium exhibited growth rates of 89% on day 30 and 88% on day 90, compared to 95% in the control group. The osteogenic test indicated that the magnetron sputtering silver coating promotes osteogenesis effectively. Our study demonstrated that micron-sized magnetron sputtering silver coating has potential for clinical use to prevent peri-implant infections in the future.

Chemical constituents and biological activities of endophytic fungi from Fagopyrum dibotrys.

Fagopyrum dibotrys is an important wild food and feed germplasm resource. It has high nutritional and medicinal value and is rich in natural products, including flavonoids, phenolic acids, coumarins, and alkaloids. Endophytic fungi in F. dibotrys have emerged as valuable sources of natural products. However, studies on the biological activity and chemical composition of these endophytic fungi remain limited. In this paper, a new method to obtain natural active ingredients by fermentation of endophytic fungi from medicinal plants was proposed. Then the antioxidant and pathogenic activities of the endophytic fungi extracts were determined in vitro. In addition, secondary metabolites produced by endophytic fungi with medicinal activity were analyzed by high performance liquid chromatography-tandem mass spectrometry (LC-MS). Among the 95 endophytic fungal strains in F. dibotrys, four strains with high phenol yields were selected by reaction: Alternaria alstroemeriae (J2), Fusarium oxysporum (J15), Colletotrichum karsti (J74), and Colletotrichum boninense (J61). Compared with those of various extracts, the ethyl acetate fractions of A. alstroemeriae (J2), F. oxysporum (J15), and C. boninense (J61) exhibited superior antioxidant and antibacterial properties. The results indicated that the fungal extract was an excellent natural antioxidant and might be a potential antibacterial agent. The DPPH free radical clearance of A. alstroemeriae was 94.96 ± 0.004%. These findings indicated that A.alstroemeriae had strong antioxidant activity. In addition, the extract of A.alstroemeriae had good antibacterial activity against Escherichia coli and Staphylococcus aureus, with MICs of 0.5 and 0.05 mg/mL, respectively. The chemical constituents of the ethyl acetate extract from A. alstroemeriae were further analyzed by liquid chromatography-mass spectrometry (LC-MS). We noted that A. alstroemeriae can create a variety of medicinal substances that have high value in medicine, such as caffeic acid (884.75 ng/mL), 3-phenyllactic acid (240.72 ng/mL) and norlichexanthone (74.36ng/mL). In summary, many valuable active substances and medicinal substances can be obtained through the study of endophytic fungi of F. dibotrys.

Pectin/Alginate bio-nanocomposite hydrogel beads based on in-situ formed layered double hydroxide in the presence of Mentha extract: Antibacterial carrier for potential pH-responsive targeted anti-cancer drug delivery

This research presents the creation of novel pH-responsive drug delivery carriers with potential applications in cancer treatment. The study involved the Mentha Extract (ME) for the in-situ synthesis of Layered Double Hydroxide (LDH) bio nanoparticles (LDH-ME NPs). These NPs were incorporated into a biopolymeric hybrid formulation containing Pectin and Alginate to produce bio-nanocomposite hydrogel beads. The morphology and chemical composition were assessed and confirmed through various techniques. Doxorubicin (DOX) was employed as a representative anti-cancer medication to investigate the controlled drug release properties of the newly developed hydrogel beads (loading capacity: ∼92 %). In vitro experiments revealed that the drug release pattern was significantly regulated in response to pH levels (with a higher drug release rate at pH 7.4, about 89 %). The assessment for antibacterial properties validated the effective antibacterial performance of the hydrogel beads toward S. aureus and E. coli with inhibition zones about 20 mm and 14 mm, respectively. MTT assay indicated a high level of cytocompatibility with HT-29 cells (cell viability exceeding 95 %) for the blank bio-nanocomposite hydrogel beads. Conversely, bio-nanocomposite hydrogel beads loaded with DOX exhibited notable cytotoxicity (∼13 % cell viability in 15.6 µg/mL) against HT-29 cells. These findings recommend the current bio-nanocomposite as a promising bio-platform with superior antibacterial and anti-cancer properties.

A green approach for dyeing cotton fabrics using synthesized reactive disperse dyes and their mixtures under supercritical CO2 medium.

Dyeing natural fabrics using supercritical carbon dioxide is challenging, especially without essential color hues. This work demonstrated that two newly developed reactive disperse dyes with distinct colors and shades were generated, one of which featured from the anthraquinone family and the other yellow, containing a pyrazole moiety. These new dyes and their combinations were used to dye cotton fabric using supercritical carbon dioxide and the highest K/S values were achieved at 8.73 for the mixture of (blue dye: yellow dye 80:20), however the lowest K/S was observed at 7.71 for (blue dye: yellow dye 20:80). The new dyes' chemical compositions were identified using elemental and spectroscopic analyses. The effectiveness of these dyes and their mixtures for cotton dyeing was discussed. The dyed samples were tested for color fastness, and the results indicated that they had excellent color retention and were highly durable in washing. The increasing patterns in both dyeing rate and build-up curves show good compatibility. Furthermore, desirable shades of green can be achieved by mixing blue and yellow dyes at various ratios in supercritical CO2. The compatibility test involves calculating color difference index values for dyed cotton fabrics by utilizing various ratios of a binary mixture of dyes. Furthermore, the dyes under study and dyed samples displayed superior antibacterial properties against gram-positive and gram-negative bacteria compared to certain antibiotics used as a control. These results aligned with the quality and eco-friendly standards required by the industry without the use of water.

YgiV promoter mutations cause resistance to cystobactamids and reduced virulence factor expression in Escherichia coli

Antimicrobial resistance is one of the major health threats of the modern world. Thus, new structural classes of antimicrobial compounds are needed in order to overcome existing resistance. Cystobactamids represent one such new compound class that inhibit the well-established target bacterial type II topoisomerases while exhibiting superior antibacterial and resistance-breaking properties. Understanding potential mechanisms of emerging resistances is crucial in the development of novel antibiotics as they directly impact the future therapeutic application and market success. Therefore, the frequency and molecular basis of cystobactamid resistance in Escherichia coli was analyzed. High-level resistant E. coli mutants were selected and found to harbor single nucleotide polymorphisms in the promotor region of the ygiV gene, causing an upregulation of the respective protein. These stable mutations are contrary to what was observed as a resistance genotype in the structurally related albicidins, where ygiV gene amplifications were identified as causing resistance. Overexpression of YgiV in the mutants was additionally amplified upon cystobactamid exposition, showing further adaptation to this compound class under treatment. YgiV binds cystobactamids with high binding affinity, thereby preventing their interaction with the antimicrobial targets topoisomerase IV and DNA gyrase. In addition, we observed a substantial impact of YgiV on in vitro gyrase activity by leading to increased DNA cleavage and concurrent reduction in the efficacy of cystobactamids in inhibiting gyrase supercoiling activity. Furthermore, we identified co-upregulation of membrane-modifying proteins, such as EptC, and the transcriptional regulator QseB. This presumably contributes to the observed reduced motility and fimbrial protein expression in resistant mutants, resulting in a reduced expression of virulence factors and potentially pathogenicity, associated with ygiV promotor mutations.

Sustainable calcium gluconate-based coatings for lyocell fabrics with superior flame retardancy, antibacteria and wearing properties

Sustainability and high performance of flame retardants for lyocell fabrics were still difficult to balance. Here, the full bio-based coatings (PACG) for lyocell fabrics with superior efficient flame-retardant, antibacterial and wearing properties were prepared by phytic acid (PA) and calcium gluconate (CG) in the water solvent. The fire safety of PACG/Lyocell fabrics was remarkably enhanced with an increase in limiting oxygen index (LOI) to 28.7 % when the weight gain was only 4.8 wt%. Meanwhile, PACG/Lyocell fabrics do well work on the heat and smoke release inhibition deriving from the satisfactory synergistic effect of PACG between fast formation of dense residuals and a large release noncombustible gas. Additionally, the existence of calcium ion in the PACG endowed the Lyocell fabrics with excellent antibacterial activity, where the antibacterial properties of Staphylococcus aureus (S. aureus) reached to 99.99 %. Moreover, after 100 dry friction cycles, PACG/Lyocell fabrics still maintained superior flame retardancy and antibacterial properties. More interestingly, unlike other treatment, this efficient and mild treatment method did not deteriorate the whiteness, moisture regain, and wearing properties of lyocell fabrics, which offered a simple and eco-friendly way to obtain the flame-retardant and antibacterial lyocell fabrics with well wearing properties.

Nanocomposite conductive r(GO/BSA) hydrogel as an effective dressing for rapid chronic diabetic wound healing

Conductive hydrogels, with their soft, hydrated interface and superior electrical conductivity, represent a groundbreaking solution for diabetic wound healing. However, developing a conductive hydrogel with excellent biocompatibility has proven to be challenging. This study presents the synthesis of a novel conductive hydrogel composed of bovine serum albumin (BSA) protein and graphene oxide (GO) for the treatment of diabetic wounds. The prepared hydrogel is mildly reduced by ascorbic acid to facilitate charge-transfer and enhance its conductivity. Hydrogel is optimized for enhanced mechanical and electrical properties by changing the concentration of GO within the BSA matrix. The nanocomposite hydrogel demonstrates superior antibacterial properties and enhanced biocompatibility compared to the BSA hydrogel. The prepared hydrogel is investigated for wound healing capacity in a rat model, where it demonstrates rapid healing of chronic diabetic wound. The improved therapeutic outcomes are attributed to the hydrogel's ability to facilitate cellular activities through enhanced electrical conductivity by maintaining continuous electrical signal at the wound site. The presented findings suggest that nanocomposite protein-based conductive hydrogel not only hold great potential for advanced diabetic wound care and have potential for future innovation in tissue engineering, regenerative medicine and beyond.

Developing high elongation of Ca-containing Zn alloys with superior osteogenic and antibacterial properties

The development of high-strength zinc (Zn) alloys significantly contributes to the field of orthopedics by enhancing their osteogenic properties. Calcium (Ca) is pivotal for bone composition; however, its incorporation into the Zn matrix often hampers elongation due to the formation of large-sized CaZn13 phases. In this study, two Zn alloys with different Ca contents were prepared, and their microstructures, mechanical properties, corrosion behavior and biocompatibility were investigated. Results indicate that the Zn alloy with high Ca content exhibits large-sized and high-volume-fraction CaZn13 phases, which do not significantly change during equal channel angular pressing (ECAP). The grain sizes of ECAPed Zn alloys decreased from 36.75 μm and 35.81 μm of as-cast state to 4.32 μm and 1.71 μm, respectively. Refined microstructures contributed to the improvement of mechanical properties of Zn alloys, which have elongation over 15 % higher than that of all Zn-Mg-Ca alloys reported so far. The high elongation of Zn alloys originates from the inhibition of the propagation of microcracks which generated from the Zn/CaZn13 interphase. Moreover, the formation of large-sized CaZn13 phases leads to the severe local corrosion through enhancing galvanic effect, finally increasing corrosion rate. During degradation, the release of metallic ions, such as Zn2+, Mg2+, and Ca2+, are beneficial to the cell viability and osteogenic properties. And the accelerated release of Zn2+ plays a role in antibacterial performance. These results are very helpful for promoting the application of biodegradable Zn alloys in the field of orthopedics.