Search Results (3,948)

Hemostatic biomaterial agents are widely used during surgery and trauma care to control bleeding, yet their effects on wound healing remain incompletely understood. This study evaluated the impact of oxidized non-regenerated cellulose (ONRC), oxidized regenerated cellulose (ORC), and a gelatin-based hemostat (GELA) on wound healing at 14 and 30 days in a mouse model. Full-thickness wounds were created in C57BL/6J mice (n = 192) and compared to sham controls. Tissue samples were analyzed histologically, supported by immunohistochemistry for Ki-67 and α-SMA and qPCR for VEGF, TGF-β, and FGF-2. Histology demonstrated preserved tissue architecture across groups with progressive resorption of cellulose-based materials, whereas GELA showed localized fibrous structures and enhanced extracellular matrix formation. At day 14, no significant differences were observed in proliferation, contraction, VEGF, or FGF-2 expression; however, TGF-β was significantly reduced in the ORC group. By day 30, GELA significantly increased epidermal proliferation, while contraction markers were elevated in both GELA and ORC. VEGF expression was reduced in GELA and ORC, whereas ONRC showed increased TGF-β expression. FGF-2 remained unchanged across groups. All investigated hemostatic materials were well tolerated during the early postoperative phase (up to day 14), indicating short-term biocompatibility within the scope of this model. In contrast, material-specific differences in cellular activity and growth factor expression became apparent during the later remodeling phase (day 30). These findings suggest differential effects on cellular and molecular aspects of tissue remodeling; however, no conclusions can be drawn regarding overall healing quality or clinical safety, as no quantitative macroscopic or functional outcome measures were assessed. Full article

A warm-up is a critical procedure in sports science for enhancing muscular performance and optimizing subsequent athletic activities. However, the physiological and athletic performance effects of a warm-up are often transient, diminishing rapidly during the period of inactivity after the warm-up, which is known as the warm-up transition phase. In this study, a multi-functional thermoregulation wearable composite film of graphene–MXene–bacterial cellulose/polyethylene glycol (G-M-BC/PEG) was developed by integrating MXene (a two-dimensional material with good photothermal conversion performance) and graphene into a bacterial cellulose aerogel framework, subsequently impregnated with polyethylene glycol (PEG-2000). The film showed stable structure, efficient solar photothermal conversion and storage (SPCS), and improved mechanical properties. Under 1 sun irradiation, the optimized G-M-BC/PEG wearable film showed excellent SPCS performance, sustaining a temperature plateau of 38–40 °C for 10 min after the xenon lamp was switched off under 1 sun irradiation, with a leakage rate of only 5.32% after five cycles. By constructing a biomimetic sports human body model, the composite aerogel was shown to significantly elevate muscle surface temperature and effectively mitigate heat loss during the transition phase. In the warm-up effectiveness and sports performance tests, the wearable film improved 200 m sprint performance by 0.8% ± 0.4% (p = 0.039). It also maintained subjective thermal sensation during the warm-up transition phase, with no significant decline at 5 or 10 min after the warm-up and a significant decrease only at 15 min (p = 0.02), while thermal comfort remained stable, suggesting improved neuromuscular readiness. This research provided a novel strategy for the fabrication of advanced aerogel-based wearable devices aimed at precision thermal management and athletic performance optimization. Full article

The production and use of plastics have direct consequences on the environment, such as the greenhouse gas emissions (GHGs) they cause. Therefore, it is necessary to develop materials from renewable sources with a lower environmental impact to replace plastic. In this work, films with bioactive properties have been developed from cellulose nanofibers (CNFs) and natural phenolic compounds for food packaging applications. First, the optimization of the incorporation of three different natural phenolic compounds (tannic acid, p-coumaric acid, and acetosyringone) into nanocellulose was studied using a Box–Behnken design, with the phenols adsorbed by the nanocellulose as the output variable. Once the incorporation was optimized, films containing nanocellulose and phenolic compounds were produced and characterized. Tannic acid showed the best results with regard to the optical properties of the resulting films and achieved a complete blocking of UV-B radiation, as well as adding to nanocellulose antioxidant (4.32 mM TE/g film) and antibacterial capacity (log R of 6.6 ± 0.2 and 3.8 ± 0.1 for Staphylococcus aureus and Escherichia coli, respectively), making these films a promising material for use in contact with food as a packaging material, although more in-depth studies and measures are needed to make these films viable for use in food packaging. Full article

This study investigates the valorisation of Salicornia ramosissima agro-industrial by-product by using cellulose nanofibers (CNFs) extracted from this halophyte to reinforce chitosan-based films. The physical, mechanical, and thermal properties of chitosan films containing 0% (control), 1%, and 2% (w/w) CNF were evaluated. Films were produced by solvent casting with glycerol as a plasticiser. At the 2% CNF concentration, films exhibited a reduced moisture content and increased solubility in aqueous solutions. The water vapour transmission rate (WVTR) decreased as CNF content increased under constant humidity but increased at higher temperature and humidity. Control films were more transparent, yet CNF-reinforced films had higher tensile strength and Young’s modulus, reflecting greater stiffness. Maximum elongation at break decreased markedly with the addition of CNFs. SEM revealed that reinforced films had more heterogeneous, rougher surfaces, particularly at 2% CNF. Thermogravimetric analysis showed that 2% CNF adversely affected the thermal stability of the chitosan film. ATR-FTIR spectra indicated that CNF reinforcement protected against UV-induced degradation. Degradability tests in soil and seawater confirmed that the chitosan–CNF mixture preserved degradability, especially at 1% CNF. These findings demonstrate that reinforcing chitosan-based films with CNFs from S. ramosissima can improve functional properties and suggest the potential of this approach for biomaterials development in food packaging applications. Full article

Uranium is a critical raw material for the nuclear industry. Given the vast uranium reserves in seawater, the development of efficient adsorbents is central to extraction technologies. Polyamidoxime (PAO)-based adsorbents are widely utilized due to their high affinity for uranium; however, traditional PAO materials often suffer from low mechanical strength and poor recyclability. To address these limitations, this study utilized natural balsa wood as a substrate. A three-dimensional porous cellulose skeleton (DES-W) featuring high porosity, hydrophilicity, and retained mechanical strength was constructed by partially removing lignin using a deep eutectic solvent (DES). Subsequently, polyamidoxime was loaded onto the inner walls of the DES-W via vacuum impregnation, resulting in a polyamidoxime-functionalized wood-based adsorbent (PAO-WA). The results indicated that PAO-WA achieved an equilibrium adsorption capacity of 45.31 mg/g at pH 6.0 with an initial uranium concentration of 50 mg/L, representing a twofold increase compared to the unmodified DES-W. The adsorption kinetics and isotherms followed the pseudo-second-order and Langmuir models, respectively, suggesting a mechanism dominated by monolayer chemisorption. Mechanism analysis confirmed that uranyl ions were primarily captured via coordination with nitrogen and oxygen atoms in the amidoxime groups, with residual carboxyl groups in the wood contributing to the adsorption process. This work offers a novel strategy for developing efficient, environmentally friendly, and mechanically robust adsorbents for uranium extraction from seawater. Full article

Oxidized cellulose (OC) and oxidized regenerated cellulose (ORC) are bioabsorbable polysaccharide-based materials widely used in surgery for topical hemostasis. Beyond their established hemostatic role, increasing attention has been directed toward their potential antimicrobial activity, primarily attributed to local acidification following carboxyl group dissociation. Discussing the possible implications of the antibacterial properties of OC/ORC in veterinary surgical practice, this review critically examines the existing evidence. In vitro studies show that viable bacterial counts are significantly reduced in both Gram-positive and Gram-negative pathogens, including antibiotic-resistant strains. Historical in vivo animal models further support a reduction in bacterial recovery in contaminated tissues treated with OC. However, contemporary veterinary clinical trials specifically evaluating surgical site infection (SSI) outcomes remain limited. Documented limitations include variability in formulation, quantity-dependent degradation kinetics, and the potential for foreign body reactions when excessive material is retained. Current evidence suggests that OC may provide adjunctive antimicrobial effects under controlled experimental conditions, primarily in vitro and in standardized animal models, but these properties should be interpreted with caution, and its role should be integrated within comprehensive infection prevention strategies rather than considered a substitute for established perioperative protocols. Full article

Expanded polystyrene (EPS) waste is a major environmental concern, yet practical routes to upgrade it into higher value-added materials remain limited. Here, post-consumer EPS was dissolved in ethyl acetate and solvent-cast into films containing cellulose nanocrystals (CNCs) and a sunflower oil. Three formulations were produced: F-EPS (100% EPS), F-EPS + CEL (80% EPS/20% CNC), and F-EPS + CEL + OIL (80% EPS/15% CNC/5% oil). CNC markedly enhanced optical shielding, reducing transmittance at 400 nm from ≈58% (F-EPS) to ≈18% (CNC containing films). All films remained hydrophobic, showed negligible water uptake, and exhibited low mass loss after 30 days of accelerated weathering ($\Delta M=1$–$3\%$). Tensile testing showed that F-EPS had the highest UTS and elongation at break (10.0 ± 0.6 MPa and 10.5 ± 0.4%), whereas adding cellulose increased the elastic modulus (249.5 ± 29.0 MPa to 358.4 ± 64.8 MPa) but reduced UTS and elongation (8.2 ± 0.2 MPa and 5.4 ± 2.5%). Oil addition led to a further reduction in UTS and elongation (6.2 ± 0.4 MPa and 3.6 ± 0.0%), while the modulus returned to a value statistically similar to neat F-EPS. FTIR and XRD confirmed preservation of the EPS chemical fingerprint and a predominantly amorphous structure ($2\theta \approx 20$–30°). Overall, EPS + CNC + OIL films combine hydrophobicity, UV-screening, and elastic modulus similar to neat F-EPS, supporting their use as moisture-resistant, UV screening protective topcoats for non-food-contact paperboard packaging. Full article

Improving the interfacial compatibility between cellulose and poly(butylene adipate-co-terephthalate) (PBAT) is critical for enhancing the performance of PBAT-based composites. Here, microcrystalline cellulose (MCC) was homogeneously silanized at the molecular chain level using t-hexyldimethylchlorosilane (TDMS-Cl) as the modifier, yielding t-hexyldimethylsilylated cellulose (TDMS-Cell). TDMS-Cell/PBAT composite films were then prepared by solution blending and casting in tetrahydrofuran (THF). Structural characterizations confirmed the successful grafting of TDMS-Cl onto cellulose chains, resulting in TDMS-Cell with a degree of substitution of approximately 2. Microstructural observations combined with thermal analysis revealed that TDMS-Cell exerted a dual effect on the crystallization behavior of PBAT: it acted as a heterogeneous nucleating agent that increased the crystallization temperature, while the pronounced steric hindrance simultaneously suppressed crystal growth. Mechanical testing showed that simultaneous strengthening and toughening were achieved at an optimal TDMS-Cell loading of 3–5 wt%. Specifically, the tensile strength increased from ~16 MPa for neat PBAT to 21 MPa (31.25% improvement), and the elongation at break increased from ~700% to 964% (37.7% improvement). In addition, the incorporation of an appropriate amount of TDMS-Cell effectively enhanced the surface hydrophobicity of the composite films. At higher filler loading, however, solvent evaporation-induced phase separation led to self-aggregation of TDMS-Cell, which in turn deteriorated both the mechanical properties and surface hydrophobicity of the composites. Overall, this work systematically elucidates the structure–property relationships of silanized cellulose/PBAT composites in a homogeneous solution system, providing a rational basis for interfacial design and property optimization of PBAT/biomass-based composite materials. The prepared TDMS-Cell/PBAT composite films with balanced mechanical strength, tunable crystallization behavior, and improved surface hydrophobicity exhibit great potential for practical applications in high-performance flexible packaging materials, functional film substrates, lightweight composite structural components, and tunable hydrophobicity coating substrates. Full article

This research investigates novel polymeric composite materials made from recycled polyolefin and waste plant biomass (poplar seeds and vegetable peels), which have potential applications in the relatively unexplored field of electrical insulation. For composites made from poplar seeds with low density polyethylene matrix, the structure appears more uniform, even with increased biomass content, in contrast to those utilizing high density polyethylene matrix, which displays notable heterogeneous areas where the polymer appears separated from the fibrous network at higher biomass levels. Concerning the composites of vegetable peels with high density polyethylene matrix, the fragments of vegetable peels are clearly recognizable, and their bond to the polymer matrix appears weaker. When incorporating vegetable peels into the polypropylene matrix, it results in a better distribution of the vegetable peel fragments within the polymer matrix, as well as enhanced structural homogeneity. Overall, the incorporation of biomass reduces the Shore hardness measurement for every polymer matrix. Regarding tear resistance, the inclusion of biomass reduces the values only for low density polyethylene with poplar seeds. For both high density polyethylene and polypropylene, regardless of the biomass type, the property seems to enhance marginally with the addition of biomass. The primary advantage of utilizing these composites is that their water absorption rate is at least twice as low as that of transformer board, while still offering a similar capacity for absorbing transformer oil. All composite types exceeded the minimum required threshold of 70 °C for service exposure, and adhered to insulation class A, similar to cellulose-based insulations. The addition of cellulose to polyolefin composites appears to slightly improve their breakdown strength. The conductivity for this type of composite is at least three times lower than that of cellulose insulation materials, rendering them beneficial for applications in electrical engineering as potential substitutes for cellulose-based materials in multiple electrical insulation uses, e.g., for insulating low voltage electrical machines, as well as serving as a substitute for pressboard in transformers. Additionally, their thermoplastic properties offer enhanced processing versatility, opening up new opportunities for electrical engineering technology, especially with regard to electrical insulation recyclability in the context of a circular economy. Full article

Microplastics (MPs) and microfibres (MFs) are widespread contaminants that are found in natural environments worldwide. Although their presence has been documented in Arctic snow, sea ice and marine systems, data on their occurrence in Greenland glacier surface ice remain limited. Because of their small size, persistence, and mobility, MPs and MFs pose significant risks to both habitats and species, reaching even the most remote areas. Monitoring these environments is crucial for assessing the extent of pollution, while dissemination activities are essential for transferring scientific knowledge to local communities and fostering active engagement in adopting sustainable behaviours. A preliminary survey was conducted on a glacier in Greenland, collecting samples along the routes travelled by the Extreme E staff during the electric off-road racing series expedition in the region. Preliminary results confirmed the presence of MPs and MFs in the study area with high abundances. Fibrous and small-sized microparticles were the most prevalent types detected. The most common synthetic material was polyethylene terephthalate (PET), while natural and regenerated MFs were predominantly cellulosic. A deeper understanding of MP and MF contamination in extreme environments was achieved, highlighting the importance of environmental education and public awareness as key tools in mitigating pollution and promoting sustainable strategies. The integration of different sectors can synergistically promote sustainability efforts and address the urgent challenges of climate change and environmental pollution. Full article

Nanocellulose materials (CNMs), encompassing cellulose nanocrystals (CNCs), cellulose nanofibrils (CNFs), and bacterial nanocellulose (BNC), have emerged as a versatile and sustainable class of bio-based nanomaterials with significant promise for applications in mechanical engineering. This review systematically examines the processing of nanocellulose via mechanical, chemical, and enzymatic routes, alongside surface modification strategies that enhance performance and address scalability challenges. A principal advantage of CNMs lies in their exceptional mechanical properties, including superior strength, stiffness, and toughness, which position them as high-performance, sustainable reinforcement agents for advanced composites. Beyond mechanical reinforcement, CNMs exhibit a suite of functional properties critical for engineering design, such as thermal stability, tunable conductivity, effective gas/moisture barrier performance, and improved tribological behavior. These characteristics enable their use in diverse high-value applications, including lightweight composites, protective coatings, energy storage devices, sensors, actuators, and intelligent material systems. Furthermore, the inherent renewability, biodegradability, and recyclability of nanocellulose align closely with the principles of a circular economy and green engineering. However, the successful integration of CNMs into mainstream manufacturing requires overcoming key challenges. These include the energy intensity of certain production processes, inherent moisture sensitivity, long-term stability under operational conditions, and compatibility with established industrial techniques. Life-cycle analyses reveal important environmental trade-offs that must be navigated. Overall, nanocellulose represents a renewable, multi-functional material platform whose unique combination of mechanical performance, functional versatility, and environmental benefits is poised to drive innovation in next-generation engineering materials. Full article

This work explores, for the first time, a novel strategy for the preparation of polymer inclusion membranes (PIMs) based on their deposition onto porous supporting substrates, introducing the concept of supported PIMs as a reagent-efficient alternative to conventional free-standing membranes. The approach aims to improve the sustainability of PIM fabrication by significantly reducing the amount of polymer and extractant required while preserving membrane functionality. PIMs were prepared using the two most widely employed base polymers, cellulose triacetate (CTA) and poly(vinyl chloride) (PVC), with Aliquat 336 as extractant. The total reagent consumption was reduced to half of the conventional formulation for CTA-based membranes and to one quarter for PVC-based membranes. Two porous supports with contrasting physicochemical properties—a hydrophilic cellulose filter paper and a hydrophobic Durapore^® PVDF membrane—were investigated. The supported membranes were characterized by contact angle measurements, SEM, FTIR, and TGA, confirming the successful integration of the PIM phase onto the porous supports without chemical alteration. Arsenate (As(V)) transport, preconcentration, and membrane reusability were evaluated. CTA-based supported PIMs exhibited transport efficiencies of approximately 90–95%, comparable to free-standing PIMs, whereas PVC-based systems showed a stronger dependence on membrane loading. Notably, CTA-based Durapore^®–PIMs retained around 70% transport efficiency after three reuse cycles. These results demonstrate the feasibility of supported PIMs as a strategy for reducing membrane material consumption while preserving functional performance. Full article

The rising demand for clean water has reinforced the importance of thin-film composite TFC polyamide membranes in desalination and wastewater treatment. While improvements often target the selective layer, these can sometimes reduce stability or selectivity. An alternative approach is to tailor the porous support, particularly through the incorporation of nanomaterials such as metal oxides, carbon-based nanomaterials, metal–organic frameworks (MOFs), zeolites, and cellulose-based materials, to improve overall membrane performance. The modification of membrane substrates through the incorporation of nanofillers has demonstrated notable advantages, including enhanced hydrophilicity, improved mechanical stability, and increased porosity. These improvements collectively contribute to higher permeability, reduced internal concentration polarization and enhanced separation performance in FO, NF, and RO applications. The review starts by clearly distinguishing substrate modification, in which nanomaterials are localized in the porous support, from interlayer modification, which involves constructing a distinct layer between the support and selective layer. This concise review highlights current developments in the nanomaterial-based support modification of polyamide TFC membranes; it summarizes nanomaterials selections, incorporation techniques, and resulting property changes. Current challenges and potential research opportunities are also discussed. Full article

In this study, the commercial biobased cellulose–acetate-based blend ARBOBLEND^® 4655V was analysed with regard to its property changes after multiple mechanical recycling at three different processing temperatures (170 °C, 190 °C, and 210 °C). The results demonstrate that the material properties evolve in a distinct manner across the recycling cycles, depending on the processing temperature. While no relevant changes in the zero-shear viscosity, rheologically indicated average molecular weight, or thermal and mechanical properties were observed at 170 °C, moderate changes were observed at 190 °C, in particular an increase in the zero-shear viscosity and rheological indications of an increased average molecular weight, a broadening of the molecular weight distribution, and a change in crystallisation behaviour over the recycling passes. At 210 °C, a marked reduction in the zero-shear, rheological indications of a decreased average molecular weight, and a narrowing of the molecular weight distribution were observed. These rheology-based structural changes had an effect on the mechanical properties, such as the impact strength, the elongation at break, and the elongation at ultimate tensile stress, which were found to decrease with an increasing number of recycling passes. The study suggests that the processing temperature exerts a significant influence on the recycling behaviour of the cellulose–acetate-based blend ARBOBLEND^® 4655V. It is evident that even minor fluctuations in temperature can result in substantial changes to the physical, thermal, and mechanical properties of biopolymers. The findings underline the necessity of conducting recycling-related investigations with the processing temperature as a critical factor, particularly for temperature-sensitive materials such as cellulose–acetate-based compounds. Full article

The synthesis of sustainable and promising biomaterials for biomedical applications has recently gained increasing importance. In this study, a hybrid hydrogel was synthesized from empty palm date bunches through the blending of natural (carboxymethyl cellulose) and synthetic polymers (polyvinyl alcohol, polyvinylpyrrolidone) using both traditional and microwave-assisted methods. The aim was to investigate the ability of the hydrogel to immobilize and control the release of bovine serum albumin (BSA), a model protein widely used in pharmaceutical biotechnology. The effect of key parameters such as pH, temperature and hydrogel dosage on protein immobilization was investigated. Optimal results were observed at a pH of 7.4, a temperature of 37 °C and a dosage of 2 g/L—such conditions are very close to the human physiological environment. Kinetic and isotherm models indicated that the immobilization process adhered to pseudo-second-order kinetics and was well-fitted to the Langmuir isotherm. This implied a monolayer adsorption mechanism on a comparatively homogeneous surface. The release studies demonstrated a time-dependent and diffusion-controlled trend, with BSA attaining equilibrium release at 150 min. Overall, the results underline the potential of the microwave-synthesized plant-based hydrogel as a promising material for controlled drug delivery and other biomedical applications due to its efficiency and sustainability. Full article