Cellulose最新文献

The interfacial topography of biomaterials has been identified as a major biophysical regulator of cell behavior and function, a role played through the interplay with biochemical cues. In this work, we demonstrate the potential of laser as a versatile technology for the direct fine-tuning of the topography of Bacterial nanocellulose (BNC) with bioinspired topographies and micropatterns on a cell size scale. Two lasers were used, with different wavelengths—IR (CO₂, 10600 nm) and UV (tripled Nd: YVO₄, 355 nm) —attempting to reproduce the Pitcher-plant topography and to create cell-contact guidance patterns, respectively. Different topographies with parallel grooves featuring a 20–300 μm period were generated on the BNC surface with high fidelity and reliability of the generated microstructures, as demonstrated by 3D optical profilometry and scanning electron microscopy. Moreover, it was demonstrated by X-ray photoelectron spectroscopy that laser processing does not result in detectable chemical modification of BNC. The developed anisotropic microstructures can control cell behavior, particularly regarding morphology, alignment, and spatial distribution. Thus, this proof-of-concept study on the high-resolution laser patterning of BNC opens new perspectives for the development of cell-modulating laser-engineered BNC interfaces, scaffolds, and other advanced medical devices, which can potentially broaden the application of BNC in the biomedical field.

This work explored whether partial cellulose bioconversion with fungal mycelium can improve the properties of cellulose fibre-based materials. We demonstrate an efficient approach for producing cellulose-mycelium composites utilizing several cellulosic matrices and show that these materials can match fossil-derived polymeric foams on water contact angle, compression strength, thermal conductivity, and exhibit selective antimicrobial properties. Fossil-based polymeric foams commonly used for these applications are highly carbon positive, persist in soils and water, and are challenging to recycle. Bio-based alternatives to synthetic polymers could reduce GHG emissions, store carbon, and decrease plastic pollution. We explored several fungal species for the biofabrication of three kinds of cellulosic-mycelium composites and characterized the resulting materials for density, microstructure, compression strength, thermal conductivity, water contact angle, and antimicrobial properties. Foamed mycelium-cellulose samples had low densities (0.058 – 0.077 g/cm³), low thermal conductivity (0.03 – 0.06 W/m∙K at + 10 °C), and high water contact angle (118 – 140°). The recovery from compression of all samples was not affected by the mycelium addition and varied between 70 and 85%. In addition, an antiviral property against active MS-2 viruses was observed. These findings show that the biofabrication process using mycelium can provide water repellency and antiviral properties to cellulose foam materials while retaining their low density and good thermal insulation properties.

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In modern society, with the rapid increase in energy consumption, there is a growing interest in the effective utilization of bio-resources. Biomass aerogels have considerable academic research value due to their eco-friendly attributes and renewable nature. In this work, sodium alginate (SA) and sodium lignosulfonate (SLS) are employed as the matrix, which are dually cross-linked with Ca²⁺ and bis[tetrakis(hydroxymethyl)phosphonium] sulfate (THPS). Subsequently, a well-formed aerogel (CA-SP) is obtained through the lyophilization process. The formed dual crosslinking network and the “egg-box” structure endow the CA-SP aerogel with superior flame retardancy and thermal insulation properties, as evidenced by a limiting oxygen index value of 40.8%, achievement of the UL94 V-0 rating and low total heat release (1.35 MJ·m⁻²). Moreover, the THPS simultaneously endows the SA-SP aerogel with excellent flame retardancy and antimicrobial effect. The exceptional flame retardancy, smoke suppression capabilities, and antimicrobial effects of the CA-SP aerogel expand its prospects for application.

The field of bioactive textile materials holds great potential for the advancement of functional textiles. One of the commonly studied bioactive textile materials is the integration of antimicrobial properties into the textile. The present work was aimed at the process development of scouring of greige cotton fabric and absorption of antiseptic solution by the scoured cotton in a single bath. Scouring was carried out to remove the wax barrier from the greige cotton fabric's surface using the cutinase enzyme without damaging the fiber's core. To increase its stability and make it reusable, the cutinase enzyme was immobilized onto the magnetic nanoparticles. The effect of cotton bioscouring on its dyeability with methylene blue dye was examined. Results revealed that bioscoured cotton fabric showed uniform and enhanced dye absorption as compared to conventionally scoured cotton fabric. Furthermore, bioscoured cotton fabric was finished with 10% betadine solution to develop antibacterial characteristics. Single bath bioscouring of greige cotton and absorption of betadine solution on bioscoured cotton fabric was conducted to reduce the water, energy and time consumption. To check the effectiveness of the single bath process, fabrics were assessed for their effectiveness against Gram-positive bacteria (S. aureus, MRSA) and Gram-negative bacteria (E. coli and P. aeruginosa) using the disc diffusion method. Results showed the formation of an inhibition zone of bacterial growth around the test cotton fabric.

The production of yarns and synthetic fibers is of great importance for numerous industrial sectors, such as the textile, composite material, biomedical, and civil construction industries. The utilization of cellulose microfibrils (CNFs) for filament production still requires further research, given the challenges associated with the coagulation process. Extensive research efforts have been dedicated to the development of materials that can be combined with CNFs to improve coagulation. This study aimed to develop an acetone spinning method to produce filaments from CNFs combined with xanthan (XG) and guar (GG) gums. Three types of filament architecture were tested: monocomponent (MONO), bicomponent (BI), and mixed component (MIX). XG filaments were evaluated at three coagulation times (90, 120, and 150 s) and GG filaments at a single coagulation time (120 s). Morphological analysis showed that gums contributed to improving external structure. BI filaments were rounder, exhibited lower stress concentration, and showed the highest mechanical resistance after 120 s of coagulation (XG = 27.97 MPa, GG = 28.69 MPa). Water absorption tests showed that the developed filaments hold great potential as absorbent materials, representing an environmentally friendly alternative to synthetic polymer absorbents.

A microfluidic thread/paper-based analytical device (µTPAD) is of great significance in biomedical analysis and point-of-care diagnostics. Nevertheless, the research has not been done on the ion distribution on the thread and how it affects sensing so far. Inspired by the sweat stains on the clothes, a high-performance µTPAD based on the evaporation-induced ion enrichment is presented for glucose monitoring in salty solutions. In comparison to the multi-ply cotton thread, the single-ply cotton thread exhibits the most significant ion-enrichment capability at the rear segment, which could be attributed to the balance between the water evaporation and the solution replenishment in the thread. The salts accumulated at the rear segment could increase the ionic strength of the solution passed through the thread, promoting the colorimetric reaction on the paper-based sensing unit. The single-ply thread with strong ion-enrichment capability was integrated with a paper-based glucose sensor to prepare a µTPAD for highly sensitive glucose detection in both PBS and artificial sweat (-0.673µM⁻¹ in PBS and − 0.253 µM⁻¹ in artificial sweat). Moreover, the system could detect glucose in human sweat samples with high accuracy and precision. This work may provide a strategy to prepare a highly sensitive µTPAD for precise analysis of substances in bio-fluids, particularly human sweat.

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The lithium-sulfur battery (LSB) is a highly promising energy storage system with merits of exceptional theoretical specific capacity and energy density. However, challenges including insufficient sulfur conductivity, volume expansion, and the polysulfide shuttle effect result in rapid capacity decay and limited cycle life of the LSB, which significantly hinders its development. Inspired by the structure and forming process of paper, a fiber double network skeleton was constructed using flexible pulp fiber (PF) and highly conductive carbon fiber (CF). Following the principles of wet end chemistry in papermaking, MXene nanosheets with high adsorption and catalytic capacity for polysulfides were self-assembled on the surfaces of PF and CF to fabricate composite paper-based materials. The interwoven mesh of PF exhibited strong binding force and stable structure, providing support and protection for the CF interwoven mesh, resulting in a composite material with abundant porosity and excellent structural stability. Moreover, the CF interweaving network combined with an overlaid MXene interweaving network established an effective three-dimensional conductive pathway. When utilized as a self-supporting cathode in LSB, this composite paper-based material demonstrated outstanding cyclic stability. Under conditions of sulfur load at 2.3 mg·cm⁻² and discharge at 0.2 C, the specific discharge capacity remained at 952 mAh·g⁻¹ after 200 cycles with a capacity retention rate reaching 95.4%. The CF/PF@Mxene (CPCMX) also exhibited excellent tensile strength measured at 7.19 MPa while maintaining exceptional flexibility and electrolyte wettability. This research presents a highly promising solution for advancing the development of LSB with superior cycle stability.

The development of effective drug delivery systems is crucial for improving the efficacy of cancer drugs, in order to overcome the issues of low drug loading and drug burst release. Nanocellulose composite aerogel was prepared as a drug carrier for 5-fluorouracil, which had the advantages of three-dimensional network structures, high porosity and good biocompatibility, and its loading capacity was much higher than that of other bio-based drug carriers. Fourier-transform infrared, scanning electron microscopy, X-ray photoelectron spectroscopy, cytotoxicity analysis, and other analytical techniques were used to analyse the physical and chemical structures of nanocellulose composite aerogels. The analysis revealed that the introduction of β-cyclodextrin and sodium hyaluronate led to good compressibility, rich network structure, and abundant adsorption active sites of the nanocellulose composite aerogel, which was more suitable as a drug carrier. The maximum amount of 5-fluorouracil on the nanocellulose composite aerogel through coating and hydrogen bonding reached 486.93 mg/g. The drug release curves of the nanocellulose composite aerogels depended on pH and conformed to the first-order kinetic model and Korsmeyer-Peppas model. Nanocellulose composite aerogels exhibited a high loading capacity and controllable release of 5-fluorouracil, with great potential for biomedical applications.

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A promising method for cancer therapy is the coating of magnetic nanoparticles with carboxy methylcellulose. In a research project, hydroalcoholic extract of Cinnamomum camphora leaves was used to demonstrate the production of magnetic nanoparticles (MNPs); MNPs were coated with carboxymethyl cellulose to form carboxymethyl cellulose-coated magnetic nanoparticles (CMNPs)were formed. Preliminary phytochemical screening of C. camphora confirmed the presence of flavonoids, carbohydrates, phenolic compounds, and proteins. Phenolics 280.59 (mg/g), flavonoids 15.46 (mg/g), proteins 1.9 (mg/mL) and total carbohydrates 293.80 (mg/g) were all quantified. To confirm the formation of MNPs and CMNPs, UV–visible (UV–vis) spectroscopy, Fourier transform infrared (FT-IR) spectroscopy, X-ray diffraction (XRD), transmission electron microscopy (TEM), and X-ray photoelectron spectroscopy (XPS) were used. Peaks were observed at 232 nm and 240 nm, respectively. The largest absorption peaks were observed in MNPs and CMNPs, respectively. The particles were spherical in shape and less than 10 (nm) in diameter. The potential scavenging activity of biosynthesized MNPs and CMNPs was evaluated by the ABTS and DPPH assays, and the inhibition values IC₅₀ were 141.3 ± 3.0 and 61.67 ± 2.5 (µg/mL) for ABTS and 176.1 ± 4.0 and 70.92 ± 3.0 (µg/mL) for DPPH, respectively (p ≤ 0.05). Furthermore, the cytotoxicity test results showed that the HCT-116 human colon cancer cell line had the lowest IC₅₀ value of 20 (µg/mL) for CMNP, followed by the HepG2 hepatocellular carcinoma cell line with an IC₅₀ value of 33 (µg/mL) for CMNP, indicating that the cytotoxic effect on colon cancer cells is stronger than on liver cancer cells. Molecular docking studies have revealed that CMNPs target and bind to apoptotic protein, enhancing their bioactivity and cytotoxic effects on cancer cells. Furthermore, our findings suggest that the induction of apoptosis may be responsible for the anticancer effects of CMNPs.

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Paper is the largest renewable industrial substrate produced for various applications and can be recycled by disintegrating the fibers and reforming the paper. Paper and its fiber constituents lack functions such as electrical conductivity and papermaking itself has not been used for producing electronic devices. In this work, we show a potential industrially viable route for introducing cationic charges on the cellulose fibers and subsequently show how the adsorption of negatively charged ionically and electrically conductive materials onto these fibers from aqueous media can be applied at time scales relevant to industrial papermaking. This results in electroactive fibers, that can subsequently be used to prepare electroactive papers using standard papermaking procedures. Since fibers in the paper can selectively be coated with different active materials, various functions can be added into the paper. To demonstrate applications, we prepared electroactive papers using fibers with adsorbed carbon nanotubes (CNTs) and conducting polymers. We achieved conductivity of 21 S/m with only 1wt% CNT. We also prepared papers with CNTs and black phosphorus, used as paper-based lithium, and sodium ion battery (free-standing) anodes. They delivered a specific capacity of 642 mA h g⁻¹ at 100 mA g⁻¹ after 3500 cycles with 99.5% columbic efficiency. Furthermore, we recycled the papers, and as the disintegration of the fibers did not lead to removal of the ionic or electroactive materials from the fiber surface, the recycled papers showed similar electrical and mechanical properties to the original papers. This opens the path for recyclable paper-based electronics.