Properties Of Nanofibers Research Articles

Pullulan nanofibrous films incorporated with W/O emulsions via microfluidic solution blow spinning technology

In this work, pullulan (PUL) nanofibrous films incorporated with water-in-oil emulsions (PE) were prepared by microfluidic blowing spinning (MBS). The microstructures of nanofibers were characterized by scanning electron microscopy (SEM), fourier transform infrared (FT-IR), and X-ray diffraction (XRD). With the addition of W/O emulsions, the thermal stability, mechanical, and water barrier properties of PUL nanofibers were improved. Increases in emulsion content significantly affected the antioxidant and antimicrobial properties of nanofibrous films. ABTS and DPPH free radical scavenging rates increased from 10.26 % and 8.57 % to 60.66 % and 57.54 %, respectively. The inhibition zone of PE nanofibers against E. coli and S. aureus increased from 11.00 to 20.00 and from 15.67 to 21.17 mm, respectively. In addition, we investigated the freshness effectiveness of PE nanofibrous films on fresh-cut apples. PE nanofibrous films significantly maintained the firmness, and reduced the weight loss and browning index of the fresh-cut apple, throughout the 4 days of storage. Thus, the PE nanofibrous films exhibited good potential to prolong the shelf life of fresh-cut fruit and promote the development of active food packaging.

Polyacrylonitrile-based carbon nanofiber electrode fabricated via electrospun for supercapacitor application

The versatile properties of electrospun carbon nanofibers gaining attention for electrode materials for supercapacitors. The heat treatment process of stabilization played an important role before the carbonization process in electrode fabrication. In the present study, electrospun stabilized polyacrylonitrile nanofiber (St PAN) and carbonized Polyacrylonitrile nanofiber (CNF) at minimum temperature were used as active mass for supercapacitor electrodes. Stabilized CNF nanofiber sample showed a reduction in nanofiber diameter with increased carbon percentage. XRD results showed increased crystallinity in the CNF sample as compared with the Stabilized PAN sample. Electrochemical characterization was performed to measure specific capacitance and to analyze the charge storage mechanism. The proportion of capacitive and diffusion-controlled contributions to energy storage was estimated using Dunn’s model. The results obtained demonstrated that, in comparison to the St PAN electrode, the CNF electrode exhibited a greater capacitive-controlled contribution. The CNF sample has shown an increased capacitive contribution of 82.3% as compared with the St PAN sample. This work provides a method for making electrospun carbon nanofiber-based electrodes as well as a methodical methodology for examining the charge storage process.

Development of cross‐linked polyvinyl alcohol/sodium caseinate/silver nanoparticle electrospun mats for antibacterial wound dressing

AbstractIn this study, nanofibers were produced by the electrospinning method by adding 1%, 3%, 5%, and 7% silver nanoparticles (Ag NPs) into the polyvinyl alcohol/sodium caseinate (60/40, w/w) mixture. Electrospun materials were cross‐linked by immersion in a glutaraldehyde bath. Thus, antibacterial wound dressings that could be used on exuding wounds were developed. According to the scanning electron microscopy images of nanofibers, the cross‐linking process by immersion method did not cause negative effects such as breakage or adhesion on the surface of fibers. The cross‐linking of nanofibers was demonstrated by the presence of acetal linkages by Fourier‐transform infrared spectroscopy analysis. The cross‐linking process significantly improved the thermal properties of the nanofibers. The lowest crystallinity calculated in the differential scanning calorimeter was observed in the 3% Ag NP‐added nanofiber with a value of 1.83%. It exhibited the lowest total soluble matter content with a value of 11.98% owing to its high cross‐linking density. In addition, the 3% Ag NP‐added nanofiber, which had the highest toughness and ductility, displayed the highest tensile stress with 3.5 MPa and the highest tensile strain with 7.53%. Moreover, it showed 78.11% cell viability on the L929 fibroblast cell line at the end of the 24th hour. It was indicated that although the electrospun mats maintained 100% antibacterial effectiveness, they could not be used as a wound dressing for 48 h. It was reported that only 3% Ag NP‐added nanofiber could be used as a 100% effective antibacterial wound dressing for both Escherichia coli and Staphylococcus aureus provided that it was renewed every 24 h. Consequently, it was notified that cross‐linking by the immersion method can be used in biomedical applications.Highlights The antibacterial effects of Ag NP‐doped PVA/NaCAS electrospun mats were significant. The cross‐linking process did not induce toxic effects some of the nanofibers. High cross‐linking density was observed in the nanofibers. The swelling property of nanofibers is a good feature required in an ideal wound dressing.

Preparation of bilayer tissue-engineered polyurethane/poly-L-lactic acid nerve conduits and their in vitro characterization for use in peripheral nerve regeneration

BackgroundDue to loss of peripheral nerve structure and/or function resulting from trauma, accidents, and other causes, peripheral nerve injuries continue to be a major clinical problem. These injuries can cause partial or total loss of sensory, motor, and autonomic capabilities as well as neuropathic pain. PNI affects between 13 and 23 out of every 100,000 people annually in developed countries. Regeneration of damaged nerves and restoration of function after peripheral nerve injury remain significant therapeutic challenges. Although autologous nerve graft transplantation is a viable therapy option in several clinical conditions, donor site morbidity and a lack of donor tissue often hinder full functional recovery. Biomimetic conduits used in tissue engineering to encourage and direct peripheral nerve regeneration by providing a suitable microenvironment for nerve ingrowth are only one example of the cutting-edge methods made possible by this field. Many innate extracellular matrix (ECM) structures of different tissues can be successfully mimicked by nanofibrous scaffolds. Nanofibrous scaffolds can closely mimic the surface structure and morphology of native ECMs of many tissues.MethodsIn this study, we have produced bilayer nanofibrous nerve conduit based on poly-lactic acid/polyurethane/multiwall carbon nanotube (PLA/PU/MWCNT), for application as composite scaffolds for static nerve tissue engineering. The contact angle was indicated to show the hydrophilicity properties of electrospun nanofibers. The SEM images were analyzed to determine the fiber’s diameters, scaffold morphology, and endometrial stem cell adhesion. Moreover, MTT assay and DAPI staining were used to show the viability and proliferation of endometrial stem cells.ResultsThe constructed bilayer PLA/PU/MWCNT scaffolds demonstrated the capacity to support cell attachment, and the vitality of samples was assessed using SEM, MTT assay, and DAPI staining technique.ConclusionsAccording to an in vitro study, electrospun bilayer PLA/PU/MWCNT scaffolds can encourage the adhesion and proliferation of human endometrial stem cells (hEnSCs) and create the ideal environment for increasing cell survival.

Improving rodents and humans cardiac cell maturity in vitro through polycaprolactone and polyurethane nanofibers

Currently, numerous studies are conducted using nanofibers as a scaffold for culture cardiac cells; however, there still needs to be more research evaluating the impact of the physicochemical properties of polymer nanofibers on the structure and function of cardiac cells. We have studied how poly(ϵ-caprolactone) and polyurethane nanofibrous mats with different physicochemical properties influence the viability, morphology, orientation, and maturation of cardiac cells. For this purpose, the cells taken from different species were used. They were rat ventricular cardiomyoblasts (H9c2), mouse atrial cardiomyocytes (CMs) (HL-1), and human ventricular CMs. Based on the results, it can be concluded that cardiac cells cultured on nanofibers exhibit greater maturity in terms of orientation, morphology, and gene expression levels compared to cells cultured on polystyrene plates. Additionally, the physicochemical properties of nanofibers affecting the functionality of cardiac cells from different species and different parts of the heart were evaluated. These studies can support research on understanding and explaining mechanisms leading to cellular maturity present in the heart and the selection of nanofibers that will effectively help the maturation of CMs.

Enhanced anti-corrosion and microwave absorption properties of novel binary titanium niobium nitrides nanofiber

Enhanced anti-corrosion and microwave absorption properties of novel binary titanium niobium nitrides nanofiber

Electrospun nanofibers as advanced wound dressing materials: comparative analysis of single-layered and multilayered nanofibers containing polycaprolactone, methylcellulose, and polyvinyl alcohol

The dressing materials that provide surface protection, bacteriostatic activities, and tissue regeneration are important for the treatment and management of complex wounds. This study aimed to evaluate the wound-healing properties of electrospun nanofibers containing a blend of methylcellulose (MC) and polyvinyl alcohol (PVA). The nanofibers were tested in single-layered (S-NFs) and multilayered (M-NFs) forms (PCL/MC-PVA/PCL). In vitro scratch assay using L929 cells and in vivo experiments on Wistar rats were conducted. The results showed that both S-NFs and M-NFs significantly accelerated wound closure by promoting cell migration. M-NFs demonstrated superior wound healing activity compared to S-NFs. Additionally, M-NFs exhibited faster skin epithelization compared to S-NFs. Histopathological evaluation confirmed the absence of irritation or lesions on the healed wound surface. Overall, the study concluded that these polymeric nanofibers have the potential to be used as self-wound healing dressings. They are safe, non-toxic, biodegradable, and biocompatible.

Unmasking the Electrochemiluminescence Properties of Ternary Mn/Fe/Co Metals Doped Porous g-C3N4 Fiber-like Nanostructure.

Graphitic-phase carbon nitride (g-C3N4) materials have exhibited increasingly remarkable performance as emerging electrochemiluminescence (ECL) emitters, owing to their unique optical and electronic properties; however, the ECL merits of porous g-C3N4 nanofibers doped with ternary metals are not yet explored. Deciphering the ECL properties of trimetal-doped g-C3N4 nanofibers could provide an exquisite pathway for ultrasensitive sensing and imaging with impressive advantages of minimal background signal, great sensitivity, and durability. Herein, we rationally synthesized g-C3N4 nanofibers doped atomically with Mn, Fe, and Co elements (Mn/Fe/Co/g-C3N4) in a one-pot via the protonation in ethanol and annealing process driven by the rolling up mechanism. The ECL performance of g-C3N4 with and without metal dopants was investigated and compared with standard Ru(bpy)32+ in the presence of potassium persulfate (K2S2O8) as the coreactant. Notably, g-C3N4 nanofibers doped with metal ions exhibited an ECL efficiency of 483% that was 4.83 times higher than that of Ru(bpy)32+. Mechanistic investigations unveiled that the g-C3N4 nanofibers possess a large surface area and, as a result, exhibit a reduced interfacial impedance within the porous microstructure. These factors contribute to the acceleration of charge transfer rates and the stabilization of charge carriers and excitons, ultimately facilitating the ECL process. This research endeavor may pave the way for a new hot research area and serves as a powerful tool for elucidating fundamental inquiries of ECL on one-dimensional g-C3N4 nanostructures.

The effect of solution viscosity on the quality of electroactive nanofibers produced by electrospinning

This work describes the modification of organic–inorganic nanofibrous templates for advanced electrotechnical applications and their filling with active particles from various materials, according to their intended use. The organic component of the templates consists of high molecular polyvinylpyrrolidone. The inorganic part is colloidal SiO2. The organic–inorganic templates produce by electrospinning can be filled with inorganic particles with diameter below 50 µm (for example, different types of spinels or electroactive nanopowders). The idea is to create a modifiable and flexible material for use as a template for electrodes or a solid electrolyte in a safe solid-state battery. The quality and properties of nanofibers are very important for advanced applications, and therefore, the optimization of the manufacturing process is needed. The most important property is the viscosity of the organic–inorganic solution for electrospinning. The influence of viscosity on the quality of nanofibrous layers was observed even with very subtle differences in viscosity. The age of the precursors and the resulting workability time also plays a significant role.Graphical abstract

An easy-to-clean nanofiber coating containing zanthoxylum bungeanum essential oil/β-cyclodextrin inclusion complex for the preservation of mangoes

This work aimed to investigat the properties of an antioxidant nanofiber coating incorporating zanthoxylum bungeanum essential oil and its function in the preservation of mangoes. Results showed that with the increase of zanthoxylum bungeanum essential oil-β-cyclodextrin inclusion complex (ZBEO-β-CD-IC) content in the nanofiber coating, the porosity, water vapor permeability, and oxygen permeability of the coating decreased, but the antioxidant activities increased. During storage, the increase of ZBEO-β-CD-IC content in the coating decreased weight loss and the respiration rate, and delayed the softening of tissue and yellowing of peel color. On the twelfth day, as the ZBEO-β-CD-IC content in the coating increased, the contents of flavonoids, total phenols, and ascorbic acid in mangoes increased from 2.36 × 10−2 to 2.87 × 10−2 g kg−1, 23.76 × 10−2 to 28.06 × 10−2 g kg−1, and 24.20 × 10−2 to 39.38 × 10−2 g kg−1, respectively. Hydrogen peroxide content, superoxide anion rate, and malondialdehyde content decreased from 4.62 to 2.98 mmol kg−1, 0.53 to 0.36 μmol min−1 kg−1, and 8.22 to 6.24 μmol kg−1, respectively. The activities of peroxidase, superoxide dismutase, catalase, ascorbate peroxidase were also inhibited after mangoes were coated in nanofibers containing ZBEO-β-CD-IC.

Humidity-responsive antimicrobial properties of EVOH nanofibers loaded with cuminaldehyde/HβCD inclusion complexes and its application in chicken preservation

The application of cuminaldehyde (CUM) in the food industry is limited by its low water solubility, stability and bioavailability. In this work, the inclusion complex (IC) of CUM and 2-hydroxypropyl-β-cyclodextrin (HβCD) was synthesized (CUM/HβCD-IC), and then ethylene vinyl alcohol copolymer (EVOH) containing CUM/HβCD-IC was prepared via coaxial electrospinning (CUM/HβCD-IC-EVOH-NF, CHIE-NF). The encapsulation efficiency and loading efficiency of CUM/HβCD-IC were 78.00% and 8.51%, respectively. The formation of solid CUM/HβCD-IC was confirmed by X-ray diffraction, Fourier transform infrared spectroscopy, Raman spectroscopy, thermogravimetric analysis and field emission scanning electron microscopy (FESEM). Also, the CUM could enter the hydrophobic cavity of HβCD and be stabilized by hydrogen bond between CUM and HβCD. Transmission electron microscopy verified the successful preparation of core-shell nanofiber, and FESEM showed that the average diameter of CHIE-NF was 444 ± 127 nm. In addition, CHIE-NF achieved controlled release of CUM through EVOH responsive to humidity, improved the thermostability of free CUM, increased mechanical strength, and exhibited antibacterial ability against Escherichia coli and Staphylococcus aureus. In the application for chicken meat preservation, CHIE-NF significantly slowed down the increase of total volatile basic nitrogen, pH value, total viable count, Enterobacteriaceae and lactic acid bacteria in minced chicken meat, and the shelf life of the meat increased by nearly 3 days compared to the control group based on the tested parameters. In summary, CHIE-NF has the potential for application in food field such as active packaging.

Electrospun nanofiber drug delivery systems and recent applications: An overview

Fiber technology plays a significant role in advancing drug research. While developing drug delivery systems, nanofiber technology has gained importance due to its high surface area to volume ratio and porosity. The most preferred nanofiber production method is the electrospinning method. This review focuses on electrospun nanofiber drug delivery systems, including analysis of critical process parameters affecting electrospinning and nanofiber properties. Moreover, the design strategies for nanofiber drug delivery systems are explored, including equipment preferences and design types. Given to these design strategies, it is possible to design either nanofiber mat or nanofiber itself. It has been shown that a tailor-made drug delivery system can be prepared using axial-based nozzles and other equipment options. In addition, the prominent features and usage areas of frequently used polymers are mentioned. General characterization studies of post-production nanofibers are discussed. Examples of areas of use for pharmaceutical purposes are presented. Finally, drug release kinetics were evaluated on electrospun nanofiber drug delivery systems. As a result of exhaustive evaluations, various effective applications in the literature have been shown to achieve remarkable results such as drug release manipulation, drug targeting, self-assembling formulation strategies. Therefore, it is clear that in the field of electrospun nanofiber technology, it is possible to modify all the process options and develop a unique drug delivery product, thanks to a comprehensive evaluation of the critical quality parameters of the drug product.

Investigating the Impact of Polyvinyl Alcohol Addition on the Thermal Behavior and Chemical Structure of Electrospun Cellulose Nanofibers

The study aimed to investigate the effect of adding polyvinyl alcohol (PVA) on the chemical and thermal properties of cellulose nanofibers (CNFs). The CNF was prepared using electrospinning with varying amounts of PVA, and the resulting samples were analyzed using Fourier-transform infrared (FTIR) spectroscopy and Thermogravimetric analysis (TGA). The FTIR results showed that adding PVA did not significantly affect the chemical structure of CNF but led to the appearance of new peaks attributed to the characteristic peaks of both CNF and PVA. Moreover, the TGA results revealed that all samples underwent weight degradation after being heated from 350°C. The addition and removal of PVA did not significantly alter the thermal behavior of the CNF. Overall, the results suggested that PVA can be used as a compatible additive to CNF without significant changes to their properties, which could have potential applications in various fields, including biodegradable packaging and drug delivery systems.

Optimized Cu-doping in ZnO electro-spun nanofibers for enhanced photovoltaic performance in perovskite solar cells and photocatalytic dye degradation.

Perovskite solar cells (PSCs) compete with conventional solar cells regarding their low-temperature processing and suitable power conversion efficiency. In PSCs, the electron transport layer (ETL) plays a vital role in charge extraction and avoiding recombination; however, poor charge transport of ETL leads to high internal resistance and associated low fill factors. To successfully resolve this challenge, copper-doped zinc oxide nanofibers as an electron transport layer are prepared with various doping levels of 1, 2, and 3 wt% using the electrospinning sol-gel method. The 3 wt% doping of Cu revealed the optimum performance as an ETL, as it offers an electrically efficient transporting structure. SEM images revealed a randomly oriented distribution of nanofibers with different sizes having mesoporous uniformity. Optical properties of doped nanofibers examined using UV-visible analysis showed an extended light absorption due to heteroatom-doping. Adding Cu into the ZnO leads to enhanced charge mobility across the electron transport material. According to Hall measurements, dopant concentration favors the conductivity and other features essentially required for charge extraction and transport. The solar cell efficiency of ZnO doped with 0%, 1%, 2%, and 3% Cu is 4.94%, 5.97%, 6.89%, and 9.79%, respectively. The antibacterial and photocatalytic activities of the prepared doped and undoped ZnO are also investigated. The better light absorption of Cu-ZnO showed a pronounced improvement in the photocatalytic activity of textile electrodes loaded with doped ZnO. The dye degradation rate reaches 95% in 180 min under visible light. In addition, these textile electrodes showed strong antibacterial activity due to the production of reactive oxygen species under light absorption.

Relationship between cyclic tensile properties of cellulose nanofiber reinforced natural rubber and volume fraction of bound rubber obtained from swelling tests

Relationship between cyclic tensile properties of cellulose nanofiber reinforced natural rubber and volume fraction of bound rubber obtained from swelling tests

Pore properties of carbon nanofibers fabricated using template method and alkali activation method

Pore properties of carbon nanofibers fabricated using template method and alkali activation method

Preparation Methods and Applications of Carbon Nanotubes and Carbon Nanotube Fibers

In recent years, carbon nanotubes have received widespread attention due to their unique structure and properties, making them applicable in various fields. This article discusses the excellent mechanical, optical, and electrical properties of carbon nanotubes and nanofibers. It then briefly introduces the preparation methods of carbon nanotubes and nanofibers, and finally summarizes the advantages and disadvantages of the preparation process. Research results indicate that the performance of carbon nanofibers is superior to that of carbon nanotubes. Due to their lightweight, flexibility, high conductivity and high surface area, carbon nanofibers play a significant role in the medical, chemical, and chip fields. However, the preparation process of carbon nanofibers is influenced by external environmental factors, resulting in poor performance and hindering research progress. This article aims to find a suitable preparation method to address the issue of poor performance of nanotubes and hopes to extensively apply carbon nanotubes and nanofibers in future developments.

A comparative investigation of the structure and properties of nanofibers based on Bombyx mori chitosan and Artemia sp.cysts chitosan

A comparative investigation of the structure and properties of nanofibers based on <i>Bombyx mori</i> chitosan and Artemia <i>sp.cysts</i> chitosan

Preparation and characterization of glutathione loaded polyvinyl alcohol electrospun nanofibers

Reduced glutathione, or L-glutathione, is a tripeptide protein that occurs naturally in almost all cells of the human body. It is an antioxidant and plays a significant role in neutralizing oxidative stress. Oxidative stress is responsible for promoting many diseases and abnormalities in the body. This antioxidant decreases with time, and resulting in a number of disorders. To overcome these issues, experts recommend taking glutathione supplements. This study was aimed to design glutathione-loaded polyvinyl alcohol nanofibers, considering the properties of nanofibers that could be used as glutathione supplements to improve the deficiency of glutathione in the human body. With the electrospinning technique, poly (vinyl alcohol) loaded glutathione nanofibers were designed. The prepared nanofibers were characterized using Scanning Electron Microscopy (SEM), Fourier Transform Infrared Spectroscopy (FTIR), X-ray diffraction (XRD), and Ultraviolet-Visible Spectroscopy (UV–Vis) techniques. The antioxidant activity of the nanofibers was also determined; the activity indicated the eradication of free radicals.

On-Demand Sequential Release of Dual Drug from pH-Responsive Electrospun Janus Nanofiber Membranes toward Wound Healing and Infection Control.

Drugs against bacteria and abnormal cells, such as antibiotics and anticancer drugs, may save human lives. However, drug resistance is becoming more common in the clinical world. Nowadays, a synergistic action of multiple bioactive compounds and their combination with smart nanoplatforms has been considered an alternative therapeutic strategy to fight drug resistance in multidrug-resistant cancers and microorganisms. The present study reports a one-step fabrication of innovative pH-responsive Janus nanofibers loaded with two active compounds, each in separate polymer compartments for synergistic combination therapy. By dissolving one of the compartments from the nanofibers, we could clearly demonstrate a highly yielded anisotropic Janus structure with two faces by scanning electron microscopy (SEM) analysis. To better understand the distinctive attributes of Janus nanofibers, several analytical methods, such as X-ray diffraction (XRD), FTIR spectroscopy, and contact angle goniometry, were utilized to examine and compare them to those of monolithic nanofibers. Furthermore, a drug release test was conducted in pH 7.4 and 6.0 media since the properties of Janus nanofibers correlate significantly with different environmental pH levels. This resulted in the on-demand sequential codelivery of octenidine (OCT) and curcumin (CUR) to the corresponding pH stimulus. Accordingly, the antibacterial properties of Janus fibers against Escherichia coli and Staphylococcus aureus, tested in a suspension test, were pH-dependent, i.e., greater in pH 6 due to the synergistic action of two active compounds, and Eudragit E100 (EE), and highly satisfactory. The biocompatibility of the Janus fibers was confirmed in selected tests.