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1.
AAPS PharmSciTech ; 23(1): 51, 2022 Jan 10.
Artículo en Inglés | MEDLINE | ID: mdl-35013801

RESUMEN

Nanofibers have many promising biomedical applications. They can be used for designing transdermal and dermal drug delivery systems. This project aimed to prepare and characterize polyvinylpyrrolidone-based nanofibers as a dermal and transdermal drug delivery system using pioglitazone. Pioglitazone is an oral antidiabetic drug. In addition, it can act as an inflammatory process modulator, making it a good candidate for managing different skin inflammatory conditions such as atopic dermatitis, skin ulcers, and diabetic foot wound healing. Several nanofiber formulations were prepared using the electrospinning method at different drug loadings, polyvinylpyrrolidone concentrations, and flow rates. A cast film with the exact composition of selected nanofiber formulations was prepared as a control. Nanofibers were characterized using a scanning electron microscope to calculate the diameter. Fourier-transform infrared spectroscopy, differential scanning calorimetry, thermogravimetric analysis, and powder X-ray diffraction were performed for physical and biochemical characterizations. In vitro release, drug loading efficiency, and swelling studies were performed. Ex vivo permeation studies were performed using Franz diffusion cells with or without applying a solid microneedle roller. Round uniform nanofibers with a smooth surface were obtained. The diameter of nanofibers was affected by the drug loading and polymer concentration. Fourier-transform infrared spectra showed a potential physical interaction between the drug and the polymer. According to X-ray diffraction, pioglitazone existed in an amorphous form in prepared nanofibers, with partial crystallinity in the casted film. Nanofibers showed a higher swelling rate compared to the casted film. The drug dissolution rate for nanofibers was 2.3-folds higher than the casted films. The polymer concentration affected the drug dissolution rate for nanofibers; however, drug loading and flow rate did not affect the drug dissolution rate for nanofibers. The application of solid microneedles slightly enhances the total amount of drug permeation. However, it did not affect the flux of the drug through the separated epidermis layer for pioglitazone. The drug permeation flux in nanofibers was approximately five times higher than the flux of the casted film. It was observed that pioglitazone is highly retained in skin layers. Graphical abstract.


Asunto(s)
Dermatitis Atópica , Nanofibras , Liberación de Fármacos , Humanos , Pioglitazona , Povidona
2.
Food Chem ; 371: 131372, 2022 Mar 01.
Artículo en Inglés | MEDLINE | ID: mdl-34808772

RESUMEN

To investigate antibacterial properties and application in food preservation of nanofibrous films (NFs), baicalin-liposomes (BCL-LPs) were loaded into polyvinyl alcohol-chitosan (PVA-CS) substrates to form NFs using electrospinning technology. The microstructure and phase identification of the NFs were characterized. The antibacterial properties and cytotoxicity of NFs were determined. The preservation of the NFs to mushrooms was evaluated. The results showed that smooth and uniform NFs were formed through molecular interaction between BCL-LPs and PVA-CS matrix. The NFs exhibited good antibacterial effects on Escherichia coli and Staphylococcus aureus due to the bacterial destruction resulting from the BCL delivery to bacterial cells by liposomes. In addition, the NFs were compatible with L929 fibroblasts. The BCL-LPs/PVA-CS NFs inhibited weight loss, browning, rancidity and bacterial growth as well as maintained the nutrients of mushrooms. The results show BCL-LPs/PVA-CS NFs possessed effective antibacterial properties, non-cytotoxicity and preservation performance, indicating the potential utilization as food-active packing.


Asunto(s)
Agaricales , Quitosano , Nanofibras , Antibacterianos/farmacología , Flavonoides , Liposomas , Alcohol Polivinílico
3.
J Colloid Interface Sci ; 608(Pt 1): 931-941, 2022 Feb 15.
Artículo en Inglés | MEDLINE | ID: mdl-34785468

RESUMEN

Conductive polymer nanofiber composites (CPNCs) based wearable sensing electronics have aroused great attention of scientists in recent years. However, it is still difficult to obtain CPNCs with good water proof, excellent durability, and multiple sensing performance. Herein, we develop a multifunctional CPNC with a wrinkled reduced graphene oxide (RGO) shell and polymer nanofiber core, which is prepared by ultrasonication induced decoration of RGO onto the pre-stretched polyurethane (PU) nanofibers, followed by the release of the strain. The RGO assembly with a wrinkled structure not only greatly increases the surface roughness and thus the hydrophobicity but also enhances the strain sensing sensitivity (with a gauge factor of 154.8 in the strain range of 85%-100%) of the nanofibrous membrane. The obtained CPNC strain sensor also shows excellent sensing durability (over 1000 cycles) and can be used for body motion monitoring. The CPNC shows a negative temperature coefficient effect, which holds promising applications in high performance temperature sensors.


Asunto(s)
Grafito , Nanofibras , Dispositivos Electrónicos Vestibles , Temperatura
4.
Food Chem ; 366: 130586, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34311229

RESUMEN

In this study, the gluten/zein nanofibrous films were fabricated by blending electrospinning and then glycated with xylose via Maillard reaction. The average fiber diameter of the gluten film decreased from 551 to 343 nm with the increasing ratio of zein, but increased significantly to a range of 717-521 nm after glycation, which induced a higher thermal stability of the nanofibers with an order to disorder transition. The glycated composite films showed the reduced water vapor permeability and improved water stability with a stiffer and more elastic network structure, due to the enhanced intermolecular entanglements and interactions between polymer chains. The results from this work suggested that the composite gluten/zein electrospun films may be glycated via Maillard reaction to obtain desirable physical properties for active food-packaging applications.


Asunto(s)
Nanofibras , Zeína , Embalaje de Alimentos , Glútenes , Polímeros
5.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112181, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34742023

RESUMEN

In this study, we investigated the application of poly (lactic acid-co-glycolic acid) in the rat Achilles tendon injury model for the prevention or alleviation of peritendinous adhesion and guidance of Achilles tendon regeneration. In the study, 48 rats were used and the rats were randomized by closed envelope method and divided into 4 mating groups in groups of 12. Left Achilles tendons of the non-PLGA-treated control group (groups 1 and 2) were cut and repaired. In the PLGA-treated groups (groups 3 and 4) the left Achilles tendons were cut and repaired, then PLGA bioabsorbable material was wrapped around the repair line. The rats in the 1st and 3rd groups were sacrificed at the end of the 1st month, and the rats in the 2nd and 4th groups at the end of the 2nd month. The degree of tendon adhesion in the Group 3 was lower in comparison with Group 1. Similarly, compared with Group 2, the degree of tendon adhesion in the Group 4 was lower. Inflammatory density, vascularization and fibrosis were higher in the experimental group. When the Group 3 and Group 1, and Group 2 and Group 4 were compared, adhesion length (p = 0.004, p = 0.041), adhesion characteristics (p = 0.049, p = 0.039) and adhesion severity (p = 0.007, p = 0.025) were found have statistically significant tendon healing in the PLGA-treated group, respectively. Significant difference was observed in inflammatory cell density, vascular density and fibrosis for Group 1 and Group 3, (p = 0.027, p = 0.041, p = 0.002), respectively. Similarly, significant difference was observed in inflammatory cell density, vascular density and fibrosis for Group 2 and Group 4, (p = 0.002, p = 0.027, p = 0.011), respectively. As a result, it was considered that poly (lactic acid-co-glycolic acid) material significantly reduces peritendinous adhesions, and this effect could occur with the vascular density, inflammatory density and fibrosis as indicated in histopathological examination. These data suggest that PLGA membrane has good biocompatibility and alleviates tendon adhesion after injury.


Asunto(s)
Tendón Calcáneo , Nanofibras , Implantes Absorbibles , Tendón Calcáneo/patología , Tendón Calcáneo/cirugía , Animales , Glicolatos , Ácido Láctico , Ratas , Adherencias Tisulares/patología , Adherencias Tisulares/prevención & control
6.
J Mech Behav Biomed Mater ; 125: 104975, 2022 01.
Artículo en Inglés | MEDLINE | ID: mdl-34823087

RESUMEN

The subject of this paper is to develop a highly conductive Graphene nanoplatelets (GNPs)-Chitosan (CS)/Polyvinyl Alcohol (PVA) (GNPs-CP) nanofibers with excellent mechanical properties. An experimental study was designed to produce nanofibers based on CP nanofibers as matrix and GNPs as reinforcement materials. The microstructure and the surface morphology of the electrospun nanofibers along with their electrical and mechanical properties were examined to study the effect of GNPs content. The SEM results showed that the gradual increase in GNPs content led to a porous web like morphology with no bead. There is a decrease in the diameter of nanofibers by increasing the concentration of GNPs to 1 wt% GNPs from 370 ± 40 nm for CP blend to 144 ± 18 nm for 1 wt% GNPs. Transmission electron microscopy results depicted that GNPs were dispersed uniformly confirmed by the absence of characteristic peak of graphite at 2θ = 26.5°. Attenuated Total Reflectance-Fourier Transform Infrared Spectroscopy results indicate the occurrence of a few interactions between GNPs and CP matrix. Nitrogen adsorption/desorption measurement demonstrated that increasing GNPs content increased the specific surface area of nanofibers from 238.377 to 386.708 m2/g for 0 and 1 wt% GNPs content. The test results also show that the presence of GNPs considerably enhances tensile strength, elastic modulus and electrical conductivity. Furthermore, the toughness of GNPs-CP nanofibers including 1 wt% GNPs significantly improved (12-fold) compared to the one for CP nanofibers. So, the proposed composite provides a decent functionality for nanofibers as scaffolds in tissue engineering applications.


Asunto(s)
Quitosano , Grafito , Nanofibras , Conductividad Eléctrica , Alcohol Polivinílico
7.
J Environ Manage ; 301: 113908, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34626949

RESUMEN

The direct discharge of significant amounts of polluted water into water bodies causes adverse ecological and human health effects. This severe deterioration in water quality creates significant challenges to meet the growing demand for clean water. Therefore, the world urgently needs environmentally friendly advanced technology to overcome this global crisis. In this regard, nanofiber-based membrane filtration is a promising technique in wastewater remediation because of their huge surface area, extremely porous structure, amenable pore size/pore size distribution, variety of material choices, and flexibility to modification with other functional materials. However, despite their unique properties, fouling, poor mechanical properties, shrinkage, and deformation are major drawbacks of nanofiber membranes for treating wastewater. This review presents a comprehensive overview of nanofiber membranes' fabrication and function in water purification applications as well as providing novel approaches to overcoming/alleviating the mentioned disadvantages. The review first presents nanofiber membrane preparation methods, focusing on electrospinning as a versatile and viable technique alongside discussing the parameters controlling nanofiber morphology. Afterward, the functionalization of nanofiber membranes by combining them with other nanomaterials, such as metal and metal-oxide nanoparticles, carbon nanotubes, metal-organic frameworks, and biomolecules, were demonstrated and discussed. In addition, nanofiber membranes functionalized with microorganisms were highlighted. Finally, we introduced and discussed in detail the most relevant and recent advances in nanofiber applications in wastewater treatment in the context of removing different pollutants (e.g., heavy metals, nutrients, radioactive elements, pharmaceuticals, and personal care products, dyes, and pesticides). Moreover, the promising antimicrobial ability of nanofiber membranes in removing microorganisms from wastewater has been fully underscored. We believe this comprehensive review could provide researchers with preliminary data and guide both researchers and producers engaged in the nanofiber membrane industry, letting them focus on the research gaps in wastewater treatment.


Asunto(s)
Metales Pesados , Nanofibras , Nanotubos de Carbono , Purificación del Agua , Humanos , Aguas Residuales
8.
Talanta ; 236: 122880, 2022 Jan 01.
Artículo en Inglés | MEDLINE | ID: mdl-34635260

RESUMEN

A novel aptamer-functionalized metal-organic framework nanofibrous composite (viz. PAN/UiO@UiO2-N3-aptamer) with a high aptamer coverage density was proposed based on the electrospinning and seeded growth method, and used for specific affinity recognition of trace Microcystin-LR (MC-LR). Heterobifunctional ligand was used to modify the metal-organic framework nanoparticles (MOF NPs) surface, which could passivate the MOF surface with respect to unmodified DNA, followed by coupling massive aptamers on MOF of the solid-phase microextraction (SPME) fiber using click chemistry. Characterizations including morphology, spectra analysis, mechanical stability, binding capacity and specificity were fulfilled. Applied to the analysis of MC-LR, the good selective and sensitive recognition were obtained with the detection limit as low as 0.003 ng/mL, which was better than most non-specific SPME or solid-phase extraction (SPE) protocols. The stability and reproducibility were acceptable, and the intra-day, inter-day and column-to-column relative standard deviations (RSDs) for the recovery of MC-LR were gained in the range from 2.5% to 14.3%, respectively. Satisfactory recoveries of MC-LR in environmental water samples were measured as 96.3 ± 4.7% - 98.9 ± 2.7% (n = 3) in tap water, 94.4 ± 2.5% - 96.1 ± 3.5% (n = 3) in pond water, and 97.0 ± 2.1% - 97.9 ± 3.1% (n = 3) in river water, respectively. This work demonstrated that the electrospun nanofibrous composite with massive aptamers would be a better alternative for ultra-trace MC-LR detection with good selectivity, matrix-resistance ability and high resolution.


Asunto(s)
Aptámeros de Nucleótidos , Estructuras Metalorgánicas , Nanofibras , Toxinas Marinas , Microcistinas , Reproducibilidad de los Resultados
9.
Int J Food Microbiol ; 361: 109460, 2022 Jan 16.
Artículo en Inglés | MEDLINE | ID: mdl-34785387

RESUMEN

A series of alkyl gallates were evaluated for the antibacterial activity against two common Gram-negative foodborne bacteria (Pseudomonas fluorescens and Vibrio parahaemolyticus) associated with seafood. The length of the alkyl chain plays a pivotal role in eliciting their antibacterial activities and octyl gallate (OG) exerted an excellent inhibitory efficacy. To extend the aqueous solubility, stability, and bactericidal properties of octyl gallate (OG), an inclusion complex between OG and ß-cyclodextrin (ßCD), OG/ßCD, was prepared and identified with various methods including X-ray diffraction (XRD), differential scanning calorimeter (DSC) and Fourier transform infrared spectroscopy (FTIR). Furthermore, the enhanced inhibitory effect and potential antibacterial mechanism of OG/ßCD against two Gram-negative and Gram-positive foodborne bacteria were comprehensively investigated. The results show that OG/ßCD could function against bacteria through effectively damaging the membrane, permeating into cells, and then disturbing the activity of the respiratory electron transport chain to cause the production of high-level intracellular hydroxyl radicals. Moreover, the reinforced OG/ßCD-incorporated polylactic acid (PLA) nanofibers were fabricated using the electrospinning technique as food packaging to extend the Chinese giant salamander fillet's shelf life at 4 °C. This research highlights the antibacterial effectiveness of OG/ßCD in aqueous media, which can be used as a safe multi-functionalized food additive combined with the benefits of electrospun nanofibers to extend the Chinese giant salamander fillets shelf life by 15 d at 4 °C.


Asunto(s)
Nanofibras , Pseudomonas fluorescens , Vibrio parahaemolyticus , beta-Ciclodextrinas , Animales , Antibacterianos/farmacología , China , Ácido Gálico/análogos & derivados , Espectroscopía Infrarroja por Transformada de Fourier , Urodelos , beta-Ciclodextrinas/farmacología
10.
Chemosphere ; 286(Pt 2): 131731, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34388866

RESUMEN

Photocatalysis has gained attention as a viable wastewater remediation technique. However, the difficulty of recovering powder-based photocatalyst has often become a major limitation for their on-site practical application. Herein, we report on the successful in-situ preparation of a novel three-dimensional (3D) photocatalyst consisting of Cu2O/TiO2 loaded on a cellulose nanofiber (CNF)/reduced graphene hydrogel (rGH) via facile hydrothermal treatment and freeze-drying. The 3D macrostructure not only provides a template for the anchoring of Cu2O and TiO2 but also provides an efficient electron transport pathway for enhanced photocatalytic activity. The results showed that the Cu2O and TiO2 were uniformly loaded onto the aerogel framework resulting in the composites with large surface area with exposed actives sites. As compared to bare rGH, CNF/rGH, Cu2O/CNF/rGH and TiO2/CNF/rGH, the Cu2O/TiO2/CNF/rGH showed improved photocatalytic activity for methyl orange (MO) degradation. MO degradation pathway is proposed based on GC-MS analysis. The enhanced photoactivity can be attributed to the charge transfer and electron-hole separation from the synergistic effect of Cu2O/TiO2 anchored on CNF/rGH. In terms of their anti-bacterial activity towards Staphylococcus aureus and Escherichia coli, the synergistic effect of the Cu2O/TiO2 anchored on the CNF/rGH framework showed excellent activity towards the bacteria.


Asunto(s)
Grafito , Nanofibras , Antibacterianos/farmacología , Catálisis , Celulosa , Cobre , Hidrogeles , Titanio
11.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112151, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34687974

RESUMEN

In this research, lipase Km12 was immobilized on the glutaraldehyde-activated graphene oxide/chitosan/cellulose acetate nanofibers (GO/Chit/CA NFs) prepared by the electrospinning method. This immobilized lipase exhibited a higher activity value than the free lipase in the acidic pH region. This enzyme showed a 10 °C shift in the maximum temperature activity. Results displayed that the Vmax value of NFs-lipase was 0.64 µmol/min, while it was gained 0.405 µmol/min for the free lipase. The activity of NFs-lipase was reserved 100% after 10 min maintaining at 60 °C, in which the free lipase only kept 75% of its original activity. Moreover, a 20% enhancement in the lipase activity was observed for NFs-lipase after 180 min of incubation at 60 °C, compared to the free enzyme. Reusability studies exhibited that the immobilized lipase well-kept 80% of its original activity after 10 cycles of reusing. Results displayed that 14% of the protein was leaked from NFs-lipase at the same condition. Transesterification results indicated that the free lipase exhibited 65% and 85% conversation level of benzyl acetate after 12 and 24 h of incubation. Besides, the immobilized lipase showed 80% and 95% conversation level at the same condition. These results indicated the high performance of free and immobilized lipase in the production of benzyl acetate for applications in the perfume and cosmetic industries.


Asunto(s)
Quitosano , Nanofibras , Compuestos de Bencilo , Celulosa/análogos & derivados , Estabilidad de Enzimas , Enzimas Inmovilizadas/metabolismo , Glutaral , Grafito , Concentración de Iones de Hidrógeno , Lipasa/metabolismo , Temperatura
12.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112209, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34814101

RESUMEN

Biodegradable poly-(lactide-coε-caprolactone) (PLCL) scaffolds have opened new perspectives for tissue engineering due to their nontoxic and fascinating functionality. Herein, a black phosphorus-based biodegradable material with a combination of promising enhanced hydrophilicity, shape recovery and osteodifferentiation properties was proposed. First, amino black phosphorous (BP-NH2) was prepared by a simple ball milling method. Then, L-lysine-modified black phosphorous (L-NH-BP) was formed by hydrogen bonding between L-lysine and amino BP and integrated into PLCL to form PLCL/L-NH-BP composite fibers. The scaffolds had excellent shape recovery and shape fixity properties. Moreover, based on gene expression and protein level assessment, the scaffolds could enhance the expression of alkaline phosphatase (ALP) and bone morphogenetic protein 2 (BMP2), simultaneously improving the mineralization ability of bone mesenchymal stem cells. Specifically, this new composite material was experimentally verified to be degradable under mild conditions. This strategy provided new insight into the design of multifunctional materials for diverse applications.


Asunto(s)
Nanofibras , Caproatos , Dioxanos , Interacciones Hidrofóbicas e Hidrofílicas , Lactonas , Lisina , Fósforo , Poliésteres , Ingeniería de Tejidos , Andamios del Tejido
13.
Colloids Surf B Biointerfaces ; 209(Pt 2): 112218, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34801930

RESUMEN

Regeneration of urethral defects has been difficult in the clinic. To address it, the collagen/ poly (L-lactide-co-caprolactone) (P(LLA-CL)) nanoyarn scaffold delivering adipose-derived stem cells' exosomes (ADSC-exos) was fabricated. The multipotential differentiation potential of ADSCs were confirmed by Adipogenic, osteogenic, and chondrogenic differentiation. The 3-(4,5-dimethylthiazol-2-yl)- 2,5-diphenyltetrazolium bromide assay shows that 50% concentration of ADSC-exos nanoyarn scaffold dramatically enhanced the cell viability of fibroblasts. The ADSC-exos nanoyarn scaffold for human foreskin fibroblasts (HFFs) and human urethral scar fibroblasts (HSFs) shows good biocompatibility: theproduction of inflammatory factors IL-6 and Col 1A1 was less, indicating that ADSC-exos had the minimal inflammatory effect of cells. Besides, the cells on the ADSC-exos nanoyarn scaffold did not appear to contribute to DNA damage in the same way as the normal cell's growth did. The HFFs seeding on the ADSC-exos nanoyarn scaffold shows a typical morphology of extending outwards. Urethral repair with ADSC-exos nanoyarn scaffold did not lead to either a sign of urethral stricture or scar formation after 4 weeks post-surgery. The deposition of collagen was less and the epithelial cells formed multiple layer epithelium. The treatment of ADSC-exos stimulated epithelization and vascularization. And the transition from an inflammatory state to a regenerative state was promoted. The ADSC-exos-treated group did not promote the over-proliferation of fibroblasts and the expression of Collagen I. Therefore, the ADSC-exos nanoyarn scaffold has evident, positive effects on wound healing and tissue fibrosis inhibition.


Asunto(s)
Exosomas , Nanofibras , Uretra , Tejido Adiposo , Colágeno , Humanos , Células Madre , Ingeniería de Tejidos , Cicatrización de Heridas
14.
Spectrochim Acta A Mol Biomol Spectrosc ; 268: 120691, 2022 Mar 05.
Artículo en Inglés | MEDLINE | ID: mdl-34896677

RESUMEN

Despite the adequacy of the endogenous steroid (progesterone) levels in biological functioning, elevated levels of progesterone hormone have several physiological effects that are amplified due to its direct and indirect uptake from the environment, food products, and medical therapy. So, it is much needed to evaluate the progesterone levels in environmental samples as well as for biological fluids. In this work, we focused on the development of the nano sensing probe for the selective detection of progesterone among the library of steroid hormones belonging to the class of female sex hormones. Herein, functionalization of dipeptide is carried out at N-terminal to produce N-functionalized dipeptide (SS3), and simultaneously, its self-assembly properties are explored. Furthermore, HR-TEM imaging was also performed to examine the morphology of the self-assembled architectures before and after the addition of the steroid hormone. To investigate the binding mechanism of the sensing probe, Fluorescence spectroscopy, Circular Dichroism (CD), MD-Simulation, and DFT studies were performed and studied in detail. Moreover, to check the potency of the real-time application of the developed nanoprobe, we have successfully determined the spiked concentration of progesterone levels in pharmaceutical and biological fluid samples with functional percentage recovery. Also, the stability and other competitive binding studies of the probe with the coexisting substances are performed to check the rationality of the sensing probe at physiological conditions.


Asunto(s)
Nanofibras , Peptidomiméticos , Preparaciones Farmacéuticas , Femenino , Humanos , Progesterona , Agua
15.
Methods Mol Biol ; 2375: 101-114, 2022.
Artículo en Inglés | MEDLINE | ID: mdl-34591302

RESUMEN

Tissue-engineered small-diameter vascular grafts are required to match mechanical properties as well as cellular and extracellular architecture of native blood vessels. Although various engineering technologies have been developed, the most reliable strategy highlights the needs for incorporating completely biological components and anisotropic cellular and biomolecular organization into the tissue-engineered vascular graft (TEVG). Based on the antithrombogenic, immunoregulatory, and regenerative properties of human mesenchymal stem cells (hMSCs), this chapter provides a step-by-step protocol for generating a completely biological and anisotropic TEVG that comprises of hMSCs and highly aligned extracellular matrix (ECM) nanofibers. The hMSCs were grown on an aligned nanofibrous ECM scaffold derived from an oriented human dermal fibroblast (hDF) sheet and then wrapped around a temporary mandrel to form a tubular assembly, followed by a maturation process in a rotating wall vessel (RWV) bioreactor. The resulting TEVG demonstrates anisotropic structural and mechanical properties similar to that of native blood vessels. A completely biological, anisotropic, and mechanically strong TEVG that incorporates immunoregulatory hMSCs is promising to meet the urgent needs of a surgical intervention for bypass grafting.


Asunto(s)
Células Madre Mesenquimatosas , Matriz Extracelular , Fibroblastos , Humanos , Nanofibras , Ingeniería de Tejidos , Andamios del Tejido
16.
Chemosphere ; 287(Pt 2): 132092, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34826888

RESUMEN

Superhydrophobic nanofibers have received prominent attention owing to their exceptional properties and researchers are focused on developing high-performing MD membranes. Herein, we fabricate superhydrophobic electrospun nanofibrous membranes using polyvinylidene fluoride (PVDF) solutions with silica nanoparticles (0 wt% to 6 wt%) to create multiscale (or hierarchical) surface roughness. For superhydrophobicity, the composite membranes (Si@PVDF) were subjected to a two-step modification that included acid pre-treatment and silanization with fluoroalkylsilane (FAS) compound of low surface energy. The acid pre-treatment enhances the hydroxyl group of SiO2 nanoparticles and create active sites in abundance for silanization. The modified membranes (FAS-Si@PVDF-A) having 6 wt% SiO2 showed excellent wetting resistance with water contact angle (WCA) up to 154.6 ± 2.2°, smaller average pore size of 0.27 ± 0.3 µm, and high liquid entry pressure (LEP) of 143 ± 4 kPa. It was observed, increasing silica content decreased the fiber diameter and average pore size and increased WCA and LEP of modified membranes. The modified superhydrophobic membranes gave stable permeate flux, exhibited strong wetting resistance and excellent salt rejection in vacuum membrane distillation (VMD) test. The optimal FAS-Si@PVDF-A membrane (6 wt% SiO2) of thickness 98 ± 5 µm produced a stable permeate flux of more than 11.5 kg m-2 h-1 and salt rejection as high as 99.9% after 22 h of continuous operation using NaCl solution (3.5 wt%) as feed. Therefore, this modification provided superhydrophobic membranes possessing robust anti-wetting properties with significant permeability and has encouraging application in membrane distillation for desalination.


Asunto(s)
Nanofibras , Purificación del Agua , Destilación , Interacciones Hidrofóbicas e Hidrofílicas , Membranas Artificiales , Polivinilos , Dióxido de Silicio , Vacio
17.
J Hazard Mater ; 422: 126835, 2022 01 15.
Artículo en Inglés | MEDLINE | ID: mdl-34391969

RESUMEN

Currently, industrial waste gas and oily wastewater are usually at high temperature and contain corrosive components (e.g., acid, alkali, oxidant, or high salt, etc.), presenting great challenges on filtration/separation materials. Here, a multi-purpose Poly(m-phenylene isophthalamide)/polyacrylonitrile/silica (PMIA/PAN/SiO2) nanofiber composite membrane with a high yield was prepared simply via electrospinning to satisfy the demands of air filtration and oil/water separation in complex environments. Under the synergy of PMIA, PAN and SiO2, the composite membrane possesses high PM0.3 removal capacity of 99.69%, robust purification ability against real smoke PM2.5, effective oil/water separation performance of > 99.6%, superior high temperature stability (about 250 °C) and excellent chemical resistance, showing the potential application in filtration/separation process under complex conditions. Moreover, the influence mechanism of SiO2 NPs on mechanical properties and filtration performance was systematically investigated through experiments and simulations, paving the way for future intensive research. This study provides an option for the facile and effective preparation of high-performance filtration/separation membranes applied in the field of dust filtration and oily wastewater separation, even in harsh environments.


Asunto(s)
Nanofibras , Purificación del Agua , Filtración , Dióxido de Silicio , Aguas Residuales
18.
Chemosphere ; 286(Pt 2): 131671, 2022 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-34352548

RESUMEN

The demand for air filter media at indoor and outdoor is increasing tremendously due to air pollution and especially for problems related to airborne particulate matter (PM). To realize that, here a class nanofiber air filter media with strong antibacterial activity, hydrophobic nature, high filtration efficiency with low pressure drop is prepared. Novel organic-inorganic nanocomposite nanofibers used in this work benefited for the multifunctional performance. Amorphous titanium dioxide (mTiO2) is utilized for air filtration application which exhibits excellent enhancement of PM2.5 filtration properties and antibacterial activity. The unique Poly (vinylpyrrolidone) (PVP)-mTiO2 nanofiber air filter media acquired hydrophobic nature with a large increase in water contact angle of 127° from 36°. The resulting free-standing nanofiber filters exhibit high PM2.5 filtration efficiency of >99.9% and low pressure drop of 39 Pa. Antibacterial activity of nanofibrous membrane has been rationally engineered by titanium oxide as the barrier to bacterial ingression. A long term of 160 h filtration test has proved PVP-mTiO2 nanofibers air filter media holds outstanding 99% filtration efficiency for PM2.5. This work takes forward a significant lead in design and production of high performance and very low pressure drop air filter media with a wide range of functional properties.


Asunto(s)
Filtros de Aire , Nanofibras , Filtración , Material Particulado , Titanio
19.
J Hazard Mater ; 421: 126775, 2022 01 05.
Artículo en Inglés | MEDLINE | ID: mdl-34358971

RESUMEN

Hydroquinone (HQ) and catechol (CC) are the two major dihydroxybenzene isomers, are considered one of the toxic pollutants in wastewater, which often coexisted and impede each other during sample identification. For practical analysis and simultaneous detection of HQ and CC in wastewater, we fabricate a hybrid electrochemical sensor with electrospun one-dimensional (1D) MnMoO4 nanofibers coupled with a few-layered exfoliated two-dimensional (2D) MXene. The facilitated abundant defective edges of 1D MnMoO4 and 2D MXene nanoarchitecture accelerated the effect of synergistic signal amplification and exhibited high electrocatalytic activity towards the oxidation of hydroquinone and catechol. MnMoO4-MXene-GCE showed oxidation potentials of 0.102 V and 0.203 V for hydroquinone and catechol, respectively. It revealed the distinguished and simultaneous detection range of 0.101 V with a strong anodic peak current. Noteworthily, the proposed 1D-2D hybridized MnMoO4-MXene-GCE sensor exhibited a wide linear response from 5 nM to 65 nM for hydroquinone and catechol. Moreover, it showed a low detection limit of 0.26 nM and 0.30 nM for HQ and CC with high stability, respectively. The feasible 1D-2D MnMoO4-MXene nanocomposite-based biosensor effectively detected hydroquinone and catechol in hazardous water pollutants using the differential pulse voltammetric technique with recovery values.


Asunto(s)
Técnicas Biosensibles , Nanocompuestos , Nanofibras , Electrodos , Aguas Residuales
20.
J Colloid Interface Sci ; 606(Pt 1): 261-271, 2022 Jan 15.
Artículo en Inglés | MEDLINE | ID: mdl-34390993

RESUMEN

Morphological and structural characteristics of semiconductors have a significant impact on their gas sensing characteristics. Reasonable design and synthesis of heterojunctions with special structures can effectively improve sensor performance. Herein, a cobalt oxide (Co3O4) nanofibers/cadmium sulfide (CdS) nanospheres hybrid was synthesized by an electrospinning method combined with a hydrothermal method to detect acetone gas. By adjusting loading amount of CdS, the sensing performance of CdS/Co3O4 sensor for acetone at room temperature (25 °C) was greatly ameliorated. In particular, the response of CdS/Co3O4 to 50 ppm acetone gas increased by 25% under 520 nm green light, meanwhile, the response/recovery time was shortened to 5 s/4 s. This is attributed to the heterojunction formed between CdS and Co3O4 as well as the influence of light excitation on the carrier concentration of the surfaces. Meanwhile, the unique high-porosity fiber structure and the catalytic action of cobalt ions also play an essential role in improving the performance. Furthermore, practical diabetic breath was experimentally simulated and proved the potential of the sensor in the future application of disease-assisted diagnosis.


Asunto(s)
Diabetes Mellitus , Nanofibras , Nanosferas , Acetona , Biomarcadores , Compuestos de Cadmio , Humanos , Sulfuros
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