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1.
Mol Biol Rep ; 51(1): 658, 2024 May 15.
Artigo em Inglês | MEDLINE | ID: mdl-38748314

RESUMO

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.


Assuntos
Celulose , Mucosa Intestinal , Intestino Delgado , Nanopartículas Metálicas , Nanofibras , Ratos Wistar , Prata , Alicerces Teciduais , Cicatrização , Animais , Prata/química , Celulose/análogos & derivados , Celulose/química , Cicatrização/efeitos dos fármacos , Nanopartículas Metálicas/química , Ratos , Nanofibras/química , Alicerces Teciduais/química , Mucosa Intestinal/metabolismo , Masculino , Intestino Delgado/metabolismo , Bovinos , Fator de Crescimento Transformador beta/metabolismo , Engenharia Tecidual/métodos , Colágeno
2.
Molecules ; 29(9)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38731558

RESUMO

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.


Assuntos
Celulose , Escherichia coli , Nanopartículas Metálicas , Prata , Staphylococcus aureus , Prata/química , Nanopartículas Metálicas/química , Escherichia coli/efeitos dos fármacos , Staphylococcus aureus/efeitos dos fármacos , Celulose/química , Celulose/análogos & derivados , Antibacterianos/farmacologia , Antibacterianos/química , Nanofibras/química , Nanocompostos/química , Testes de Sensibilidade Microbiana , Anti-Infecciosos/química , Anti-Infecciosos/farmacologia , Espectroscopia de Infravermelho com Transformada de Fourier
3.
Carbohydr Polym ; 337: 122112, 2024 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-38710545

RESUMO

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.


Assuntos
Celulose , Embalagem de Alimentos , Lignina , Lignina/análogos & derivados , Nanocompostos , Nanofibras , Resistência à Tração , Madeira , Xilanos , Embalagem de Alimentos/métodos , Lignina/química , Nanocompostos/química , Celulose/química , Celulose/análogos & derivados , Madeira/química , Nanofibras/química , Xilanos/química , Antioxidantes/química , Frutas/química
4.
J Colloid Interface Sci ; 667: 624-639, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38663278

RESUMO

Quick scarless healing remains a key issue for diabetic wounds. Here, a stretchable elastomeric hydrogel dressing composed of hydroxyethylcellulose (HEC), silk nano fiber-magnesium ion complex (Mg2+-SNF) and glycerol (Gly) was developed to optimize mechanical niche, anti-inflammatory and angiogenic behavior simultaneously. The composite hydrogel dressing exhibited skin-like elasticity (175.1 ± 23.9 %) and modulus (156.7 ± 2.5 KPa) while Mg2+-SNF complex endowed the dressing with angiogenesis, both favoring quick scarless skin regeneration. In vitro cell studies revealed that the hydrogel dressing stimulated fibroblast proliferation, endothelial cell migration and vessel-like tube formation, and also induced anti-inflammatory behavior of macrophages. In vivo results revealed accelerated healing of diabetic wounds. The improved granulation ingrowth and collagen deposition suggested high quality repair. Both thinner epidermal layer and low collagen I/III ratio of the regenerated skin confirmed scarless tissue formation. This bioactive hydrogel dressing has promising potential to address the multifaceted challenges of diabetic wound management.


Assuntos
Glicerol , Magnésio , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Glicerol/química , Glicerol/farmacologia , Magnésio/química , Magnésio/farmacologia , Camundongos , Seda/química , Hidrogéis/química , Hidrogéis/farmacologia , Materiais Biomiméticos/química , Materiais Biomiméticos/farmacologia , Diabetes Mellitus Experimental/tratamento farmacológico , Bandagens , Humanos , Ratos , Nanofibras/química , Proliferação de Células/efeitos dos fármacos , Neovascularização Fisiológica/efeitos dos fármacos , Masculino , Células Endoteliais da Veia Umbilical Humana , Celulose/química , Celulose/farmacologia , Celulose/análogos & derivados
5.
Int J Biol Macromol ; 268(Pt 1): 131622, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38636762

RESUMO

Separator is an essential component of lithium-ion batteries (LIBs), which is placed between the electrodes to impede their electrical contact and provide the transport channels for lithium ions. Traditionally, the separator contributes the overall mass of LIBs, thereby reducing the gravimetric capacity of the devices. Herein, a dual-layer redox-active cellulose separator is designed and fabricated to enhance the electrochemical performances of LIBs by introducing NiS. The presented separator is composed of an insulating bacterial cellulose (BC) nanofiber layer and a conductive, and redox-active NiS@BC/carbon nanotubes layer. By using the NiS@BC separator, the discharge capacity of the LiFePO4//Li half battery is enhanced to 117 mAh g-1 at a current of 2C owing to the redox-activity of NiS. Moreover, the functional separator-electrode interface can facilitate the homogenous Li stripping/plating and depress the polarization upon the repeated stripping/plating process. Consequently, the battery containing the redox-active separator exhibits outstanding cycle stability and rate capability. The present study contributes a novel strategy for the developments of functional separators to improve the electrochemical properties of LIBs.


Assuntos
Celulose , Fontes de Energia Elétrica , Eletrodos , Lítio , Nanofibras , Oxirredução , Lítio/química , Nanofibras/química , Celulose/química , Celulose/análogos & derivados , Nanotubos de Carbono/química , Íons/química , Técnicas Eletroquímicas
6.
Int J Biol Macromol ; 268(Pt 1): 131672, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38643912

RESUMO

The packaging industry has primarily been dominated by single-use, petrochemical-sourced plastic materials despite their short-term use. Their leakage into the ecosystem after their use poses substantial environmental concerns. As a result, compostable and renewable packaging material alternatives are garnering significant attention. Cellulose acetate is a derivative of cellulose that exhibits excellent tensile properties, transparency, melt processability, and intermediate compostability. However, its application in the food packaging industry is limited due to its hygroscopic behavior and lack of dimensional stability. This study investigated using lignin (pristine and esterified) as a functional additive of cellulose acetate. The effect of varying concentrations of pristine kraft and oleic acid functionalized lignin in the cellulose acetate matrix and its effect on the resulting film's mechanical, morphological, viscoelastic, and water barrier properties were explored. Comprehensive characterization of the thermomechanical processed lignin-cellulose acetate sheets revealed reduced moisture absorption, improved UV and moisture barrier, and enhanced tensile properties with melt processability. Overall, the studied films could have appealing properties for food and other packaging applications, thus, serving as eco-friendly and sustainable alternatives to conventional petroleum-derived packing materials.


Assuntos
Celulose , Interações Hidrofóbicas e Hidrofílicas , Lignina , Ácido Oleico , Resistência à Tração , Lignina/química , Lignina/análogos & derivados , Celulose/química , Celulose/análogos & derivados , Ácido Oleico/química , Embalagem de Alimentos/métodos , Água/química
7.
Int J Biol Macromol ; 268(Pt 1): 131727, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649073

RESUMO

Biodegradable edible films for sour cream packaging were developed based on chitosan (CS), hydroxyethyl cellulose (HEC), Olive leaf extract (OE), and titanium dioxide nanoparticles (TiO2-NPs). The prepared CS/HEC/TiO2-OE bionanocomposite films were evaluated for their antimicrobial and antioxidant activities as well as using FT-IR, mechanical, permeability, and contact angle. The effect of developed films on the lipid oxidation, microbiological load, and chemical properties of sour cream was investigated. The fabricated films had an antimicrobial impact against all tested strains. The film containing 8 % OE showed effective protection against fat oxidation, with a peroxide value of 3.21 meq O2/kg, a para-anisidine value 5.40, and free fatty acids of 0.82 mg KOH/kg. The films with OE 4 % and 8 % have a good effect on the microbiological load of sour cream for 90 days. These films did not influence the chemical composition of sour cream and therefore can be used in this sort of dairy product.


Assuntos
Celulose , Quitosana , Filmes Comestíveis , Embalagem de Alimentos , Olea , Extratos Vegetais , Folhas de Planta , Titânio , Quitosana/química , Quitosana/farmacologia , Titânio/química , Celulose/química , Celulose/análogos & derivados , Folhas de Planta/química , Extratos Vegetais/química , Extratos Vegetais/farmacologia , Olea/química , Embalagem de Alimentos/métodos , Antioxidantes/farmacologia , Antioxidantes/química , Permeabilidade , Anti-Infecciosos/farmacologia , Anti-Infecciosos/química , Espectroscopia de Infravermelho com Transformada de Fourier , Nanopartículas/química
8.
Int J Biol Macromol ; 268(Pt 1): 131652, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38649075

RESUMO

Vinylsulfonic acid (VSA), acrylamide (AM) and N, N methylene bis acrylamide(MBA) were copolymerized by radical polymerization in the presence of gum ghatti (GG) and treated water hyacianth (WH) in water. Several composite copolymers were prepared by varying the i) AM: VSA molar ratios ii) wt% of GG and iii) wt% of treated WH based on a Box-Behnken Design(BBD) of a response surface methodology (RSM) model with three input variables and the batch adsorption capacity (mg/g) of 100 mg/L Cd (II) from water as response. The composite polymer was characterized by Fourier transform Infrared spectroscopy (FTIR), X-ray diffraction (XRD), thermogravimetric analysis(TGA), X- ray photo electron spectroscopy (XPS), compressive strength, pH reversibility, pH at point zero charge (pHPZC), Brunauer-Emmett-Teller (BET) surface area and scanning electron microscopy (SEM). The network parameters of the composites were determined. The copolymer composite prepared with AM: VSA of 5:1 containing 10 wt% GG and 4 wt% treated WH showed an optimum batch adsorption capacity of 399.15 mg/g Cd (II) from water containing 100 mg/L Cd (II). The same composite showed an adsorption capacity of 170.1 mg/g and a removal% of 31.5 at a feed concentration/feed flow rate/bed height of 150 mgL-1/30mLmin-1/30 mm in a fixed bed column.


Assuntos
Celulose , Gomas Vegetais , Adsorção , Gomas Vegetais/química , Celulose/química , Celulose/análogos & derivados , Ácidos Sulfônicos/química , Purificação da Água/métodos , Água/química , Concentração de Íons de Hidrogênio , Acrilamida/química , Poluentes Químicos da Água/química , Poluentes Químicos da Água/isolamento & purificação , Polimerização , Difração de Raios X , Acrilamidas/química , Resinas Acrílicas/química , Espectroscopia de Infravermelho com Transformada de Fourier , Cádmio/química , Polivinil/química
9.
Chemosphere ; 358: 142164, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38685326

RESUMO

As the adverse effects of using plastics and perfluorinated alkyl substances become more apparent, there is a growing need for sustainable hydrophobic products. Cellulose and its derivatives are the most abundant and widely used polymers, and cellulose-based products have great potential in industries where plastics and other hydrophobic polymers are used, such as stain-resistant fabrics, food packaging, and oil-water separation applications. In this study, we extracted cellulose from water hyacinth (WH) biomass, known for its negative environmental impact, and converted it into hydrophobic cellulose. This addresses the issue of managing WH waste and creating an environmentally friendly hydrophobic material. Initially, aldehyde groups were introduced through oxidation with periodate, followed by direct octadecyl amine (ODA) grafting onto dialdehyde cellulose (DAC) via a Schiff base condensation. The resulting ODA modified cellulose (ODA-C) was dispersed in ethanol and used to coat various materials, including cotton fabric, cellulose filter paper, and packaging paper. The modified materials showed excellent hydrophobicity as measured by their water contact angles (WCAs), and the application of the coating was demonstrated for oil-water separation, stain-resistant hydrophobic fabric, and paper-based packaging materials. FTIR, XRD, and WCA analysis confirmed the successful modification of cellulose. A high separation efficiency of 99% was achieved for diesel/water separation using modified filter paper (MoFP), under gravity. On application of the coating, cotton fabric became hydrophobic and resisted staining from dye, and paper-based packaging materials became more robust by becoming water-resistant. Overall, the facile synthesis, low cost, high efficiency, and use of environmentally friendly sustainable materials make this a promising strategy for hydrophobically modifying surfaces for a wide range of applications while reducing the menace of water hyacinth.


Assuntos
Biomassa , Celulose , Interações Hidrofóbicas e Hidrofílicas , Silanos , Celulose/química , Celulose/análogos & derivados , Silanos/química , Eichhornia/química , Água/química , Flúor/química , Óleos/química
11.
Int J Biol Macromol ; 266(Pt 1): 131209, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38565364

RESUMO

Mercury ion (Hg2+) is one of harmful heavy metal ions that can accumulate inside the human organism and cause some health problems. In the article, a highly effective fluorescent probe named EC-T-PCBM was prepared by grafting flavonol derivatives onto ethyl cellulose for the specific recognition of Hg2+. EC-T-PCBM exhibited a remarkable fluorescence light-up response toward Hg2+ with excellent sensitivity. EC-T-PCBM possessed several prominent sensing properties for Hg2+, such as low detection limit (43.9 nM), short response time (5 min), and wide detection pH range (6-9). The response mechanism of EC-T-PCBM to Hg2+ has been verified through 1H NMR titration and DFT computation. Additionally, EC-T-PCBM not only can be used for accurately determining trace amount of Hg2+ in actual environmental water samples, but also can serve as a portable and rapid device by loading it on test strips for sensitive and selective visualization of Hg2+. More importantly, the confocal fluorescence imaging of onion cells suggested the favorable cell membrane permeability of EC-T-PCBM and its prominent ability to continuously monitor the enrichment from Hg2+ within fresh plant tissues.


Assuntos
Celulose , Flavonóis , Corantes Fluorescentes , Mercúrio , Mercúrio/análise , Celulose/química , Celulose/análogos & derivados , Corantes Fluorescentes/química , Flavonóis/química , Flavonóis/análise , Espectrometria de Fluorescência/métodos , Limite de Detecção , Concentração de Íons de Hidrogênio , Poluentes Químicos da Água/análise , Cebolas/química , Imagem Óptica/métodos
12.
Environ Sci Pollut Res Int ; 31(20): 29992-30008, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38598154

RESUMO

The need to effectively remove toxic organic dyes from aquatic systems has become an increasingly critical issue in the recent years. In pursuit of this objective, polydopamine (PDA)-binary ZIF-8/UiO-66 (MOFs) was synthesized and incorporated into cellulose acetate (CA), producing ZIF-8/UiO-66/PDA@CA composite nanofibers under meticulously optimized conditions. The potential of fabricated nanofibers to remove cationic methylene blue (MB) dye was investigated. Various analysis tools including FTIR, XRD, SEM, zeta potential, BET, tensile strength testing, and XPS were employed. Results revealed a substantial leap in tensile strength, with ZIF-8/UiO-66/PDA@CA registering an impressive 2.8 MPa, as a marked improvement over the neat CA nanofibers (1.1 MPa). ZIF-8/UiO-66/PDA@CA nanofibers exhibit an outstanding adsorption capacity of 82 mg/g, notably outperforming the 22.4 mg/g capacity of neat CA nanofibers. In binary dye systems, these nanofibers exhibit a striking maximum adsorption capacity of 108 mg/g, establishing their eminence in addressing the complexities of wastewater treatment. Furthermore, the adsorption data fitted to the Langmuir isotherm, and the pseudo-second-order kinetic model. The fabricated nanofiber demonstrates good reproducibility and durability, consistently upholding its performance over five cycles. This suite of remarkable attributes collectively underscores its potential as a robust, durable, and highly promising solution for the effective and efficient removal of pernicious MB dye, in the context of both water quality improvement and environmental preservation.


Assuntos
Celulose , Celulose/análogos & derivados , Corantes , Indóis , Nanofibras , Polímeros , Poluentes Químicos da Água , Nanofibras/química , Celulose/química , Indóis/química , Polímeros/química , Corantes/química , Poluentes Químicos da Água/química , Adsorção
13.
Int J Biol Macromol ; 267(Pt 2): 131543, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38614169

RESUMO

A temperature/pH dual sensitive hydrogel with a semi-interpenetrating network (semi-IPN) structure was synthesized through an aqueous amino-succinimide reaction between water-soluble polysuccinimide and polyethyleneimine in the presence of thermosensitive cellulose derivatives. Single-factor experiments were carried out to optimize the preparation conditions of the semi-IPN hydrogel. The swelling behavior and cytotoxicity assay of the hydrogel were tested. Finally, taking 5- fluorouracil (5-Fu) as a model drug, the release performance of the 5-Fu-loaded hydrogel was investigated. The results indicated that the swelling ratio (SR) first decreased and then increased when the pH of the solutions ascended from 2 to 10. The SR decreased with the increase in temperature. In addition, the swelling behavior of the hydrogel was reversible and reproducible under different pH values and temperatures. The prepared hydrogels had good cytocompatibility. The release behavior of 5-Fu was most consistent with the Korsmeyer-Peppas model and followed the case II diffusion. The acidic environment was beneficial for the release of 5-Fu. The preparation process of the semi-IPN hydrogel is simple and the reaction can proceed quickly in water. The strategy introduced here has great potential for application in the preparation of drug carriers.


Assuntos
Celulose , Fluoruracila , Hidrogéis , Succinimidas , Temperatura , Hidrogéis/química , Hidrogéis/síntese química , Celulose/química , Celulose/análogos & derivados , Concentração de Íons de Hidrogênio , Fluoruracila/química , Fluoruracila/farmacologia , Succinimidas/química , Água/química , Liberação Controlada de Fármacos , Portadores de Fármacos/química , Humanos
14.
Int J Biol Macromol ; 267(Pt 1): 131374, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38582474

RESUMO

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.


Assuntos
Carboximetilcelulose Sódica , Celulose , Celulose/análogos & derivados , Liberação Controlada de Fármacos , Celulose/química , Carboximetilcelulose Sódica/química , Solventes/química , Fenitoína/química , Tetraciclina/química , Resistência à Tração
15.
Int J Biol Macromol ; 267(Pt 1): 131291, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583839

RESUMO

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.


Assuntos
Antibacterianos , Celulose , Escherichia coli , Hidrogéis , Staphylococcus aureus , Cicatrização , Cicatrização/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Antibacterianos/química , Hidrogéis/química , Hidrogéis/farmacologia , Ratos , Staphylococcus aureus/efeitos dos fármacos , Celulose/química , Celulose/farmacologia , Celulose/análogos & derivados , Escherichia coli/efeitos dos fármacos , Quitosana/química , Quitosana/farmacologia , Camundongos , Linhagem Celular , Masculino , Materiais Biocompatíveis/química , Materiais Biocompatíveis/farmacologia
16.
Int J Biol Macromol ; 267(Pt 1): 131432, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38583849

RESUMO

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.


Assuntos
Celulose , Corantes , Reagentes de Ligações Cruzadas , Azul de Metileno , Nanofibras , Água , Nanofibras/química , Adsorção , Água/química , Celulose/química , Celulose/análogos & derivados , Corantes/química , Azul de Metileno/química , Reagentes de Ligações Cruzadas/química , Poluentes Químicos da Água/química , Purificação da Água/métodos , Epicloroidrina/química
17.
Int J Biol Macromol ; 267(Pt 1): 131447, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38588843

RESUMO

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.


Assuntos
Celulose , Celulose/análogos & derivados , Quitosana , Preparações de Ação Retardada , Terra de Diatomáceas , Portadores de Fármacos , Liberação Controlada de Fármacos , Fluoruracila , Microesferas , Ácidos Polimetacrílicos , Quitosana/química , Celulose/química , Fluoruracila/química , Fluoruracila/administração & dosagem , Terra de Diatomáceas/química , Ácidos Polimetacrílicos/química , Portadores de Fármacos/química , Concentração de Íons de Hidrogênio , Géis/química
18.
Biomed Phys Eng Express ; 10(4)2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38640908

RESUMO

Extracellular vesicles (EVs) have been recognized as one of the promising specific drugs for myocardial infarction (MI) prognosis. Nevertheless, low intramyocardial retention of EVs remains a major impediment to their clinical application. In this study, we developed a silk fibroin/hydroxypropyl cellulose (SF/HPC) composite hydrogel combined with AC16 cell-derived EVs targeted modification by folic acid for the treatment of acute myocardial infarction repair. EVs were functionalized by distearoylphosphatidyl ethanolamine-polyethylene glycol (DSPE-PEG-FA) via noncovalent interaction for targeting and accelerating myocardial infarction repair.In vitro, cytocompatibility analyses revealed that the as-prepared hydrogels had excellent cell viability by MTT assay and the functionalized EVs had higher cell migration by scratch assay.In vivo, the composite hydrogels can promote myocardial tissue repair effects by delaying the process of myocardial fibrosis and promoting angiogenesis of infarct area in MI rat model.


Assuntos
Celulose , Celulose/análogos & derivados , Vesículas Extracelulares , Fibroínas , Hidrogéis , Infarto do Miocárdio , Infarto do Miocárdio/tratamento farmacológico , Animais , Vesículas Extracelulares/metabolismo , Fibroínas/química , Ratos , Celulose/química , Hidrogéis/química , Ratos Sprague-Dawley , Sobrevivência Celular/efeitos dos fármacos , Masculino , Polietilenoglicóis/química , Movimento Celular/efeitos dos fármacos , Miocárdio/metabolismo , Miocárdio/patologia , Ácido Fólico/química , Humanos , Linhagem Celular
19.
Carbohydr Polym ; 336: 122105, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670749

RESUMO

In situ forming hydrogels are promising for biomedical applications, especially in drug delivery. The precursor solution can be injected at the target site, where it undergoes a sol-gel transition to afford a hydrogel. In this sense, the most significant characteristic of these hydrogels is fast gelation behavior after injection. This study describes an all-polysaccharide, rapidly in situ-forming hydrogel composed of carboxymethyl chitosan (CMCHT) and hydroxyethyl cellulose functionalized with aldehyde groups (HEC-Ald). The HEC-Ald was synthesized through acetal functionalization, followed by acid deprotection. This innovative approach avoids cleavage of pyran rings, as is inherent in the periodate oxidation approach, which is the most common method currently employed for adding aldehyde groups to polysaccharides. The resulting hydrogel exhibited fast stress relaxation, self-healing properties, and pH sensitivity, which allowed it to control the release of an encapsulated model drug in response to the medium pH. Based on the collected data, the HEC-Ald/CMCHT hydrogels show promise as pH-sensitive drug carriers.


Assuntos
Aldeídos , Celulose , Celulose/análogos & derivados , Quitosana , Quitosana/análogos & derivados , Hidrogéis , Quitosana/química , Concentração de Íons de Hidrogênio , Celulose/química , Hidrogéis/química , Aldeídos/química , Portadores de Fármacos/química , Liberação Controlada de Fármacos , Polissacarídeos/química
20.
Carbohydr Polym ; 336: 122133, 2024 Jul 15.
Artigo em Inglês | MEDLINE | ID: mdl-38670771

RESUMO

Using respiratory protective equipment is one of the relevant preventive measures for infectious diseases, including COVID-19, and for various occupational respiratory hazards. Because experienced discomfort may result in a decrease in the utilization of respirators, it is important to enhance the material properties to resolve suboptimal usage. We combined several technologies to produce a filtration material that met requirements set by a cross-disciplinary interview study on the usability of protective equipment. Improved breathability, environmental sustainability, and comfort of the material were achieved by electrospinning poly(ethylene oxide) (PEO) nanofibers on a thin foam-formed fabric from regenerated cellulose fibers. The high filtration efficiency of sub-micron-sized diethylhexyl sebacate (DEHS) aerosol particles resulted from the small mean segment length of 0.35 µm of the nanofiber network. For a particle diameter of 0.6 µm, the filtration efficiency of a single PEO layer varied in the range of 80-97 % depending on the coat weight. The corresponding pressure drop had the level of 20-90 Pa for the airflow velocity of 5.3 cm/s. Using a multilayer structure, a very high filtration efficiency of 99.5 % was obtained with only a slightly higher pressure drop. This opens a route toward designing sustainable personal protective media with improved user experience.


Assuntos
Celulose , Filtração , Nanofibras , Celulose/química , Celulose/análogos & derivados , Filtração/métodos , Nanofibras/química , Humanos , COVID-19/prevenção & controle , Polietilenoglicóis/química , Dispositivos de Proteção Respiratória , Tamanho da Partícula , SARS-CoV-2 , Aerossóis/química
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