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The clinical success of bioinert, tissue‐interfacing metallic implants is greatly jeopardized by complications such as infections, inflammation, and poor regeneration or biointegration, especially concerning diabetics. Implants featuring self‐renewable surfaces that sequentially dictate antibacterial/anti‐inflammatory, immunomodulatory, and pro‐healing/‐regenerative functionalities represent an emerging solution. Herein, fusing triple marine bioinspirations, namely the multilayered interlocked interfaces of mollusk shells, the adhesive/reactive chemistries of mussels, and the self‐renewing, release‐active mucus layers of corals, a self‐adaptive interfacial engineering strategy that imparts self‐renovating surfaces and temporally‐activatable biofunctionalities to various inert biometallic devices is presented. Specifically, sandwich‐like multilayered coatings are in situ constructed, comprising a substrate‐derived micro/nanostructured prelayer, a mussel‐inspired bioadhesive interlayer, and a polyphenol–antibiotic dynamically‐crosslinked therapeutic gel toplayer. The dynamic bonds within the gel allowed pH/reactive oxygen species‐responsive surface degradation, localized release of multifunctional therapeutics, and conditional exposure of cell‐supportive chemical moieties and micro/nanotopographies. Systematic in‐vitro, in‐ovo, and in‐vivo (spanning osseous, subcutaneous, and wound‐closure implantations) studies demonstrated that the functionalized bone implants or wound closure staples possessed adaptive biocompatibility (cyto‐/hemo/‐tissue‐compatibility) and biofunctionalities to combat device‐associated infections and spur diabetic tissue repair. This study underscores the potential of self‐adaptive coating strategies for orchestrating complex (even contradictory) biological functions in addressing challenging medical conditions that require implant intervention. [ABSTRACT FROM AUTHOR]

In this study, a portable plasma generator produced large‐area air plasma for treating infected wounds in BALB/c mice. Different plasma treatment times (30 s, 1 min, 3 min, and 4.5 min) were applied daily until the wounds healed completely. Results showed reduced inflammation and increased vascular endothelial growth factor (VEGF) expression in tissues treated for 1 and 3 min, promoting blood vessel proliferation and collagen fiber synthesis. However, treatment for 30 s and 4.5 min worsened inflammation and decreased VEGF expression. Overall, a 1‐min treatment was the most effective in promoting wound healing. Cold plasma shows promise for healing infected wounds, with treatment duration being a crucial factor. [ABSTRACT FROM AUTHOR]

Jing Han,1,2,* Qingxun Meng,1,2,* Taicheng Liu,1,2 Mengru Lv,1,2 Wenxuan Su,1,2 Beibei Liu,1,2 Jiannan Wu1,2 1Department of Oral Implantology, Tianjin Stomatological Hospital, School of Medicine, Nankai University, Tianjin, 300041, People’s Republic of China; 2Tianjin Key Laboratory of Oral and Maxillofacial Function Reconstruction, Tianjin, 300041, People’s Republic of China*These authors contributed equally to this workCorrespondence: Jing Han; Jiannan Wu, Department of Oral Implantology, Tianjin Stomatological Hospital, School of Medicine, Nankai University, Tianjin, 300041, People’s Republic of China, Email hanj0203@163.com; bdxiaosier@163.comBackground: Wound healing has always been a focal point in clinical work. Bacterial infections and immune microenvironment disorders can both hinder normal wound healing. Current wound dressings only serve a covering function. Developing wound dressings with antibacterial and immunomodulatory functions is crucial for aiding wound healing. To address this issue, we have developed a hydrogel with antibacterial and immunomodulatory functions for managing infected wounds.Methods: The present study describes a photo-crosslinked antibacterial hydrogel composed of curcumin, silver nanoparticles-loaded reduced graphene oxide, and silk fibroin methacryloyl for the treatment of infected wounds. The study assessed its antibacterial properties and its capacity to induce macrophage M2 polarization through in vitro and in vivo experiments.Results: The hydrogel demonstrates robust antibacterial properties and enhances macrophage M2 polarization in both in vitro and in vivo settings. Moreover, it accelerates the healing of infected wounds in vivo by stimulating collagen deposition and angiogenesis.Conclusion: Overall, this hydrogel shows great potential in managing wound infections. Keywords: infected wound healing, silk fibroin methacryloyl, curcumin, silver nanoparticles-reduced graphene oxide, immunomodulation, antibacterial

Delays in infected wound healing are usually a result of bacterial infection and local inflammation, which imposes a significant and often underappreciated burden on patients and society. Current therapies for chronic wound infection generally suffer from limited drug permeability and frequent drug administration, owing to the existence of a wound biofilm that acts as a barrier restricting the entry of various antibacterial drugs. Here, we report the design of a biocompatible probiotic-based microneedle (MN) patch that can rapidly deliver beneficial bacteria to wound tissues with improved delivery efficiency. The probiotic is capable of continuously producing antimicrobial substances by metabolizing introduced glycerol, thereby facilitating infected wound healing through long-acting antibacterial and anti-inflammatory effects. Additionally, the beneficial bacteria can remain highly viable (>80 %) inside MNs for as long as 60 days at 4 °C. In a mouse model of Staphylococcus aureus-infected wounds, a single administration of the MN patch exhibited superior antimicrobial efficiency and wound healing performance in comparison with the control groups, indicating great potential for accelerating infected wound closure. Further development of live probiotic-based MN patches may enable patients to better manage chronically infected wounds.

Yang Chong,1,2 Dong Yu,1,2 Rui Han,3 Yanxu Li,2 Yali Gu,3 Zhaoyu Lu,1,2 Fengsong Nie,1,2 Lingli Wang,1 Hengmi Cui4 1Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, 225000, People’s Republic of China; 2Department of General Surgery, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, 225000, People’s Republic of China; 3Institute of Translational Medicine, Medical College, Yangzhou University, Yangzhou, 225009, People’s Republic of China; 4Institute of Epigenetics and Epigenomics and College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, 225009, People’s Republic of ChinaCorrespondence: Yang Chong, Department of Traditional Chinese Medicine, The Affiliated Hospital of Yangzhou University, Yangzhou University, Yangzhou, Jiangsu, 225000, People’s Republic of China, Email 092016@yzu.edu.cn Hengmi Cui, Institute of Epigenetics and Epigenomics and College of Animal Science and Technology, Yangzhou University, Yangzhou, Jiangsu, 225009, People’s Republic of China, Email hmcui@yzu.edu.cnPurpose: Incorporation of luvangetin in nanoemulsions for antimicrobial and therapeutic use in infected wound healing.Patients and Methods: Luvangetin nanoemulsions were prepared by high-speed shear method and characterized based on their appearance structure, average droplet size, polydispersity index (PDI), electric potential, storage stability. Optimized formulation of luvangetin nanoemulsion by Box-Behnken design (BBD). The antimicrobial activity and antimicrobial mechanism of luvangetin nanoemulsions against common hospital pathogens, ie, Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), were investigated using luvangetin nanoemulsions. The biosafety of luvangetin nanoemulsion was evaluated through cytotoxicity, apoptosis, and reactive oxygen species (ROS) assay experiments using human normal epidermal cells and endothelial cells. Finally, the effect of luvangetin nanoemulsion on healing of infected wounds was investigated in B6 mice.Results: Luvangetin nanoemulsion formulation consists of 2.5% sunflower seed oil, 10% emulsifier Span-20 and 7 minutes of shear time, and with good stability. Luvangetin nanoemulsion produces antibacterial activity against S. aureus and E. coli by disrupting the structure of bacterial cell membranes. Luvangetin nanoemulsion are biologically safe for HaCat and HUVEC. Luvangetin nanoemulsion showed good therapeutic effect on MRSA infected wounds in mice.Conclusion: For the first time, developed a new formulation called luvangetin nanoemulsion, which exhibited superior antibacterial effects against Gram-positive bacteria. Luvangetin nanoemulsion has a favorable effect in promoting infected wound healing. We have combined luvangetin, which has multiple activities, with nanoemulsions to provide a new topical fungicidal formulation, and have comprehensively evaluated its effectiveness and safety, opening up new possibilities for further applications of luvangetin. Keywords: luvangetin, nanoemulsion, antimicrobial mechanism, infected wound healing

The development of wound dressing materials with both self-healing and antibacterial properties for promoting wound closure is highly desirable in health care. Herein, a smart double-network hydrogel (GS/DPPDH) with promising traits was developed by combining a dynamic Schiff base reaction between dialdehyde carboxymethyl cellulose (DCMC) and poly(ethylene imine) (PEI) with free radical polymerization. Because of its abundant amino groups, the common antibacterial drug gentamycin sulfate (GS) can be loaded into hydrogels by the formation of Schiff base bonds with DCMC. The slightly acidic wound microenvironment caused hydrolysis of the Schiff base bonds, thus releasing the drug GS on-demand. The prepared hydrogel not only showed good self-healing and injectable properties but also displayed excellent blood compatibility and cytocompatibility. The in vitro antibacterial experimental data proved that the GS/DPPDH had high antibacterial ratios of nearly 90% against both gram-positive (S. aureus) and gram-negative (E. coli) bacteria. In addition, in vivo assessment in a mouse model of S. aureus-infected full-thickness skin wounds revealed a wound closure ratio of 83.22 ± 2.90% after 7 days of healing, which was significantly greater than that in the gauze (59.78 ± 2.60%) and DPPDH (66.08 ± 0.21%) groups. Taken together, the results showed that the prepared antibacterial double-network hydrogel with injectable, self-healing, and pH-responsive properties exhibits great potential as a dressing material for infected wound healing. [ABSTRACT FROM AUTHOR]

Chronic skin wounds, especially infected ones, pose a significant clinical challenge due to their increasing incidence and poor outcomes. The deteriorative microenvironment in such wounds, characterized by reduced extracellular matrix, impaired angiogenesis, insufficient neurogenesis, and persistent bacterial infection, has prompted the exploration of novel therapeutic strategies. In this study, we developed an injectable multifunctional hydrogel (GEL/BG@Cu + Mg) incorporating Gelatin-Tannic acid/ N-hydroxysuccinimide functionalized polyethylene glycol and Bioactive glass doped with copper and magnesium ions to accelerate the healing of infected wounds. The GEL/BG@Cu + Mg hydrogel composite demonstrates good biocompatibility, degradability, and rapid formation of a protective barrier to stop bleeding. Synergistic bactericidal effects are achieved through the photothermal properties of BG@Cu + Mg and sustained copper ions release, with the latter further promoting angiogenesis. Furthermore, the hydrogel enhances neurogenesis by stimulating axons and Schwann cells in the wound bed through the beneficial effects of magnesium ions. Our results demonstrate that the designed novel multifunctional hydrogel holds tremendous promise for treating infected wounds and allowing regenerative neurogenesis at the wound site, which provides a viable alternative for further improving clinical outcomes. [Display omitted] • Multi-Functional Hydrogel-Bioactive Glass Dressing accelerate wound healing • The photothermal properties of BG@Cu + Mg boost the antibacterial effects • Copper ions released from Hydrogels enhance antibacterial and angiogenesis effects • Magnesium ions released from Hydrogels stimulate neurogenesis at the wound site [ABSTRACT FROM AUTHOR]

In hemodialysis, tunneled cuffed catheter (TCC) is commonly used as a medical device for establishing vascular access. To address the current problem that the skin tunnel of TCC is susceptible to bacterial infection, this work proposes quaternized modification of the cuff of TCC to comprehensively enhance the long‐lasting antimicrobial performance of TCC. The morphology of the cuff basically resembles the polyethylene terephthalate (PET). Via ultraviolet (UV) irradiation, acrylic acid (AA) was grafted onto PET. Then, amino polysaccharide quaternary ammonium salt (As) replaced H+ of the carboxyl groups on the macromolecular chain of PET through solution post‐treatment method. Through the single factor experiment, the degree of grafting reached 159.8% under the optimum preparation conditions (AA concentration of 25 vol%, H+ concentration of 0.2 mol/L, photosensitizer capacity of 15 wt%, and photo‐irradiation time of 30 min). By the above method, we successfully synthesized a highly hydrophilic, well biocompatible, and highly efficient antimicrobial PET‐g‐PAA@As. Animal experiments and histological analyses showed that PET‐g‐PAA@As was superior to PET control and blank control groups in controlling infection and promoting wound healing. This catheter material with excellent biocompatibility, sustained antimicrobial activity, and wound healing ability will have great potential for use in hemodialysis. [ABSTRACT FROM AUTHOR]

Biodegradable polymers can be utilized for coating plant derivations and help to preserve their medicinal properties, such as carboxymethyl cellulose (CMC). This study was conducted to investigate the wound healing activity of nanoemulsions (NEs) of Lavender officinalis essential oil (LOEO)/CMC in an infected mice model. Physicochemical properties of the NEs of LOEO and LOEO-NES/CMC-ONT were investigated. The NEs were blended with base formulations and administrated on infected wounds. Wound contraction, histopathological parameters, the expressions of CD31 and VEGF (Vascular endothelial growth factor), tumor necrosis factor-α (TNF-α), interleukin-6 (IL-6), smooth muscle alpha-actin (αSMA), transforming growth factor-β (TGF-β) and fibroblast growth factor-2 (FGF-2) were investigated. The results confirmed the successful synthesis and safety of the NEs. In addition, CMC helped to slow release and in a longer time of LOEO. Antibacterial activity of NEs and their ointment was confirmed. The results also showed that the administration of ointments prepared from LOEO-NEs/CMC and LOEO-NEs could increase the expression of CD31, VEGF, αSMA, TGF-β, FGF-2, and decrease TNF-α and IL-6 compared with mice treated with base formulations (p = 0.0001). Ointments prepared from LOEO-NEs/CMC and LOEO-NEs accelerate wound healing via promoting the proliferative phase and especially via factors involved in angiogenesis. [ABSTRACT FROM AUTHOR]

A sodium alginate/silk sericin (SA/SS) film was modified with glycerin (GI) and Polygonatum sibiricum polysaccharide@silver nanoparticles (PSP@AgNPs) to create a SA/SS/GI/PSP@AgNP composite film with antibacterial and antioxidant properties. The physicochemical properties of the SA/SS/GI/PSP@AgNP composite film were analyzed, and its cytocompatibility, antioxidant activity, and antibacterial properties were investigated. The optimum conditions for the preparation of the SA/SS/GI/PSP@AgNP composite film were 2 % SA, 2 % SS, 20 % GI, and 40 μg/mL of PSP@AgNPs. The addition of GI improved the surface smoothness of the composite films, while the presence of PSP@AgNPs did not significantly alter it. Spectroscopic characterization demonstrated that GI and PSP@AgNPs were physically bound to SA/SS. Approximately 53 % of the PSP@AgNP was released from the SA/SS/GI/PSP@AgNP composite film over 24 h of soaking in aqueous solution. The resulting leaching solution did not cause hemolysis or cytotoxicity, indicating its biocompatibility. Additionally, the SA/SS/GI/PSP@AgNP composite film exhibited strong antioxidant and antibacterial properties, and it promoted healing of mouse wounds infected with Staphylococcus aureus. [ABSTRACT FROM AUTHOR]

Nowadays developing wound dressing with higher antimicrobial properties which is accelerates healing, considered an emerging issue. In this study, we designed polylactic acid (PLA) films incorporated with different concentrations of nanochitosan (NCH), nanocellulose (CNC), and Trachyspermum ammi (Ajwain) essential oil (AEO) with in-vitro and in-vivo antimicrobial properties, for infected wound healing. In this study, AEO was extracted and the components were analyzed. The appearance, thickness, release of AEO, and the in-vitro antimicrobial properties of films were evaluated and the films with higher antimicrobial properties were used as dressing the wounds of rats. The mechanical properties of selected films with higher healing properties were analyzed. The results showed that thymol, P-cymene, and γ-terpinene were the main components of AEO. Also, all PLA films with AEO had antimicrobial properties, especially gram-positive bacteria. Finally, PLA films incorporated with 4 % NCH and 3 % AEO showed the highest antibacterial and wound healing properties. According to the results obtained in the tensile strength test, the PLA/NCH films had good strength and NCH improved the mechanical properties of the films. According to the results obtained in this study, the PLA films incorporated with NCH and AEO oil can be a suitable option for new wound dressings.

The current study was conducted to evaluate the effectiveness of geraniol nanophytosomes in accelerating the healing process of wounds infected with Methicillin-resistant Staphylococcus aureus (MRSA) in a mouse model. The physicochemical properties confirmed physical properties and successful synthesis of the nanophytosomes. Wounds were induced and mice (n = 90) were treated with a base ointment (negative control group) and/or mupirocin (positive control) and also formulations prepared from geraniol (GNL), geraniol nanophytosomes (NPhs-GNL), and PVA/NPhs-GNL. Wound contraction, total bacterial count, pathological parameters and the expressions of bFGF, CD31 and COL1A were also assessed. The results showed that topical administration of mupirocin and PVA/NPhs/GNL increased wound contraction, fibroblast and epithelization and also the expressions of bFGF, CD31 and COL1A while decreased the expression of total bacterial count and edema compared with negative control mice (P = 0.001). The results also showed that PVA/NPhs-GNL and mupirocin could compete and PVA/NPhs-GNL formulation was safe. In conclusion, the prepared formulations accelerated the wound healing process by modulation in proliferative genes. Geraniol nanophytosomes loaded into PVA could improve the healing in infected full-thickness wounds healing process and can be used for the treatment of infected wounds after future clinical studies. [Display omitted] • Geraniol was encapsulated into nanophytosomes (NPhs-GNL) by thin-layer hydration. • Nanophytosomes were successfully coated with polyvinyl alcohol (PVA/NPhs-GNL). • PVA/NPhs-GNL blending was prepared and characterized for the first time. • Topical PVA/NPhs-GNL led to reduce the tissue bacteria colonization and inflammation. • Topical PVA/NPhs-GNL led to increase the angiogenesis and COL1A expression. [ABSTRACT FROM AUTHOR]

Abstract Bacterial wound infections are a serious threat due to the emergence of antibiotic resistance. Herein, we report an innovative hybrid nanozyme independent of antibiotics for antimicrobial wound healing. The hybrid nanozymes are fabricated from ultra-small Au NPs via in-situ growth on metal-organic framework (MOF)-stabilised Fe3O4 NPs (Fe3O4@MOF@Au NPs, FMA NPs). The fabricated hybrid nanozymes displayed synergistic peroxidase (POD)-like activities. It showed a remarkable level of hydroxyl radicals (·OH) in the presence of a low dose of H2O2 (0.97 mM). Further, the hybrid FMA nanozymes exhibited excellent biocompatibility and favourable antibacterial effects against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The animal experiments indicated that the hybrid nanozymes promoted wound repair with adequate biosafety. Thus, the well-designed hybrid nanozymes represent a potential strategy for healing bacterial wound infections, without any toxic side effects, suggesting possible applications in antimicrobial therapy.

Damaged skin cannot prevent harmful bacteria from invading tissues, causing infected wounds or even severe tissue damage. In this study, we developed a controlled-release antibacterial composite hydrogel system that can promote wound angiogenesis and inhibit inflammation by sustained releasing Cu-Epigallocatechin-3-gallate (Cu-EGCG) nano-capsules. The prepared SilMA/HAMA/Cu-EGCG hydrogel showed an obvious inhibitory effect on Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). It could also promote the proliferation and migration of L929 fibroblasts. In vivo full-thickness infected wound healing experiments confirmed the angiogenesis and inflammation regulating effect. Accelerate collagen deposition and wound healing speed were also observed in the SilMA/HAMA/Cu-EGCG hydrogel treated group. The findings of this study show the great potential of this controlled-release antibacterial composite hydrogel in the application of chronic wound healing.

Bacterial wound infections are a serious threat due to the emergence of antibiotic resistance. Herein, we report an innovative hybrid nanozyme independent of antibiotics for antimicrobial wound healing. The hybrid nanozymes are fabricated from ultra-small Au NPs via in-situ growth on metal-organic framework (MOF)-stabilised Fe3O4 NPs (Fe3O4@MOF@Au NPs, FMA NPs). The fabricated hybrid nanozymes displayed synergistic peroxidase (POD)-like activities. It showed a remarkable level of hydroxyl radicals (·OH) in the presence of a low dose of H2O2 (0.97 mM). Further, the hybrid FMA nanozymes exhibited excellent biocompatibility and favourable antibacterial effects against both Gram-negative (Escherichia coli) and Gram-positive (Staphylococcus aureus) bacteria. The animal experiments indicated that the hybrid nanozymes promoted wound repair with adequate biosafety. Thus, the well-designed hybrid nanozymes represent a potential strategy for healing bacterial wound infections, without any toxic side effects, suggesting possible applications in antimicrobial therapy. [ABSTRACT FROM AUTHOR]

Bacteria infection is a significant obstacle in the clinical treatment of exposed wounds facing widespread pathogens. Herein, we report a DNA origami‐based bactericide for efficient anti‐infection therapy of infected wounds in vivo. In our design, abundant DNAzymes (G4/hemin) can be precisely organized on the DNA origami for controllable generation of reactive oxygen species (ROS) to break bacterial membranes. After the destruction of the membrane, broad‐spectrum antibiotic levofloxacin (LEV, loaded in the DNA origami through interaction with DNA duplex) can be easily delivered into the bacteria for successful sterilization. With the incorporation of DNA aptamer targeting bacterial peptidoglycan, the DNA origami‐based bactericide can achieve targeted and combined antibacterial therapy for efficiently promoting the healing of infected wounds. This tailored DNA origami‐based nanoplatform provides a new strategy for the treatment of infectious diseases in vivo. [ABSTRACT FROM AUTHOR]

It is of great importance to treat a bacterial-infected wound by a smart dressing capable of delivering antibiotics in a smart manner without causing drug resistance. The construction of smart release nanocontainers responsive to near-infrared (NIR) laser irradiation in an on-demand and stepwise way is a promising strategy for avoiding the emergence of multidrug-resistant bacteria. Here, we develop a hydrogel composite made of alginate and nanotubes with an efficient NIR-triggered release of rifampicin and outstanding antibacterial ability. This composite hydrogel is prepared through co-encapsulating antibacterial drug (rifampicin), NIR-absorbing dye (indocyanine green), and phase-change materials (a eutectic mixture of fatty acids) into halloysite nanotubes, followed by incorporation into alginate hydrogels, allowing the in-situ gelation at room temperature and maintaining the integrity of drug-loaded nanotubes. Among them, the eutectic mixture with a melting point of 39 °C serves as the biocompatible phase-change material to facilitate the NIR-triggered drug release. The resultant phase-change material gated-nanotubes exhibit a prominent photothermal efficiency with multistep drug release under laser irradiation. In an in vitro assay, composite hydrogel provides good antibacterial potency against Staphylococcus aureus, one of the most prevalent microorganisms of dangerous gas gangrene. A bacterial-infected rat full-thickness wound model demonstrates that the NIR-responsive composite hydrogel inhibits the bacteria colonization and suppresses the inflammatory response caused by bacteria, promoting angiogenesis and collagen deposition to accelerate wound regeneration. The NIR-responsive composite hydrogel has a great potential as an antibacterial wound dressing functionalized with controlled multistep treatment of the infected sites.

Treatment of infected wounds remains a challenge owing to antibiotic resistance; thus, developing smart biomaterials for the healing of infected wounds is urgently needed. In this study, a microneedle (MN) patch system with antimicrobial and immunomodulatory properties is developed to promote and accelerate infected wound healing. In the MN patch (termed PFG/M MNs), a nanoparticle with polydopamine (PDA)‐loaded iron oxide is grafted with glucose oxidase (GOx) and hyaluronic acid (HA) and then integrated into the tips, and amine‐modified mesoporous silica nanoparticles (AP‐MSNs) are incorporated into the bases. Results show that PFG/M MNs eradicate bacterial infections and modulate the immune microenvironment, combining the advantages of chemodynamic therapy, photothermal therapy, and M2 macrophage polarization from Fe/PDA@GOx@HA in the tips as well as anti‐inflammatory effect of AP‐MSNs from the MN bases. Thus, the PFG/M MN system is a promising clinical candidate for promoting infected wound healing. [ABSTRACT FROM AUTHOR]

Wound with drug‐resistant bacterial infections has become a serious challenge for the healthcare system, and designing wound dressing to self‐adapt to the need of different stage of wound healing remains challenging. Herein, self‐adaptive wound dressings with multiple stimuli‐responsiveness and antibacterial activity are developed. Specifically, MoS2 carrying a reactive oxygen species (ROS) responsive nitric oxide (NO) release precursor L‐arginine (MSPA) is designed and incorporated into carboxymethyl chitosan/poly(N‐isopropylacrylamide) based cryogels (CMCS/PNIPAM) with multiple responsiveness (pH, near infrared (NIR), and temperature) to form self‐adaptive antibacterial cryogels that adapt to the therapeutic needs of different stages in infected wound healing. In response to the slightly acidic environment of bacterial infection, the cryogels assist the bacterial capture capacity through acid‐triggered protonation behavior, and effectively enhance the photodynamic antibacterial efficiency. Controllable on‐demand delivery of ROS, NO, and remote management of infected biofluid are achieved with NIR light as a trigger switch. The multiple stimuli‐responsive nanozyme‐based cryogels efficiently eliminate MRSA bacterial biofilm through NO assisted photodynamicand photothermal therapy (PDT&PTT). The multiple enzyme‐like activities of the cryogels effectively relieved oxidative damage. Notably, these cryogels effectively reduce wound infection, alleviated oxidative stress, and accelerate collagen deposition and angiogenesis in infected wounds, indicating that multiple stimuli‐responsive self‐adaptive wound dressings provide new ideas for infected wound treatment. [ABSTRACT FROM AUTHOR]

Bio-adhesive polysaccharide-based hydrogels have attracted much attention in first-aid hemostasis and wound healing for excellent biocompatibility, antibacterial property and pro-healing bioactivity. Yet, the inadequate mechanical properties and bio-adhesion limit their applications. Herein, based on dynamic covalent bonds, photo-triggered covalent bonds and hydrogen bonds, multifunctional bio-adhesive hydrogels comprising modified carboxymethyl chitosan, modified sodium alginate and tannic acid are developed. Multi-crosslinking strategy endows hydrogels with improved strength and flexibility simultaneously. Owing to cohesion enhancement strategy and self-healing ability, considerable bio-adhesion is presented by the hydrogel with a maximal adhesion strength of 162.6 kPa, 12.3-fold that of commercial fibrin glue. Based on bio-adhesion and pro-coagulant activity (e.g., the stimulative aggregation and adhesion of erythrocytes and platelets), the hydrogel reveals superior hemostatic performance in rabbit liver injury model with blood loss of 0.32 g, only 54.2% of that in fibrin glue. The healing efficiency of hydrogel for infected wounds is markedly better than commercial EGF Gel and Ag+ Gel due to the enhanced antibacterial and antioxidant properties. Through the multi-crosslinking strategy, the hydrogels show enhanced mechanical properties, fabulous bio-adhesion, superior hemostatic performance and promoting healing ability, thereby have an appealing application value for the first-aid hemostasis and infected wound healing.

Wound treatment is largely influenced by pre-existing hypoxic microenvironments and biofilms, which can severely diminish the efficacy of phototherapy, suggesting the importance of multifunctional nanoplatforms for synergistic treatment of wound infections. Here, we developed a multifunctional injectable hydrogel (PSPG hydrogel) by loading photothermal sensitive sodium nitroprusside (SNP) into Pt-modified porphyrin metal organic framework (PCN) and in situ modification of gold particles to form a near-infrared (NIR) light-triggered all-in-one phototherapeutic nanoplatform. The Pt-modified nanoplatform exhibits a remarkable catalase-like behavior and promotes the continuous decomposition of endogenous H 2 O 2 into O 2 , thereby enhancing the photodynamic therapy (PDT) effect under hypoxia. Under dual NIR irradiation, PSPG hydrogel can not only produce hyperthermia (η=89.21%) but also generate reactive oxygen species and trigger NO release, contributing jointly to removal of biofilms and disruption of the cell membranes of methicillin-resistant Staphylococcus aureus (MRSA) and Escherichia coli (E. coli). In vivo experiments demonstrated a 99.9% reduction in bacterial burden on wounds. Additionally, PSPG hydrogel can accelerate MRSA-infected and Pseudomonas aeruginosa -infected (P. aeruginosa -infected) wound healing by promoting angiogenesis, collagen deposition, and suppressing inflammatory responses. Furthermore, in vitro and in vivo experiments revealed that PSPG hydrogel has good cytocompatibility. Overall, we proposed an antimicrobial strategy to eliminate bacteria through the synergistic effects of gas-photodynamic-photothermal killing, alleviating hypoxia in the bacterial infection microenvironment, and inhibiting biofilms, offering a new way against antimicrobial resistance and biofilm-associated infections. The NIR light-triggered multifunctional injectable hydrogel nanoplatform (PSPG hydrogel) based on Pt-decorated gold nanoparticles with sodium nitroprusside (SNP)-loading porphyrin metal organic framework (PCN) as inner templates can efficiently perform photothermal conversion (η=89.21%) to trigger NO release from SNP, while continuously regulating the hypoxic microenvironment at the bacterial infection site through Pt-induced self-oxygenation, achieving efficient sterilization and removal of biofilm by synergistic PDT and PTT phototherapy. In vivo and in vitro experiments demonstrated that the PSPG hydrogel has significant anti-biofilm, antibacterial, and inflammatory regulatory functions. This study proposed an antimicrobial strategy to eliminate bacteria through the synergistic effects of gas-photodynamic-photothermal killing, alleviating hypoxia in the bacterial infection microenvironment, and inhibiting biofilms. [Display omitted] [ABSTRACT FROM AUTHOR]

Abstract Treatment of infected wounds remains a challenge owing to antibiotic resistance; thus, developing smart biomaterials for the healing of infected wounds is urgently needed. In this study, a microneedle (MN) patch system with antimicrobial and immunomodulatory properties is developed to promote and accelerate infected wound healing. In the MN patch (termed PFG/M MNs), a nanoparticle with polydopamine (PDA)‐loaded iron oxide is grafted with glucose oxidase (GOx) and hyaluronic acid (HA) and then integrated into the tips, and amine‐modified mesoporous silica nanoparticles (AP‐MSNs) are incorporated into the bases. Results show that PFG/M MNs eradicate bacterial infections and modulate the immune microenvironment, combining the advantages of chemodynamic therapy, photothermal therapy, and M2 macrophage polarization from Fe/PDA@GOx@HA in the tips as well as anti‐inflammatory effect of AP‐MSNs from the MN bases. Thus, the PFG/M MN system is a promising clinical candidate for promoting infected wound healing.

Abstract Building a novel and efficient photothermal antibacterial nanoplatform is a promising strategy for precise bacterial elimination. Herein, a nanocomposite NiO NPs@AuNPs@Van (NAV) for selective MRSA removal was constructed by electrostatic self-assembly of highly photothermal magnetic NiO NPs and vancomycin (Van)-modified gold nanoparticles (AuNPs). In the presence of MRSA and under NIR irradiation, Van-mediated AuNPs can self-aggregate on MRSA surface, generating photothermal effect in situ and killing 99.6% MRSA in conjunction with magnetic NiO NPs. Additionally, the photothermal efficiency can be improved by magnetic enrichment due to the excellent magnetism of NAV, thereby enhancing the bactericidal effect at a lower experimental dose. In vitro antibacterial experiments and full-thickness skin wound healing test demonstrated that this combination therapy could effectively accelerate wound healing in MRSA-infected mice, increase collagen coverage, reduce IL-6 and TNF-α content, and upregulate VEGF expression. Biological safety experiments confirmed that NAV has good biocompatibility in vivo and in vitro. Overall, this work reveals a new type of nanocomposite with enhanced photothermal antibacterial activity as a potential nano-antibacterial agent for treating bacteria-infected wounds.

Skin wounds accompanied by massive bleeding and bacterial infection can be life-threatening and pose a significant challenge to clinical wound management. Herein, we prepared gellan gum/sericin hydrogels containing PDA-encapsulated halloysite nanotubes (halloysite@polydopamine) to achieve fast hemostasis and photothermally antibacterial effects. The morphology and compressive properties of the composite hydrogels were characterized, and the biocompatibility was investigated by hemocompatibility and cytocompatibility tests. The hemostatic properties were further evaluated in the rat liver hemorrhage and tail amputation model. The mechanical performance (compressive strength 353.2 KPa) and the hemostatic effect (30.33 ± 3.68 s in the liver injury model and 28.33 ± 2.35 s in the caudal amputation model) of the composite hydrogel were improved due to the introduction of halloysite@polydopamine. In addition, the composite hydrogel rapidly heated under 808 nm near-infrared (NIR) light irradiation, making the hydrogel extremely effective against E. coli and S. aureus. Furthermore, the wound closure rate, granulation tissue thickness, collagen deposition, and expression of inflammation-associated cytokines (CD68) and angiogenesis-associated cytokines (CD31) were investigated in a rat full-thickness skin defect model infected with S. aureus. All results showed that this multifunctional hydrogel provided better healing effects, suggesting that the composite hydrogel has become a promising alternative for infected wound repair.

Bacterial and biofilm infections are prevalent, photothermal antibacterial therapy exploiting Ag NPs was an alternative. However, various matrix materials including polysaccharides used to stabilize Ag NPs are not efficiently utilized. In this study, catechol functionalized quaternized chitin (DQC) is first synthesized, then Ag+ is in situ reduced to small Ag NPs stabilized and well-dispersed by DQC to form Ag NPs-incorporated quaternized chitin (DQCA) nanomicelle in a green and simple way. The photothermal conversion efficiency of the DQCA was up to be 65 %, which was much higher than that of many reported systems. The rationally designed DQCA takes full advantage of each component, specifically, DQCA is endowed with bacterial targeting, sterilization effects of cationic groups and Ag NPs, and superior photothermal combinational bactericidal and antibiofilm activities. The in vitro antibacterial rate of DQCA with NIR laser irradiation was >95 % in 10 min (99.5 % for E. coli and 95.7 % for S. aureus , respectively), and the eradication efficiency against both of the E. coli and S. aureus biofilms reached up to 99.9 %. Moreover, full-thickness S. aureus biofilms-infected wound healing test in the mouse model demonstrates that the combinational effect of DQCA nanomicelle could significantly accelerate the wound healing, by simultaneously reducing inflammation, enhancing re-epithelialization and promoting collagen deposition. And the wound treated with DQCA plus NIR irradiation at day 15 possessed the smallest open wound (2.5 %). Collectively, these features indicate facilely fabricated DQCA nanomicelle gets the most use of each component, and could serve as an excellent alternative for bacterial infection therapy. [ABSTRACT FROM AUTHOR]

[Display omitted] • A functional Zn-gallic acid nanozyme (Zn-NM) with excellent Antibacterial and ROS-scavenging capacity was fabricated. • Zn-NM nanozyme was loaded into a gelatin-based microneedle patch to achieve transdermal and sustained release of the drug. • The combination of nanozyme and microneedle patch is a synergetic therapy strategy for complicated infection wounds. Chronic bacterial-infected wound healing is becoming increasingly severe, with high rates of mortality and disability, owing to bacterial film, excessive accumulation of reactive oxygen species (ROS), inflammatory, and traditional therapeutics with poor drug permeability. Herin, a functional Zn-gallic acid nanozyme (Zn-NM) with excellent antibacterial and antioxidant capacity was incorporated with a gelatin-based microneedle patch (Zn-NM@MN) to achieve transdermal and sustained release of the drug at the infected wound site. The Zn-NM displayed the concentration-dependent antibacterial capacity, and 250 μg/mL of Zn-NM simultaneously possessed excellent antibacterial (89.36 ± 0.95 % for Escherichia coli, 92.44 ± 11.03 % for Staphylococcus aureus, and 95.03 ± 1.06 % for Methicillin-resistant Staphylococcus aureus), antioxidant properties and negligible cytotoxicity. After that, Zn-NM@MN could transdermal the epidermis or biofilm to sustain the release of Zn-NM for 3 h (release of 80 % drug). Systematic tissue regeneration assessment on rats' infected full-thickness skin wounds demonstrated an enhanced wound healing rate. Zn-NM@MN could efficiently kill the bacteria (about 85 %), alleviate oxidant stress, reduce bacterial-induced inflammation, and promote vascular regeneration. This synergetic therapy strategy will pave the way for treating complicated infection wounds. [ABSTRACT FROM AUTHOR]

The multi-drug resistance of methicillin-resistant Staphylococcus aureus (MRSA) and complex wound microenvironment challenge the repair of MRSA infected wound. Herein, in this study, α-tocopherol modified glycol chitosan (TG) nanoparticles encapsulated with phytochemical rhein (Rhein@TG NPs) were prepared for comprehensive anti-infection and promotion of MRSA infected wound healing. Rhein@TG NPs could not only specifically release rhein in the infection site in response to low pH and lipase of infectious microenvironment, but also up-regulated M1 macrophage polarization in the infection stage, thus achieving synergistically bacterial elimination with low possibility of developing resistance. Additionally, the NPs reduced the levels of pro-inflammatory factors in the post-infection stage, scavenged the ROS, promoted cell migration and angiogenesis, which significantly improved the microenvironment of infected wound healing. Therefore, this antibiotic-free NPs enabling anti-infection and promotion of wound healing provides a new and long-term strategy for the treatment of MRSA infected wound. [ABSTRACT FROM AUTHOR]

[Display omitted] • Multi-antibacterial through photothermal properties and Cu2+ release. • Temperature-responsive supramolecular hydrogel, stable at body temperature, dissociated at 50 °C. • Supramolecular hydrogel dressings removed with warm water. • Multifunctional hydrogel for the treatment of MRSA infected wounds. Antioxidant, antibacterial and removable supramolecular nanocomposite hydrogel dressings with self-healing and tissue adhesiveness is highly anticipated for bacterial infected skin wound healing. A series of supramolecular nanocomposite hydrogels via quadruple hydrogen bond and coordination bonds (catechol-Cu) was developed based on ureidopyrimidinone-modified poly(glycerol sebacate)–co-poly(ethylene glycol)-g-catechol (PEGSDU) and mesoporous copper sulfide nanoparticle (CuS NPs) as antioxidative, antibacterial, removable and tissue-adhesive dressing to treat the MRSA-infected wound. The hydrogels exhibited good self-healing, free radical scavenging, photothermal sterilization performance, adhesiveness, and temperature-sensitive removability. In addition, the Cu2+ was able to be slowly released from the hydrogel, which can promote the proliferation and migration of fibroblasts. Hydrogels containing CuS NPs showed better wound repair efficiency than commercial TegadermTM films and hydrogels without CuS NPs in MRSA-infected skin wound, which was attributed to the good antibacterial property, improved collagen deposition, reduced inflammatory response, and improved new vessels formation, thereby significantly promoting the repair of wounds. In summary, this antioxidative and antibacterial supramolecular nanocomposite hydrogel dressing provide a new type of multi-functional dressing for the treatment of infected skin wounds. [ABSTRACT FROM AUTHOR]

Fabricating injectable hydrogel with multiple functions and effective promotion of wound repair has a great prospect in treatment of bacterial infected wounds. Herein, a pH/reactive oxygen species (ROS) dual responsive injectable hydrogel (PVBDL-gel) was constructed, the PVBDL-gel was cross-linked by dynamic Schiff base bonds and borate ester bonds between poly(vanillin acrylate- co -3 acrylamide phenylboronic acid- co - N,N -dimethylacrylamide) (P(VA- co -AAPBA- co -DMA)), oligolysines and polyvinyl alcohol (PVA). The anti-inflammatory drug, dexamethasone sodium phosphate (DEX), was encapsulated in this hydrogel. The hydrogel exhibited excellent degradability, stable rheology and suitable tissue adhesion, more importantly, which showing pH/ROS responsive ability and controllable releasing of DEX. In vitro and in vivo experiment results showed that the PVBDL-gel with good biocompatibility and efficient anti-infection ability can effectively eradicate 99.9 % of pathogenic bacteria within 3 h and promote the repair and regeneration of bacterial infection wounds. This novel multifunctional injectable hydrogel has great application in the field of bacterial infection wound repair. • A pH/reactive oxygen species dual responsive injectable hydrogel was constructed. • The anti-inflammatory drug, dexamethasone sodium phosphate, was encapsulated in the hydrogel. • The hydrogel exhibited excellent degradability, stable rheology and suitable tissue adhesion. • Experiment results showed that the hydrogel with good biocompatibility and efficient anti-infection ability. • The hydrogel can effectively eradicate 99.9% of pathogenic bacteria within 3 h. [ABSTRACT FROM AUTHOR]

[Display omitted] • A "one-nano MOF-two-functions" strategy is proposed to prepare functional wound dressings. • Cur@Cu-MOF hydrogels have self-healing and co-delivery functions. • High antibacterial and anti-inflammatory properties are realized by the composite hydrogel. • Infected wound repair is enabled via promoted collagen deposition and angiogenesis. Porous metal–organic frameworks (MOF)-based hydrogels have recently attracted wide attention in sensing, catalysis, water treatment, and biomedicine. Yet, limited by challenges of insufficient stability, inordinate metal-ion leakage, and weak wound healing efficacy, the design of MOF-based hydrogel dressings for infected wounds has been rarely explored. Here, we propose a "one-nano MOF-two-functions" strategy to demonstrate the molecular engineering of a chemically stable nano MOF, which acts as both a carrier and a dynamic cross-linker, to fabricate functional composite hydrogels. The active amino groups of the MOF are employed to create dynamic networks with aldehyde-bearing alginate, ensuring excellent compatibility of the MOF with the polymer matrix and imparting effective self-healing properties to the resulting hydrogels. Simultaneously, two active ingredients, Cu nanoparticles (NPs) and curcumin, can be loaded into the nano MOF, achieving synergistic anti-inflammatory and antibacterial effects. Assisted by the mechanical stability and drug co-delivery in an infected full-thickness skin model, the MOF-based hydrogel can reduce the bacterial load on the wound by ∼103 times, and promote collagen deposition and angiogenesis by ∼1.5 and ∼3 times, compared with the control group. The "one-nano MOF-two-functions" design exhibits significant potential for high-performance infected wound dressings. [ABSTRACT FROM AUTHOR]

• High skin adaptability to avoid secondary tearing of wounds caused by sports. • Multimodal synergistic enhancement of antimicrobial properties. • Good biocompatibility and blood compatibility. • Effectively promote wound healing and tissue regeneration. Bacterial infection and inflammation hinder the natural healing process of skin wounds and may also cause wound complications. In light of the aforementioned considerations, this study developed an antibacterial and antioxidant QT/PDA@ZnO /QCS/(PAM-PAMPS) hydrogel (QPQH). The hydrogel dressing employs a dual network structure and incorporates quercetin (QT), quaternary ammonium salt chitosan (QCS), and polydopamine-coated zinc oxide nanoparticles (PDA@ZnO NPs) into a Polyacrylamide–Poly(2-acrylamido-2-methyl-1-propanesulfonic acid)（PAM-co-AMPS）hydrogel. This design enables QPQH to exhibit good mechanical properties, remarkable adhesion properties, and the capacity to adhere closely to the wound. The mild photothermal properties (˃50 °C) and Zn2+ release ability of PDA@ZnO NPs can cooperate with the destruction ability of QCS to bacterial cell membranes, thereby achieving efficient sterilization. This process has been demonstrated to be effective against Staphylococcus aureus and Escherichia coli , with approximately 98.5 % and 99.8 % efficiency, respectively. The incorporation of QT into hydrogel confers excellent antioxidant properties, which serve to reduce oxidative stress in wounds and prevent inflammation. Furthermore, hydrogel displays favorable blood compatibility and cell compatibility, facilitating the repair of bacteria-Infected wounds and promoting angiogenesis and collagen deposition in skin wounds. In conclusion, the antibacterial and antioxidant QPQH dressing has considerable potential for clinical use in the treatment of bacteria-Infected wounds. [ABSTRACT FROM AUTHOR]

Infected wound healing remains a significant issue in clinical medicine and has attracted wide attention in the field of biomedical engineering. Although a range of bioactive materials have been developed, few provide sufficient antibacterial and pro-angiogenic effects for effective wound healing. Herein, we constructed a series of nanofibers (termed PL-n, n = 0, 1, and 2) based on polycaprolactone (PCL), nanosilvers (AgNPs) and black phosphorus (BP) using electrospinning technology. The water contact angle of PL-n decreased significantly from 144.00 ± 1.00° for PL-0 to 0° for PL-2. The photothermal temperature increased significantly from 27.27 ± 0.25 °C for PL-0 to 40.7 ± 0.15 °C for PL-2. After exposure to near-infrared ray (NIR), the release rate of PL-2 increased from 78.00 ± 2.95 % to 89.46 ± 2.05 %. Biological experiments demonstrated that NIR-assisted PL-2 has excellent antibacterial and biofilm ablation activity with good biocompatibility. Furthermore, in vivo studies indicated that the NIR-assisted PL-2 accelerated wound healing by stimulating granulation tissue formation, collagen deposition, and angiogenesis and decreasing expression levels of CD68. The study suggests that this bi-functional nanofiber is indeed a versatile wound dressing, and is expected to be applied in clinical settings.

Antibiotic‐independent artificial nanozymes exhibit excellent biocatalytic activity, and can generate sufficient reactive oxygen species (ROS) for potential applications in the field of anti‐infective therapy. However, single nanozymes often catalyze the production of ROS with low yield and low utilization, resulting in low antibacterial activity. To address the above refractory concern, a spike‐like surface nanoparticles (CAC NPs) platform is built that possesses intrinsic dual enzyme‐like (oxidase and peroxidase‐like) activities and photothermal conversion capacity with near‐infrared irradiation (NIR‐I) to quickly capture and effectively eliminate the bacteria and biofilm. Upon NIR‐I irradiation, CAC NPs have exerted an excellent biocatalytic antibacterial effect through a hyperthermia‐amplified dual enzyme‐like activities strategy. As predicted, the results show CAC NPs can eradicate bacteria in the subcutaneous tissues of mice and promote the healing of inflamed tissues with no significant side effects in vivo. Collectively, this work reveals the potential of NIR‐assisted dual enzyme‐like activities for antimicrobial therapy and provides broad prospects for antimicrobial drugs and strategies. [ABSTRACT FROM AUTHOR]

Treating infected wounds is facing a serious challenge due to the rapid spread of antibiotic resistance worldwide. In the search for novel antimicrobial drugs, natural products often serve as a crucial resource. Plumbagin (PLB) is the most important natural active ingredient in the root of Plumbago zeylanica L. known for its excellent antibacterial ability. However, the application of PLB is limited because of its poor water solubility, instability, and tendency to sublimate. In this study, we propose a solution by designing a hyaluronic acid (HA)/polyvinylpyrrolidone (PVP) dissolving microneedle patch loaded with PLB/hydroxypropyl-β-cyclodextrin (HP-β-CD) inclusion complex. PLB was encapsulated into the cavity of HP-β-CD to improve its solubility and stability using the neutralization agitation method. The formation of the inclusion complex significantly increased the water solubility of PLB to 1350 ± 6.8 μg/mL, which is 17 times higher than its original value of 79.3 ± 1.7 μg/mL. The encapsulation efficiency was found to be 94.82 ± 3.34 %. In vitro drug release studies, PLB microneedles loaded with PLB/HP-β-CD inclusion complex rapidly released into PBS within 15 min. Furthermore, the PLB microneedles exhibited strong antibacterial activity against Staphylococcus aureus (S. aureus) both in vivo and in vitro. They also remarkably accelerated the healing of infected wounds in mice by enhancing collagen deposition and re-epithelialization, reducing inflammation, and stimulating angiogenesis. Overall, this multifunctional microneedle patch shows promising potential for clinical applications in the healing of infected wounds., Competing Interests: Declaration of Competing Interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024. Published by Elsevier B.V.)

Introduction: The photo-activated thermo/gas antimicrobial nanocomposite hydrogel, Gel/PDA@BNN6, is composed of the nitric oxide (NO) carrier N, N'-di-sec-butyl-N, N'-dinitroso-p-phenylenediamine (BNN6), photothermal (PTT) material polydopamine nanoparticles (PDA NPs), and methacrylate gelatin (GelMA). This hydrogel can release NO gas in a stable and controlled manner, generating a localized photothermal effect when exposed to near-infrared laser light. This dual action promotes the healing of full-thickness skin wounds that are infected., Methods: Gel/PDA@BNN6 was developed, and both in vitro and in vivo experiments were carried out to evaluate its structure, physicochemical properties, antibacterial effects, effectiveness in promoting infected wound healing, and biocompatibility., Results: Gel/PDA@BNN6 was successfully synthesized, exhibiting a porous three-dimensional lattice structure and excellent mechanical properties. It demonstrated highly efficient photothermal conversion, controllable nitric oxide delivery, strong bactericidal effects, and minimal cytotoxicity in vitro. In vivo, Gel/PDA@BNN6, when used with NIR therapy, showed significant anti-inflammatory effects, promoted collagen deposition, and stimulated vascular neoangiogenesis, which accelerated wound closure. Additionally, it displayed superior biocompatibility., Discussion: Gel/PDA@BNN6 has shown an explicit curative effect for infected wound healing, suggesting it has a good chance of being an antimicrobial dressing in the future., Competing Interests: The authors declare no conflict of interest., (© 2024 Yang et al.)

Generally, oligolysine has poor antibacterial effect and almost no antibacterial activity. Herein, low cost and easily available oligolysines were chosen to prepare injectable antibacterial hydrogel (PVAL-gel) for wound healing. The hydrogel network was formed by cross-linking vanillin acrylate-N, N-dimethylacrylamide copolymer P(VA-co-DMA), oligolysine and adipate dihydrazide through Schiff base bond. The obtained hydrogel PVAL-gel exhibited not only excellent self-healing capability and injectability, but also the efficient contact antibacterial ability and good inhibitory effects on E.coli and S.aureus. In vitro, 99.9 % of pathogenic bacteria was killed within 160 min. Furthermore, the injectable PVAL-gel could rapidly eradicate bacteria in infected wounds and notably enhance the healing of full-thickness skin wounds. Therefore, PVAL-gel is expected to be used as a high-end dressing for the treatment of infected skin wounds, which can promote wound healing., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2024 Elsevier B.V. All rights reserved.)

The delayed healing of infected wounds can be attributed to the increased production of reactive oxygen species (ROS) and consequent damages to vascellum and tissue, resulting in a hypoxic wound environment that further exacerbates inflammation. Current clinical treatments including hyperbaric oxygen therapy and antibiotic treatment fail to provide sustained oxygenation and drug-free resistance to infection. To propose a dynamic oxygen regulation strategy, this study develops a composite hydrogel with ROS-scavenging system and oxygen-releasing microspheres in the wound dressing. The hydrogel itself reduces cellular damage by removing ROS derived from immune cells. Simultaneously, the sustained release of oxygen from microspheres improves cell survival and migration in hypoxic environments, promoting angiogenesis and collagen regeneration. The combination of ROS scavenging and oxygenation enables the wound dressing to achieve drug-free anti-infection through activating immune modulation, inhibiting the secretion of pro-inflammatory cytokines interleukin-6, and promoting tissue regeneration in both acute and infected wounds of rat skins. Thus, the composite hydrogel dressing proposed in this work shows great potential for dynamic redox regulation of infected wounds and accelerates wound healing without drugs., (© 2024 Wiley‐VCH GmbH.)

The limited and unstable absorption of excess exudate is a major challenge during the healing of infected wounds. In this study, a highly stable, multifunctional Janus dressing with unidirectional exudate transfer capacity is fabricated based on a single poly(lactide caprolactone) (PLCL). The success of this method relies on an acid hydrolysis reaction that transforms PLCL fibers from hydrophobic to hydrophilic in situ. The resulting interfacial affinity between the hydrophilic/phobic PLCL fibers endows the Janus structure with excellent unidirectional liquid transfer and high structural stability against repeated stretching, bending, and twisting. Various other functions, including wound status detection, antibacterial, antioxidant, and anti-inflammatory properties, are also integrated into the dressing by incorporating phenol red and epigallocatechin gallate. An in vivo methicillin-resistant Staphylococcus aureus-infected wound model confirms that the Janus dressing, with the capability to remove exudate from the infected site, not only facilitates epithelialization and collagen deposition, but also ensures low inflammation and high angiogenesis, thus reaching an ideal closure rate up to 98.4% on day 14. The simple structure, multiple functions, and easy fabrication of the dressing may offer a promising strategy for treating chronic wounds, rooted in the challenges of bacterial infection, excessive exudate, and persistent inflammation., (© 2024 Wiley‐VCH GmbH.)

Infected wounds are a complex disease involving bacterial infections and dysregulated inflammation. However, current research has mostly focused on bacterial inhibition rather than on inflammation. Thus, combined therapeutic strategies with anti-bacterial and anti-inflammation efficacies are urgently needed. Antibiotics are the main treatment strategy for infections. However, the excessive use of antibiotics throughout the body can cause serious side effects. In addition, miRNA-based therapeutics are superior for the treatment of wounds, but their rapid degradation and poor cellular uptake limit their clinical application. Tetrahedral framework DNA (tFNA) is an ideal drug delivery system owing to its excellent stability and remarkable transport ability. Herein, a novel multi-functional miRNA and antibiotic co-delivery system based on tFNA is presented for the first time, called B/L. B/L has heightened resistance to serum and excellent codelivery ability. After transdermal administration, B/L can specifically target TNF receptor-associated factor 6(TRAF6) and IL-1receptor-associated kinase 1(IRAK1), thereby regulating nuclear factor kappa-B (NF-𝜿B) and thus effectively reducing inflammation and promoting the healing of infected wounds. This novel multi-functional co-delivery system provides a versatile, simple, biocompatible, and powerful platform for the personalized and combined treatment of multiple diseases., (© 2024 Wiley‐VCH GmbH.)

Postoperative wound of perianal infectious disease represents a common but unique refractory wound in clinical practice. The reasons that hinder the wound healing process include not only the severe bacterial infection of the wound itself and the narrow and deep shape of the wound, but also its frequent bacterial contact. Therefore, the development of biofunctional dressings to aid in therapy is essential. In this study, we synthesized a new type of dressing comprising a hydrogel host based on the Schiff base principle and catechol groups between polydopamine, oxidized dextran, and quaternized chitosan, and then loaded it with traditional Chinese medicine molecules. These formed an integrated hydrogel for accelerated wound repair in a perianal infection model. The prepared hydrogels exhibited excellent wet tissue adhesion, antifouling, morphological variability, suitable swelling properties, and complete degradability, as well as remarkable contact antibacterial ability and the ability to rapidly scavenge free radicals. Hemostatic experiments showed excellent hemostatic properties, as the integrated hydrogel could instantly gel to seal the hemorrhage. Hemocompatibility and in vitro cell experiments showed that the integrated hydrogel had good biosafety and significantly promoted cell proliferation, which in turn accelerated the repair of infected whole cortexes in rats. A histomorphological evaluation showed that the integrated hydrogel promoted the recovery of normal anatomical tissue in rats by promoting the formation of collagen fibers and inhibiting inflammation. The results showed that this multifunctional integrated hydrogel has great potential for the treatment of continuously infected skin regeneration, providing a promising therapeutic strategy for postoperative wound healing in perianal infectious diseases.

Building a novel and efficient photothermal antibacterial nanoplatform is a promising strategy for precise bacterial elimination. Herein, a nanocomposite NiO NPs@AuNPs@Van (NAV) for selective MRSA removal was constructed by electrostatic self-assembly of highly photothermal magnetic NiO NPs and vancomycin (Van)-modified gold nanoparticles (AuNPs). In the presence of MRSA and under NIR irradiation, Van-mediated AuNPs can self-aggregate on MRSA surface, generating photothermal effect in situ and killing 99.6% MRSA in conjunction with magnetic NiO NPs. Additionally, the photothermal efficiency can be improved by magnetic enrichment due to the excellent magnetism of NAV, thereby enhancing the bactericidal effect at a lower experimental dose. In vitro antibacterial experiments and full-thickness skin wound healing test demonstrated that this combination therapy could effectively accelerate wound healing in MRSA-infected mice, increase collagen coverage, reduce IL-6 and TNF-α content, and upregulate VEGF expression. Biological safety experiments confirmed that NAV has good biocompatibility in vivo and in vitro. Overall, this work reveals a new type of nanocomposite with enhanced photothermal antibacterial activity as a potential nano-antibacterial agent for treating bacteria-infected wounds. [ABSTRACT FROM AUTHOR]

The development of multifunctional wound dressings has always been considered as a promising strategy to promote blood coagulation, inhibit bacterial infection, and accelerate wound healing. Herein, an antibacterial and hemostatic dressing (SA-PHMG) was developed based on sodium alginate (SA) nonwoven and polyhexamethylene guanidine hydrochloride (PHMG) through a completely green industrial route, including dipping, padding, and drying. According to studies, SA-PHMG dressings exhibited excellent liquid absorption capacity and water vapor permeability. Moreover, bactericidal assays have demonstrated that SA-PHMG dressings have ideal antibacterial activity against Escherichia coli , Staphylococcus aureus , Pseudomonas aeruginosa and mixed bacteria, maintaining potent antibacterial activity even after 10 cycles of antibacterial trials or 50 times of washing or soaping. The in vitro evaluation of the hemostatic effect indicated that the SA-PHMG could significantly promote blood clotting by activating platelets, and in vitro and in vivo hemolysis, cytotoxicity and skin irritation studies demonstrated the ideal biocompatibility of the dressings. In addition, better wound closure and tissue regeneration were recorded using SA-PHMG nonwoven as the dressing based on an infected full-thickness wound model. In conclusion, this antibacterial, hemostatic, biocompatible, and environmentally friendly SA-PHMG nonwoven exhibit the potential for infected wound healing. [ABSTRACT FROM AUTHOR]

Background & Aims: In recent years, wound infections caused by Staphylococcus aureus have substantially grown. Lack of easy access, medications expensive, side effects, and in particular the development of drug resistance, the use of biological materials are proposed as an alternative solution. The recent study was aimed to evaluate the topical effect of Dianthus essential oil on cutaneous excisional wound healing in mice infected with S. aureus. Materials & Maethods: This study was performed on 36 mice (weight 25±3 g). After general anesthesia, 0.5 mm circle wound was created with biopsy punch between the shoulder, and immediately 50 γ of the suspension containing 107 CFU/ml S. Aureus was applied to the wound. Then tested animals, grouping in three groups of 12 mice each (control, treated with ointment 2% and 4%). During the project, image was obtained on days 3, 6, 9 and 12 images for assessment of wound area, and in 3, 7 and 14 from wounds in order to histopathology assessment. Results: The results of the wound size showed that the wound area decreased significantly in the treated groups (p< 0.05) compared with the control group. On histological examination, a significant (p< 0.05) reduction was observed in the migration of immune cells, the migration of fibroblasts and fibrocytes into the wound, the collagen synthesis and secretion. In addition, the thickness of the epithelium thickest increased in the treatment groups compared with the control group (p< 0.05). Conclusion: Based on the results of this study, topical application of Dianthus essential oil, especially at higher therapeutic doses, can be considered a viable option for treatment of infected wounds by the bacteria S. aureus.

[Display omitted] • Ag NPs enhance photocatalysis of MOFs and provide sites for bacteria-targeted groups. • MOFs@Ag-B@BBR shows efficient photo-anti bacterial activity against S.aureus and MRSA. • Released BBR and photo-anti bacterial reduce inflammation and promote wounds healing. Damaged skin is prone to recurrent bacterial infections, which hinder proper wound healing and exacerbate inflammation. Urgent attention is required to devise versatile dressings possessing antibacterial and anti-inflammatory attributes to facilitate wound recovery. In this study, we engineered a photo-responsive metal–organic frameworks (MOFs) gel, targeting bacteria, and endowed it with antibacterial and anti-inflammatory effects to address infected wound healing. On the one hand, the anionic MOF was choose to support cationic natural drug Berberine (BBR) to achieve slow release of anti-inflammatory drugs. On the other hand, the incorporation of Ag nanoparticles onto MOFs not only facilitates the generation of reactive oxygen species (ROS) via photocatalysis under visible light but also furnishes sites for boric acid group attachment to target bacteria and expedites ROS transfer. The resultant MOFs@Ag-B@BBR exhibited potent photodynamic antibacterial activity against Staphylococcus aureus and MRSA at a low concentration of 37.5 µg mL−1, surpassing the efficacy of most reported MOFs-based nano-antimicrobials. Upon application of the MOFs@Ag-B@BBR composite hydrogel to infected wounds, the released BBR, in conjunction with photodynamic antibacterial action, significantly mitigated inflammatory responses and fostered wound healing. This study provides a widely applicable approach for rational design of MOFs materials with enhance antibacterial and anti-inflammatory functions. [ABSTRACT FROM AUTHOR]