Search Results (1,159)

To solve the limitations of these models for submicron materials like electrospun nanofiber membranes, a numerical simulation was used to construct a three-dimensional model closer to the actual structure to explore the filtration resistance and efficiency of these membranes. Based on the actual polydisperse electrospun nanofiber filter, the three-dimensional structure (fiber diameter 280 nm–1300 nm, thickness 0.0150 mm–0.0240 mm, and solid volume fraction 11.3–17.7%) was reconstructed by GeoDict software. The filtration resistance was simulated with the FlowDict module (surface velocity 6.89 cm/s, 20 °C), and the filtration efficiency was calculated with the FilterDict module (2.5 μm particles, tracking 20,000). The results are compared with the experimental values, Davids empirical formula, Happel model, and Kuwabara model. The results show that the simulated values of filtration resistance are generally higher than the experimental values (deviation ≤ 20%), among which the simulation and experiment have the highest consistency, followed by the Davids formula (such as the relative error of 41.62% at 9% spinning solution concentration), and the Kuwabara model has the largest error (59.86%). The simulated value of filtration efficiency is higher than the experimental value (deviation ≤ 7%), because the model assumes that the particles adhere directly after contacting the fiber, and the actual sliding off is not considered. This study confirms that numerical simulation can efficiently predict the filtration performance of electrospun nanofiber membranes. Therefore, it provides a basis for optimizing material structure by adjusting spinning parameters and promoting the engineering application of submicron filter materials. Full article

Thermoplastic polyurethane (TPU) electrospun fiber membranes possess unique micro-nano structures and excellent properties. Adjusting their wettability enables the directional transportation of lubricants. A conventional method for adjusting porosity and wettability involves inducing membrane shrinkage using absolute ethanol and heat treatment. However, the shrinkage response and the corresponding changes in the tensile properties of TPU fiber membranes after induction remain unclear, limiting their applications. Thus, in this study, after being peeled off, the samples were first left to stand at room temperature (RT) for 24 h to release residual stress and stabilize their dimensions, and then treated with dehydrated ethanol at RT and high temperature, respectively, with their shrinkage behaviors observed and recorded. The results showed that TPU nanofiber membranes shrank significantly in absolute ethanol, and the degree of shrinkage was temperature-dependent. The shrinkage rates were 2% and 4% in dehydrated ethanol at room temperature and high temperature, respectively, and heating increased the shrinkage effect by 200%. These findings prove that absolute ethanol causes TPU fibers to shrink, and high temperatures further promote shrinkage. However, although the strong synergistic effect of heat and solvent accelerates shrinkage, it may induce internal structural defects, resulting in the deterioration of mechanical properties. The contraction response induced by anhydrous ethanol stimulation can be used to directionally adjust the local density and modulus of TPU nanofiber membranes, thereby changing the wettability. This approach provides new opportunities for applications in areas such as medium transportation and interface friction reduction in lubrication systems. Full article

This research focuses on designing polymer membranes as biocompatible materials using home-built electrospinning equipment, offering alternative solutions for tissue regeneration applications. This technological development supports cell growth on biomaterial substrates, including hepatocellular carcinoma (Hep-G2) cells. This work researches the compatibility of polymer membranes (fiber mats) made of polyvinylidene difluoride (PVDF) for possible use in cellular engineering. A standard culture medium was employed to support the proliferation of Hep-G2 cells under controlled conditions (37 °C, 4.8% CO₂, and 100% relative humidity). Subsequently, after the incubation period, electrochemical impedance spectroscopy (EIS) assays were conducted in a physiological environment to characterize the electrical cellular response, providing insights into the biocompatibility of the material. Scanning electron microscopy (SEM) was employed to evaluate cell adhesion, morphology, and growth on the PVDF polymer membranes. The results suggest that PVDF polymer membranes can be successfully produced through electrospinning technology, resulting in the formation of a dipole structure, including the possible presence of a polar β-phase, contributing to piezoelectric activity. EIS measurements, based on R_ct and C_dl values, are indicators of ion charge transfer and strong electrical interactions at the membrane interface. These findings suggest a favorable environment for cell proliferation, thereby enhancing cellular interactions at the fiber interface within the electrolyte. SEM observations displayed a consistent distribution of fibers with a distinctive spherical agglomeration on the entire PVDF surface. Finally, integrating piezoelectric properties into cell culture systems provides new opportunities for investigating the influence of electrical interactions on cellular behavior through electrochemical techniques. Based on the experimental results, this electrospun polymer demonstrates great potential as a promising candidate for next-generation biomaterials, with a probable application in tissue regeneration. Full article

Moringa oleifera (MO), a nutritionally and pharmacologically potent species, is emerging as a sustainable candidate for applications across bioenergy, agriculture, textiles, pharmaceuticals, and biomedicine. This review explores recent advances in MO-based biotechnologies, highlighting novel extraction methods, green nanotechnology, and clinical trial findings. Although MO’s resilience offers promise for climate-smart agriculture and public health, challenges remain in standardizing cultivation and verifying therapeutic claims. This work underscores MO’s translational potential and the need for integrative, interdisciplinary research. MO is used in advanced materials, like electrospun fibers and biopolymers, showing filtration, antibacterial, anti-inflammatory, and antioxidant properties—important for the biomedical industry and environmental remediation. In textiles, it serves as an eco-friendly alternative for wastewater treatment and yarn sizing. Biotechnological advancements, such as genome sequencing and in vitro culture, enhance traits and metabolite production. MO supports green biotechnology through sustainable agriculture, nanomaterials, and biocomposites. MO shows potential for disease management, immune support, metabolic health, and dental care, but requires further clinical trials for validation. Its resilience is suitable for land restoration and food security in arid areas. AI and deep learning enhance Moringa breeding, allowing for faster, cost-effective development of improved varieties. MO’s diverse applications establish it as a key element for sustainable development in arid regions. Full article

In this work, the electrospinning technique was used to prepare novel polymeric composite fibers containing Te-doped bioactive glass powders. Bioactive glass powders containing tellurium (STe5 glass) were chosen as fillers for the composites, owing to their bioactive, antibacterial, and antioxidant properties. The biopolymer poly (ϵ-caprolactone) (PCL) and acetic acid (AA) were used as raw materials for the preparation of the polymeric matrix. FESEM analysis confirmed a good incorporation of the glass powders in the polymeric fibers, of up to 20% by weight. Wettability, mechanical, in vitro stability and preliminary antibacterial tests were also performed. The results showed that the treatment in AA did not affect the bioactivity of the glass powders, the presence of STe5 powders in PCL enhanced the wettability of the fibers, and mechanical properties improved by increasing the amount of STe5 powders, as well as the antibacterial effect. Therefore, the obtained materials appear promising for developing multifunctional composite materials for applications in tissue engineering. Full article

In this study, we present a flexible piezoelectric nanogenerator based on a zinc oxide (ZnO)/polyvinylidene fluoride (PVDF) nanocomposite electrospun onto a hemisphere-patterned PDMS substrate. The nanogenerator was fabricated by replicating a silicon mold with inverted hemispheres into PDMS, followed by direct electrospinning of ZnO-dispersed PVDF nanofibers. Varying the ZnO concentration from 0.6 to 1.4 wt% allowed us to evaluate its effect on structural, dielectric, and piezoelectric properties. The nanogenerator containing 0.8 wt% ZnO exhibited the thinnest fibers (371 nm), the highest β-phase fraction (85.6%), and the highest dielectric constant (35.8). As a result, it achieved the maximum output voltage of 7.30 V, with excellent signal consistency under an applied pressure of 5 N. Comparisons with pristine PVDF- and ZnO/PVDF-only devices demonstrated the synergistic effect of ZnO loading and patterned PDMS on the enhancement of piezoelectric output. The hemisphere-patterned PDMS substrate improved the mechanical strain distribution, interfacial contact, and charge collection efficiency. These results highlight the potential of ZnO/PVDF/PDMS hybrid nanogenerators for use in wearable electronics and self-powered sensor systems. Full article

Wound dressings prevent complications such as infections and potentially severe outcomes, including death, if wounds are left untreated. Wound dressings have evolved from rudimentary coverings made from natural materials to sophisticated, functionalized dressings designed to enhance wound healing and support tissue repair more effectively. These materials are often referred to as scaffolds in the literature, with wound dressing scaffolds intended to interact with native skin tissue and support tissue regeneration, whereas conventional wound dressings are designed primarily to protect the wound without directly interacting with the underlying tissue. However, there is a functional overlap between these categories, and the boundary is often blurred due to the increasing multifunctionality of modern wound dressings. This review will focus on developing wound dressings (scaffolds or not) based on fibers, their properties, and applications. Advances in nanomedicine have highlighted significant improvements in wound care by applying electrospun nanofibers that mimic the natural extracellular matrix. Therefore, this review explores recent advances in wound healing physiology, highlights nanofiber-based wound dressing materials developed through electrospinning, and distinguishes conventional dressings from multifunctional wound dressing scaffolds. Full article

A ceramic–metal composite was synthesized using sol–gel and electrospinning methods to serve as a SERS substrate. The precursors used were tetraethyl orthosilicate, aluminum nitrate, and zirconium, and polyvinylpyrrolidone was added to electrospun nonwoven fibrous membranes. The membranes were sintered, decorated with silver nanoparticles. The enhancement substrates were made of fibers of cylindric morphology with an average diameter of approximately 190 nm, a smooth surface, and 9 nm spherical particles decorating the surface of the fibers. The enhancement capacity of the substrates was tested using pyridine, methyl orange, methylene blue, crystal violet, and Eriochrome black T at different concentrations with Raman spectroscopy to determine whether the size and complexity of the analyte has an impact on the enhancement capacity. Enhancement factors of 2.53 × 10², 3.06 × 10¹, 2.97 × 10³, 4.66 × 10³, and 1.45 × 10³ times were obtained for the signal of pyridine, methyl orange, methylene blue, crystal violet, and Eriochrome black T at concentrations of 1 nM. Full article

Electrospinning has emerged as a highly effective technique for fabricating micro- and nanofibers, which are characterized by high porosity, large surface area, and structural mimicry of the extracellular matrix (ECM). These properties render it particularly suitable for biomedical applications. This review provides a comprehensive overview of recent developments in electrospinning-based strategies across various biomedical fields, including tissue engineering, drug delivery, wound healing, enzyme immobilization, biosensing, and protective materials. The distinctive advantages of electrospun fibers—such as excellent biocompatibility, tunable architecture, and facile surface functionalization—are discussed, alongside challenges such as the toxicity of organic solvents and limitations in scalability. Emerging approaches, including environmentally benign electrospinning techniques and integration with advanced technologies such as 3D printing and microfluidics, present promising solutions for intelligent and personalized biomedical applications. Full article

Background/Objectives: The work presented herein focused on the development and characterization of a transdermal caffeine platform fabricated from ultrathin micro- and submicron fibers produced via electrospinning. Methods: The formulations incorporated caffeine encapsulated in a polyethylene oxide (PEO) matrix, combined with various permeation enhancers. A backing layer made of annealed electrospun polycaprolactone (PCL) facilitated the lamination of the two layers to form the final multilayer patch. Comprehensive characterization was conducted, utilizing scanning electron microscopy (SEM) to assess the fiber morphology, attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) for chemical detection and to assess the stability of the caffeine, and differential scanning calorimetry (DSC) along with wide-angle X-ray scattering (WAXS) to analyze the physical state of the caffeine within the fibers of the active layer. Additionally, Franz cell permeation studies were performed using both synthetic membranes (Strat-M) and ex vivo human stratum corneum (SC) to evaluate and model the permeation kinetics. Results: These experiments demonstrated the significant role of enhancers in modulating the caffeine permeation rates provided by the patch, achieving permeation rates of up to 0.73 mg/cm² within 24 h. Conclusions: This work highlights the potential of using electro-hydrodynamic processing technology to develop innovative transdermal delivery systems for drugs, offering a promising strategy for enhancing efficacy and innovative therapeutic direct plasma administration. Full article

The growing accumulation of plastic packaging waste poses severe environmental and health challenges. To address these issues, significant research has been devoted to developing biodegradable films; however, their weak mechanical and barrier properties limit their practical utility. This study introduces an innovative multilayer film production method, combining electrospun polycaprolactone (PCL) fibers with a chitosan matrix. Two configurations were investigated: (1) nonwoven PCL layers placed between chitosan sheets and (2) a chitosan sheet sandwiched between two nonwoven PCL layers. Both systems were evaluated using PCL fibers derived from medical-grade and technical-grade polymers. The chitosan/polycaprolactone/chitosan (CH/PCL/CH) configuration demonstrated superior performance, achieving enhanced interlayer cohesion and significantly improved mechanical strength, durability, and barrier properties. Notably, this configuration achieved tensile strength and elongation at break values of 57.1 MPa and 36.3%, respectively—more than double those of pure chitosan films. This breakthrough underscores the potential of multilayered biopolymer films as eco-friendly packaging solutions, offering exceptional promise for sustainable applications in the food packaging industry. Full article

Nanomaterials have emerged as a transformative technology in agricultural science, offering innovative solutions to improve plant–microbe interactions and crop productivity. The unique properties, such as high surface area, tunability, and reactivity, of nanomaterials, including nanoparticles, carbon-based materials, and electrospun fibers, render them ideal for applications such as nutrient delivery systems, microbial inoculants, and environmental monitoring. This review explores various types of nanomaterials employed in agriculture, focusing on their role in enhancing microbial colonization and soil health and optimizing plant growth. Key nanofabrication techniques, including top-down and bottom-up manufacturing, electrospinning, and nanoparticle synthesis, are discussed in relation to controlled release systems and microbial inoculants. Additionally, the influence of surface properties such as charge, porosity, and hydrophobicity on microbial adhesion and colonization is examined. Moreover, the potential of nanocoatings and electrospun fibers to enhance seed protection and promote beneficial microbial interactions is investigated. Furthermore, the integration of nanosensors for detecting pH, reactive oxygen species, and metabolites offers real-time insights into the biochemical dynamics of plant–microbe systems, applicable to precision farming. Finally, the environmental and safety considerations regarding the use of nanomaterials, including biodegradability, nanotoxicity, and regulatory concerns, are addressed. This review emphasizes the potential of nanomaterials to revolutionize sustainable agricultural practices by improving crop health, nutrient efficiency, and environmental resilience. Full article

This study presents the development and characterization of electrospun nanofibers composed of polyvinyl alcohol (PVA) and natural beeswax (BW). A stable emulsion containing 9 wt% PVA and 5 wt% BW was successfully formulated and electrospun. The effects of beeswax incorporation on solution properties-viscosity, conductivity, and surface tension—were systematically evaluated. Electrospinning was performed at 30 kV and a working distance of 14.5 cm, yielding nanofibers with diameters between 125 and 425 nm. Scanning electron microscopy (SEM) revealed increased surface roughness and diameter variability in PVA/BW fibers compared to the PVA. Fourier transform infrared spectroscopy (FTIR) confirmed physical incorporation of BW without evidence of chemical bonding. Thermogravimetric and differential scanning calorimetry analyses (TGA/DSC) demonstrated altered behavior and an expanded profile of temperature transitions due to the waxy components. The solubility test of the nanofiber mat in saline indicated that BW slows dissolution and improves the structural integrity of the fibers. This study demonstrates, for the first time, the incorporation of beeswax into electrospun PVA nanofibers with improved structural and thermal properties, indicating potential for further exploration in biomedical material design. Full article

Electrospun fibers, possessing biomimetic characteristics similar to fibrous extracellular matrices, have attracted widespread attention as scaffold materials for skin tissue engineering. The topographical structure of electrospun fibers plays a critical role in determining cell behavior. However, the effects of fiber topography on human skin fibroblasts (HSFs) remain unclear. In this study, electrospinning technology was employed to investigate how parallel and crossed fiber architectures influence the spreading morphology, proliferation, and migration of HSFs. The results demonstrated that cells exhibited spindle-shaped elongation along single fibers; on closely spaced parallel fibers, cells formed cross-adhesions between adjacent fibers, with a fiber spacing of 30–60 μm serving as the threshold range for distinguishing individual cell behaviors. At fiber intersections, a characteristic spacing of 100 μm distinguished three distinct cellular responses: anchoring, turning, and bridging. The probability of a cell altering its preexisting migration path depended on its ability to extend laterally and reach adjacent fibers, which was constrained by the upper limit of the cell body’s minor axis. This study elucidated the unique role of the electrospun fiber topography in guiding cellular decision-making in complex microenvironments, provided important insights into topography-triggered cell migration, and highlighted the practical significance of material-guided strategies in tissue engineering. Full article

Ultrafine fibers from poly(3-hydroxybutyrate) (PHB) and polyvinylpyrrolidone (PVP) and their blends with different component ratios in the range of 0/100 to 100/0 wt.% were obtained, and their structure and dynamic properties were studied. The polymers were obtained via electrospinning in solution mode. The structure, morphology, and segmental dynamic behavior of the fibers were determined using optical microscopy, SEM, EPR, DSC, and IR spectroscopy. The low-temperature maximum on the DSC endotherms provided information on the state of the PVP hydrogen bond network, which made it possible to determine the enthalpies of thermal destruction of these bonds. The PHB/PVP fiber blend ratio significantly affected the structural and dynamic parameters of the system. Thus, at low concentrations of PVP (up to 9%) in the structure of ultra-fine fibers, the distribution of this polymer occurs in the form of tiny particles, which are crystallization centers, which causes a significant increase in the degree of crystallinity (χ) activation energy (E_act) and slowing down of molecular dynamics (τ). At higher concentrations of PVP, loose interphase layers were formed in the system, which caused a decrease in these parameters. The strongest changes in the concentration of hydrogen bonds occurred when PVP was added to the composition from 17 to 50%, which was due to the formation of intermolecular hydrogen bonds both in PVP and during the interaction of PVP and PHB. The diffusion coefficient of water vapor in the studied systems (D) decreased as the concentration of glassy PVP in the composition increased. The concentration of the radical decreased with an increase in the proportion of PVP, which can be explained by the glassy state of this polymer at room temperature. A characteristic point of the 50/50% mixture component ratio was found in the region where an inversion transition of PHB from a dispersion material to a dispersed medium was assumed. The conducted studies made it possible for the first time to conduct a comprehensive analysis of the effect of the component ratio on the structural and dynamic characteristics of the PHB/PVP fibrous material at the molecular scale. Full article