Electrospun Cellulose Nanofibers Research Articles

Research upon Cu-Doping Contents in TiO2 Nanoparticles Incorporated onto Cellulose Nanofibers for Dye Removal and Self-Cleaning Applications.

Cu-doping contents in the TiO2 lattice structure were studied to show the effects on the crystal structure, morphology, and photocatalytic activity of TiO2 nanoparticles and thus composite cellulosic nanofibrous membranes. Pristine and copper-doped TiO2 nanoparticles were synthesized using the sol-gel technique, a wet chemical method with the advantages of low synthesizing temperature, uniform nanosize distribution, and purity. The as-synthesized semiconductor nanoparticles were first tested with the dye removal process and then impregnated onto electrospun cellulose nanofibers (CL nanofibers) to acquire modified nanofibers with self-cleaning properties. The as-prepared composite CL nanofibers consisting of doped and undoped TiO2 nanoparticles were characterized by various techniques, such as field emission scanning electron microscopy, transmission electron microscopy, UV-vis, X-ray diffraction, Fourier transform infrared spectroscopy, and tensile tests. The copper-doped TiO2 molar ratio in the nanocomposite was found to possess a pronounced impact on the dye removal and self-cleaning effects under the visible light spectrum, whereas TiO2 is highly effective under specific UV-light irradiation. Optical measurements and dye decomposition showed that the Cu-doped TiO2 nanocomposite was optimized at a 1% molar ratio by the copper-doping concentration regarding dye removal and self-cleaning applications under the visible light range.

Improved mRNA affinity chromatography binding capacity and throughput using an oligo-dT immobilized electrospun polymer nanofiber adsorbent

Increased demand for mRNA-based therapeutics and improved in vitro transcription (IVT) yields have challenged the mRNA purification platform. Hybridization-affinity chromatography with an immobilized oligo-deoxythymidilic acid (oligodT) ligand is often used to capture mRNA through base pairing with the polyadenylated tail. Commercially available oligodT matrices include perfusive cross-linked poly(styrene-divinylbenzene) 50 µm POROS™ chromatography resin beads and convective polymethacrylate CIMmultus® monolithic columns consisting of 2 µm interconnected channels. POROS™ columns may be limited by poor mass transfer for larger mRNAs and slow flowrates, while monoliths can operate at higher flowrates but are limited by modest binding capacity. To enable both high flowrates and binding capacity for mRNA of all lengths, prototype chromatography media was developed by Cytiva using oligodT immobilized electrospun cellulose nanofibers (Fibro™) with a 0.3–0.4 µm pore size. In this work, four polyadenylated mRNAs ranging from ∼1900–4300 nucleotides were used to compare the dynamic binding capacity (DBC) of Fibro™, POROS® and CIMmultus® columns as a function of residence time and binding buffer compositions. Fibro™ improved the DBC ∼2–4-fold higher than CIMmultus® and ∼2–13-fold higher than POROS™ across all residence times, mRNA length, and binding matrix compositions tested. CIMmultus® DBC was least dependent on residence time and mRNA size, while both Fibro™ and POROS™ DBC increased at slower flowrates and with shorter mRNA. Surprisingly, inverse size exclusion (ISE) experiments showed that POROS™ was not limited by diffusion and POROS™ along with CIMmultus® demonstrate higher mRNA permeation however the Fibro™ prototype is not in the final configuration. Lastly, IVT reaction products were subjected to purification and oligodT elution product yield, quality, and purity were consistent across the three matrices investigated. These results highlight the benefits of high DBC and equivalent product profiles offered by the oligodT Fibro™ prototype compared to commercially available oligodT media.

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.

Electrospun cellulose nanofibers immobilized with anthocyanin extract for colorimetric determination of bacteria

A novel smart biochromic textile sensor was developed by immobilizing anthocyanin extract into electrospun cellulose acetate nanofibers to detect bacteria for numerous potential uses, such as healthcare monitoring. Red-cabbage was employed to extract anthocyanin, which was then applied to cellulose acetate nanofibers treated with potassium aluminum sulfate as a mordant. Thus, nanoparticles (NPs) of mordant/anthocyanin (65–115 nm) were generated in situ on the surface of cellulose acetate nanofibrous film. The pH of a growing bacterial culture medium is known to change when bacteria multiply. The absorbance spectra revealed a bluish shift from 595 nm (purple) to 448 nm (green) during the growth of Gram-negative bacteria (E. coli) owing to the discharge of total volatile basic amines as secretion metabolites. On the other hand, the absorption spectra of a growing bacterial culture containing Gram-positive bacteria (L. acidophilus) showed a blue shift from 595 nm (purplish) to 478 nm (pink) as a result of releasing lactic acid as a secretion metabolite. Both absorbance spectra and CIE Lab parameters were used to determine the color shifts. Various analytical techniques were utilized to study the morphology of the anthocyanin-encapsulated electrospun cellulose nanofibers. The cytotoxic effects of the colored cellulose acetate nanofibers were tested.

Green Electrospun Nanofibers for Biomedicine and Biotechnology

Green electrospinning harnesses the potential of renewable biomaterials to craft biodegradable nanofiber structures, expanding their utility across a spectrum of applications. In this comprehensive review, we summarize the production, characterization and application of electrospun cellulose, collagen, gelatin and other biopolymer nanofibers in tissue engineering, drug delivery, biosensing, environmental remediation, agriculture and synthetic biology. These applications span diverse fields, including tissue engineering, drug delivery, biosensing, environmental remediation, agriculture, and synthetic biology. In the realm of tissue engineering, nanofibers emerge as key players, adept at mimicking the intricacies of the extracellular matrix. These fibers serve as scaffolds and vascular grafts, showcasing their potential to regenerate and repair tissues. Moreover, they facilitate controlled drug and gene delivery, ensuring sustained therapeutic levels essential for optimized wound healing and cancer treatment. Biosensing platforms, another prominent arena, leverage nanofibers by immobilizing enzymes and antibodies onto their surfaces. This enables precise glucose monitoring, pathogen detection, and immunodiagnostics. In the environmental sector, these fibers prove invaluable, purifying water through efficient adsorption and filtration, while also serving as potent air filtration agents against pollutants and pathogens. Agricultural applications see the deployment of nanofibers in controlled release fertilizers and pesticides, enhancing crop management, and extending antimicrobial food packaging coatings to prolong shelf life. In the realm of synthetic biology, these fibers play a pivotal role by encapsulating cells and facilitating bacteria-mediated prodrug activation strategies. Across this multifaceted landscape, nanofibers offer tunable topographies and surface functionalities that tightly regulate cellular behavior and molecular interactions. Importantly, their biodegradable nature aligns with sustainability goals, positioning them as promising alternatives to synthetic polymer-based technologies. As research and development continue to refine and expand the capabilities of green electrospun nanofibers, their versatility promises to advance numerous applications in the realms of biomedicine and biotechnology, contributing to a more sustainable and environmentally conscious future.

Electrospun Cellulose Nanofiber Membranes as Multifunctional Separators for High Energy and Stable Lithium-Sulfur Batteries

Although Li–S batteries (LSB) are one of the most promising electrochemical energy storage technologies, their practical applications are limited by their rapid capacity decay and uncontrolled lithium dendrite formation. In addition to the well-known role of a separator in lithium-ion batteries, LSB separators must perform additional functions. Using a facile electrospinning method, we developed an eco-friendly separator prepared from natural cellulose with an interconnected fibrous and porous structure rich in polar oxygen-containing functional groups. These polar functional groups enhance electrolyte wettability, polysulfide adsorption, and lithiophilicity, thus boosting LSB performance. A cellulose separator with a thickness (22 μm) comparable to that of a commercial polypropylene (Celgard) separator delivers an initial discharge capacity of 1458 mAh·g−1 at 0.1C with a high sulfur utilization of 87%, including a high reversible discharge capacity of 1091 mAh·g−1 for 100 cycles, exhibiting a 1.8-times greater capacity retention than those of Celgard-containing LSBs. In addition, an excellent rate capability of 908 mAh·g−1 can be achieved at a high rate of 1C. These intriguing characteristics indicate that these separators could replace conventional synthetic polymer-based separators for commercial LSBs.

The Effect of Alkali Treatment on the Cellulose Extracted from Rice Husk as Potential Resources of Biomass

Over the last few decades, the use of agro by-products as a biopolymer for various applications has attracted significant interest of researchers. Rice husk (RH) is one of the agro by-products produced abundantly worldwide and a great deal of studies in extracting and utilizing silica from RH have been reported but scarcely for its cellulose components. A specific study on the utilization of cellulose extracted from RH for the electrospinning process also remains unreported. Chemical pre-treatment seems to be the most crucial step which improves the elimination of the cementing components and exposing the cellulose for further applications. This study aimed to explore the potential of RH as a source of raw material to produce cellulose nanofiber. The cellulose was extracted by acid pre-treatment, alkaline treatment at varying sodium hydroxide (NaOH) concentrations, followed by bleaching treatment with sodium hypochlorite for complete removal of the amorphous region. The resulting cellulose was characterized and the main properties (morphology and sizes) of the extracted cellulose were made using scanning electron microscopy (SEM). The findings revealed the almost complete removal of the noncellulosic components for the subsequent production of electrospun cellulose nanofibers. Therefore, the output of the cellulose from this underutilized agro-waste has commercial application potential that can add value and be further utilized for the electrospinning process.

The Fabrication of Cesium Lead Bromide-Coated Cellulose Nanocomposites and Their Effect on the Detection of Nitrogen Gas.

In this work, we fabricate cesium lead bromide nanofibers (CsPbBr3 NFs) via the attachment of cesium lead bromide nanocrystals (CsPbBr3 NCs) on the surface of electrospun cellulose nanofibers (CNFs) and employ them in a sensor to effectively detect gaseous nitrogen. The CsPbBr3 NFs are produced initially by producing CsPbBr3 NCs through hot injection and dispersing on hexane, followed by dipping CNFs and ultrasonicate for 1 h. Morphological characterization through visual, SEM and TEM image, and crystalline structure analysis by XRD and FT-IR analysis of CsPbBr3 NFs and NCs show similar spectra except for PL due to unavoidable damage during the ultrasonication. Gaseous nitrogen is subsequently detected using the photoluminescence (PL) property of CsPbBr3 NFs, in which the PL intensity dramatically decreases under various flow rate. Therefore, we believe that the proposed CsPbBr3 NFs show significant promise for use in detection sensors in various industrial field and decrease the potential of fatal damage to workers due to suffocation.

Polyethylenimine-Functionalized Nanofiber Nonwovens Electrospun from Cotton Cellulose for Wound Dressing with High Drug Loading and Sustained Release Properties.

Electrospun cellulose nanofiber nonwovens have shown promise in wound dressing owing to the highly interconnected pore structure, high hydrophilicity coupled with other coveted characteristics of biodegradability, biocompatibility and renewability. However, electrospun cellulose wound dressings with loaded drugs for better wound healing have been rarely reported. In this study, a novel wound dressing with a high drug loading capacity and sustained drug release properties was successfully fabricated via electropinning of cellulose followed by polyethylenimine (PEI)-functionalization. Remarkably, the grafted PEI chains on the surface of electrospun cellulose nanofibers provided numerous active amino groups, while the highly porous structure of nonwovens could be well retained after modification, which resulted in enhanced adsorption performance against the anionic drug of sodium salicylate (NaSA). More specifically, when immersed in 100 mg/L NaSA solution for 24 h, the as-prepared cellulose-PEI nonwoven displayed a multilayer adsorption behavior. And at the optimal pH of 3, a high drug loading capacity of 78 mg/g could be achieved, which was 20 times higher than that of pristine electrospun cellulose nonwoven. Furthermore, it was discovered that the NaSA-loaded cellulose-PEI could continuously release the drug for 12 h in simulated body fluid (SBF), indicating the versatility of cellulose-PEI as an advanced wound dressing with drug carrier functionalities.

Coating of Au@Ag on electrospun cellulose nanofibers for wound healing and antibacterial activity

Coating of Au@Ag on electrospun cellulose nanofibers for wound healing and antibacterial activity

Reactive Dyeing of Electrospun Cellulose Nanofibers by Pad-steam Method

Reactive Dyeing of Electrospun Cellulose Nanofibers by Pad-steam Method

Construction of ZIF@electrospun cellulose nanofiber derived N doped metallic cobalt embedded carbon nanofiber composite as binder-free supercapacitance electrode

In this study, binder-free hybrid supercapacitance electrode based on N, Co co-doped porous carbon polyhedral encapsulated carbon nanofibers composites (N-Co/CNF) was prepared through pyrolyzing cobalt based zeolitic imidazolate frameworks (ZIF-67(Co)) incorporated electrospun cellulose nanofibers. With rational combination of the conductivity provided by cellulose derived CNF, promising porosity provided by CNF and ZIF-67(Co) derived porous carbon and uniformly dispersed metallic cobalt nanoparticles, the N-Co/CNF displayed excellent electrochemical properties. Specifically, the N-Co/CNF pyrolyzed at 800 °C possessed superior electrochemical performance in 1 M H2SO4 electrolyte, including a specific capacitance of ~433 F/g and 84% of the capacitance retention after 3000 consecutive charge-discharge cycles. This significantly exceeded the performance of cellulose derived CNF based pure carbonaceous electrode. Therefore, the present study provides a new view on the construction of high performance hybrid supercapacitance electrode which introduces renewable biomass resources like cellulose as both carbonaceous material precursors and conductive binders.

Lignin-mediated in-situ synthesis of CuO nanoparticles on cellulose nanofibers: A potential wound dressing material

Herein we present our research on the synthesis of CuO nanoparticles on the surface of electrospun cellulose (CE) nanofibers using alkali lignin as a reducing agent. Fascinatingly, CA nanofibers were deacetalized during alkali lignin treatment, which was verified by FTIR-ATR spectra. The morphology of the produced nanofibers was observed with SEM and TEM. The presence of CuO nanoparticles was verified by EDX, XRD, and XPS. The Cu/CE nanofibers showed low thermal stability. MVTR values of 2100–1900 g/m2/day are adequate for the transport of air and moisture from the wound surface. The Cu/CE showed faster release (80%) of copper ions to aqueous environment within 24 h and seemed to advance towards plateau for the next five days. The Cu/CE nanofibrous mats exhibited excellent antibacterial efficacy against both gram-negative Escherichia coli (E. coli) and gram-positive Staphylococcus aureus (S. aureus) bacteria. NIH3T3 fibroblast cells have excellent migrating and proliferating ability on our prepared nanofibrous mats. The presence of bound alkali lignin on the surface of nanofibers added a benefit of antioxidant activity. These findings revealed that such type of nanofibrous mats could be used as a potential wound dressing material.

Effects of surface condition of conductive electrospun nanofiber mats on cell behavior for nerve tissue engineering

Electrospun nanofibrous scaffold is a promising implant for peripheral nerve regeneration. Herein, to investigate the effect of surface morphological features and electrical properties of scaffolds on nerve cell behavior, we modified electrospun cellulose (EC) fibrous mats with four kind of soluble conductive polymers derivates (poly (N-(methacryl ethyl) pyrrole) (PMAEPy), poly (N-(2-hydroxyethyl) pyrrole) (PHEPy), poly (3-(Ethoxycarbonyl) thiophene) (P3ECT) and poly (3-thiophenethanol) (P3TE)) by an in-situ polymerization method. The morphological characterization showed that conductive polymers formed aggregated nanoparticles and coatings on the EC nanofibers with the increased fiber diameter further affected the surface properties. Compared with pure EC scaffold, more PC12 cells were adhered and grown on modified mats, with more integral and clearer cell morphology. The results of protein adsorption study indicated that modified EC mats could provide more protein adsorption site due to their characteristic surface morphology, which is beneficial to cell adhesion and growth. The results in this study suggested that these conductive polymers modified scaffolds with special surface morphology have potential applications in neural tissue engineering.

Environmentally friendly superabsorbent fibers based on electrospun cellulose nanofibers extracted from wheat straw

Superabsorbent polymers currently used in health and agricultural sectors are based on petroleum-based materials which led to serious concerns in the society. Here, superabsorbent fibers (SAFs) based on electrospun cellulose nanofibers (ECNFs) were prepared. Firstly, cellulose was removed from wheat straw, pre-treated with the TEMPO-mediated oxidation and subsequently dissolved into Trifluoroacetic acid for production of ECNFs through the electrospinning approach. The maximum swelling ratios of 225 g/g and 208 g/g in distilled water and 0.9 wt% NaCl solution were measured for ESAFs composed of oxidized ECNFs containing 15 % poly (sodium acrylate), respectively. The ESAFs were characterized using Fourier transform infrared spectroscopy and field emission scanning electron microscopy analysis. The FESEM showed that ESAFs formed high strength three-dimensional architecture networks. Also, the results showed that the ionic sensitivity of this ECNFs were low. The prepared ESAFs are attractive renewable alternatives for different applications, contributing to a reduction of plastic microspheres.

Cellulose nanofibers electrospun from aqueous conditions

Electrospun cellulose nanofibers are promising biomaterials but are suffering from the use of unfavorable organic solvents during the electrospinning process. In this manuscript, we used the periodate oxidation—adipic acid dihydrazide crosslinking strategy to fabricate electrospun cellulose nanofibers. Periodate oxidation of cellulose generated water soluble aldehyde cellulose, which thus allowed for the electrospinning in aqueous solution and avoided the use of unfavorable organic solvents. The following crosslinking with adipic acid dihydrazide made the nanofibers water resistant. The results show that the prepared cellulose nanofiber mats show moderate wet mechanical strength around 1 MPa, are able to absorb water equal to 30 times of their own weight, can degrade gradually by hydrolysis, and are cytocompatible. These cellulose nanofibers are expected to find applications in biomedical fields such as wound healing and tissue regeneration.

Fabrications of cellulose nanocomposite for tailor-made applications

The unique properties of nanocelluloses (NCs), including nanodimension, renewability, low toxicity, biocompatibility, biodegradability, easy availability, and low cost, render them the ideal nanomaterials for diverse applications. Composite material consists of matrix material with low volume fraction and self-assembled NC fibers with a high volume fraction of reinforcing domain. These two-phase components are often combined to promote stiffness and improve toughness (by dissipating materials fracture energy). The challenge, however, is to control the alignment and distribution of NC within the matrix. Recent research has been focusing on the production of composites using different methodologies such as electrospun cellulose nanofibers, polymer-grafted NC, nanoparticle binding on NCs, assembly of NCs at the air/water and oil/water interfaces, protein-mediated interactions on NCs, and atomic layer deposition on NCs. In this case, NC serves as an appropriate candidate for composites preparation in comparison to the non-biodegradable nanofillers (e.g. carbon nanoclay and nanotube).

Nanocellulose and Polycaprolactone Nanospun Composite Membranes and Their Potential for the Removal of Pollutants from Water.

A composite membrane based on polycaprolactone (PCL) and cellulose nanofibers (CNF) with different compositions was prepared using the electro-spinning method, with the objective of developing organic membranes with good mechanical properties to remove contaminants from water. Water is a resource of primary importance for life and human activities. In this sense, cellulose obtained from agave bagasse and polycaprolactone nanofibers was used to prepare membranes that were tested by filtering tap water. The membranes obtained presented a porosity and structure on a nanometric scale. The water quality variables evaluated after filtration with the PCL/CNF membranes showed 100% turbidity removal, 100% conductivity, and heavy metal removal of the order of 75% to 99% for iron and chromium. CNF comprises biowaste derived from tequila production, and it has added value. Electro-spun CNF and PCL membranes can be applied as a “green” and eco-friendly filtration system for water purification.

Mechanical properties of poly(ε‐caprolactone) composites with electrospun cellulose nanofibers surface modified by 3‐aminopropyltriethoxysilane

ABSTRACTTo enhance the reinforcement effects of regenerated cellulose nanofibers (RC‐NF) in poly(ε‐caprolactone) (PCL), we synthesized RC‐NF‐3‐aminopropyltriethoxysilane (APS), the surface‐modified RC‐NF by APS. The RC‐NF were fabricated by the saponification of electrospun cellulose–acetate nanofibers. The surface modification by APS was confirmed by the X‐ray photoelectron spectroscopy (XPS). To enhance the mechanical property of PCL, the RC‐NF and the RC‐NF‐APS were separately compounded into PCL by compression molding. It was found that, when the fiber concentration of RC‐NF‐APS was 17 wt %, the Young's modulus at room temperature increased from 698.0 to 744.7 MPa, whereas the storage modulus at 55 °C almost increased from 180 to 220 MPa. The micrographs of the fracture surface of the composites revealed that the surface modification prevented the pull‐out of RC‐NF from PCL. It was concluded that the mechanical properties of the composites were enhanced due to the improvement of the compatibility between RC‐NF and PCL by the surface modification with APS. © 2019 Wiley Periodicals, Inc. J. Appl. Polym. Sci. 2020, 137, 48599.

Electrospun cellulose nanofibers for superhydrophobic and oleophobic membranes

In this study, we produced a super hydrophobic and oleophobic cellulose nanofiber membrane by reducing the surface energy of the membrane through the attachment of SiNPs and chemical vapor deposition of fluoroalkylsilane. SiNPs were growing on top of the fibers by using in situ sol-gel approach. SiNPs cellulose nanofiber composed mat was coated with fluoroalkylsilane by CVD. The grafted SiNPs on cellulose nanofiber were then coated with fluoroalkylsilane to lower the surface energy of the nanofiber membrane. The fabricated membrane showed excellent hydrophobicity and oleophobicity (also known as omniphobic), as demonstrated by its wetting resistance to water, ethanol, surfactant, and mineral oil. The prepared omniphobic membrane was used in direct contact membrane distillation (DCMD) to separate water from saline feed solutions containing low surface tension substances. The fabricated omniphobic cellulose nanofiber membrane showed very high resistance against wetting and it exhibited a stable water vapor flux performance for 10 h of operation. Moreover, the performance of the fabricated omniphobic cellulose nanofiber membrane was compared to commercial hydrophobic PVDF and PTFE membranes against saline feed solutions containing low surface tension substances.