Excellent Adhesion Research Articles

Influence of Molybdenum Addition on the Structure, Mechanical Properties, and Cutting Performance of AlTiN Coatings

Though AlTiN coating has been intensively studied, there is still a need to develop AlTiN coating to meet the growing demand of industrial machining. One effective way to improve the performance of AlTiN coating is by adding alloying elements. In this study, AlTiN and AlTiMo coatings were deposited using multi-arc ion plating to investigate the influence of molybdenum addition on the structure, mechanical properties, and cutting performance of AlTiN coatings. Spherical droplets formed on the surfaces of both coatings, with the AlTiMoN coating exhibiting more surface defects than the AlTiN coating. The grazing incidence X-ray diffraction results revealed the formation of an (Al,Ti)N phase formed in the AlTiN and AlTiMoN coatings. Molybdenum doping in the AlTiMoN coating slightly reduced the grain size. Both coatings exhibited excellent adhesion to the substrate. The hardness (H), elastic moduli (E), H/E, and H3/E2 ratios of the AlTiMoN coating were higher than those of the AlTiN coating. The improvement in the mechanical properties was attributed to grain refinement and solution strengthening. Molybdenum doping improved the tribological properties and cutting performance of the AlTiN coatings, which was ascribed to the formation of MoO3 as a solid lubricant. These results show a path to increase the performance of AlTiN coating through molybdenum addition and provide ideas for the application of AlTiMoN coatings for cutting tools.

Isolation and in vitro investigation on lactic acid bacteria for potential probiotic properties from cat feces

BackgroundProbiotics, which are beneficial to the host, have been shown to benefit the health of cats. Lactic acid bacteria (LAB) are commonly used probiotics, but most strains used for cats are not derived from cats, leading to reduced efficacy and poor adaptation to cats. The objective was to identify LAB with promising probiotic potential specific to cats.MethodLABs were isolated from fecal samples of 20 healthy cats. Gram staining and the survival rate in the simulated gastrointestinal tract were used for preliminary screening. Candidate strains were identified by 16S rDNA sequencing, and further evaluated for adhesion ability, growth characteristics, antibacterial activity, antioxidant capacity, and safety.Results24 Gram-positive isolates were identified, with 10 (F1-F10) showing robust viability in the simulated gastroenteric fluid. These 10 strains exhibited excellent adhesion to Caco-2 cells and strong auto-agglutination properties. They also possessed the capacity to antagonize and aggregate pathogens (Staphylococcus aureus ATCC 25923, Salmonella Braenderup H9812, Escherichia coli ATCC 25922, and Pseudomonas aeruginosa PAO1), Moreover, all strains demonstrated tolerance to H2O2 concentrations ranging from 0.5–2 mmol/L and the ability to scavenge 1, 1-diphenyl-2-picrylhydrazyl (DPPH) free radicals, indicating a certain level of antioxidant activity. Safety tests showed no hemolytic activity, and all but F6 were highly sensitive to antibiotics, with over 62.5% sensitivity to 16 antibiotics. Remarkably, F4 (Lactobacillus reuteri) and F10 (Lactobacillus brevis) exhibited exceptional viability in the simulated gastrointestinal tract, coupled with robust growth potential, enhanced adhesion efficiency, significant antibacterial and antioxidant properties.ConclusionOur findings revealed that F4 (Lactobacillus reuteri) and F10 (Lactobacillus brevis) hold promising potential as probiotics. This research lays a solid scientific foundation for the selection and application of probiotics tailored specifically for cats.

Feasibility study of FFPP thermoplastic lining for concrete pipeline rehabilitation: a case study

This study investigates the feasibility and efficacy of Flexible Fiber-reinforced Polypropylene (FFPP) thermoplastic lining technology for the rehabilitation of concrete pipelines, specifically focusing on BONNA pipes. A custom-built test bench, featuring a 2-m high platform and multiple 90° bends, was designed to simulate the impact of pipe gallery space, adaptability and material accessibility of bent pipes, and cooling issues of long-distance dragging of materials. The simulation process utilizes a modified polyvinyl chloride (PVC) liner with unique thermomechanical properties. The liner, folded into an "H" shape, is mechanically inserted into the host pipe using a 2-ton winch and pulley system. During insertion, continuous high-temperature steam injection softens the material, facilitating expansion and conformity to the pipe's internal surface. Subsequently, cold air application rigidifies the liner below 60 °C while maintaining pressure, ensuring structural integrity and adherence to the pipe wall. Results revealed that while the FFPP liner successfully navigated through confined spaces, including a 300 mm expansion joint, spatial constraints led to localized cracking defects during inflation. Traction feasibility tests using a 2-ton winch demonstrated high pulling resistance in sections with multiple bends. The liner exhibited excellent adhesion in straight pipe sections but showed significant wrinkling and poor adhesion in 90° bends. Notably, the liner demonstrated remarkable strength, withstanding internal pressures exceeding 3.3 MPa in a DN300 pipe with a 10 cm diameter intentional defect, far surpassing the on-site hydrostatic test pressure of 9 bar. This study addresses a significant gap in trenchless rehabilitation research by evaluating the FFPP thermoplastic lining technique in complex pipeline geometries, an area previously understudied. While the technique shows promise for structural reinforcement in straight pipe sections, our findings reveal that its application in complex pipeline geometries requires further refinement. The study contributes to the field of trenchless pipeline rehabilitation in several ways: (1) it provides empirical data on FFPP liner performance in multi-bend configurations and confined spaces, (2) it identifies specific challenges such as localized cracking and poor adhesion in bends, and (3) it demonstrates the liner's exceptional strength under high pressure conditions. These insights advance our understanding of FFPP technology's potential and limitations in concrete pipe repair, paving the way for future research and development in optimizing trenchless rehabilitation techniques for complex pipeline systems.

A fabrication of universal multifunctional coating with excellent adhesion on the surface of solid rocket motor insulation materials through a surface activation strategy based on multiple interaction forces

In this work, a novel universal multifunctional coating for insulation materials was prepared by using polyethyleneimine as the coating substrate, low-temperature molten glass powders and MXene as additives. Meanwhile, the universal coating was tightly adhered to the surface of the insulation materials through a surface activation strategy based on the synergistic effects of hydrogen bonding, electrostatic adsorption, and chemical bonding. The shear strength data showed that the adhesion between the universal coating and the three types of insulation material were higher than that of most commercial adhesives. In the case of EPDM, for example, the adhesion of the coating is 4.17 (epoxy glue), 1.04 (chemlok) and 1.67 (Neoprene) times that of commercial adhesives, respectively. In addition, the universal coating showed good heat resistance and thermal insulation, and formed a complete and dense char on the surface after exposure to flame. The maximum mass loss temperatures of the three coated insulation materials were 2.8, 6.5, and 9.3°C higher than the original samples, respectively. Thermal insulation tests showed that the coated insulation materials reduced the average top surface temperature by 29.68%, 40.84% and 29.06%, respectively, compared to the original samples. The results of anti-migration tests showed that the prepared universal coatings displayed generally superior anti-migration properties to the insulation materials, with equilibrium migration concentrations reduced by up to more than 80% compared to the original samples, which is better than the previous products of the same type. In addition, the application potential of the advanced multifunctional insulation materials obtained from the preparation was evaluated, resulting in an increase of more than 35% in peel strength and more than 20% in shear strength for all insulation materials with propellants. This work provides a simple and environmentally friendly generalized strategy to develop high performance insulation materials for aerospace fields.

Cellulose nanocrystals-based Pickering emulsion with enhanced foliar adhesion and pH responsiveness for intelligent delivery of pesticides

Pickering emulsions stabilized by functionalized natural macromolecules have emerged with promising responsiveness for pesticide encapsulation and release. This study developed Pickering emulsions using amine-modified cellulose nanocrystals (ACNCs) as stabilizers. The resultant O/W ACNCs-Pickering emulsions (ACNCs-Pickering) exhibited long-term storage stability and showed increasing emulsion stability depending on the concentration of ACNCs. Imidacloprid (IMI) was subsequently loaded onto the ACNCs-Pickering to form the IMI@ACNCs-Pickering via the in-situ loading route. The release rate of IMI demonstrated a notable pH responsiveness. Moreover, the IMI@ACNCs-Pickering prepared with an ACNCs concentration of 3 wt% showed optimal performances. Its foliar adhesion on Chinese cabbage (Brassica rapa L.ssp.pekinensis) was significantly higher than that of the commercial IMI formulation (70 WS, Bayer®, LS200032) (DG). In detail, the pesticide residue for the IMI@ACNCs-Pickering was 3.8 folds to that for DG after spraying and washing for 10 min. Also, the green peach aphid mortality rate was 98.33 %, which was 1.1 folds higher than that of the DG group. The present work developed a Pickering emulsion-based fat-soluble pesticide formulation with excellent foliar adhesion, resistance to rainfall washout, and insecticidal effect. It provided a new option to ensure the sustainable development of green agriculture.

Environment-tolerant, inherently conductive and self-adhesive gelatin-based supramolecular eutectogel for flexible sensor

Although hydrogels have attracted increasing attention in the stretchable devices, the low adhesion properties and poor environmental adaptation still seriously restrict their development and application. Herein, we focused on the interaction between polymer networks with disperse media and their resultant influence on gel performance, and constructed self-adhesive and environment-tolerant gelatin/polyacrylamide supramolecular-polymer double-network (Gelatin/PAM SP-DN) eutectogels using multiple supramolecular interactions between natural macromolecule and well-designed deep eutectic solvent (DES). The dual networks of Gelatin/PAM SP-DN eutectogels produced significant supramolecular forces with DES, including hydrogen bonding and electrostatic interaction, contributing to enhance the energy dissipation capacity. Additionally, the Gelatin-PAM SP-DN eutectogels were more prone to generate strong bonding force to various substrates, showcasing both in-situ and ex-situ adhesion performance, and even being used for wet and underwater adhesion. The eutectogels revealed excellent environmental tolerance to maintain excellent mechanical flexibility, conductivity and adhesion at high and low temperatures, ensuring the constructed sensor to sensitively and reliably perceive strain, pressure and human motions over a wide temperature range. Also, the eutectogel demonstrated great potential as a temperature sensor. This work opens up a new horizon in the design of multifunctional and environment-tolerant natural macromolecule-based gel materials for flexible electronics, human-machine interaction and health diagnosis.

Dual-functionalized ORMOSIL nanoparticles to enhance superhydrophobicity of epoxy based coatings

Organically modified silica (ORMOSIL) nanoparticles bearing fluoro-octyl and glycidoxy-propyl groups were prepared by two simple methods: i) modification of silica (SiO2) nanoparticles with the corresponding organo-silanes and ii) sol-gel process involving tetraethoxy-silane in the presence of the organo-silanes. These hydrophobic ORMOSIL particles were mixed with epoxy resin/amino-based hardener in 2-propanol medium and sprayed on the surface of carbon-steel substrate. The epoxy coating containing ORMOSIL prepared by modification of SiO2 nanoparticle presented outstanding water repellence with water contact angle (WCA) of ≈ 162° and high roll-off ability of the water droplets. Furthermore, excellent adhesion to the substrate was evidenced by sandpaper abrasion and tape peeling test. The effect of the solid content in the 2-propanol dispersion on the superhydrophobicity character was investigated. It was observed that the spray dispersion with higher solid concentration resulted in better superhydrophobicity response, mechanical durability and effective self-cleaning behavior. The hierarchical structure and roughness were identified by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The coatings presented in this work are strong candidates for large scale production due to the low-cost and simplicity of the spraying technique and the economically feasibility of the involved compounds.

High strength lignocellulose derived epoxy adhesive with heat and acid-base resistance

In this work, we developed a high-performance two-component epoxy adhesive from two biobased triple-functional and hexa-functional epoxy monomer from lignin-derived monomer eugenol, and a cellulose-derived furfuryl diamine for metal substrates. Through a tight cross-linked network and rich electronegative structure, the adhesives showed excellent adhesive performance to various metal substrates, especially for Fe. It demonstrated a high lap shear strength up to 19.8 MPa to Fe substrate, surpassing most reported epoxy adhesives. Moreover, these adhesives exhibited excellent long-term adhesion properties in high-temperature and acidic/base aqueous environments. It can maintain more than 95% of the adhesive strength to Fe substrate after soaking in different acid-base environments for 7 days, and achieved a maximum adhesion strength of 16.46 MPa to Fe substrates at 200 °C only 14.2% decrease when compared to that at room temperature. Molecular simulations revealed that these two adhesives could rapidly achieve dynamic equilibrium with Fe (110) surface in 15 and 22 ps which was much shorter than that to Cu and Al, suggesting a stronger binding energy between these adhesive and Fe surfaces and was consistent with the adhesion performance. This work widens the way for high-performance bio-based epoxy adhesives to be used in more demanding environments.

Neurotensin Conjugated Polymeric Porous Microparticles Suppress Inflammation and Improve Angiogenesis Aiding in Diabetic Wound Healing.

Neurotensin (NT), a bioactive tridecapeptide aids in diabetic wound healing by modulating inflammation and angiogenesis. However, its rapid degradation in peptidase-rich wound environment (plasma half-life <2 min) limits its efficacy. To address this, neurotensin-conjugated polymeric porous microparticles (NT-PMP) were developed and loaded in gelatin (hydrogel 15% w/v) for topical application, enabling sustained NT release to enhance therapeutic outcomes. NT-PMP exhibited a size range of 60 - 240 µm (mean: 120.63 ± 40.71 µm) and pore size of 5 - 16 µm (average: 10.68 ± 3.47 µm). In vitro studies demonstrated cytocompatibility of NT-PMP in fibroblasts and reduced TNF-α levels in inflammation-induced macrophages (1256 ± 167.02 pg/ml). Further NT-PMP scaffold depicted excellent cell adhesion and migration properties upon seeding of dermal fibroblasts on surface of PMPs. In vivo studies in diabetic wound rat model demonstrated effective wound management, characterized by notable regenerative and healing attributes in the presence of NT-PMP. This included complete re-epithelialization, reducing pro-inflammatory cytokine (TNF-α), and enhancing VEGF expression, ultimately leading to the development of a well-organized collagen matrix in diabetic wounds upon application of NT-PMP gel.Altogether, NT conjugated PMP loaded in hydrogel demonstrated significant regenerative and healing properties, suggesting its potential as an alternative treatment for diabetic wounds.

Polyelectrolyte complex coatings based on PSS/CTAB for enhanced antifogging and antibacterial performances

Antifogging and antibacterial properties are both essential in biomedical examination and diagnostics to ensure clear visibility and prevent potential bacterial infections. However, it is extremely challenging to integrate both functions on one surface. Herein, this study presents a rapidly assembled polyelectrolyte complex (PEC) coating, which can be applied to different transparent substrates through a facile combination of anionic polystyrene sulfonic acid (PSS) and cationic surfactant cetyltrimethylammonium bromide (CTAB). Unlike traditional superhydrophilic anti-fogging mechanisms, this coating leverages the hygroscopic properties of polyelectrolyte complex groups, ensuring effective anti-fogging performances across a wide temperature range. Additionally, the incorporation of quaternary ammonium compounds (QACs) within the PEC complex confers strong bactericidal properties to the coating. The resultant coating exhibits excellent surface adhesion and robust resistance to water immersion, and low cytotoxicity. With its dual antifogging and antibacterial properties, this coating shows significant promise for diverse applications in medical diagnostic and detection lens equipment.

High-reliable polyurethane modified epoxy photosensitive composites for solder resist applications

Developing solder resist ink (SR) with superior comprehensive performance through the chemical modification of epoxy resin (EP) using polyurethane oligomers (PU) is an effective strategy. In this study, a highly reliable SR was designed by chemically grafting -NCO terminated PU onto the -OH groups of the EP molecular chain. By adjusting the PU content, high flexibility, reliability, and adhesion of the EP-PU system were achieved. Compared to SR-0, when the PU content is 50 % of EP, under conditions of 85 % humidity, 130 °C temperature, and 1 V voltage, the failure time of SR-0.5 can be adjusted from 67.5 h to over 150 h, an increase of 150 %. This high-reliability characteristic makes it potentially useful in applications such as printed circuit board and packaging substrate manufacturing. Additionally, by adjusting the PU content in the EP-PU system, the degree of crosslinking in the EP-PU molecular chain can be controlled, resulting in excellent adhesion, alkali resistance, hydrophobicity, mechanical properties, low water absorption, and good thermal stability. The chemical modification of EP with PU provides a theoretical basis and technical support for the development of high-performance SR, while also offering more reliable material solutions for the advancement of the electronics industry.

Recent Progress on Advanced Flexible Lithium Battery Materials and Fabrication Process.

Flexible energy storage devices have attracted wide attention as a key technology restricting the vigorous development of wearable electronic products. However, the practical application of flexible batteries faces great challenges, including the lack of good mechanical toughness of battery component materials and excellent adhesion between components, resulting in battery performance degradation or failure when subjected to different types of deformation. It is imperative to develop flexible batteries that can withstand deformation under different conditions and maintain stable battery performance. This paper reviews the latest research progress of flexible lithium batteries, from the research and development of new flexible battery materials, advanced preparation processes, and typical flexible structure design. First, the types of key component materials and corresponding modification technologies for flexible batteries are emphasized, mainly including carbon-based materials with flexibility, lithium anode materials, and solid-state electrolyte materials. In addition, the application of typical flexible structural designs (buckling, spiral, and origami) in flexible batteries is clarified, such as 3D printing and electrospinning, as well as advanced fabrication techniques commonly used in flexible materials and battery components. Finally, the limitations and coping strategies in the practical application of flexible lithium batteries are discussed, which provides new ideas for future research.

Adaptable Hydrogel with Strong Adhesion of Wet Tissue for Long-Term Protection of Periodontitis Wound.

Periodontitis is a severe gum infection characterized by inflammation of the tissues surrounding the teeth. The disease is challenging to manage due to its exposure to a wet and dynamic oral environment, where conventional hydrogels often suffer from weak adhesion, short residence time, and vulnerability to bacterial invasion. In this study, an innovative hydrogel system based on in situ light curing is proposed. The hydrogel precursor, comprising sodium alginate and a calcium ion network, is designed and adhere to the irregular and smooth surfaces of periodontal tissue before curing. Upon light irradiation, a second network polymerizes rapidly, establishing multiple interactions with the tissue, which enhances adhesion strength. Benefited from this engineering strategy, the hydrogelexhibits a low swelling rate, effectively mitigating adhesion loss in the moist oral environment. Additionally, the hydrogel demonstrates excellent long-lasting wet adhesion, maintaining its presence in periodontal tissue over 120 hours. It also serves as an effective physical barrier against bacterial invasion, achieving a blocking efficiency of 99.9%. This novel design concept offers a promising approach for developing advanced medical dressings for periodontitis, providing sustained therapeutic benefits.

Injectable and adhesive MgO2-potentiated hydrogel with sequential tumor synergistic therapy and osteogenesis for challenging postsurgical osteosarcoma treatment

The clinical treatment of osteosarcoma faces great challenges of residual tumor cells leading to tumor recurrence and irregular bone defects difficult to repair after surgery removal of the primary tumor tissue. We developed an injectable and in-situ cross-linkable hydrogel (named MOG hydrogel) using MgO2 nanoparticles and dopamine-conjugated gelatin as main components. MgO2 was rationally designed as a multifunctional active ingredient to mediate in situ gelation, tumor therapy, and bone repair sequentially. The 10MOG (with 10 mg/mL MgO2 content) showed excellent gel stability, injectability, shape adaptability, tissue adhesion, and rapid hemostatic ability. Importantly, 10MOG exhibited ideal sequential H2O2 and Mg2+ release property. The released H2O2 synergized with photothermal therapy for enhanced tumor recurrence suppression, and the sustainable Mg2+ release efficiently promoted bone regeneration. The MOG hydrogel, possessing excellent on-demand antitumor and osteogenic capabilities in vitro and in vivo, exhibited tremendous potential in the clinical application for challenging postsurgical osteosarcoma treatment.

Improvement and Recovery of Intestinal Flora Disorder Caused by Ciprofloxacin Using Lactic Acid Bacteria.

In this study, four lactic acid bacteria (LAB) strains demonstrating ciprofloxacin, bile salt, gastric fluid, and intestinal fluid tolerance as well as adhesion ability to Caco-2 and HT-29 cells were used to improve and recover the intestinal flora disorders caused by ciprofloxacin, among which, Lactobacillus brevis 505 exhibited excellent adhesion ability to two kinds of cells and colonization ability to mouse intestinal. After ciprofloxacin treatment, certain recovery effect on cecum caused by ciprofloxacin in the mice was found during natural recovery (group 5C2), but it was challenging to fully restore the intestinal integrity to the initial level. After L. brevis 505 intervention (group 5C5), the intestinal damage to the colon and ileum caused by ciprofloxacin in mice was significantly alleviated; the recovery effect was better than that of natural recovery. Additionally, L. brevis 505 could effectively regulate INF-γ, sIgA, and RegIIIγ increase induced by ciprofloxacin. Shannon and Simpson index of the intestinal flora of mice in 5C5 group were higher than those in other group, the relative abundance of Bifidobacterium and Lactobacillus in the mice in 5C5 group was increased, indicating that LAB can better restore the structure and abundance of intestinal microflora. Consequently, L. brevis 505 shows promise as a probiotic for gut microbiota restoration and rebuilding during antibiotic therapy.

Preparation and Properties of Thick Tungsten Coating Electrodeposited from Na2WO4-WO3-KCl-NaF Molten Salt System

The pulsed current electrodeposition method was employed for the first time to achieve tungsten coating with a thickness of 433.72 μm on a CuCrZr alloy from Na2WO4-WO3-KCl-NaF molten salt. The microstructure of the coating was observed and the coating density, porosity, hardness, bonding strength, residual stress and oxygen content were tested. The results revealed that the tungsten coating exhibited desirable characteristics such as high density, absence of impurities, excellent adhesion to the matrix (53.16 MPa), residual compressive stress as surface stress, and good stability and durability. Moreover, this thick tungsten coating possesses high density and hardness, low oxygen content and porosity. This offers a novel solution to solve the challenging issue of the connection between tungsten material and heat sink material.

Inverse Vulcanization of Aziridines: Enhancing Polysulfides for Superior Mechanical Strength and Adhesive Performance

This study introduces a novel approach to inverse vulcanization by utilizing a commercially available triaziridine crosslinker as an alternative to conventional olefin‐based crosslinkers. The model reactions reveal a self‐catalyzed ring‐opening of "unactivated" aziridine with elemental sulfur, forming oligosulfide‐functionalized diamines. The triaziridine‐derived polysulfides exhibit impressive mechanical properties, achieving a maximum stress of ~8.3 MPa and an elongation at break of ~107%. The incorporation of silicon dioxide (20 wt%) enhances the composite’s rigidity, yielding a Young's modulus of ~0.94 GPa. Furthermore, these polysulfides display excellent adhesion strength on various substrates, such as aluminum (~7.0 MPa), walnut (~9.6 MPa), and steel (~11.0 MPa), with substantial retention of adhesion strength (~3.3 MPa on steel) at −196 °C. The straightforward synthetic process, combined with the accessibility of the triaziridine crosslinker, emphasizes the potential for further innovations in sulfur polymer chemistry.

Inverse Vulcanization of Aziridines: Enhancing Polysulfides for Superior Mechanical Strength and Adhesive Performance.

This study introduces a novel approach to inverse vulcanization by utilizing a commercially available triaziridine crosslinker as an alternative to conventional olefin-based crosslinkers. The model reactions reveal a self-catalyzed ring-opening of "unactivated" aziridine with elemental sulfur, forming oligosulfide-functionalized diamines. The triaziridine-derived polysulfides exhibit impressive mechanical properties, achieving a maximum stress of ~8.3 MPa and an elongation at break of ~107%. The incorporation of silicon dioxide (20 wt%) enhances the composite's rigidity, yielding a Young's modulus of ~0.94 GPa. Furthermore, these polysulfides display excellent adhesion strength on various substrates, such as aluminum (~7.0 MPa), walnut (~9.6 MPa), and steel (~11.0 MPa), with substantial retention of adhesion strength (~3.3 MPa on steel) at -196 °C. The straightforward synthetic process, combined with the accessibility of the triaziridine crosslinker, emphasizes the potential for further innovations in sulfur polymer chemistry.

Anti-Inflammatory Effects of Novel Probiotic Lactobacillus rhamnosus RL-H3-005 and Pedicoccus acidilactici RP-H3-006: In Vivo and In Vitro Evidence.

Probiotics have garnered escalating attention in the treatment and prevention of inflammatory disorders. In this study, Lactobacillus rhamnosus RL-H3-005 (RL5) and Pediococcus acidilactici RP-H3-006 (RP6), which possess anti-inflammatory effects and favorable probiotic attributes, were selected through the comparison of an RAW264.7 inflammatory cell model screening and in vitro probiotic properties. Subsequently, it was implemented in an animal model of dextran sulfate sodium (DSS)-induced colitis. The results demonstrated that RL5 and RP6 could inhibit the release of proinflammatory factors in RAW264.7 inflammatory cells and exhibited excellent environmental adaptability, adhesion, safety, and antibacterial activity. Additionally, RL5 and RP6 provided protective effects on the intestines of mice with acute colitis by reducing the levels of intestinal inflammation and oxidative stress. Concurrently, supplementation with RL5 and RP6 modulated the composition of the gut microbiota in mice. These discoveries suggest that RL5 and RP6 can be used as a novel probiotic for alleviating intestinal inflammation.

Antioxidative hydrogel based on hyaluronic acid/polyethylene glycol loaded with shikonin-coated flexible liposome and evaluation of its therapeutic effect on eczema

Eczema, a common skin condition, is gaining attention due to its increasing annual prevalence and severe influence on both bodily and mental health. Existing treatments for this disease often have significant side effects and safety concerns. Comfrey, a traditional Chinese herbal remedy, is commonly used to treat skin conditions. Shikonin, the primary active compound in comfrey, has demonstrated efficacy in treating eczema. Herein, a flexible liposome-containing SHI was dispersed in hydrogels based on hyaluronic acid (HA) and polyethylene glycol(PEG) for the treatment of eczema. The hydrogel performed well in delaying drug release. SHI-F-Gel demonstrated notable antioxidant properties, effectively eliminating over 80 % of free radicals. Compared to the SHI solution, SHI-F-Gel significantly increased drug skin retention by 312.9 %. In animal studies, SHI-F-Gel administration reduced epidermal thickness in the affected area by approximately 36.8 % and increased collagen deposition by 90.23 %. Additionally, SHI-F-Gel inhibited the expression of pro-inflammatory cytokines interleukin-4 (IL-4) and IL-17. This observed reduction in inflammation suggests that the treatment is effective. In conclusion, the flexible SHI-based liposome hydrogel demonstrates excellent adhesion and biocompatibility, making it a promising candidate for enhancing eczema treatment.