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1.
Wounds ; 36(8): 263-273, 2024 08.
Artículo en Inglés | MEDLINE | ID: mdl-39241767

RESUMEN

BACKGROUND: A new indication for use of silver collagen oxidized regenerated cellulose (ORC) dressing in conjunction with negative pressure wound therapy (NPWT) and reticulated open cell foam (ROCF) dressings has recently become available. OBJECTIVE: An in-person meeting with 7 health care providers (HCPs) was held to identify clinical care settings and appropriate use of silver collagen ORC dressings in conjunction with NPWT and ROCF dressings. METHODS: Consensus statements were developed using a modified Delphi technique. An additional 25 HCPs completed an anonymous survey on the consensus statements. Consensus was defined as ≥80% agreement among survey respondents. RESULTS: Use of silver collagen ORC dressings with NPWT and ROCF dressings was recommended in inpatient and outpatient health care settings. Use in traumatic wounds, surgical wounds, diabetic ulcers, venous leg ulcers, and pressure injuries/ulcers was supported. Use was not recommended in the presence of exposed unprotected organs or exposed unprotected vessels, when the potential for inadequate wound hemostasis exists, acutely ischemic wounds, third-degree burns, or surgically closed incisions, or with patient hypersensitivity to product components. CONCLUSIONS: Limited evidence exists on use of NPWT in conjunction with silver collagen ORC dressings. A panel developed 12 consensus statements detailing the recommended and contraindicated uses of NPWT in conjunction with silver collagen ORC dressings.


Asunto(s)
Celulosa Oxidada , Colágeno , Consenso , Terapia de Presión Negativa para Heridas , Cicatrización de Heridas , Humanos , Terapia de Presión Negativa para Heridas/métodos , Celulosa Oxidada/uso terapéutico , Cicatrización de Heridas/efectos de los fármacos , Heridas y Lesiones/terapia , Vendajes , Úlcera por Presión/terapia , Técnica Delphi
2.
Int J Biol Macromol ; 277(Pt 4): 134464, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39098701

RESUMEN

In this study, lignin nanoparticles (LN) and octadecylamine-modified LN (LN-ODA) were utilized as coating materials to enhance the hydrophobic, antioxidant, and ultraviolet radiation-shielding (UV-shielding) properties of a TEMPO-oxidized nanocellulose film (TOCNF). The water contact angle (WCA) of the TOCNF was approximately 53° and remained stable for 1 min, while the modified LN-ODA-coated TOCNF reached over 130° and maintained approximately 85° for an hour. Pure TOCNF exhibited low antioxidant properties (4.7 %), which were significantly enhanced in TOCNF-LN (81.6 %) and modified LN-ODA (10.3 % to 27.5 %). Modified LN-ODA-coated TOCNF exhibited antioxidant properties two to six times higher than those of pure TOCNF. Modified LN-ODA exhibited thermal degradation max (Tmax) at 421 °C, while pure LN showed the main degradation temperature at approximately Tmax 330 °C. The thermal stability of TOCNF-LN-ODA-coated materials remained consistent with that of pure TOCNF, while the crystallinity index of the sample showed a slight decrease due to the amorphous nature of the lignin structure. The tensile strength of TOCNF was approximately 114.1 MPa and decreased to 80.1, 51.3, and 30.3 MPa for LN-ODA coating at 5, 10, and 15 g/m2, respectively.


Asunto(s)
Antioxidantes , Óxidos N-Cíclicos , Interacciones Hidrofóbicas e Hidrofílicas , Lignina , Nanofibras , Nanopartículas , Rayos Ultravioleta , Lignina/química , Antioxidantes/química , Óxidos N-Cíclicos/química , Nanopartículas/química , Nanofibras/química , Oxidación-Reducción , Celulosa Oxidada/química , Celulosa/química
3.
Spectrochim Acta A Mol Biomol Spectrosc ; 323: 124930, 2024 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-39111031

RESUMEN

Residual chlorine from widespread disinfection processes forms byproducts in water that are harmful to humans and ecosystems. Portable sensors are essential tools for the on-site monitoring of residual chlorine in environmental samples. Here, an inexpensive colorimetric sensor was developed by grafting via amidation the chromogen orthotolidine (OTO) to the surface of a TEMPO-oxidized cellulose filter paper (O-TOFP). A thorough characterization of the sensor strip demonstrated that it was highly stable and that it could be stored for a long period before usage. O-TOFP had a fast response time of 30 s, was highly selective for residual chlorine ions (ClO-) with an accuracy of at least 95 %, and exhibited an excellent limit of detection of only 0.045 mg/L when combined with smartphone image acquisition. With its many positive features, the easy-to-use and robust O-TOFP sensor described here could become a useful tool for the determination of residual chlorine in different water samples.


Asunto(s)
Celulosa Oxidada , Cloro , Colorimetría , Colorimetría/métodos , Cloro/análisis , Cloro/química , Celulosa Oxidada/análisis , Celulosa Oxidada/química , Límite de Detección , Contaminantes Químicos del Agua/análisis , Papel
4.
Colloids Surf B Biointerfaces ; 244: 114174, 2024 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-39197327

RESUMEN

Hemangiomas are superficial tumors characterized by dense vascular structures that often affect the patient's aesthetic appearance due to the obvious red appearance on the skin. Current treatments, especially timolol maleate in the form of eye drops and hydrogels, suffer from low transdermal drug delivery rates, resulting in prolonged treatment time. To address this challenge, our study introduced a soluble microneedle patch with dextran as the main material to form microcatheters for sustained delivery of timolol maleate. In addition, we proposed a vascular embolization strategy to disrupt the blood supply in hemangiomas. Oxidized cellulose (C-cellulose) was selected for its excellent hemostatic properties. We incorporated C-cellulose into dextran microneedles to facilitate thrombosis in the vascular-rich areas of hemangiomas. The innovative microneedle patch we developed can penetrate the skin to a depth of 430 µm and dissolve rapidly within 3 minutes, ensuring direct drug delivery to the subcutaneous layer. Notably, the treated skin area regained its original appearance within two hours after treatment. In addition to excellent skin permeability and rapid dissolution, these patches significantly promoted apoptosis and inhibited cell migration in mouse hemangioendothelioma EOMA cells. Our results demonstrate that this approach not only achieves significant tumor inhibition in a mouse hemangioma model, but also represents a more effective, convenient, and non-invasive treatment option. Therefore, dextran/C-cellulose/timolol maleate microneedle patch (MNs/Timolol) has broad clinical application prospects in the treatment of hemangiomas, minimizing the risk of additional damage and improving treatment efficacy.


Asunto(s)
Celulosa Oxidada , Sistemas de Liberación de Medicamentos , Hemangioma , Agujas , Timolol , Timolol/administración & dosificación , Timolol/farmacocinética , Timolol/farmacología , Animales , Hemangioma/tratamiento farmacológico , Hemangioma/patología , Ratones , Celulosa Oxidada/química , Celulosa Oxidada/farmacología , Celulosa Oxidada/administración & dosificación , Embolización Terapéutica/métodos , Administración Cutánea , Apoptosis/efectos de los fármacos , Parche Transdérmico
5.
Int J Biol Macromol ; 277(Pt 1): 134063, 2024 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-39038565

RESUMEN

More sustainable materials have been becoming an important concern of worldwide scientists, and cellulosic materials are one alternative in water decontamination. An efficient strategy to improve removal capacity is functionalizing or incorporating nanomaterials in cellulose-based materials. The new hybrid cDAC/ZnONPs was produced by green synthesis of zinc oxide nanoparticles (ZnONPs), promoting the in situ reduction and immobilization on the cationic dialdehyde cellulose microfibers (cDAC) surface to remove Congo red dye from water. cDAC/ZnONPs was characterized by scanning electron microscopy (SEM-EDS) and infrared spectroscopy (FTIR), which showed efficient nanoparticles reduction. Adsorption efficiency on cationic cellulose surface was investigated by pH, contact time, initial concentration, and dye selectivity tests. The material followed the H isotherm model, which resulted in a maximum adsorption capacity of 1091.16 mg/g. Herein, was developed an efficient and ecologically correct new adsorbent, highly effective in Congo red dye adsorption even at high concentrations, suitable for the remediation of contaminated industrial effluents.


Asunto(s)
Rojo Congo , Contaminantes Químicos del Agua , Purificación del Agua , Óxido de Zinc , Óxido de Zinc/química , Rojo Congo/química , Rojo Congo/aislamiento & purificación , Contaminantes Químicos del Agua/química , Contaminantes Químicos del Agua/aislamiento & purificación , Adsorción , Purificación del Agua/métodos , Tecnología Química Verde , Concentración de Iones de Hidrógeno , Celulosa/química , Celulosa/análogos & derivados , Colorantes/química , Nanopartículas/química , Cinética , Nanopartículas del Metal/química , Celulosa Oxidada/química , Cationes/química
6.
Carbohydr Polym ; 342: 122404, 2024 Oct 15.
Artículo en Inglés | MEDLINE | ID: mdl-39048239

RESUMEN

A new ultra-hydrophilic elastic sponge composite has been proposed. Medicinal herbs, commonly used in herbal medicine and subsequently discarded, are rich in natural polymer substances, making them promising candidates for various material industries. TEMPO-oxidized cellulose was extracted from medicinal herb residue, and the physicochemical properties of an ultra-hydrophilic elastic sponge, prepared through a PVA and CA impregnate cross-linking process, were investigated. The fabricated composite sponge exhibited an increase in compressive stress-strain proportional to the PVA cross-linking concentration, and its water retention capability was assessed through retention tests. Swelling tests for various solvents were conducted to evaluate the potential use of the sponge in diverse industries, revealing the highest swelling ratio in water. Pressure distribution measurements using prescale film indicated that the sponge's shock absorption capacity was enhanced by PVA cross-linking, leading to improved pressure dispersion.


Asunto(s)
Celulosa , Interacciones Hidrofóbicas e Hidrofílicas , Plantas Medicinales , Alcohol Polivinílico , Alcohol Polivinílico/química , Celulosa/química , Plantas Medicinales/química , Reactivos de Enlaces Cruzados/química , Elasticidad , Agua/química , Óxidos N-Cíclicos/química , Celulosa Oxidada/química
7.
Anticancer Res ; 44(8): 3349-3353, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-39060053

RESUMEN

BACKGROUND/AIM: Neskeep®, an absorbable polyglycolic acid spacer, has been developed as the optimal material for spacer placement surgery. However, preventing its severe adhesion is a crucial concern. Therefore, we aimed to identify an effective anti-adhesion agent for Neskeep® using rat models. MATERIALS AND METHODS: Animal experiments were performed using 60 rats, which underwent Neskeep® placement on the abdominal wall. Three types of anti-adhesion agents were employed, establishing four subgroups: Seprafilm®, INTERCEED®, AdSpray®, and only Neskeep® (control) groups. Rats were sacrificed on postoperative days 7, 14, and 28 to assess adhesion levels around the Neskeep® Macroscopic visual assessment with the Lauder score and histopathological evaluation were performed to assess the degree of adhesion. RESULTS: There were no significant differences in the proportion of Lauder scores on days 7 and 14 between the four groups. Histological evaluation revealed no significant differences between groups at any observation time. However, the mean Lauder scores at day 28 were 5.0, 1.6, 4.0, and 4.8 in the Neskeep®, Seprafilm®, INTERCEED®, and AdSpray® groups, respectively. The proportion of milder Lauder score was significantly higher in the Seprafilm® group on day 28. CONCLUSION: Seprafilm® may exhibit an anti-adhesive effect when used with Neskeep®.


Asunto(s)
Ácido Poliglicólico , Animales , Adherencias Tisulares/prevención & control , Adherencias Tisulares/patología , Ratas , Ácido Poliglicólico/química , Masculino , Ácido Hialurónico/farmacología , Implantes Absorbibles , Modelos Animales de Enfermedad , Pared Abdominal/cirugía , Pared Abdominal/patología , Ratas Sprague-Dawley , Celulosa Oxidada
8.
Int J Biol Macromol ; 274(Pt 2): 133497, 2024 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-38944090

RESUMEN

The monitoring of foodborne bacterial contamination requires simple and convenient biosensors. This work describes a novel paper-based colorimetric biosensor for the rapid and sensitive bacteria detection. The biosensor was constructed via the encapsulation of D-alanyl-D-alanine capped gold nanoparticles (DADA-AuNPs) in a modified paper that was fabricated by the freeze-drying of TEMPO-oxidized cellulose nanofibers/cationic guar gum composite hydrogel-modified filter paper. The results indicated that the size of DADA-AuNPs largely determined the color of their aqueous system and they exhibited light red to dark red as their size increased from around 6 to 36 nm. All these different sized DADA-AuNPs turned into colorless when encountered with either S. aureus or E. coli. In particular, the smaller the DADA-AuNPs size, the faster the discoloration. The encapsulation of DADA-AuNPs into modified paper negligibly changed their responsiveness towards bacteria. In comparison to the original filter paper and oven-dried hydrogel-modified filter paper, the freeze-dried hydrogel-modified paper was demonstrated to be a better substrate for the encapsulation of DADA-AuNPs since they could be loaded with a larger amount of DADA-AuNPs in a faster way and showed a better perceivable color. This work demonstrated a promising paper-based colorimetric biosensor for the facile and rapid detection of bacteria.


Asunto(s)
Técnicas Biosensibles , Colorimetría , Óxidos N-Cíclicos , Galactanos , Mananos , Nanopartículas del Metal , Nanofibras , Papel , Gomas de Plantas , Mananos/química , Gomas de Plantas/química , Nanofibras/química , Colorimetría/métodos , Galactanos/química , Técnicas Biosensibles/métodos , Óxidos N-Cíclicos/química , Nanopartículas del Metal/química , Oro/química , Staphylococcus aureus/aislamiento & purificación , Hidrogeles/química , Escherichia coli/aislamiento & purificación , Celulosa/química , Celulosa Oxidada/química , Bacterias
9.
Int J Biol Macromol ; 271(Pt 2): 132591, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38788873

RESUMEN

This study focused on synthesis of innovative hydrogels with electric field response from modified pineapple peel cellulose and hericium erinaceus chitosan and gelatin based on Schiff base reaction. A series of hydrogels were prepared by oxidized hydroxyethyl cellulose, gelatin and chitosan at different deacetylation degree via mild Schiff base reaction. Subsequently experiments towards the characterization of oxidized hydroxyethyl cellulose/gelatin/chitosan (OHGCS) hydrogel polymers were carried out by FTIR/XRD/XPS, swelling performances and electric response properties. The prepared hydrogels exhibited stable and reversible bending behaviors under repeated on-off switching of electric fields, affected by ionic strength, electric voltage and pH changes. The swelling ratio of OHGCS hydrogels was found reduced as deacetylation degree increasing and reached the maximum ratio âˆ¼ 2250 % for OHGCS-1. In vitro drug releasing study showed the both curcumin loading capacity and release amount of Cur-OHGCS hydrogels arrived about 90 % during 6 h. Antioxidation assessments showed that the curcumin-loaded hydrogels had good antioxidation activities, in which, 10 mg Cur-OHGCS-1 hydrogel could reach to the maximum of about 90 % DPPH scavenging ratio. These results indicate the OHGCS hydrogels have potentials in sensor and drug delivery system.


Asunto(s)
Ananas , Antioxidantes , Celulosa , Quitosano , Curcumina , Gelatina , Hidrogeles , Quitosano/química , Gelatina/química , Curcumina/química , Hidrogeles/química , Ananas/química , Celulosa/química , Celulosa/análogos & derivados , Antioxidantes/química , Antioxidantes/farmacología , Liberación de Fármacos , Basidiomycota/química , Portadores de Fármacos/química , Concentración de Iones de Hidrógeno , Electricidad , Celulosa Oxidada/química , Sistemas de Liberación de Medicamentos
10.
Carbohydr Polym ; 335: 122086, 2024 Jul 01.
Artículo en Inglés | MEDLINE | ID: mdl-38616071

RESUMEN

Recently, attention has been paid to cellulose nanofibers, such as 2,2,6,6-tetramethylpiperidine-1-oxyl-oxidized cellulose nanofibers (TOCN), as new bio-based materials. In addition, hydrophobized surface on TOCNs can be expected to provide new applications. Based on our previous finding that partially 2-deoxygenated (P2D)-amylose, which was synthesized by GP-catalyzed enzymatic copolymerization of D-glucal with α-d-glucose 1-phosphate (Glc-1-P) as comonomers, was hydrophobic, in this study, hydrophobization of surfaces on TOCNs was investigated by the GP-catalyzed enzymatic grafting of P2D-amylose chains on TOCNs. After maltooligosaccharide primers were modified on TOCNs, the GP-catalyzed enzymatic copolymerization of D-glucal with Glc-1-P was performed for grafting of P2D-amylose chains. 1H NMR spectroscopic analysis confirmed the production of P2D-amylose-grafted TOCNs with different 2-deoxyglucose/Glc unit ratios. The powder X-ray diffraction profiles of the products indicated that the entire crystalline structures were strongly affected by the unit ratios and chain lengths of the grafted polysaccharides. The SEM images observed differences in nanofiber diameter in the reaction solutions and surface morphology after film formation, due to grafting of P2D-amylose chains from TOCNs. The water contact angle measurement of a cast film prepared from the product indicated its hydrophobicity.


Asunto(s)
Celulosa Oxidada , Nanofibras , Celulosa , Amilosa , Gluconato de Calcio
11.
Carbohydr Polym ; 333: 121947, 2024 Jun 01.
Artículo en Inglés | MEDLINE | ID: mdl-38494214

RESUMEN

The rapid development of hydrogels has garnered significant attention in health monitoring and human motion sensing. However, the synthesis of multifunctional conductive hydrogels with excellent strain/pressure sensing and photoresponsiveness remains a challenge. Herein, the conductive hydrogels (BPTP) with excellent mechanical properties, fatigue resistance and photoresponsive behavior composed of polyacrylamide (PAM) matrix, 2,2,6,6-tetramethylpiperidin-1-yloxy-oxidized cellulose nanofibers (TOCNs) reinforcement and polydopamine-modified black phosphorus (BP@PDA) photosensitizer are prepared through a facile free-radical polymerization approach. The PDA adhered to the BP surface by π-π stacking promotes the optical properties of BP while also preventing BP oxidation from water. Through hydrogen bonding interactions, TOCNs improve the homogeneous dispersion of BP@PDA nanosheets and the mechanical toughness of BPTP. Benefiting from the synergistic effect of PDA and TOCNs, the conductive BPTP integrates superior mechanical performances, excellent photoelectric response and photothermal conversion capability. The BPTP-based sensor with high cycling stability demonstrates superior strain sensitivity (GF = 6.0) and pressure sensing capability (S = 0.13 kPa-1) to monitor various human activities. Therefore, this work delivers an alternative construction strategy for generating high-performance conductive hydrogels as multifunctional wearable sensors.


Asunto(s)
Celulosa Oxidada , Dispositivos Electrónicos Vestibles , Humanos , Conductividad Eléctrica , Hidrogeles , Enlace de Hidrógeno
12.
J Mater Chem B ; 12(14): 3453-3468, 2024 Apr 03.
Artículo en Inglés | MEDLINE | ID: mdl-38505998

RESUMEN

In this work, we have demonstrated agar and oxidized bacterial cellulose cryogels as a potential hemostatic dressing material. TEMPO-oxidized bacterial cellulose (OBC) was incorporated into the agar matrix, improving its mechanical and hemostatic properties. The oxidation of bacterial cellulose (BC) was evidenced by chemical characterization studies, confirming the presence of carboxyl groups. The in vitro blood clotting test conducted on agar/OBC composite cryogels demonstrated complete blood clotting within 90 seconds, indicating their excellent hemostatic efficacy. The cryogels exhibited superabsorbent properties with a swelling degree of 4200%, enabling them to absorb large amounts of blood. Moreover, the compressive strength of the composite cryogels was appreciably improved compared to pure agar, resulting in a more stable physical structure. The platelet adhesion test proved the significant ability of the composite cryogels to adhere to and aggregate platelets. Hemocompatibility and cytocompatibility tests have verified the safety of these cryogels for hemostatic applications. Finally, the material exhibited remarkable in vivo hemostatic performance, achieving clotting times of 64 seconds and 35 seconds when tested in the rat tail amputation model and the liver puncture model, respectively. The experiment results were compared with those of commercial hemostat, Axiostat, and Surgispon, affirming the potential of agar/OBC composite cryogel as a hemostatic dressing material.


Asunto(s)
Celulosa Oxidada , Hemostáticos , Ratas , Animales , Hemostáticos/farmacología , Hemostáticos/química , Celulosa Oxidada/farmacología , Criogeles/farmacología , Criogeles/química , Agar , Celulosa/farmacología
13.
Int J Biol Macromol ; 264(Pt 1): 130633, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38447835

RESUMEN

Efficiently addressing the challenge of leakage is crucial in the advancement of solid-liquid phase change thermal storage composite materials; however, numerous existing preparation methods often entail complexity and high energy consumption. Herein, a straightforward blending approach was adopted to fabricate stable phase change nanocomposites capitalizing on the interaction between TEMPO-oxidized cellulose nanofibers (TOCNF) and polyethylene glycol (PEG) molecules. By adjusting the ratio of TOCNF to PEG and the molecular weights of PEG, TOCNF/PEG phase change composites (TPCC) with customizable phase transition temperature (40.3-59.1 °C) and high phase transition latent heat (126.3-172.1 J/g) were obtained. The TPCC of high-loaded PEG (80-95 wt%) ensured a leakage rate of less than 1.7 wt% after 100 heating-cooling cycles. Moreover, TPCC exhibits excellent optical properties with a transmittance of over 90 % at room temperature and up to 96 % after heating. The thermal response analysis of TPCC demonstrates exceptional thermal-induced flexibility and good thermal stability, as well as recyclability and reshaping ability. This study may inspire others to design bio-based phase change composites with potential applications in thermal energy storage and management of smart-energy buildings, photothermal response devices, and waste heat-generating electronics.


Asunto(s)
Celulosa Oxidada , Nanofibras , Celulosa , Calor , Temperatura , Polietilenglicoles
14.
NanoImpact ; 34: 100504, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38537806

RESUMEN

Ecotoxicity data on cellulose nanofibers (CNFs) are limited despite their wide potential applications prospects, such as structural and packaging materials, filters, coatings, foods, and cosmetics. In this study, toxicity tests of 2,2,6,6-tetramethylpiperidine-1-oxyl radical (TEMPO)-oxidized CNFs (TEMPO-CNFs), which are one of the major CNF products commercially available in Japan, on the green alga Raphidocelis subcapitata were conducted. As nanomaterials are considered difficult-to-test substances, the Organisation for Economic Co-operation and Development has released a guidance document that provides considerations regarding ecotoxicity tests of nanomaterials. In the algal growth inhibition tests of TEMPO-CNFs, there were specific issues to be examined, including the effects of medium components on the characteristics of TEMPO-CNFs, CNF interference with algal density measurements, algal interference with CNF measurements, and the effects of ion concentration changes in the test medium by the addition of CNFs on algal growth. To examine these issues, we conducted preliminary studies and established a suitable test method for algal growth inhibition tests of TEMPO-CNFs. We confirmed that the components in the medium for algal growth inhibition tests had negligible effects on the characteristics (zeta-potential, viscosity, and morphology) and concentration stability of TEMPO-CNFs and that in vitro and in vivo fluorescence measurements were applicable for estimating the algal densities, without interference by TEMPO-CNFs. In contrast, we observed that the grown algae interfered with the CNF concentration measurements. Therefore, we established a method to correct the measured CNF concentrations by estimating the algal contribution. Furthermore, we found that the nutrient salt concentrations in the medium changed due to interactions with CNFs; however, this change did not affect algal growth. Based on the results of the preliminary studies, algal growth inhibition tests of TEMPO-CNFs were conducted using in vitro and in vivo fluorescence measurements, along with measurements of CNFs and ion concentrations in the test dispersions. The test results showed that no growth inhibition was observed on growth rate or yield even at the maximum CNF concentration of 100 mg/L, suggesting that the ecological effect of TEMPO-CNFs on algae was relatively low. The results of this study will be valuable for conducting ecotoxicity assessments on additional CNFs and comparable nanomaterials in future studies.


Asunto(s)
Óxidos N-Cíclicos , Nanofibras , Nanofibras/química , Óxidos N-Cíclicos/farmacología , Óxidos N-Cíclicos/química , Chlorophyta/efectos de los fármacos , Chlorophyta/crecimiento & desarrollo , Celulosa/química , Celulosa Oxidada/farmacología , Celulosa Oxidada/química , Pruebas de Toxicidad/métodos , Oxidación-Reducción
15.
Carbohydr Polym ; 332: 121931, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38431421

RESUMEN

Lumpectomy plus radiation is a treatment option offering better survival than conventional mastectomy for patients with early-stage breast cancer. However, successive radioactive therapy remains tedious and unsafe with severe adverse reactions and secondary injury. Herein, a composite hydrogel with pH- and photothermal double-sensitive activity is developed via physical crosslinking. The composite hydrogel incorporated with tempo-oxidized cellulose nanofiber (TOCN), polyvinyl alcohol (PVA) and a polydopamine (PDA) coating for photothermal therapy (PTT) triggered in situ release of doxorubicin (DOX) drug was utilized to optimize postoperative strategies of malignant tumors inhibition. The incorporation of TOCN significantly affects the performance of composite hydrogels. The best-performing TOCN/PVA7 was selected for drug loading and polydopamine coating by rational design. In vitro studies have demonstrated that the composite hydrogel exhibited high NIR photothermal conversion efficiency, benign cytotoxicity to L929 cells, pH-dependent release profiles, and strong MCF-7 cell inhibitory effects. Then the TOCN/PVA7-PDA@DOX hydrogel is implanted into the tumor resection cavity for local in vivo chemo-photothermal synergistical therapy to ablate residue tumor tissues. Overall, this work suggests that such a chemo-photothermal hydrogel delivery system has great potential as a promising tool for the postsurgical management of breast cancer.


Asunto(s)
Neoplasias de la Mama , Celulosa Oxidada , Hipertermia Inducida , Humanos , Femenino , Neoplasias de la Mama/tratamiento farmacológico , Neoplasias de la Mama/metabolismo , Terapia Fototérmica , Hidrogeles/química , Fototerapia , Mastectomía , Doxorrubicina/farmacología , Doxorrubicina/uso terapéutico , Concentración de Iones de Hidrógeno
16.
Int J Biol Macromol ; 264(Pt 2): 130675, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38462109

RESUMEN

The study aimed to develop a multifunctional wound dressing with enhanced antibacterial properties and wound healing promotion. The synthesis process involved preparing oxidized regenerated cellulose (ORC) following a modified procedure, synthesizing chitosan/silver nanoparticles (CS/Ag NPs) via an in-situ reduction method, and subsequently preparing ORC/CS/Lys@Ag NPs hydrogels. Characterization techniques including FTIR, XRD, SEM, and EDS were employed to analyze functional groups, lattice structure, morphology, and elemental composition. Gelation time, swelling behavior, water retention, mechanical properties, viscosity, self-healing capacity, rheological behavior, oxygen permeability, in vitro degradation, release of Ag+, and antibacterial properties were evaluated using various experimental methods. Results indicated that the novel wound dressing has the capability to evenly distribute Ag NPs to effectively counteract bacteria. It can maintain moist conditions for 86 h, resist a sturdy mechanical pressure of 11.3 KPa, and degrade by 11.045 % ± 0.429 within 8 h. Combining its efficient gas exchange abilities, self-repairing function, and biocompatibility, almost full recovery was observed in injured mouse skin within 13 days, highlighting its promising clinical utility.


Asunto(s)
Celulosa Oxidada , Celulosa , Quitosano , Nanopartículas del Metal , Ratones , Animales , Plata/química , Hidrogeles/farmacología , Hidrogeles/química , Celulosa Oxidada/farmacología , Lisina , Cicatrización de Heridas , Nanopartículas del Metal/química , Estudios Prospectivos , Antibacterianos/farmacología , Antibacterianos/química , Vendajes , Quitosano/química
17.
Int J Biol Macromol ; 264(Pt 2): 130770, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38467230

RESUMEN

Traditional adhesives easily release toxic gases during the preparation process or apply to wood composite products, which have adverse effects on the human body and the environment. Herein, an all-water-based high-performance wood adhesive is prepared using TEMPO-oxidized cellulose nanofiber (TOCNF), acrylamide (AM), and tannic acid (TA) through free radical polymerization. Different characteristics of the prepared composites, including morphology, injectability, and adhesion properties, have been investigated. Results showed that the TA/TOCNF/PAM composite has excellent injectability. The addition of TA can enhance the lap shear strength of the TA/TOCNF/PAM composites and with the increment of TA content, the lap shear strength gradually decreases. The formation of effective hydrogen bonds and Van der Waals interaction among the rich functional groups in the composite, lead to strong lap shear strength on different substrates. The composite with 5.0 g of AM, 5.0 g of the TOCNF suspension and 0.1 g TA possesses a high lap shear strength of 10.5 MPa on wood and 1.5 MPa on aluminium. Based on strong adhesion properties and excellent injectability, the TA/TOCNF/PAM composites have great potential in the furniture construction and building industries.


Asunto(s)
Celulosa Oxidada , Nanofibras , Polifenoles , Humanos , Adhesivos/química , Celulosa/química , Nanofibras/química , Madera/química , Agua/análisis , Celulosa Oxidada/análisis
18.
Int J Biol Macromol ; 265(Pt 1): 130571, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38467226

RESUMEN

Nanocatalysts tend to aggregate and are difficult to recycle, limiting their practical applications. In this study, an environmentally friendly method was developed to produce cellulose beads for use as supporting materials for Cu-based nanocatalysts. Cellulose beads were synthesized from a water-in-oil emulsion using cellulose dissolved in an LiBr solution as the water phase and vegetable oil as the oil phase. Upon cooling, the gelation of the cellulose solution produced spherical cellulose beads, which were then oxidized to introduce surface carboxyl groups. These beads (diameter: 95-105 µm; specific surface area: 165-225 m2 g-1) have a three-dimensional network of nanofibers (width: 20-30 nm). Furthermore, the Cu2O nanoparticles were loaded onto oxidized cellulose beads before testing their catalytic activity in the reduction of 4-nitrophenol using NaBH4. The apparent reaction rate constant increased with increasing loading of Cu2O nanoparticles and the conversion efficiency was >90 %. The turnover frequency was 376.2 h-1 for the oxidized cellulose beads with the lowest Cu2O loading, indicating a higher catalytic activity compared to those of other Cu-based nanoparticle-loaded materials. In addition to their high catalytic activity, the cellulose beads are reusable and exhibit excellent stability.


Asunto(s)
Celulosa Oxidada , Nanopartículas , Celulosa , Emulsiones , Aceites de Plantas , Agua
19.
Int J Biol Macromol ; 265(Pt 1): 130851, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38484821

RESUMEN

The wound dressings' lack of antioxidant and antibacterial properties, and delayed wound healing limit their use in wound treatment and management. Recent advances in dressing materials are aimed at improving the limitations discussed above. Therefore, the aim of this study includes the preparation and characterization of oxidized hydroxyethyl cellulose (OHEC) and ferulic acid-grafted chitosan (CS-FA) hydrogel loaded with green synthesized selenium nanoparticles (Se NPs) (OHEC-CS-FA-Se NPs named as nanohydrogel) for diabetic wound healing. The structure and properties of the hydrogel was characterized by FTIR, FE-SEM, HR-TEM, EDAX, UV-Vis spectrophotometry, XRD, DLS, zeta potential and rheological studies. The findings of these experiments demonstrate that nanohydrogel possesses a variety of outstanding qualities, including an optimal gel time, good swelling characteristics, a fair water retention rate, a good degradation rate, and strong mechanical stability. Nanohydrogel has been shown to have a synergistic impact by significantly increasing antioxidant activity by scavenging ABTS and DPPH radicals. The nanohydrogel's strong biocompatibility was confirmed by cytocompatibility testing using L929 mouse fibroblast cells. In addition, the wound healing potential of nanohydrogel was tested on L929 cells by an in vitro scratch assay and the nanohydrogel showed a wound closure rate of 100 % after 12 h. In addition to this study, nanohydrogel has demonstrated significant antimicrobial properties against human and wound infection causing pathogens such as Bacillus subtilis, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. In the animal model, almost complete diabetic wound healing was achieved on day 14 after application of the nanohydrogel. The results obtained indicate that the multifunctional bioactive nature of OHEC-CS-FA-Se NPs showed exceptional antioxidant and antibacterial potential for the treatment of infected and chronic wounds.


Asunto(s)
Celulosa Oxidada , Quitosano , Diabetes Mellitus , Staphylococcus aureus Resistente a Meticilina , Selenio , Ratones , Animales , Humanos , Quitosano/química , Hidrogeles/química , Antioxidantes/farmacología , Antioxidantes/química , Cicatrización de Heridas , Antibacterianos/química , Diabetes Mellitus/tratamiento farmacológico , Celulosa
20.
Int J Biol Macromol ; 263(Pt 2): 130087, 2024 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-38342262

RESUMEN

UV protection has become crucial as increasing environmental pollution has led to the destruction of the ozone layer, which has a weakened ability to block UV rays. In this paper, we successfully prepared cellulose-based biomass films with high UV shielding effect, high transparency and high tensile strength by graft-modifying oxidized cellulose nanocellulose (TOCN) with folic acid (FA) and borrowing vacuum-assisted filtration. The films had tunable UV shielding properties depending on the amount of FA added. When the FA addition was 20 % (V/V), the film showed 0 % transmittance in the UV region (200-400 nm) and 90.61 % transmittance in the visible region (600 nm), while the tensile strength was up to 150.04 MPa. This study provides a new integrated process for the value-added utilization of nanocellulose and a new route for the production of functional biomass packaging materials. The film is expected to be applied in the field of food packaging with UV shielding.


Asunto(s)
Celulosa Oxidada , Celulosa , Resistencia a la Tracción
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