Search Results (1,115)

Despite the demand for personalized wound care, integrating diagnostics and therapeutics into a unified platform remains a significant challenge. To address this, we developed a 3D-printed theranostic hydrogel using vat photopolymerization, enabling precise, multifunctional wound management. The hydrogel matrix, composed of poly(acrylamide-co-hydroxyethyl acrylate) and carboxymethyl cellulose, was chemically crosslinked with poly(ethylene glycol) diacrylate. Bromocresol purple was integrated into the photosensitive resin to enhance printing fidelity and serve as a diagnostic indicator, providing a distinct colorimetric shift upon skin infection. For controlled drug delivery, graphene oxide (GO) and levofloxacin were incorporated into the system. The 3D-printed hydrogel demonstrated superior swelling capacity (>600%), ideal for absorbing wound exudate. A semi-quantitative linear colorimetric response was observed across varying pH levels, allowing for clear differentiation between healthy healing skin (pH 4.0–6.0) and infected conditions (pH 7.0 and above). Furthermore, the hydrogel exhibited infection-stimulated therapy, with a cumulative levofloxacin release of 92.63% at pH 8, significantly higher than in acidic conditions. Moreover, the incorporation of GO further optimized the delivery profile by tuning absorption and release rates. Synergizing real-time monitoring and on-demand therapeutic action, this 3D-printed system offers a scalable, robust solution for future-ready, personalized wound management. Full article

Two hemostatic bionanocomposite dressings were developed using natural, semi-natural (or semi-synthetic) and synthetic polymers. The first system consisted of chitosan (CS), polyvinyl alcohol (PVA), and carboxymethyl cellulose (CMC) (CS/PVA/CMC), while the second was based on CS, PVA, and starch (SR) (CS/PVA/SR). Zinc oxide (ZnO) nanoparticles and bicyclic monoterpene camphor (CP) ketone were incorporated as bioactive agents in order to enhance antimicrobial and hemostatic performance. FTIR spectroscopy confirmed the successful solvent casting synthesis of the dressings and the interactions between the biopolymers and additives. XRD analysis indicated a predominantly amorphous structure, while SEM images and EDS analysis revealed uniform dispersion of ZnO particles within the polymer matrices without aggregation. Furthermore, the CS/PVA/CMC-1ZnO/CP sample exhibited a water sorption of 12,666 ± 126%, while CS/PVA/SR-1ZnO/CP reached 7013 ± 215%. ZnO incorporation also improved mechanical performance, with CS/PVA/SR-2ZnO/CP displaying the highest tensile strength (39.18 ± 0.2 MPa) and elongation at break (9.54 ± 1.04%). ZnO incorporation also led to a concentration-dependent increase in antibacterial activity, with SR-based dressings achieving near-complete bacterial reduction at higher ZnO loadings. All the dressings demonstrated good biocompatibility, while CS/PVA/SR-1ZnOCP showed the fastest clotting time (420s ± 40), highlighting its potential for hemostatic applications. Full article

N-methylmorpholine N-oxide (NMMO monohydrate) is widely used for cellulose fibre production, as in the Lyocell process. However, fibre spinning from denim wastes remains significantly more complex due to its higher viscosity, the presence of indigo dye, and NMMO’s temperature sensitivity. These factors together create serious challenges for denim dissolution and fibre regeneration. This study presents a comprehensive rheological and structural characterisation of regenerated cellulose fibres derived from waste denim dissolved in NMMO. Oscillatory and steady-state rheological tests were conducted across concentrations (4–8 wt%) and temperatures (60–90 °C) to determine optimal spinning conditions. A 6% denim/NMMO solution at 80 °C displayed the most favourable rheological balance within the investigated concentration window (4–8 wt%), moderate complex viscosity, well-defined viscoelastic transitions, and a Tan δ value (~0.94) consistent with stable jet formation in air-gap spinning. Steady shear tests confirmed strong shear-thinning behaviour and mechanical predictability, essential for spinneret extrusion. Thermal ramp experiments validated 80 °C as the upper safe limit, balancing flow processability with structural integrity while avoiding solidification or NMMO degradation. The identified rheological parameters fall within ranges reported for spinnable cellulose dopes in air-gap spinning systems, suggesting strong potential for fibre formation under controlled conditions. These findings establish a robust rheological framework for denim-derived cellulose in NMMO and provide a foundation for future investigations into controlled fibre spinning and process scale-up in sustainable textile recycling. Full article

Wood coatings play a critical role in protecting wood substrates from environmental degradation, particularly ultraviolet (UV)-induced photodegradation. This review comprehensively examines the mechanisms of wood coating photodegradation, the factors influencing their durability, and current anti-aging strategies. Photodegradation arises from polymer chain scission, chemical structure reorganization, and photo-oxidation of lignin and cellulose, leading to coating chalking, cracking, gloss loss, and color changes, ultimately compromising wood mechanical properties and service life. Key anti-aging strategies include UV absorbers, which convert harmful UV radiation into heat; hindered amine light stabilizers (HALSs) that capture free radicals and quench excited-state molecules; barrier and shielding materials that form dense physical or nanostructured networks to block UV penetration and enhance mechanical and water resistance; and antioxidants that neutralize free radicals or decompose peroxides at the molecular level. Each approach can be employed individually or synergistically to enhance coating durability. Challenges remain in achieving long-term outdoor stability, balancing transparency and UV shielding, optimizing nanoparticle dispersion, and maintaining the activity of natural antioxidants. Future research should focus on multifunctional composite coatings integrating bio-based materials and nanotechnology, smart responsive systems, adaptive protection mechanisms, and standardized long-term evaluation protocols. These advancements will facilitate the development of high-performance, sustainable wood coatings and promote the value-added utilization of wood resources. Full article

Bagasse, owing to its low cost and high carbon yield, is a promising precursor for hard-carbon anodes in sodium-ion batteries (SIB). Regulating the microcrystalline state and pore architecture during pyrolysis is key to boosting Na⁺ storage behavior. Here, the pyrolysis kinetics is controlled via stepwise carbonization to construct a defect-ordered island structure within the cellulose-derived carbon skeleton. Retaining sp³-hybridized carbon at low temperatures creates the Na⁺ channel, while acid cleaning selectively dissolves residual metal oxides, removing the electrochemical inert phase and promoting improved ion diffusion. This process also enriches active sites and interlayer spacing in the hard carbon, boosting capacity in the plateau region. In addition, the ash-catalyzed formation of local sp² graphite microcrystals provides electron transport nodes, optimizing Na⁺ diffusion and electronic conductivity. Accordingly, the assembled SIB achieves a high reversible capacity of 378 mAh g⁻¹ at 0.1C and an initial coulombic efficiency of 97%, with the plateau capacity accounting for 59.1% of the total reversible capacity. This work presents a universal thermochemical approach for engineering high-performance carbon anodes with high closed porosity from low-cost biomass precursors, advancing the development of sustainable and efficient SIBs. Full article

The present work aimed to obtain antibacterial wound dressings using bacterial cellulose (BC) as a support, to improve wound treatment and reduce the incidence of infections. To enhance the antibacterial activity of the synthesized dressings, the introduction of ZnO nanoparticles into the BC network by precipitation was pursued. The method chosen to develop ZnO NPs was green synthesis, an ecological and sustainable method for obtaining nanomaterials using plant extracts as reducing agents or stabilizers. Thus, the chosen plants were Ginger rhizomes, Bay leaves, and Rose hips, in both fresh and dry form, due to the natural benefits they possess, and the Soxhlet method was used to obtain the plant extracts desired to be used in the synthesis. The composite dressings were developed in two distinct sample series, differentiated by the immersion time of BC in the precursor Zn²⁺ solution. The samples in the first series were obtained by precipitation in a mixture of Zn²⁺ solution and natural extract, whereas the samples in the second series were obtained by successive immersion in Zn²⁺ solution and then in natural extract, which demonstrated a considerable difference. The best antimicrobial activity tested against Gram-negative bacterium Escherichia coli was recorded for the composite material obtained in the presence of fresh rose hip extract, an aspect most likely related to the morphological and crystalline features of the ZnO phase, but also to the phytochemical profile of the extract used. Such eco-friendly materials represent valuable candidates for wound dressing applications due to their ability to support wound healing, relief burns, and skin irritation, provide antimicrobial protection, promote skin regeneration and reduce scarring, protect sensitive skin, and act as a barrier against external contaminants. Full article

As a novel organic semiconductor derived from biomass, hydrothermal carbonation carbon (HTCC) usually exhibits an amorphous structure due to its well-recognized formation pathway based on 5-hydroxymethylfurfural (HMF), which impedes charge transfer and consequently restricts the photocatalytic activity. Herein, we report a crystalline HTCC photocatalyst produced via an unusual synthesis route applied to cellulose in the presence of an oxidant. Notably, the crystalline structure of cellulose was retained and became highly aromatized during the process, leading to significantly enhanced charge transfer efficiency and an increased density of active sites. Moreover, unlike other reported HTCC photocatalysis, the highly active hydrogen radicals (H•) were identified as the dominant active species governing photocatalytic Cr(VI) reduction over crystalline HTCC. As a result, this crystalline HTCC exhibited dramatically enhanced photocatalytic removal efficiencies of Cr(VI) and microcystin-LR (MC-LR) due to the highly efficient charge transfer, abundant active sites as well as highly active hydrogen radicals. Full article

Pyranose oxidases (POXs, EC 1.1.3.10) are a class of fungal FAD-dependent oxidoreductases with potential for lignocellulosic bioconversion because they generate H₂O₂ during sugar oxidation. Despite their known catalytic properties, the role of these enzymes in promoting lignocellulose enzymatic saccharification remains largely unexplored. In this study, POXs from Phanerochaete chrysosporium (PcPOX) and Trametes versicolor (TvPOX) were comparatively evaluated through biochemical characterization, kinetic analysis, molecular simulation, and supplementation for lignocellulose hydrolysis. PcPOX exhibited a broader substrate spectrum and a slightly higher optimum temperature, whereas TvPOX demonstrated greater stability under acidic and hydrolysis-relevant conditions and a longer half-life at 50 °C. TvPOX also showed a numerically lower apparent K_m toward D-glucose, while the apparent catalytic efficiencies were comparable between the two enzymes. Molecular simulation results suggested more stable glucose binding in TvPOX. Accordingly, TvPOX was selected for hydrolysis experiments and was shown to increase the measured glucan conversion of phosphoric acid-swollen cellulose, Avicel, and corncob residue. Mixture design analysis further indicated that this positive effect depended on balanced peroxide regulation, with low catalase supplementation providing better performance. These results identify TvPOX as a promising auxiliary enzyme for cellulase-based lignocellulosic saccharification. Full article

The rapid advancement of communication technologies exacerbates severe electromagnetic interference (EMI) pollution. Conventional flexible shielding materials rely heavily on non-degradable petroleum-based polymers, aggravating the electronic waste crisis. To address this dual challenge, sustainable biomass-derived TEMPO-oxidized cellulose nanofibrils (TOCNFs) emerge as ideal structural substrates. However, their intrinsic electrical insulation necessitates integrating conductive two-dimensional (2D) MXene, which suffers from severe self-restacking and brittleness. Herein, TOCNFs@MXene hybrid films are manufactured via vacuum filtration and hot-pressing densification. TOCNFs inhibit MXene self-restacking, constructing a highly ordered layered architecture via a dense hydrogen-bonded network. The optimized ultrathin film T5@M20 (~4.92 μm) exhibits an electrical conductivity of 1.09 × 10⁶ ± 5.06 × 10⁴ s m⁻¹ and an X-band shielding effectiveness (SE_Total) of 25.55 dB. Demonstrating an ultrahigh thickness-normalized specific shielding effectiveness (SSE/t) of 51,934.72 dB·cm²·g⁻¹, this sustainable architecture shows exceptional potential for next-generation flexible electronics. Full article

Low-molecular-weight gelators (LMWGs) have attracted growing attention as versatile alternatives to conventional polymeric thickeners and gelators, owing to their ability to form three-dimensional fibrillar networks through non-covalent self-assembly and to undergo reversible sol–gel transitions in response to external stimuli. Among the various stimuli that can be exploited, pH represents a particularly attractive trigger given its direct relevance to biological and physiological environments. This review focuses on three categories of pH-responsive LMWGs that have shown notable progress over the past decade yet remain relatively underexplored in the literature. First, N-oxide-type hydrogelators are discussed, with emphasis on amide amine oxide-based surfactants and pyridine-N-oxide frameworks. The pH-dependent protonation of the N-oxide moiety modulates intermolecular hydrogen bonding, thereby governing self-assembly and gel formation. The structural versatility of these gelators enables rational tuning of aggregate morphology and confers clear pH and temperature responsiveness. Second, recent advances in phenylboronic acid-based LMWGs are highlighted. Although boronic acid derivatives have long been studied as dynamic crosslinking units in polymeric hydrogels, 3-isobutoxyphenylboronic acid was recently identified as the first example of phenylboronic acid functioning as an LMWG, in which gelation is driven primarily by hydrogen bonding and pH responsiveness is exploited for stimuli-triggered gel disruption rather than gel formation. Third, pH-responsive orthogonal self-assembly systems are reviewed. Representative examples include multicomponent hybrid hydrogels combining pH-activated LMWGs with polymer gelators for controlled drug release, pH-triggered self-sorting of two LMWGs without any polymeric component, and bio-based orthogonal hydrogels composed of a glucolipid LMWG and cellulose nanocrystals. For each system, both advantages and remaining limitations are critically assessed. Collectively, this review aims to provide a timely overview of emerging trends in pH-responsive LMWG research and to offer perspectives on the rational design of next-generation stimuli-responsive soft materials. Full article

In this study, a cellulose nanocrystal (CNC)-supported Ag–ZnO nanocomposite was synthesized via a hydrothermal route as a polymeric photocatalyst for efficient UV-A light-driven dye degradation. The renewable CNC framework provides abundant hydroxyl functional groups for nanoparticle anchoring, enhancing dispersion and interfacial charge transfer. Structural (XRD, FTIR, TEM, PL, and XPS) and thermal (TGA and DTG) analyses confirm successful incorporation of Ag nanoparticles and retention of CNC crystallinity. The composite exhibits a reduced optical bandgap (3.02 eV) and demonstrates superior photocatalytic activity, achieving 96% methylene blue (MB) degradation within 120 min. Enhanced performance is attributed to the synergistic effect of Ag-induced plasmonic excitation and CNC-facilitated charge migration, effectively suppressing ZnO photocorrosion. Moreover, the optimization of the parameters was conducted and found to be pH 7, a catalyst dose of 0.3 g L⁻¹, and an initial MB concentration of 10 ppm, which shows the best photocatalytic degradation reaction. The CNC/Ag–ZnO catalyst maintains 87% activity after five reuse cycles, showing good stability and reusability. The photostability of the CNC/Ag–ZnO catalyst was evaluated by ICP-MS, which measured Zn²⁺ concentration in the aqueous solution. Additionally, the degraded MB compounds were identified using GC-MS/MS analysis. This work highlights the potential of polymer-based biogenic supports for sustainable photocatalyst design and bridges polymer science with environmental remediation technology. Full article

Background and Objectives: Postoperative pain and intra-abdominal adhesions are common complications following surgery. Pain delays early mobilization, whereas adhesions can lead to bowel obstruction, chronic pain, or infertility. Current treatments, including systemic analgesics and physical barrier methods, are only partially effective. We hypothesized that combining these modalities would yield superior outcomes. Accordingly, we investigated whether a lidocaine-loaded alginate–carboxymethyl cellulose–polyethylene oxide (ACPE) electrospun film could more effectively reduce both postoperative pain and adhesion formation than either component alone. Materials and Methods: An electrospun nanofiber film composed of ACPE containing lidocaine was prepared. Its effects were evaluated in rats using an incisional pain and a peritoneal adhesion model. Four groups were compared: saline control, free lidocaine, drug-free ACPE film, and lidocaine-loaded ACPE film. Fifteen rats were allocated to each group. The primary outcome was the mechanical withdrawal threshold (MWT) after plantar incision, while secondary outcomes included histological changes and adhesion scores assessed by the Moreno system. Results: The lidocaine–ACPE film significantly increased MWT compared with all other groups, demonstrating a stronger and longer-lasting analgesic effect than free lidocaine. Adhesion scores were also lowest in the film group. Histological analysis confirmed a reduction in inflammatory cell infiltration and collagen deposition. Conclusions: A lidocaine-loaded ACPE nanofiber film effectively reduced both postoperative pain and adhesion formation in a rodent model. The combination of sustained local drug release and physical barrier function provides a promising strategy to address two major postoperative complications. Further preclinical studies are warranted before clinical application. Full article

This study presents a highly efficient and sustainable biocatalytic platform for bisphenol A (BPA) bioremediation through the covalent immobilization of laccase onto hierarchically functionalized cotton fibers. The immobilization strategy involved selective periodate oxidation of cellulose, grafting a hexamethylenediamine (HMDA) spacer arm, and glutaraldehyde activation, ensuring stable covalent attachment. Characterization via FTIR, SEM, and BET confirmed successful surface modification and high enzyme loading, achieving an immobilization yield of 90.5%. The immobilized laccase (CT-DA-HMD-Lac) exhibited significantly enhanced performance compared to the free enzyme, with a two-fold increase in maximum reaction velocity (V_max) and a 75% improvement in catalytic efficiency of action (V_max/K_m). Furthermore, the biocatalyst demonstrated superior robustness, maintaining high activity across broader pH and temperature ranges, and retaining 75% of its initial activity after 15 consecutive reusability cycles. Storage stability was also markedly improved, with 83% activity retention after 60 days. Practical application in BPA degradation showed 85% removal efficiency within 300 min, a 2.4-fold increase in the degradation rate constant over the free enzyme. These results highlight functionalized cotton as a promising, cost-effective, and scalable support for advanced enzymatic wastewater treatment and the remediation of persistent endocrine-disrupting chemicals. Full article

In this work, sodium alginate (NaAlg) membranes were enhanced with synthesized zinc oxide (ZnO) nanoplates to enable efficient pervaporation dehydration of isopropyl alcohol (IPA). A comprehensive suite of characterisation techniques—scanning electron (SEM) and atomic force (AFM) microscopy, Fourier-transform infrared (FTIR) spectroscopy, nuclear magnetic resonance (NMR), X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), thermogravimetric analysis (TGA), contact angle and liquid uptake measurements—along with density functional theory (DFT) calculations, was employed to establish robust structure–property relationships and to elucidate filler–polymer interactions. Membranes with different ZnO contents were prepared, and membranes based on the optimal NaAlg-ZnO(5%) composite were cross-linked with CaCl₂ to improve stability in aqueous solutions, and supported membranes were developed for prospective applications by applying this composite onto the prepared porous cellulose acetate (CA) substrate. This developed cross-linked supported NaAlg-ZnO(5%)/CA membrane had a permeation flux increased by 2 times or more compared to a dense NaAlg membrane during dehydration of IPA (12–30 wt.% water) with a permeate water content above 99 wt.%. The integrated experimental–theoretical approach provides mechanistic insight into ZnO–NaAlg interactions and demonstrates the strong potential of these mixed matrix membranes for high-efficiency alcohol dehydration, offering a rational design paradigm for next-generation pervaporation membranes. Full article

The enzymatic saccharification of cellulose remains a key step in biomass conversion processes, often influenced by enzyme stability, distribution, and accessibility at solid–liquid interfaces. Immobilization of cellulolytic enzymes on nanostructured supports has been proposed as a strategy to modulate catalytic behavior; however, the relationship between enzyme loading and catalytic response remains insufficiently understood. In this study, CuO-based nanobiocatalysts were prepared through controlled cellulase immobilization and systematically evaluated under defined experimental conditions. Structural and physicochemical characterization was performed using X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), scanning electron microscopy (SEM), and integrated thermal analysis (TGA–DTG–DSC), enabling a comparative assessment of the analyzed systems. SEM analysis showed that the average particle diameter increased from 39.5 ± 14.8 nm (CuO nanoparticles) to 95.6 ± 21.8 nm (NPI10), 106.6 ± 27.7 nm (NPI15), and 113.5 ± 23.1 nm (NPI20), indicating progressive variations in particle organization with increasing enzyme loading. Catalytic performance was evaluated through enzymatic hydrolysis of cellulose filter paper as a model substrate, with products quantified by HPLC at a representative reaction time. The system prepared at lower enzyme loading (NPI10) exhibited product formation comparable to that of the free enzyme, with apparent average glucose formation values of 1.054 and 1.047 mg·mL⁻¹·h⁻¹, respectively. In contrast, higher immobilization levels were associated with reduced catalytic output. Across all systems, glucose was the predominant product, with negligible accumulation of intermediate oligomers under the evaluated conditions. These results indicate that increasing enzyme loading does not correspond to proportional increases in product formation and highlight the influence of enzyme distribution and accessibility within the system. The combined structural and catalytic observations provide a controlled framework for evaluating how immobilization conditions influence system behavior in nanobiocatalytic systems. Full article