Metal-phenolic Network Research Articles

Fabrication of Novel Porous Nano-pesticides by Modifying MPN onto Cu-TCPP MOFs to Enhance Bactericidal Efficacy and Modulate Its Bioavailability.

Nano-pesticides have attracted much attention in the field of agriculture, due to existing problems such as decreased bactericidal effect and poor adhesion. An environmentally friendly metal porphyrin (Cu-TCPP)-based nanocarrier pesticide release of diniconazole (DIN) was designed to enhance bactericidal efficacy and modulate its bioavailability in a multidimensional manner by constructing a metal phenolic network (MPN) encapsulation. The introduction of the MPN prevents the DIN from prematurely escaping from the Cu-TCPP@DIN@MPN in the environment and gives it strong interfacial adhesion to resist rain washing. The resulting Cu-TCPP@DIN@MPN nanoparticles (NPs) showed a lamellar stacked embedded structure, which improved the inhibition of Fusarium oxysporum (90.9%) and photostability (67.2%), while they do not affect healthy plant growth and meet the relevant food safety requirements for DIN residues. This work provides new ideas for the development of superior photostable, adhesive, rainwater erosion-resistant, and sustainable nanocarrier pesticides.

Development and preservative applications of polysaccharide-based bilayer packaging films: Enhanced functional properties through metal-phenolic network-coated zein nanoparticles and biomimetic hydrophobic surfaces

This study develops an innovative bilayer biomimetic hydrophobic film, tailored to provide a sustainable and eco-friendly packaging solution for fresh produce. The outer layer, crafted from chitosan, utilized polydimethylsiloxane templating to mimic the ultra-hydrophobic surface of a lotus leaf, achieving a water contact angle exceeding 130°. The inner layer comprised sodium alginate and zein nanoparticles, enriched with citral and fortified by a metal-phenolic network to facilitate uniform dispersion and controlled release of bioactive agents. The structural design of the film significantly improved mechanical properties, evidenced by a maximum tensile strength of 29.3 ± 3.6 MPa, and enhanced hydrophobicity, reducing water solubility to 28.3 ± 1.5% and substantially decreasing water absorption. The barrier functionality of film was also strengthened, demonstrated by a lowered water vapor transmission rate of 289.3 ± 1.5 g m−2 24 h−1, and it supported extended citral release in acidic media up to 70 h. Moreover, the film exhibited robust antioxidant and antibacterial properties. In practical tests, it effectively mitigated weight loss, browning, and hardness degradation in fresh-cut apples and lotus roots, concurrently inhibiting microbial growth and extending shelf life. This study presents an effective strategy for enhancing the hydrophobicity and bioactivity of bio-based films, contributing valuable insights to the field of sustainable food packaging.

Metal-phenolic network crosslinked nanogel with prolonged biofilm retention for dihydroartemisinin/NIR synergistically enhanced chemodynamic therapy

Chemodynamic therapy (CDT) is emerging as a promising treatment for biofilm infections. However, its effectiveness is significantly hindered by several factors: the body’s stable temperature, a limited supply of Fe2+ ions, and inadequate endogenous levels of H2O2 at the infection sites. Herin, our study introduces MPN-crosslinked hyaluronic acid (HA) nanogels as an effective strategy for treating biofilm-associated infections. The DHA@HA-TA/Fe (DHTF) nanogel is synthesized through the coordination reaction between Fe2+ ions and tannic acid (TA)-modified HA, with dihydroartemisinin (DHA) encapsulated within the structure. DHTF exhibits pH-/hyaluronidase-responsiveness in the biofilm infection microenvironment, enabling sustained release of DHA as a substitute for H2O2 and Fe2+ for CDT. The incorporation of Fe2+/TA-based MPN and DHA within the nanogels enables photothermal/DHA dually-enhanced CDT, facilitating efficient disruption of biofilm matrices and bacterial eradication through boosting reactive oxygen species production. In vivo studies demonstrate that DHTF exhibit prolonged retention within biofilms. This ensures a sustained release of therapeutic agents and continuous anti-biofilm activity. Eventually, both in vitro and in vivo evaluations consistently confirm the significant anti-biofilm capacity of DHTF. Our findings highlight the potential of DHTF as a promising nanomedicine for biofilm-related infections, offering efficient treatment strategies that could improve clinical management of these challenging conditions.

Hybrid nanoparticle-mediated simultaneous ROS scavenging and STING activation improve the antitumor immunity of in situ vaccines.

In situ vaccine (ISV) is a versatile and personalized local immunotherapeutic strategy. However, the compromised viability and function of dendritic cells (DCs) in a tumor microenvironment (TME) largely limit the therapeutic efficacy. We designed a hybrid nanoparticle-based ISV, which accomplished superior cancer immunotherapy via simultaneously scavenging reactive oxygen species (ROS) and activating the stimulator of interferon genes (STING) pathway in DCs. This ISV was constructed by encapsulating a chemodrug, SN38, into diselenide bond-bridged organosilica nanoparticles, followed by coating with a Mn2+-based metal phenolic network. We show that this ISV can activate the STING pathway through Mn2+ and SN38 comediated signaling and simultaneously scavenge preexisting H2O2 in the TME and Mn2+-catalyzed •OH by leveraging the antioxidant property of diselenide and polyphenol. This ISV effectively activated DCs and protected them from oxidative damage, leading to remarkable downstream T cell activation and systemic antitumor immunity. This work highlights a nanoparticle design that manipulates DCs in the TME for improving the ISV.

Dual-layer probiotic encapsulation using metal phenolic network with gellan gum-tamarind gum coating for colitis treatment

Probiotic oral therapy has been recognised as an effective treatment for inflammatory bowel disease (IBD). However, the efficacy of probiotics is often diminished due to their limited resistance to harsh gastrointestinal conditions. Therefore, the importance of designing innovative strategies for oral probiotic delivery for the effective treatment of IBD is increasingly recognised. In this study, we present a novel encapsulation strategy of Lactobacillus plantarum (L.P) using the dual-layer system consisting of a tannic acid‑calcium network and polysaccharide coating (gellan gum-tamarind gum) named L.P-C/T-G/T. This double-layer encapsulation system not only does not affect the normal proliferation of probiotics and provide protection, but also endows probiotics with more functions. More specifically, the acid resistance ability of the encapsulated probiotics is increased by 10 times, the free radical scavenging rate is enhanced by 5 times, and the intestinal retention time can be prolonged by 6–12 h. In the DSS-induced murine colitis model, it significantly alleviated colon shortening, inhibited ROS overexpression, and promoted the repair and regeneration of the mucus layer. This dual-layer encapsulation approach for a single probiotic demonstrates a significant advancement in probiotic delivery technology, offering hope for a comprehensive approach to the treatment of colitis and potentially other gastrointestinal disorders.

A pH-responsive MOFs@MPN nanocarrier with enhancing antifungal activity for sustainable controlling myclobutanil release

The pH-responsive metal–organic framework (MOF) nanocarriers for sustainable controlled release of pesticides is promising in agricultural production owing to their long duration, high loading efficiency and antimicrobial activity. In this work, myclobutanil (MYC) was loaded into an Ag-based MOF (Ag-TCPP), and modified with a metal-phenolic network (MPN) via in-situ polymerization to construct a pH-responsive nano-delivery system (Ag-TCPP@MYC@MPN). Ag-TCPP@MYC@MPN presented a disordered nanoflower structure and many active sites with potential enhanced loading activity. The cumulative release rates of nanoparticles at pH 4.96, 7.5, and 8.5 were 52.6 %, 62.6 % and 80.0 %, respectively. Hence, Ag-TCPP@MYC@MPN has slow release rate and pH responsiveness. The antifungal activity of Ag-TCPP@MYC@MPN was significantly enhanced, and the bacteriostatic rate reached 81.8 %. This enhancement may be attributed to the synergistic antibacterial effect between tannic acid and Ag+. Safety experiments showed the nanoparticles had no inhibitory effect on the germination of Pakchoi seeds, and the pesticide residues of Ag-TCPP@MYC@MPN did not exceed the food safety standards. This work offers a new potential to develop improved responsive stimulus nanocarriers for sustainable controlled release of MYC.

Protein-driven interaction enhanced electrochemiluminescence biosensor of hydrogen-bonded biohybrid organic frameworks for sensitive immunoassay of disease markers

The oriented design of reticular materials as emitters can significantly enhance the sensitivity of electrochemiluminescence (ECL) sensing analysis for disease markers. However, due to the structural fragility of hydrogen bonds, relational research on hydrogen-bonded organic frameworks (HOFs) has not been thoroughly conducted. Additionally, the modulation of luminescence behavior through HOFs has been rarely reported. In view of this, hydrogen-bonded biohybrid organic frameworks (HBOFs) were synthesized and recruited for ECL immunoassay applications. HBOFs was easily prepared using 6,6′,6″,6‴-(pyrene-1,3,6,8-tetrayl)tetrakis(2-naphthoic acid) as linkers via bovine serum albumin (BSA) activated hydrogen-bonded cross-linking. The material exhibited good fluorescence emission characteristics. And the highly ordered topological structure and molecular motion limitation mediated by BSA overcome aggregation-caused quenching and generate strong aggregation induced emission, expressing hydrogen-bond interaction enhanced ECL (HIE-ECL) activity with the participation of tri-n-propylamine. Furthermore, a sandwich immunosensor was constructed employing cobalt-based metal-phenolic network (CMPN) coated ferrocene nanoparticles (FNPs) as quenchers (CMPN@FNPs). Signal closure can be achieved by annihilating the excited state through electron transfer from both CMPN and FNPs. Using a universal disease marker, carcinoembryonic antigen, as the analysis model, the signal-off sensor obtained a detection limit of 0.47 pg/mL within the detection range of 1 pg/mL - 50 ng/mL. The synthesis and application of highly stable HBOFs triggered by proteins provide a reference for the development of new reticular ECL signal labels, and electron transfer model provides flexible solutions for more sensitive sensing analysis.

Lightweight, compressible, elastic resorcinol-formaldehyde aerogels with cobalt-ligand-enhanced cross-linked skeletons

Resorcinol-formaldehyde (RF) aerogel materials exhibit remarkable properties such as low density, ablation resistance (high residual carbon rate), easily regulated pore structure and low thermal conductivity, making them promising for applications in adsorption, medicine and aerospace, among others. However, since their inception, RF aerogels have suffered from disadvantages such as brittleness and long preparation cycles, which have severely limited their widespread use. In order to improve the mechanical properties of RF aerogels, this paper presents a new synthetic route for obtaining strong elastic properties without introducing additional fiber reinforcement. Here, a lightweight, compressible, elastic resorcinol-formaldehyde aerogel with cobalt-ligand-enhanced cross-linked skeletons was prepared by sol-gel and freeze-drying methods using an alkali metal salt (cobalt (II) acetate) as a cross-linking agent and sodium acetate as a catalyst. The coordination of metal ions (Co2+) with resorcinol resulted in the formation of a structure analogous to a metal-phenolic network (MPN), which altered the crosslinking mode and degree of crosslinking of the RF aerogel. This process led to the thickening of the skeletal structure of the sample. Concurrently, a multilayered pore structure was generated within the interior under the appropriate pH conditions, which contributed to the strengthening of the skeleton of the samples and a reduction in thermal conductivity. The obtained RF-Co aerogel can withstand 68.6 % compression change without fracture and shows good elastic deformation at 35 % compression rate, while the aerogel exhibits low thermal conductivity (0.039 W (m K)−1) and low density (0.09 g cm−3).

Crystalline Metal–Organic Framework Coatings Engineered via Metal–Phenolic Network Interfaces

AbstractCrystalline metal–organic frameworks (MOFs) have garnered extensive attention owing to their highly ordered porous structure and physicochemical properties. However, their practical application often requires their integration with various substrates, which is challenging because of their weakly adhesive nature and the diversity of substrates that exhibit different properties. Herein, we report the use of amorphous metal–phenolic network coatings to facilitate the growth of crystalline MOF coatings on various particle and planar substrates. Crystalline MOFs with different metal ions and morphologies were successfully deposited on substrates (13 types) of varying sizes, shapes, and surface chemistries. Furthermore, the physicochemical properties of the coated crystalline MOFs (e.g., composition, thickness) could be tuned using different synthesis conditions. The engineered MOF‐coated membranes demonstrated excellent liquid and gas separation performance, exhibiting a high H2 permeance of 63200 GPU and a H2/CH4 selectivity of 10.19, likely attributable to the thin nature of the coating (~180 nm). Considering the vast array of MOFs available (>90,000) and the diversity of substrates, this work is expected to pave the way for creating a wide range of MOF composites and coatings with potential applications in diverse fields.

Crystalline Metal-Organic Framework Coatings Engineered via Metal-Phenolic Network Interfaces.

Crystalline metal-organic frameworks (MOFs) have garnered extensive attention owing to their highly ordered porous structure and physicochemical properties. However, their practical application often requires their integration with various substrates, which is challenging because of their weakly adhesive nature and the diversity of substrates that exhibit different properties. Herein, we report the use of amorphous metal-phenolic network coatings to facilitate the growth of crystalline MOF coatings on various particle and planar substrates. Crystalline MOFs with different metal ions and morphologies were successfully deposited on substrates (13 types) of varying sizes, shapes, and surface chemistries. Furthermore, the physicochemical properties of the coated crystalline MOFs (e.g., composition, thickness) could be tuned using different synthesis conditions. The engineered MOF-coated membranes demonstrated excellent liquid and gas separation performance, exhibiting a high H2 permeance of 63200 GPU and a H2/CH4 selectivity of 10.19, likely attributable to the thin nature of the coating (~180 nm). Considering the vast array of MOFs available (>90,000) and the diversity of substrates, this work is expected to pave the way for creating a wide range of MOF composites and coatings with potential applications in diverse fields.

Self-assembly metal phenolic network coating improves the controlled release and bacteriostatic properties of Litsea cubeba essential oil-loaded ε-polylysine-pectin nanoparticles

Pectin and ε-polylysine (ε-PL) nanoparticles loaded with Litsea cubeba essential oil (LEO) (PP-LNPs) were prepared through the electrostatic interaction. Metal phenol network (MPN) coatings, designated as MPN@PP-LNPs, were fabricated on the surface of the nanoparticles via self-assembly process of tannic acid (TA) and FeIII to develop food preservative materials with pH-responsive controlled release. The morphology, encapsulation efficiency, and pH-responsive release characteristics of MPN@PP-LNPs were investigated. The results showed that the particle size of MPN@PP-LNPs was 432.5 ± 58.6 nm. Furthermore, the encapsulation efficiencies of ε-PL and LEO were 83.26 ± 2.21% and 30.78 ± 3.92%, respectively. TA was rapidly released at low pH, while LEO exhibited controlled release over a wide pH range (pH 1.2–9.0). In addition, the MPN coating has been demonstrated to enhance antioxidant activity and inhibit the growth of E. coli and S. aureus under acidic conditions. Furthermore, preliminary evidence suggests that MPN@PP-LNPs are not cytotoxic. In conclusion, MPN@PP-LNPs, prepared through the self-assembled surface modification of TA and FeIII, was an effective material for food preservation.

Multifunctional Microneedle Patch Based on Metal-Phenolic Network with Photothermal Antimicrobial, ROS Scavenging, Immunomodulatory, and Angiogenesis for Programmed Treatment of Diabetic Wound Healing.

In diabetic patients with skin injuries, bacterial proliferation, accumulation of reactive oxygen species (ROS) in the tissues, and impaired angiogenesis make wound healing difficult. Therefore, eliminating bacteria, removing ROS, and promoting angiogenesis are necessary for treating acute diabetic wounds. In this study, benefiting from the ability of polyphenols to form a metal-phenolic network (MPN) with metal ions, TA-Eu MPN nanoparticles (TM NPs) were synthesized. The prepared photothermal agent CuS NPs and TM NPs were then loaded onto the supporting base and needle tips of PVA/HA (PH) microneedles, respectively, to obtain PH/CuS/TM microneedles. Antibacterial experiments showed that microneedles loaded with CuS NPs could remove bacteria by the photothermal effect. In vitro experiments showed that the microneedles could effectively scavenge ROS, inhibit macrophage polarization to the M1 type, and induce polarization to the M2 type as well as have the ability to promote vascular endothelial cell migration and angiogenesis. Furthermore, in vivo experiments showed that PH/CuS/TM microneedles accelerated wound healing by inhibiting pro-inflammatory cytokines and promoting angiogenesis in a diabetic rat wound model. Therefore, PH/CuS/TM microneedles have efficient antibacterial, ROS scavenging, anti-inflammatory, immunomodulatory, and angiogenic abilities and hold promise as wound dressings for treating acute diabetic wounds.

A Metal-Phenolic Network-Enabled Nanoadjuvant to Modulate Immune Responses.

The presence of hierarchical suppressive pathways in the immune system combined with poor delivery efficiencies of adjuvants and antigens to antigen-presenting cells are major challenges in developing advanced vaccines. The present study reports a nanoadjuvant constructed using aluminosilicate nanoparticles (as particle templates), incorporating cytosine-phosphate-guanosine (CpG) oligonucleotides and small-interfering RNA (siRNA) to counteract immune suppression in antigen-presenting cells. Furthermore, the application of a metal-phenolic network (MPN) coating, which can endow the nanoparticles with protective and bioadhesive properties, is assessed with regard to the stability and immune function of the resulting nanoadjuvant in vitro and in vivo. Combining the adjuvanticity of aluminum and CpG with RNA interference and MPN coating results in a nanoadjuvant that exhibits greater accumulation in lymph nodes and elicits improved maturation of dendritic cells in comparison to a formulation without siRNA or MPN, and with no observable organ toxicity. The incorporation of a model antigen, ovalbumin, within the MPN coating demonstrates the capacity of MPNs to load functional biomolecules as well as the ability of the nanoadjuvant to trigger enhanced antigen-specific responses. The present template-assisted fabrication strategy for engineering nanoadjuvants holds promise in the design of delivery systems for disease prevention, as well as therapeutics.

Cobalt-phenolic nanoparticles-driven self-assembly of hyaluronic acid hydrogels providing a multifactorial approach for chronic wound management

Chronic wounds are persistent non-healing lesions whose complex management is due to the interplay of multiple factors promoting chronicity, such as oxidative stress, overexpressed enzyme activities impeding the tissue repair and bacterial contamination. Currently marketed chronic wound dressings are designed mainly to absorb wound exudate, and at most to release antimicrobial agents, usually ionic silver. However, an effective wound repair requires addressing the multifactorial nature of the wound in a holistic approach. This study explores the potential of metal phenolic network (MPN) nanoparticles (NPs), comprised of epigallocatechin gallate (EGCG) and cobalt, as active agents and structural elements in wound dressings. The MPN NPs were able to generate reactive oxygen species (ROS), disturb bacterial membrane, and inhibit the biofilm of both gram-positive Staphylococcus aureus and gram-negative Pseudomonas aeruginosa. Owing to the high interfacial activity of their phenolic shells, the NPs drove the self-assembly of thiolated hyaluronic acid (THA) hydrogels featuring injectability, self-healing, stimuli-responsive NPs delivery in wound microenvironment, and control over deleterious enzyme activities, oxidative stress and bacterial colonisation. Specifically, the hydrogels inhibited matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) by 60 and 80 %, respectively, and achieved 4-log reduction of S. aureus and 2-log reduction of P. aeruginosa concentrations. Finally, the hydrogels were in-vivo validated in a mouse animal model, showing lack of toxicity and similar wound healing efficiency as an antibiotic-containing commercial product.

Effect of Fe(III) on soybean protein-gallic acid hydrogel: Structure, functional properties, and digestive properties

A soy protein isolate-gallic acid (SPI-GA) complex was synthesized, mediated using 1-ethyl-3-(3-dimethylaminopropyl) carbodiimide hydrochloride and N-hydroxysuccinimide. Different amounts of Fe3+ were then added to the SPI-GA complex to produce hydrogels (SPA@Fe) containing metal-phenolic network without heating the protein. Spectral analysis revealed that these hydrogels contained multiple modes of cross-linking, such as Schiff bases, hydrogen bonds, and coordination bonds. Coordination bonds formed between GA and Fe3+ mainly had a coordination number of three, and they changed the structure of the protein. Furthermore, these coordination bonds also endowed SPA@Fe with a more compact crosslinked network, thus improving the hydrogel's textural characteristics, thermal stability, storage modulus, and glucose adsorption capacity. The SPA@Fe hydrogel exhibited the best performance when the molar ratio of GA to Fe3+ was 1, with the thermal stability, hardness, springiness, and glucose adsorption capacity being 3.9, 1.84, 1.22, and 1.93 times higher than those of the SPI-GA hydrogel, respectively. Moreover, in-vitro digestion tests showed that SPA@Fe could control the release of loaded curcumin, had good capacity for adsorbing bile salt, and showed delayed degradation. This hydrogel system may offer a safe and feasible way to deliver bioactive substances such as curcumin.

A POSS-Based Metal-Phenolic Network with Coupled Hardness and Softness for Photodynamic-Immunotherapy of Triple-Negative Breast Cancer

A POSS-Based Metal-Phenolic Network with Coupled Hardness and Softness for Photodynamic-Immunotherapy of Triple-Negative Breast Cancer

Metal-Phenolic Network-Coated Nanoparticles as Stabilizers for the Engineering of Pickering Emulsions with Bioactivity.

Pickering emulsions stabilized by functional nanoparticles (NPs) have received considerable attention for improving the physical stability and biological function of NPs. Herein, hydrophobic polyphenols were chosen as phenolic ligands to form metal-phenolic network (MPN) coatings on NPs (e.g., silica, polystyrene) mediated by the sono-Fenton reaction. The MPN coatings modulated the surface wettability and charges of NPs and achieved emulsification behavior for preparing Pickering emulsions with pH responsiveness and oxidation resistance. A series of polyphenols, including resveratrol, rutin, naringin, and curcumin, were used to form MPN coatings on NPs, which served as stabilizers for the engineering of functionalized oil-in-water (O/W) Pickering emulsions. This work provides a new avenue for the use of hydrophobic polyphenols to modulate NP emulsifiers, which broadens the application of polyphenols for constructing Pickering emulsions with antioxidant properties.

Surface modification of nitrocellulose by interfacial self-assembly of metal-phenolic network for enhanced thermal stability and eco-friendly propulsion energy

Metal-phenolic networks (MPNs) have received widespread interest owing to their ability to incorporate metal ions and phenolic ligands in a modular manner. However, the effect of MPNs on nitrocellulose (NC), an energetic material for propulsion, has not been extensively investigated. Herein, we fabricated MPN-coated NC fibers (NC@MPN) and confirmed the successful coating and homogeneous distribution of MPN on the surface of NC through Raman spectroscopy, X-ray photoelectron spectroscopy (XPS), UV–visible spectroscopy, scanning electron microscopy (SEM) and Energy Dispersive spectroscopy (EDS). The thermal stability of NC was enhanced as evidenced by differential scanning calorimetry (DSC), accelerating rate calorimetry (ARC) and the ignition point test. The thermal decomposition activation energy of NC@MPN can reach 200.73 kJ•mol−1, 7.50 % higher than that of NC primitive fiber (186.72 kJ•mol−1). The ARC tests demonstrate that the implementation of MPN coating prolonged the time of entering the adiabatic section by 5.4 °C and the forecast temperatures for TD8 and TD24 have increased by 4.6 and 4.8 °C, respectively. Additionally, the ignition point was also raised by 2 °C. The aforementioned three experimental results provide evidence for the enhanced thermal stability conferred by MPNs. Besides, thermogravimetric analysis (TGA) results demonstrate a reduction in the residue from thermal decomposition. The present study presents a simple and robust coating strategy for the modular surface engineering of energetic materials, which significantly improves thermal stability and reduces the residues of thermal decomposition.

Copper-phenolic coating constructed on silicone urinary catheters to prevent catheter-associated infections

Catheter-associated infections (CAIs) are serious issues in clinics, significantly affecting patient morbidity, mortality, and incurring substantial treatment costs. Hence, the development of a novel strategy to endow surfaces with antibacterial function is particularly important for catheter materials. In this work, Tannic acid (TA) and various concentrations of copper (Cu) were used to construct metal-phenolic network (MPN) coatings to impart silicone catheters antibacterial surfaces (TA/Cu5, TA/Cu5 and TA/Cu25). The prepared copper-phenolic coatings exhibited desirable biocompatibility towards mammalian cells and remarkable antibacterial properties against Staphylococcus aureus (S. aureus), Escherichia coli (E. coli) and even “superbug” such as methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus (VRE). The antibacterial properties of the MPN coatings were attributed to the combined effects of Cu and TA. Among all MPN coated silicone catheters, TA/Cu25 (10 mM TA and 250 mM CuCl2·2 H2O) exhibited the highest antibacterial activity with killing ratios of 99.84%, 98.67%, 99.85%, and 99.90% against S. aureus, E. Coli, MRSA and VRE, respectively. Thus, the MPN has significant potential for developing antibacterial surface coatings for silicone catheters, which can effectively mitigate CAIs.

Innovative wearable solutions: Semi-releasing ion-conductive lignin hydrogel sensors for enhanced practicability

The severe negative effects of impurities adhering to the external surface of wearable devices can significantly influence the signal transmission, performance, and lifespan of hydrogel sensors. Herein, we developed an ion-conducting hydrogel sensor with a strong adhesive side and a non-adhesive side, similar to a “semi-releasing material.” This hydrogel, formulated using deep eutectic solvents obtained from choline chloride and acrylic acid, contained lignin. This versatile material, exhibiting properties similar to semi-releasing materials, was treated with an AlCl3 solution on one side. Additionally, the hydrogel was successfully used as a highly adhesive strain sensor for real-time monitoring of various human activity signals. Moreover, the hydrogel demonstrated excellent environmental tolerance and conductivity. Lignin extracted from wood flour endowed the hydrogel sensor with excellent adhesion energy (up to 427.1 J/m2) and UV resistance. Treatment of hydrogels with AlCl3 completely eliminated their adhesiveness, thereby enhancing fracture elongation and tensile strength. This improvement can be attributed to the absence of carboxyl groups and the formation of a metal-phenolic network. The implementation of this convenient and efficient strategy provides a more feasible approach to address challenges related to impurity adhesion and signal transmission in flexible wearable devices.