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1.
Mol Biol Rep ; 51(1): 658, 2024 May 15.
Article in English | MEDLINE | ID: mdl-38748314

ABSTRACT

BACKGROUND: The formation of chronic wounds accounts for considerable costs in health care systems. Despite the several benefits of decellularized small intestinal submucosa (SIS) as an appropriate scaffold for different tissue regeneration, it has shortcomings such as lack of antibacterial features and inappropriate mechanical properties for skin tissue regeneration. We aimed to examine the efficacy and safety of decellularized SIS scaffold enhanced with cellulose acetate (CA) and silver (Ag) nanoparticles (NPs) for healing full-thickness wounds. METHODS AND RESULTS: The scaffolds were prepared by decellularizing bovine SIS and electrospinning CA/Ag nanoparticles and characterized using a transmission electron microscope (TEM), scanning electron microscope (SEM), tensile testing, and X-ray diffraction. In vivo evaluations were performed using full-thickness excisions covered with sterile gauze as the control group, SIS, SIS/CA, and SIS/CA/Ag scaffolds on the dorsum of twenty male Wistar rats divided into four groups randomly with 21-days follow-up. All in vivo specimens underwent Masson's trichrome (MT) staining for evaluation of collagen deposition, transforming growth factor-ß (TGF-ß) immunohistochemistry (IHC), and Haematoxylin Eosin (H&E) staining. The IHC and MT data were analyzed with the ImageJ tool by measuring the stained area. The TEM results revealed that Ag nanoparticles are successfully incorporated into CA nanofibers. Assessment of scaffolds hydrophilicity demonstrated that the contact angle of SIS/CA/Ag scaffold was the lowest. The in vivo results indicated that the SIS/CA/Ag scaffold had the most significant wound closure. H&E staining of the in vivo specimens showed the formation of epidermal layers in the SIS/CA/Ag group on day 21. The percentage of the stained area of MT and TGF-ß IHC staining's was highest in the SIS/CA/Ag group. CONCLUSION: The decellularized SIS/CA/Ag scaffolds provided the most significant wound closure compared to other groups and caused the formation of epidermal layers and skin appendages. Additionally, the collagen deposition and expression of TGF-ß increased significantly in SIS/CA/Ag group.


Subject(s)
Cellulose , Intestinal Mucosa , Intestine, Small , Metal Nanoparticles , Nanofibers , Rats, Wistar , Silver , Tissue Scaffolds , Wound Healing , Animals , Silver/chemistry , Cellulose/analogs & derivatives , Cellulose/chemistry , Wound Healing/drug effects , Metal Nanoparticles/chemistry , Rats , Nanofibers/chemistry , Tissue Scaffolds/chemistry , Intestinal Mucosa/metabolism , Male , Intestine, Small/metabolism , Cattle , Transforming Growth Factor beta/metabolism , Tissue Engineering/methods , Collagen
2.
Carbohydr Polym ; 337: 122112, 2024 Aug 01.
Article in English | MEDLINE | ID: mdl-38710545

ABSTRACT

The growing concerns on environmental pollution and sustainability have raised the interest on the development of functional biobased materials for different applications, including food packaging, as an alternative to the fossil resources-based counterparts, currently available in the market. In this work, functional wood inspired biopolymeric nanocomposite films were prepared by solvent casting of suspensions containing commercial beechwood xylans, cellulose nanofibers (CNF) and lignosulfonates (magnesium or sodium), in a proportion of 2:5:3 wt%, respectively. All films presented good homogeneity, translucency, and thermal stability up to 153 °C. The incorporation of CNF into the xylan/lignosulfonates matrix provided good mechanical properties to the films (Young's modulus between 1.08 and 3.79 GPa and tensile strength between 12.75 and 14.02 MPa). The presence of lignosulfonates imparted the films with antioxidant capacity (DPPH radical scavenging activity from 71.6 to 82.4 %) and UV barrier properties (transmittance ≤19.1 % (200-400 nm)). Moreover, the films obtained are able to successfully delay the browning of packaged fruit stored over 7 days at 4 °C. Overall, the obtained results show the potential of using low-cost and eco-friendly resources for the development of sustainable active food packaging materials.


Subject(s)
Cellulose , Food Packaging , Lignin , Lignin/analogs & derivatives , Nanocomposites , Nanofibers , Tensile Strength , Wood , Xylans , Food Packaging/methods , Lignin/chemistry , Nanocomposites/chemistry , Cellulose/chemistry , Cellulose/analogs & derivatives , Wood/chemistry , Nanofibers/chemistry , Xylans/chemistry , Antioxidants/chemistry , Fruit/chemistry
3.
J Mol Model ; 30(5): 156, 2024 May 02.
Article in English | MEDLINE | ID: mdl-38693294

ABSTRACT

CONTEXT: Due to their excellent biocompatibility and degradability, cellulose/spider silk protein composites hold a significant value in biomedical applications such as tissue engineering, drug delivery, and medical dressings. The interfacial interactions between cellulose and spider silk protein affect the properties of the composite. Therefore, it is important to understand the interfacial interactions between spider silk protein and cellulose to guide the design and optimization of composites. The study of the adsorption of protein on specific surfaces of cellulose crystal can be very complex using experimental methods. Molecular dynamics simulations allow the exploration of various physical and chemical changes at the atomic level of the material and enable an atomic description of the interactions between cellulose crystal planes and spider silk protein. In this study, molecular dynamics simulations were employed to investigate the interfacial interactions between spider silk protein (NTD) and cellulose surfaces. Findings of RMSD, RMSF, and secondary structure showed that the structure of NTD proteins remained unchanged during the adsorption process. Cellulose contact numbers and hydrogen bonding trends on different crystalline surfaces suggest that van der Waals forces and hydrogen bonding interactions drive the binding of proteins to cellulose. These findings reveal the interaction between cellulose and protein at the molecular level and provide theoretical guidance for the design and synthesis of cellulose/spider silk protein composites. METHODS: MD simulations were all performed using the GROMACS-5.1 software package and run with CHARMM36 carbohydrate force field. Molecular dynamics simulations were performed for 500 ns for the simulated system.


Subject(s)
Cellulose , Hydrogen Bonding , Molecular Dynamics Simulation , Silk , Spiders , Cellulose/chemistry , Spiders/chemistry , Animals , Silk/chemistry , Adsorption , Protein Binding , Fibroins/chemistry
4.
Int J Mol Sci ; 25(9)2024 May 02.
Article in English | MEDLINE | ID: mdl-38732196

ABSTRACT

The investigation of functional materials derived from sustainable and eco-friendly bioresources has generated significant attention. Herein, nanocomposite films based on chiral nematic cellulose crystals (CNCs) were developed by incorporating xylose and biocompatible ZnO nanoparticles (NPs) via evaporation-induced self-assembly (EISA). The nanocomposite films exhibited iridescent color changes that corresponded to the birefringence phenomenon under polarized light, which was attributed to the formation of cholesteric structures. ZnO nanoparticles were proved to successfully adjust the helical pitches of the chiral arrangements of the CNCs, resulting in tunable optical light with shifted wavelength bands. Furthermore, the nanocomposite films showed fast humidity and ethanol stimuli response properties, exhibiting the potential of stimuli sensors of the CNC-based sustainable materials.


Subject(s)
Cellulose , Ethanol , Humidity , Nanoparticles , Zinc Oxide , Cellulose/chemistry , Zinc Oxide/chemistry , Ethanol/chemistry , Nanoparticles/chemistry , Nanocomposites/chemistry
5.
Molecules ; 29(9)2024 Apr 29.
Article in English | MEDLINE | ID: mdl-38731545

ABSTRACT

Functional Lyocell fibers gain interest in garments and technical textiles, especially when equipped with inherently bioactive features. In this study, Lyocell fibers are modified with an ion exchange resin and subsequently loaded with copper (Cu) ions. The modified Lyocell process enables high amounts of the resin additive (>10%) through intensive dispersion and subsequently, high uptake of 2.7% Cu throughout the whole cross-section of the fiber. Fixation by Na2CO3 increases the washing and dyeing resistance considerably. Cu content after dyeing compared to the original fiber value amounts to approx. 65% for reactive, 75% for direct, and 77% for HT dyeing, respectively. Even after 50 household washes, a recovery of 43% for reactive, 47% for direct and 26% for HT dyeing is proved. XRD measurements reveal ionic bonding of Cu fixation inside the cellulose/ion exchange resin composite. A combination of the fixation process with a change in Cu valence state by glucose/NaOH leads to the formation of Cu2O crystallites, which is proved by XRD. Cu fiber shows a strong antibacterial effect against Staphylococcus aureus and Klebsiella pneumonia bacteria, even after 50 household washing cycles of both >5 log CFU. In nonwoven blends with a share of only 6% Cu fiber, a strong antimicrobial (CFU > log 5) and full antiviral effectiveness (>log 4) was received even after 50 washing cycles. Time-dependent measurements already show strong antiviral behavior after 30 s. Further, the fibers show an increased die off of the fungal isolate Candida auris with CFU log 4.4, and nonwovens made from 6% Cu fiber share a CFU log of 1.7. Findings of the study predestines the fiber for advanced textile processing and applications in areas with high germ loads.


Subject(s)
Anti-Bacterial Agents , Antifungal Agents , Antiviral Agents , Copper , Antifungal Agents/pharmacology , Antifungal Agents/chemistry , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Antiviral Agents/pharmacology , Antiviral Agents/chemistry , Copper/chemistry , Copper/pharmacology , Cellulose/chemistry , Cellulose/pharmacology , Staphylococcus aureus/drug effects , Textiles , Microbial Sensitivity Tests , Klebsiella pneumoniae/drug effects , Lignin/chemistry , Lignin/pharmacology , Humans
6.
Molecules ; 29(9)2024 Apr 30.
Article in English | MEDLINE | ID: mdl-38731558

ABSTRACT

Given the widespread prevalence of viruses, there is an escalating demand for antimicrobial composites. Although the composite of dialdehyde cellulose and silver nanoparticles (DAC@Ag1) exhibits excellent antibacterial properties, its weak mechanical characteristics hinder its practical applicability. To address this limitation, cellulose nanofibers (CNFs) were initially ammoniated to yield N-CNF, which was subsequently incorporated into DAC@Ag1 as an enhancer, forming DAC@Ag1/N-CNF. We systematically investigated the optimal amount of N-CNF and characterized the DAC@Ag1/N-CNF using FT-IR, XPS, and XRD analyses to evaluate its additional properties. Notably, the optimal mass ratio of N-CNF to DAC@Ag1 was found to be 5:5, resulting in a substantial enhancement in mechanical properties, with a 139.8% increase in tensile elongation and a 33.1% increase in strength, reaching 10% and 125.24 MPa, respectively, compared to DAC@Ag1 alone. Furthermore, the inhibition zones against Escherichia coli and Staphylococcus aureus were significantly expanded to 7.9 mm and 15.9 mm, respectively, surpassing those of DAC@Ag1 alone by 154.8% and 467.9%, indicating remarkable improvements in antimicrobial efficacy. Mechanism analysis highlighted synergistic effects from chemical covalent bonding and hydrogen bonding in the DAC@Ag1/N-CNF, enhancing the mechanical and antimicrobial properties significantly. The addition of N-CNF markedly augmented the properties of the composite film, thereby facilitating its broader application in the antimicrobial field.


Subject(s)
Cellulose , Escherichia coli , Metal Nanoparticles , Silver , Staphylococcus aureus , Silver/chemistry , Metal Nanoparticles/chemistry , Escherichia coli/drug effects , Staphylococcus aureus/drug effects , Cellulose/chemistry , Cellulose/analogs & derivatives , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Nanofibers/chemistry , Nanocomposites/chemistry , Microbial Sensitivity Tests , Anti-Infective Agents/chemistry , Anti-Infective Agents/pharmacology , Spectroscopy, Fourier Transform Infrared
7.
Biomacromolecules ; 25(5): 3076-3086, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38634234

ABSTRACT

Despite the wide range of analytical tools available for the characterization of cellulose, the in-depth characterization of inhomogeneous, layered cellulose fiber structures remains a challenge. When treating fibers or spinning man-made fibers, the question always arises as to whether the changes in the fiber structure affect only the surface or the entire fiber. Here, we developed an analysis tool based on the sequential limited dissolution of cellulose fiber layers. The method can reveal potential differences in fiber properties along the cross-sectional profile of natural or man-made cellulose fibers. In this analytical approach, carbonyl groups are labeled with a carbonyl selective fluorescence label (CCOA), after which thin fiber layers are sequentially dissolved with the solvent system DMAc/LiCl (9% w/v) and analyzed with size exclusion chromatography coupled with light scattering and fluorescence detection. The analysis of these fractions allowed for the recording of the changes in the chemical structure across the layers, resulting in a detailed cross-sectional profile of the different functionalities and molecular weight distributions. The method was optimized and tested in practice with LPMO (lytic polysaccharide monooxygenase)-treated cotton fibers, where it revealed the depth of fiber modification by the enzyme.


Subject(s)
Cellulose , Cellulose/chemistry , Cotton Fiber , Chromatography, Gel/methods
8.
Biomacromolecules ; 25(5): 3018-3032, 2024 May 13.
Article in English | MEDLINE | ID: mdl-38648261

ABSTRACT

Different cellulose nanocrystal (CNC) forms (dried vs never-dried) can lead to different degrees of CNC reassembly, the formation of nanofibril-like structures, in nanocomposite latex-based pressure-sensitive adhesive (PSA) formulations. CNC reassembly is also affected by CNC sonication and loading as well as the protocol used for CNC addition to the polymerization. In this study, carboxylated CNCs (cCNCs) were incorporated into a seeded, semibatch, 2-ethylhexyl acrylate/methyl methacrylate/styrene emulsion polymerization and cast as pressure-sensitive adhesive (PSA) films. The addition of CNCs led to a simultaneous increase in tack strength, peel strength, and shear adhesion, avoiding the typical trade-off between the adhesive and cohesive strength. Increased CNC reassembly resulted from the use of dried, redispersed, and sonicated cCNCs, along with increased cCNC loading and addition of the cCNCs at the seed stage of the polymerization. The increased degree of CNC reassembly was shown to significantly increase the shear adhesion by enhancing the elastic modulus of the PSA films.


Subject(s)
Adhesives , Cellulose , Latex , Nanoparticles , Cellulose/chemistry , Adhesives/chemistry , Nanoparticles/chemistry , Latex/chemistry , Polymerization , Nanocomposites/chemistry , Pressure
9.
Bioresour Technol ; 401: 130728, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38657827

ABSTRACT

This study investigated a lignin-first approach to produce furan-modified lignin from sugarcane bagasse (SB), rice hull (RH), and sunn hemp biomass (SHB) using 5 methylfurfural (MF) and 5 methul-2-furanmethanol (MFM). The reaction time (5 h) was selected based on the delignification of SB using methanol and Ru/C catalyst which yielded the highest hydroxyl content. Delignification of SB with various MF weight ratios (1:1, 1:2, 1:3, 2:1, and 3:1) revealed that 1:1 and 2:1 ratios produced the highest hydroxyl content (7.7 mmol/g) and bio-oil yield (23.2 % wt% total weight). Further exploration identified that RH and MF at 1:1 ratio and SHB and MF at a 2:1 ratio produced the highest hydroxyl content (13.0 mmol/g) and bio-oil yield (31.6 % wt% tot. weight). This study developed a one-step method to extract and modify lignin with furan compounds simultaneously while opening new avenues for developing value-added products.


Subject(s)
Furans , Lignin , Lignin/chemistry , Furans/chemistry , Biomass , Agriculture , Oryza/chemistry , Cellulose/chemistry , Saccharum/chemistry , Biofuels , Waste Products , Cannabis/chemistry
10.
Bioresour Technol ; 401: 130744, 2024 Jun.
Article in English | MEDLINE | ID: mdl-38677384

ABSTRACT

Paper sludge biomass represents an underutilized feedstock rich in pulped and processed cellulose which is currently a waste stream with significant disposal cost to industry for landfilling services. Effective fractionation of the cellulose from paper sludge presents an opportunity to yield cellulose as feedstock for value-added processes. A novel approach to cellulose fractionation is the sidehill screening system, herein studied at the pilot-plant scale. Composition analysis determined ash removal and carbohydrate retention of both sidehill and high-performance benchtop screening systems. Sidehill screening resulted in greater carbohydrates retention relative to benchtop screening (90% vs 66%) and similar ash removal (95% vs 98%). Techno-economic analysis for production of sugar syrup yielded a minimum selling price of $331/metric ton of sugar syrup including disposal savings, significantly less than a commercial sugar syrup without fractionation. Sensitivity analysis showed that screening conditions played a significant role in economic feasibility for cellulosic yield and downstream processes.


Subject(s)
Biomass , Cellulose , Paper , Sewage , Pilot Projects , Cellulose/chemistry , Chemical Fractionation
11.
Int J Biol Macromol ; 267(Pt 1): 131406, 2024 May.
Article in English | MEDLINE | ID: mdl-38582472

ABSTRACT

Starch and plant fibers are abundant natural polymers that offer biodegradability, making them potential substitutes for plastics in certain applications, but are usually limited by its high hydrophilicity, and low mechanical performance. To address this issue, polylactic acid (PLA) is blended with cellulose and chitosan to create a waterproof film that can be applied to starch-fiber foaming biodegradable composites to enhance their water resistance properties. Here, plant fibers as a reinforcement is incorporated to the modified starch by foaming mold at 260 °C, and PLA based hydrophobic film is coated onto the surface to prepare the novel hydrophobic bio-composites. The developed bio-composite exhibits comprehensive water barrier properties, which is significantly better than that of traditional starch and cellulose based materials. Introducing PLA films decreases water vapor permeability from 766.83 g/m2·24h to 664.89 g/m2·24h, and reduce hysteresis angles from 15.57° to 8.59° within the first five minutes after exposure to moisture. The water absorption rate of PLA films also decreases significantly from 12.3 % to 7.9 %. Additionally, incorporating hydrophobic films not only enhances overall waterproof performance but also improves mechanical properties of the bio-composites. The fabricated bio-composite demonstrates improved tensile strength from 2.09 MPa to 3.53 MPa.


Subject(s)
Hydrophobic and Hydrophilic Interactions , Polyesters , Starch , Tensile Strength , Water , Polyesters/chemistry , Starch/chemistry , Water/chemistry , Permeability , Chitosan/chemistry , Cellulose/chemistry , Steam , Surface Properties
12.
Int J Biol Macromol ; 267(Pt 1): 131374, 2024 May.
Article in English | MEDLINE | ID: mdl-38582474

ABSTRACT

Frequent change of wound dressings introduces wound inflammation and infections. In this study, we electrospun phenytoin (PHT) loaded ethyl cellulose (EC) microfibers and solvent cast tetracycline hydrochloride (TCH) loaded carboxymethyl cellulose (CMC) films with the aim to demonstrate tailorable in vitro drug release behaviors suitable for long-term use of wound dressings. Results from tensile testing showed a significant decrease in average elastic moduli from 8.8 ± 0.6 to 3.3 ± 0.3 MPa after incorporating PHT into EC fibers. PHT-loaded EC fibers displayed a slow and zero-ordered release up to 80 % of the total drug at 48 h, while TCH-loaded CMC films demonstrated a rapid and complete release within 30 min. Furthermore, drug-loaded EC/CMC composites were fabricated into fiber-in-film and fiber-on-film composites. Fiber-in-film composites showed stage release of TCH and PHT at 8 h, while fiber-on-film composites demonstrated simultaneous release of PHT and TCH with a prolonged release of TCH from CMC films. In general, electrospun PHT-loaded EC microfibers, solvent cast TCH-loaded CMC films, and their composites were studied to provide a fundamental scientific understanding on the novelty of the ability to modulate drug release characteristics based on the composite designs.


Subject(s)
Carboxymethylcellulose Sodium , Cellulose , Cellulose/analogs & derivatives , Drug Liberation , Cellulose/chemistry , Carboxymethylcellulose Sodium/chemistry , Solvents/chemistry , Phenytoin/chemistry , Tetracycline/chemistry , Tensile Strength
13.
Int J Biol Macromol ; 267(Pt 1): 131397, 2024 May.
Article in English | MEDLINE | ID: mdl-38582479

ABSTRACT

This study aimed to develop a multifunctional active composite film to extend the shelf life of minced pork. The composite film was prepared by incorporating zinc-doped grapefruit peel-derived carbon quantum dots (Zn-GFP-CD) into a cellulose nanofiber (CNF) matrix. The resulting film significantly improved UV-blocking properties from 39.0 % to 85.7 % while maintaining the film transparency. Additionally, the CNF/Zn-GFP-CD5% composite film exhibits strong antioxidant activity with ABTS and DPPH radical scavenging activities of 99.8 % and 77.4 %, respectively. The composite film also showed excellent antibacterial activity against both Gram-negative and Gram-positive bacteria. When used in minced pork packaging, the composite films effectively inhibit bacterial growth, maintaining bacterial levels below 7 Log CFU/g after 15 days and sustaining a red color over a 21-day storage period. Additionally, a significant reduction in the lipid oxidation of the minced pork was observed. These CNF/Zn-GFP-CD composite films have a great potential for active food packaging applications to extend shelf life and maintain the visual quality of packaged meat.


Subject(s)
Carbon , Cellulose , Citrus paradisi , Food Packaging , Nanofibers , Quantum Dots , Zinc , Quantum Dots/chemistry , Nanofibers/chemistry , Cellulose/chemistry , Food Packaging/methods , Zinc/chemistry , Citrus paradisi/chemistry , Carbon/chemistry , Antioxidants/chemistry , Antioxidants/pharmacology , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Animals , Swine
14.
Int J Biol Macromol ; 267(Pt 1): 131291, 2024 May.
Article in English | MEDLINE | ID: mdl-38583839

ABSTRACT

Bacterial cellulose (BC) hydrogels are promising medical biomaterials that have been widely used for tissue repair, wound healing and cartilage engineering. However, the high water content of BC hydrogels increases the difficulty of storage and transportation. Moreover, they will lose their original hydrogel structure after dehydration, which severely limits their practical applications. Introducing the bio-based polyelectrolytes is expected to solve this problem. Here, we modified BC and combined it with quaternized chitosan (QCS) via a chemical reaction to obtain a dehydrated dialdehyde bacterial cellulose/quaternized chitosan (DBC/QCS) hydrogel with repeated swelling behavior and good antibacterial properties. The hydrogel can recover the initial state on the macro scale with a swelling ratio over 1000 % and possesses excellent antimicrobial properties against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) with a killing rate of 80.8 % and 81.3 %, respectively. In addition, the hydrogel has excellent biocompatibility, which is conducive to the stretching of L929 cells. After 14 d of in vivo wound modeling in rats, it was found that the hydrogel loaded with pirfenidone (PFD) could promote collagen deposition and accelerate wound healing with scar prevention. This rehydratable hydrogel can be stored and transported under dry conditions, which is promising for practical applications.


Subject(s)
Anti-Bacterial Agents , Cellulose , Escherichia coli , Hydrogels , Staphylococcus aureus , Wound Healing , Wound Healing/drug effects , Animals , Anti-Bacterial Agents/pharmacology , Anti-Bacterial Agents/chemistry , Hydrogels/chemistry , Hydrogels/pharmacology , Rats , Staphylococcus aureus/drug effects , Cellulose/chemistry , Cellulose/pharmacology , Cellulose/analogs & derivatives , Escherichia coli/drug effects , Chitosan/chemistry , Chitosan/pharmacology , Mice , Cell Line , Male , Biocompatible Materials/chemistry , Biocompatible Materials/pharmacology
15.
Int J Biol Macromol ; 267(Pt 1): 131432, 2024 May.
Article in English | MEDLINE | ID: mdl-38583849

ABSTRACT

The potential applications of cellulose nanofibril-based foam materials can be expanded by their enhanced water durability. This study proposes two crosslinking methods to improve the water durability of the oven-dried carboxymethylated cellulose nanofibril (CMCNF) foam. The first method involves the addition of a crosslinker, polyamideamine epichlorohydrin. The second method is the self-crosslinking of CMCNFs via heat treatment at 140 °C for less than an hour, which is a simple way to crosslink CMCNF-based materials. Both crosslinking methods resulted in excellent water durability and wet resilience of the foams, which also exhibited high water absorbency. Furthermore, neither method affected the structural nor mechanical properties of the oven-dried CMCNF foams. In particular, self-crosslinking by heat treatment proved to be as effective as using a crosslinking agent. Compared to the freeze-dried foam, the oven-dried foam exhibited slower methylene blue (MB) dye adsorption but a higher maximum adsorption capacity (238-250 mg/g), attributed to the closed pore structure and a larger specific surface area. In addition, the isotherm and reusability of the foam for MB adsorption were investigated. These crosslinking processes expanded the potential use of oven-dried CMCNF foams as adsorbents for cationic dyes.


Subject(s)
Cellulose , Coloring Agents , Cross-Linking Reagents , Methylene Blue , Nanofibers , Water , Nanofibers/chemistry , Adsorption , Water/chemistry , Cellulose/chemistry , Cellulose/analogs & derivatives , Coloring Agents/chemistry , Methylene Blue/chemistry , Cross-Linking Reagents/chemistry , Water Pollutants, Chemical/chemistry , Water Purification/methods , Epichlorohydrin/chemistry
16.
Int J Biol Macromol ; 267(Pt 1): 131445, 2024 May.
Article in English | MEDLINE | ID: mdl-38588839

ABSTRACT

Carbonized bacterial cellulose embedded with highly dispersed nano zero-valent iron (nZVI), denoted as nZVI@CBC, was prepared through one-step in situ carbothermal treatment of bacterial cellulose adsorbing iron(III) nitrate. The structure characteristics of nZVI@CBC and its performance in removing hexavalent chromium Cr(VI) were investigated. Results showed the formation of nZVI@CBC with a surface area of 409.61 m2/g at 800 °C, with nZVI particles of mean size 28.2 nm well distributed within the fibrous network of CBC. The stability of nZVI was enhanced by its carbon coating, despite some inevitable oxidation of exposed nZVI. Batch experiments demonstrated that nZVI@CBC exhibited superior removal efficiency compared to bare nZVI and CBC. Under optimal conditions, nZVI@CBC exhibited a high Cr(VI) adsorption capacity of up to 372.42 mg/g. Therefore, nZVI@CBC shows promise as an effective adsorbent for remediating Cr(VI) pollution in water.


Subject(s)
Cellulose , Chromium , Iron , Water Pollutants, Chemical , Water Purification , Chromium/chemistry , Chromium/isolation & purification , Cellulose/chemistry , Adsorption , Iron/chemistry , Water Pollutants, Chemical/chemistry , Water Pollutants, Chemical/isolation & purification , Water Purification/methods , Carbon/chemistry , Bacteria
17.
Int J Biol Macromol ; 267(Pt 1): 131444, 2024 May.
Article in English | MEDLINE | ID: mdl-38588840

ABSTRACT

Ramie bone (RB), an agricultural waste generated in the textile industry, is a vastly productive renewable natural resource with the potential to be used as a source of cellulose. In this study, ramie bone cellulose (RB-CE) was obtained in one step using a simple and ecologically friendly hydrogen peroxide-citric acid (HPCA) treatment procedure that avoided the use of halogenated reagents and strong acids while also streamlining the treatment processes. Various analytical methods were used to investigate the chemical composition and structure, crystallinity, morphology, thermal properties, surface area and hydration properties of cellulose separated at different treatment temperatures. HPCA successfully removed lignin and hemicellulose from RB, according to chemical composition analysis and FTIR. RB-CE had a type I cellulose crystal structure, and the crystallinity improved with increasing treatment temperature, reaching 72.51 % for RB-CE90. The RB-CE showed good thermal stability with degradation temperatures ranging from 294.2 °C to 319.1 °C. Furthermore, RB-CE had a high water/oil binding capacity, with RB-CE90 having WHC and OBC of 9.68 g/g and 7.24 g/g, respectively. The current work serves as a model for the environmentally friendly and convenient extraction of cellulose from biomass, and the cellulose obtained can be employed in the field of food and composite materials.


Subject(s)
Cellulose , Hydrogen Peroxide , Cellulose/chemistry , Hydrogen Peroxide/chemistry , Bone and Bones/chemistry , Green Chemistry Technology/methods , Animals , Temperature , Lignin/chemistry , Lignin/isolation & purification , Water/chemistry
18.
Int J Biol Macromol ; 267(Pt 1): 131447, 2024 May.
Article in English | MEDLINE | ID: mdl-38588843

ABSTRACT

The drug encapsulation efficiency, release rate and time, sustained release, and stimulus-response of carriers are very important for drug delivery. However, these always cannot obtained for the carrier with a single component. To improve the comprehensive performance of chitosan-based carriers for 5-Fu delivery, diatomite-incorporated hydroxypropyl cellulose/chitosan (DE/HPC/CS) composite aerogel microspheres were fabricated for the release of 5-fluorouracil (5-Fu), and the release performance was regulated with the content of diatomite, pH value, and external coating material. Firstly, the 5-Fu loaded DE/HPC/CS composite aerogel microspheres and Eudragit L100 coated microspheres were prepared with cross-linking followed by freeze-drying, and characterized by SEM, EDS, FTIR, XRD, DSC, TG, and swelling. The obtained aerogel microspheres have a diameter of about 0.5 mm, the weight percentage of F and Si elements on the surface are 0.55 % and 0.78 % respectively. The glass transition temperature increased from 179 °C to 181 °C and 185 °C with the incorporation of DE and coating of Eudragit, and the equilibrium swelling percentage of DE/HPC/CS (1.5:3:2) carriers are 101.52 %, 45.27 %, 67.32 % at pH 1.2, 5.0, 7.4, respectively. Then, the effect of DE content on the drug loading efficiency of DE/HPC/CS@5-Fu was investigated, with the increase of DE content, the highest encapsulation efficiency was 82.6 %. Finally, the release behavior of DE incorporated and Eudragit L100 Coated microspheres were investigated under different pH values, and evaluated with four kinetic models. The results revealed that the release rate of 5-Fu decreased with the increase of DE content, sustained release with extending time and pH-responsive were observed for the Eudragit-coated aerogel microspheres.


Subject(s)
Cellulose , Cellulose/analogs & derivatives , Chitosan , Delayed-Action Preparations , Diatomaceous Earth , Drug Carriers , Drug Liberation , Fluorouracil , Microspheres , Polymethacrylic Acids , Chitosan/chemistry , Cellulose/chemistry , Fluorouracil/chemistry , Fluorouracil/administration & dosage , Diatomaceous Earth/chemistry , Polymethacrylic Acids/chemistry , Drug Carriers/chemistry , Hydrogen-Ion Concentration , Gels/chemistry
19.
Int J Biol Macromol ; 267(Pt 1): 131450, 2024 May.
Article in English | MEDLINE | ID: mdl-38588838

ABSTRACT

With the increasing severity of energy shortages and environmental pollution, there is an urgent need for advanced thermal insulation materials with excellent comprehensive performance, including low thermal conductivity, high flame resistance, and strong compressive strength. Herein, an anisotropic composite aerogel based on cellulose nanofibers (CNF), calcium alginate (CA), and boric acid (BA) is fabricated using a directional freeze-drying strategy. The CA and BA, as double cross-linking agents, associated with oriented porous structure provide the resultant aerogel with good mechanical strength. Additionally, self-flame retardant CA and BA act as synergistic flame retardants that endow the aerogel with excellent flame retardance properties such as a limiting oxygen index value of 44.2 %, UL-94 V-0 rating, and low heat release. Furthermore, this composite aerogel exhibits outstanding thermal insulation performance with a low thermal conductivity of approximately 30 mW m-1 K-1. Therefore, the composite aerogel is expected to have a wide potential application in areas such as construction, automotive industry, batteries, petrochemical pipelines, and high-temperature reaction devices.


Subject(s)
Alginates , Boric Acids , Cellulose , Flame Retardants , Gels , Nanofibers , Thermal Conductivity , Nanofibers/chemistry , Boric Acids/chemistry , Cellulose/chemistry , Alginates/chemistry , Gels/chemistry , Anisotropy , Porosity
20.
Int J Biol Macromol ; 267(Pt 1): 131448, 2024 May.
Article in English | MEDLINE | ID: mdl-38593901

ABSTRACT

Nowadays, various harmful indoor pollutants especially including bacteria and residual formaldehyde (HCHO) seriously threaten human health and reduce the quality of public life. Herein, a universal substrate-independence finishing approach for efficiently solving these hybrid indoor threats is demonstrated, in which amine-quinone network (AQN) was employed as reduction agent to guide in-situ growth of Ag@MnO2 particles, and also acted as an adhesion interlayer to firmly anchor nanoparticles onto diverse textiles, especially for cotton fabrics. In contrast with traditional hydrothermal or calcine methods, the highly reactive AQN ensures the efficient generation of functional nanoparticles under mild conditions without any additional catalysts. During the AQN-guided reduction, the doping of Ag atoms onto cellulose fiber surface optimized the crystallinity and oxygen vacancy of MnO2, providing cotton efficient antibacterial efficiency over 90 % after 30 min of contact, companying with encouraging UV-shielding and indoor HCHO purification properties. Besides, even after 30 cycles of standard washing, the Ag@MnO2-decorated textiles can effectively degrade HCHO while well-maintaining their inherent properties. In summary, the presented AQN-mediated strategy of efficiently guiding the deposition of functional particles on fibers has broad application prospects in the green and sustainable functionalization of textiles.


Subject(s)
Amines , Cellulose , Manganese Compounds , Oxides , Manganese Compounds/chemistry , Oxides/chemistry , Cellulose/chemistry , Amines/chemistry , Quinones/chemistry , Silver/chemistry , Formaldehyde/chemistry , Anti-Bacterial Agents/chemistry , Anti-Bacterial Agents/pharmacology , Textiles , Air Pollution, Indoor/prevention & control
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