Electrospun Nanofibers Research Articles

Development of polyvinyl alcohol nanofiber scaffolds loaded with flaxseed extract for bone regeneration: phytochemicals, cell proliferation, adhesion, and osteogenic gene expression.

Introduction: Bone tissue engineering seeks innovative materials that support cell growth and regeneration. Electrospun nanofibers, with their high surface area and tunable properties, serve as promising scaffolds. This study explores the incorporation of flaxseed extract, rich in polyphenolic compounds, into polyvinyl alcohol (PVA) nanofibers to improve their application in bone tissue engineering. Methods: High-performance liquid chromatography (HPLC) identified ten key compounds in flaxseed extract, including polyphenolic acids and flavonoids. PVA nanofibers were fabricated with 30 wt.% flaxseed extract (P70/E30) via electrospinning. We optimized characteristics like diameter, hydrophilicity, swelling behavior, and hydrolytic degradation. MG-63 osteoblast cultures were used to assess scaffold efficacy through cell adhesion, proliferation, viability (MTT assay), and differentiation. RT-qPCR measured expression of osteogenic genes RUNX2, COL1A1, and OCN. Results: Flaxseed extract increased nanofiber diameter from 252nm (pure PVA) to 435nm (P70/E30). P70/E30 nanofibers showed higher cell viability (102.6% vs. 74.5% for pure PVA), although adhesion decreased (151 vs. 206 cells/section). Notably, P70/E30 enhanced osteoblast differentiation, significantly upregulating RUNX2, COL1A1, and OCN genes. Discussion: Flaxseed extract incorporation into PVA nanofibers enhances bone tissue engineering by boosting osteoblast proliferation and differentiation, despite reduced adhesion. These properties suggest P70/E30's potential for regenerative medicine, emphasizing scaffold optimization for biomedical applications.

Preparation and characterization of poly(vinyl pyrrolidone)/cellulose nanofiber/Aloe Vera composites as a biocompatible hydrating facial mask

This study aimed to enhance the properties of polyvinylpyrrolidone (PVP) for use as biocompatible facial masks. To achieve this, nanofibers were developed by blending PVP with cellulose nanofibers (CNFs) and Aloe vera (AV) powder using electrospinning. The results showed that incorporating CNFs and AV into the PVP matrix led to the formation of smooth and uniform nanofibers. In particular, adding 3–6 wt% AV powder in PVP/CNF composites improved fiber diameter distribution and uniformity compared to pure PVP. The PVP/CNF/AV nanofibers exhibited desirable properties for facial mask applications. They displayed 86–93 % porosity, which allowed for efficient moisture absorption capacity of up to 1829 %, and excellent water vapor permeability rate of 3.92 g/m2h. The mechanical properties of the electrospun nanofiber composites were evaluated through tensile testing. The results showed that Young's modulus values decreased progressively with the addition of CNFs and AV powder to the PVP polymer matrix, indicating a plasticizing effect that enhances flexibility. The fracture strain remained similar across all composites, suggesting that CNFs and AV did not significantly weaken the PVP matrix. The tensile strength initially increased with CNF addition but decreased with incremental AV loading. Biocompatibility studies revealed that all nanofibers exhibited excellent fibroblast viability, surpassing 98 %. This indicates that incorporating CNFs and AV did not compromise cell viability, further highlighting the suitability of the PVP/CNF/AV composites for facial mask applications.

Design and fabrication of highly aligned poly(l‐lactide‐co‐ε‐caprolactone) nanofiber yarns and braided textiles

AbstractAn approach that combines a modified electrospinning method with thermal stretching post‐treatment is designed to fabricate poly(l‐lactide‐co‐ε‐caprolactone) (PLCL) electrospun nanofiber yarns (ENYs). The nanofiber diameter in the PLCL ENYs is found to present an increasing trend with the increasing of polymeric concentration. When the PLCL concentration reaches 13% (w/v), the as‐generated ENYs show bead‐free and uniform nanofibrous structure. Then, a thermally stretching technique is applied to process the primarily‐obtained PLCL ENYs. When the stretching temperature is set as 60 °C, the thermally‐stretched PLCL ENYs present superior fiber orientation and notably enhanced crystallinity, thus resulting in dramatically increased mechanical properties. Finally, the thermally stretched PLCL ENYs are further processed into braided fabrics, and their mechanical properties are found to possess an obviously increased trend with the increasing of ENY numbers, demonstrating the adjustment feasibility of the mechanical properties of ENY‐based textiles by controlling the ENY numbers. Importantly, the in vitro cell studies demonstrate that the ENY‐based braided textiles significantly support the adhesion and proliferation of human dermal fibroblasts (HDFs). In all, the present study provides an easily‐handling strategy to fabricate high performance PLCL ENYs, which shows promising future for the generation of advanced biomedical textiles.

Electrospun nanofibers functionalized with metal–organic frameworks/graphene oxide for enrichment of trace-level pesticide residues in food samples

Electrospun nanofibers functionalized with metal–organic frameworks/graphene oxide for enrichment of trace-level pesticide residues in food samples

Flexible Tribo‐Enhanced Piezoelectric Nanogenerator Based on Aluminium Ferrite Electrospun Hybrid Nanofibers for Energy Harvesting and Patient Rehabilitation Application

AbstractMechanical energy harvesters have recently emerged as promising options for self‐powering sensors and small electronic devices. In this work, aluminum ferrite (AlFeO3)/PVDF hybrid perovskite electrospun nanofiber‐based tribo‐enhanced piezoelectric nanogenerators (TPENGs) are developed for energy harvesting. The as‐fabricated TPENG achieves an average voltage output of 52.3 V and an average current output of 1.23 µA. Additionally, the power density of the TPENG is calculated to be 0.085 W.m−2 at an 80 MΩ external resistance load. A 3D‐printed device is fabricated, containing nylon fabric (tribo‐positive) as a rotor attached to printed fins, while six (AlFeO3)/PVDF hybrid perovskite electrospun nanofiber piezoelectric nanogenerators (PENGs) wrapped with Kapton tape (tribo‐negative) serve as the stator. The three printed fins of the device are moved by a string‐based pulley, generating an open circuit voltage of 200 V and a short circuit current of 4.5 µA. The as‐fabricated 3D‐printed device with TPENGs is used to power small electronics (e.g., LEDs and watch) and an exercise setup, allowing patients to generate power by pulling the attached string, thereby estimating the level of impairment. Integrating energy harvesting into rehabilitation motivates patients to move impaired body parts, enhancing TPENG's application in healthcare as a practical and engaging tool for patient rehabilitation.

Nanofiber-based delivery of evodiamine impedes malignant properties of intrahepatic cholangiocarcinoma cells by targeting HDAC4 and restoring TPM1 transcription.

The electrospun nanofiber system is correlated with high efficacy of drug delivery. This study aims to investigate the effect of nanofiber-based delivery of evodiamine, an indole alkaloid derived from Rutaceae plants Evodia rutaecarpa (Juss.) Benth, on intrahepatic cholangiocarcinoma (ICC), as well as to explore the molecular mechanisms. An electrospun nanofiber system carrying evodiamine was generated. Compared to evodiamine treatment alone, the nano-evodiamine exhibited more pronounced effects on suppressing proliferation, colony formation, invasiveness, migration, apoptosis resistance, cell cycle progression, and in vivo tumorigenesis of two ICC cell lines (HUCC-T1 and RBE). ICC cells exhibited increased expression of histone deacetylase 4 (HDAC4) while decreased tropomyosin 1 (TPM1). HDAC4 suppressed TPM1 expression by removing H3K9ac modifications from its promoter. Nano-evodiamine reduced HDAC4 protein levels in ICC cells, thus promoting transcription and expression of TPM1. Either overexpression of HDAC4 or downregulation of TPM1 negated the tumor-suppressive effects of nano-evodiamine. Collectively, this study demonstrates that the electrospun nanofiber system enhances the efficiency of evodiamine. Additionally, evodiamine suppresses the malignant properties of ICC cells. The findings may provide fresh insights into the application of electrospun nanofiber system for drug delivery and the effects of evodiamine on tumor suppression.

Development of novel intelligent and edible dual-functional electrospun nanofiber films for shrimp preservation and freshness monitoring in real-time

The developed trend of novel intelligent packaging materials is changing from food traditional appearance detection to actual spoilage monitoring, aiming to supply a strategy to determine the edibility of food. In this work, a dual-functional electrospun nanofiber film (NFM) noted GZAT was prepared by the co-loading of anthocyanin (ANT) and thymol (THY) into polymer fibers of gelatin and zein. The prepared film was extensively characterized. The GZAT film displayed enhanced mechanical properties and decreased water vapor permeability (WVP) compared with gelatin/zein film (the control). The GZAT film also displayed excellent sensitive colorimetric responses to the pH solutions. Moreover, it exhibited excellent antioxidant property and antibacterial behavior against Escherichia coli ATC25922 (E. coli), Listeria monocytogenes ATCC 19115 (L. monocytogenes) and Staphylococcus aureus ATCC 6538 (S. aureus). Not only that, the dual functions of the GZAT film were confirmed that the shelf life of packaged shrimps was successfully extended to 11 days at 4 °C along with the colorimetric response indicating the freshness of the shrimps. Based on the above characteristic, the prepared GZAT film exhibited great potential as an intelligent packaging film with both real-time freshness indicator and freshness preservation.

Stable and effective photo-Fenton catalysts of Fe-alginate/PVDF composite electrospun nanofibers for the removal of methylene blue

Stable and effective photo-Fenton catalysts of Fe-alginate/PVDF composite electrospun nanofibers for the removal of methylene blue

Development of quercetin-loaded electrospun nanofibers through shellac coating on gelatin: Characterization, colon-targeted delivery, and anticancer activity

Quercetin possesses multiple biological activities. To achieve efficient colon-specific release of quercetin, new composite nanofibers were developed by coating pH-responsive shellac on hydrophilic gelatin through coaxial electrospinning. These composite nanofibers contained bead-like structures. The encapsulation efficiency (87.6–98.5 %) and loading capacity (1.4–4.1 %) varied with increasing the initial quercetin addition amount (2.5–7.5 %). FTIR, XRD, and TGA results showed that the quercetin was successfully encapsulated in composite nanofibers in an amorphous state, with interactions occurring among quercetin, gelatin, and shellac. Composite nanofibers had pH-responsive surface wettability due to the shellac coating. In vitro digestion experiments showed that these composite nanofibers were highly stable in the upper gastrointestinal tract, with quercetin release ranging from 4.75 % to 12.54 %. In vivo organ distribution and pharmacokinetic studies demonstrated that quercetin could be sustainably released in the colon after oral administration of composite nanofibers. Besides, the enhanced anticancer activity of composite nanofibers was confirmed against HCT-116 cells by analyzing their effect on cell viability, cell cycle, and apoptosis. Overall, these novel composite nanofibers could deliver efficiently quercetin to the colon and achieve its sustained release, thus potential to regulate colon health. This system is also helpful in delivering other bioactives to the colon and exerting their functional effects.

Highly selective and sensitive colorimetric chemosensor using PVA/chitosan ion-imprinted nanofibers for copper ion detection and removal

Herein, a highly efficient colorimetric chemosensor incorporating ion-imprinted electrospun nanofiber was developed for the removal and detection of Cu2+ ions. In this regard, PVA/chitosan composites were used as the polymeric matrix, and 1-(2-pyridylazo)-2-naphthol was employed for complex formation. The prepared naked-eye sensor was characterized using Fourier transform infrared spectroscopy, energy-dispersive X-ray spectroscopy, scanning electron microscopy, atomic force microscopy, differential scanning calorimetry, thermogravimetric analysis, and X-ray diffraction analysis, revealing the morphological, structural, and molecular properties of the sensor.The results showed that the colorimetric chemosensor based on copper-imprinted nanofiber (Cu–INF) possesses higher selectivity for Cu2+ compared to interference ions. The selectivity coefficient (k) and relative selectivity coefficient (K′) indicated the selective behavior of Cu–INF in the adsorption of Cu2+ in binary systems including Cu2+/Co2+, Cu2+/Ni2+, and Cu2+/Zn2+.Furthermore, the ion-imprinted nanofiber was used for the preconcentration of copper ions, demonstrating a high adsorption capacity of 128.205 mg g−1 for Cu2+. The equilibrium adsorption isotherm and adsorption kinetics of Cu2+ on Cu–INF followed the Freundlich adsorption isotherm and a pseudo-second-order model, respectively. The developed sensor exhibited a linear detection range of 5 × 10−8 - 2 × 10−7 M with a limit of detection (LOD) of 1.07 × 10−8 M for copper ions. The results indicated satisfactory adsorption and successful detection of Cu2+ at trace concentrations.

Advances and Challenges in Immune-Modulatory Biomaterials for Wound Healing Applications.

Wound healing progresses through three distinct stages: inflammation, proliferation, and remodeling. Immune regulation is a central component throughout, crucial for orchestrating inflammatory responses, facilitating tissue repair, and restraining scar tissue formation. Elements such as mitochondria, reactive oxygen species (ROS), macrophages, autophagy, ferroptosis, and cytokines collaboratively shape immune regulation in this healing process. Skin wound dressings, recognized for their ability to augment biomaterials' immunomodulatory characteristics via antimicrobial, antioxidative, pro- or anti-inflammatory, and tissue-regenerative capacities, have garnered heightened attention. Notwithstanding, a lack of comprehensive research addressing how these dressings attain immunomodulatory properties and the mechanisms thereof persists. Hence, this paper pioneers a systematic review of biomaterials, emphasizing immune regulation and their underlying immunological mechanisms. It begins by highlighting the importance of immune regulation in wound healing and the peculiarities and obstacles faced in skin injury recovery. This segment explores the impact of wound metabolism, infections, systemic illnesses, and local immobilization on the immune response during healing. Subsequently, the review examines a spectrum of biomaterials utilized in skin wound therapy, including hydrogels, aerogels, electrospun nanofiber membranes, collagen scaffolds, microneedles, sponges, and 3D-printed constructs. It elaborates on the immunomodulatory approaches employed by these materials, focusing on mitochondrial and ROS modulation, autophagic processes, ferroptosis, macrophage modulation, and the influence of cytokines on wound healing. Acknowledging the challenge of antibiotic resistance, the paper also summarizes promising plant-based alternatives for biomaterial integration, including curcumin. In its concluding sections, the review charts recent advancements and prospects in biomaterials that accelerate skin wound healing via immune modulation. This includes exploring mitochondrial transplantation materials, biomaterial morphology optimization, metal ion incorporation, electrostimulation-enabled immune response control, and the benefits of composite materials in immune-regulatory wound dressings. The ultimate objective is to establish a theoretical foundation and guide future investigations in the realm of skin wound healing and related materials science disciplines.

Impact of pH and ZnO NPs on the fabricated PVA-PVP/ZnO nanofibers: Morphology, absorption behavior, anticancer, and antibacterial activity

In this study, a cost-effective hydrothermal method was successfully used to synthesize ZnO NPs at different pH levels (8, 10, and 12). Nanofibers were produced from polymeric blends PVA-PVP and PVA-PVP/ZnO nanocomposite precursor through electrospinning. XRD analysis revealed the hexagonal wurtzite structure of the synthesized ZnO NPs, with the dominant crystal plane (101). The impact of pH variation was evident in the increased intensity values of the peaks corresponding to (100), (002), and (101) planes as pH levels rose. The average crystallite size decreased from 31.4 to 27.0 nm using Scherrer's calculation, while the microstrain increased from 11.2 to 12.4 ×10−4 as the pH increased from 8 to 12. As wellas the average particle size of the ZnO NPs decreased from 75.05 to 51.35 nm with increasing pH levels, as depicted in FESEM images. The PVA-PVP/ZnO electrospun nanofibers exhibited smooth surfaces and uniform structures, with average diameters of 80.14, 93.33, and 124.13 nm for pH 8, 10, and 12, respectively. The calculation of the optical energy gap using the ASF approach closely matched Tauc's model, ranging from 3.57 to 3.20 eV. Evaluation of the anticancer activity of the nanofibers against MCF-7 cells showed an increase in cytotoxicity from 18 to 64 % with varying concentrations of ZnO NPs ranging from 6.25 to 100 μg/ml. The highest inhibitory effect (about 16 mm) was observed at pH 12 against gram-positive (Staphylococcus aureus).

Poly(3-Hydroxybutyrate-co-3-Hydroxyvalerate) Self-Reinforced Composites via Solvent-Induced Interfiber Welding of Nanofibers.

In this study, we explore an approach to enhance the mechanical performance of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) by utilizing the self-reinforcing effect of β-phase-induced PHBV electrospun nanofiber mats. This involves electrospinning combined with low-temperature postspun vapor solvent interfiber welding. Scanning electron microscopy imaging confirmed fiber alignment, while XRD diffraction revealed the presence of both α and β crystalline phases under optimized electrospinning conditions. The resulting composite exhibited significant improvements in mechanical properties attributed to the formation of more perfectly structured α and β polymorphs and enhanced interfacial adhesion of electrospun nanofibers after vapor solvent treatment. This approach offers entirely recyclable and biodegradable materials, presenting the potential for a new family of sustainable bioplastics.

Development of sinomenine hydrochloride loaded shell/core nanofibrous with pH‐responsive for colon‐targeted drug delivery

AbstractA series of colon‐targeted, sustained‐release, sinomenine hydrochloride (SH) loaded shell/core electrospun nanofibers are reported. The fibers have shells made of Eudragit S100 (ES‐100), and drug‐loaded cores comprising of Eudragit RS100 (ERS‐100) and SH. The essential characteristics of membranes are evaluated by scanning electron microscopy, transmission electron microscope, Fourier transformed infrared spectroscopy, and x‐ray diffraction. In vitro release of SH show that the shell/core nanofiber membranes can block drug release in the HCl buffer (pH 1.2), and the release time of the hydrophilic drug SH exceed 240 min at pH 7.4 phosphate buffer solution. In vitro drug release kinetics consistent with the first‐order model. The shell/core nanofiber can achieve colon‐targeted and sustained‐release properties, which can better prevent the loss of SH and relieve the adverse effects on gastrointestinal tract. In addition, the hemolysis and cytotoxicity tests manifest that the nanofiber membrane display good hemocompatibility and cytocompatibility. These results suggest the SH‐containing nanofiber membranes have potential applications as a colon‐targeted drug delivery system that sustained release. They also offer a theoretical foundation for the development of novel dosage forms for SH.

Electrospun PCL/PVA/PHMB nanofibers incorporating Ziziphus jujuba fruit extract as promising wound dressings with potent antibacterial and antidiabetic properties

This investigation examined the potential antibacterial and antidiabetic effects of wound dressings created using electrospun nanofibers containing Ziziphus jujuba fruit extract (ZJ). These nanofibers were composed of a combination of Polycaprolactone (PCL), Polyvinyl Alcohol (PVA), and Polyhexamethylene Biguanide (PHMB). The process of creating these nanofibers involved electrospinning. The nanofiber products, which included PCL, PCL/PVA, PCL/PVA/ZJ, PCL/PVA/PHMB, and PCL/PVA/PHMB/ZJ, underwent a morphology, physicochemical, and biological assessment. Incorporating PHMB into the nanofibers enhanced the antibacterial properties, effectively preventing bacterial infections in wounds. Furthermore, including ZJ fruit extract in the nanofibers provided antidiabetic properties, making these dressings suitable for diabetic patients. The PCL/PVA/PHMB/ZJ combination exhibited exceptional healing capabilities and superior antibacterial efficiency in MRSA-infected wounds. The histological assay confirmed complete wound healing by day 14, accompanied by reduced inflammation. Based on these findings, using PCL/PVA/PHMB/ZJ as innovative wound dressings is recommended, as they can expedite wound healing while offering significant antidiabetic and antibacterial features. Ultimately, these electrospun nanofibers possess the potential to serve as advanced wound dressings with enhanced antibacterial and anti-diabetes properties.

Electrospun Cellulose Acetate/Maleic Acid Functionalized Gold Nanoparticles as Pb(II) Ions Colorimeter Senser Strip

This study investigates the synthesis of gold nanoparticles and surface modifications to enable their utilization as a colorimetric sensor strip on electrospun nanofibrous. Additionally, it utilizes cellulose acetate electrospun fiber preparations as substrates for loading the gold nanoparticles. In order to produce gold nanoparticles, citrate reduction was employed, followed by modification with maleic acid (MA-GNPs). MA-GNPs were significantly more selective for Pb2+ than for other ions (Co2+, Cu2+, Hg2+, Ni+), according to the results. Following the introduction of Pb2+, the solutions exhibited a color change from red to blue or purple, which was attributed to the aggregation of nanoparticles, as determined by UV-Vis spectrometry. An optical band indicative of GNPs and MA-GNPs was detected at an estimated wavelength of 520 nm. Approximately 600 nanometers after the addition of Pb2+, the intensity of the solution progressively decreased to 520 nanometers, and a new band emerged. To fabricate cellulose acetate nanofibrous via electrospinning, the impact of solvent ratios, polymer concentrations, and process conditions were investigated. The ideal parameters for the fabrication of the substrate were as follows: 15%w/w polymer solution, 15 kV electrospinning voltage, 15 cm needle-to-collector distance, and 48 hours of collecting time. In order to examine the color change of the prepared strip, it is observed that the strip transforms from red to blue upon exposure to Pb2+ ions of varying concentrations, just as it does in solution form. An examination of water samples indicated that the strip remained colorless when tested with DI water. However, testing with wastewater sourced from a battery facility identified a transformation of the strip from red to purplish blue. This is equivalent to an estimated lead concentration of 40 parts per million. The outcomes showcased the capacity of the discolored strips to identify the preliminary concentration of lead ions, suggesting potential for future advancements in this area.

A ternary composite nanofibrous photocatalyst: FcLR-gC3N4/polyisothianaphthene/polyacrylonitrile for degradation of organic dyes

BackgroundWater pollution by organic dyes is one of the important environmental issues. When substances such as organic dyes are discharged into water, they can severely pollute the water and harm the life of living organisms. MethodsA new ternary composite nanofibrous photocatalyst, FcLR-gC3N4/PITN/PAN, was produced through 1) synthesis of a graphitic carbon nitride (g-C3N4)-based ferrocenyl dithiophosphonic acid, FcLR-gC3N4, by the attachment of Ferrocenyl Lawesson's Reagent (FcLR) to g-C3N4 nanosheets, 2) incorporation of the FcLR-gC3N4 into the polymeric matrix of as-prepared polyisothianaphthene (PITN) blending with polyacrylonitrile (PAN), and 3) fabrication of electrospun nanofibers (NFs) through electrospinning. Significant findingsThe degradation of methyl orange (MO) and methylene blue (MB) was more efficient on FcLR-gC3N4 compared to g-C3N4 alone, and on FcLR-gC3N4/PITN/PAN compared to FcLR-gC3N4, confirming the effective role of both FcLR and PITN/PAN matrix in the degradation of the dyes. The ternary composite nanofiber degraded 92% of MB and 29% of MO. The MB mineralization percentages of 65% (TOC), 60% (COD), and 55% (BOD) were achieved after 2 h and 30 min. Radical trapping experiments consistent with the Tauc plots and Mott-Schottky plots distinguished O2•- as the primary species in the degradation mechanism of MB. The MB degradation pathway was determined through LC-MS-MS. The electrochemical impedance spectrum (EIS) and photocurrent measurements confirmed the higher photocatalytic activity of FcLR-gC3N4 compared to g-C3N4 alone by studying the charge carrier's separation and recombination. A high recyclability was found for FcLR-gC3N4. The recycling stability of FcLR-gC3N4 increased after its embedding into the nanofibrous matrix of PITN/PAN.

Improving Chitosan/PVA Electrospun Nanofibers Antimicrobial Efficacy with Methylene Blue for Effective <i>E. Coli</i> Inhibition Using Photodynamic Therapy

In view of the growing concern over the threat of antibiotic resistance and bacterial infections, this study evaluated the antimicrobial performance and characteristics of chitosan/polyvinyl alcohol (PVA) nanofibers incorporated with Methylene Blue (MB). Following the fabrication of chitosan/PVA nanofibers loaded with different MB concentrations via electrospinning, the samples were characterised through Field-emission Scanning Electron Microscopy (FESEM), Fourier Transform Infrared (FTIR) spectroscopy, and leaching tests. Finally, the antimicrobial inhibition level of the samples was assessed via the disc diffusion method. Based on the results, the MB-integrated chitosan/PVA nanofibers exhibited a nanoscale morphology, and the FTIR confirmed the presence of MB. The findings also established a positive correlation between the MB concentration and leaching intensity. Furthermore, the optimal antimicrobial efficacy against Escherichia coli was achieved by the chitosan/PVA/MB (5 wt.%) sample with a 2-min laser exposure, which recorded a significant inhibition zone of 8.65 mm. In conclusion, MB demonstrated potent antimicrobial properties against E. coli, suggesting its potential integration in electrospun nanofibers for combating bacterial infections via photodynamic therapy.

Thermally Stabilised Poly(vinyl alcohol) Nanofibrous Materials Produced by Scalable Electrospinning: Applications in Tissue Engineering.

Electrospinning is a widely employed manufacturing platform for tissue engineering applications because it produces structures that closely mimic the extracellular matrix. Herein, we demonstrate the potential of poly(vinyl alcohol) (PVA) electrospun nanofibers as scaffolds for tissue engineering. Nanofibers were created by needleless direct current electrospinning from PVA with two different degrees of hydrolysis (DH), namely 98% and 99% and subsequently heat treated at 180 °C for up to 16 h to render them insoluble in aqueous environments without the use of toxic cross-linking agents. Despite the small differences in the PVA chemical structure, the changes in the material properties were substantial. The higher degree of hydrolysis resulted in non-woven supports with thinner fibres (285 ± 81 nm c.f. 399 ± 153 nm) that were mechanically stronger by 62% (±11%) and almost twice as more crystalline than those from 98% hydrolysed PVA. Although prolonged heat treatment (16 h) did not influence fibre morphology, it reduced the crystallinity and tensile strength for both sets of materials. All samples demonstrated a lack or very low degree of haemolysis (<5%), and there were no notable changes in their anticoagulant activity (≤3%). Thrombus formation, on the other hand, increased by 82% (±18%) for the 98% hydrolysed samples and by 71% (±10%) for the 99% hydrolysed samples, with heat treatment up to 16 h, as a direct consequence of the preservation of the fibrous morphology. 3T3 mouse fibroblasts showed the best proliferation on scaffolds that were thermally stabilised for 4 and 8 h. Overall these scaffolds show potential as 'greener' alternatives to other electrospun tissue engineering materials, especially in cases where they may be used as delivery vectors for heat tolerant additives.

Graphene oxide (GO)-reinforced curcumin (CUR)-loaded zein-based electrospun nanofibers for potential wound dressing purposes

This work produced graphene oxide (GO)-reinforced curcumin (CUR)-loaded zein-based electrospun nanofibers. FTIR and XRD analyses confirmed the formation of interaction between zein, GO, and CUR. However, other than entanglement changes, as confirmed by DSC analysis, this composite formation had little effect on the thermal stability, surface polarity, and crystallinity of the fibers. Meanwhile, the addition of GO increased the tensile strength of the fibers from (0.83 ± 0.19) to (6.87 ± 2.47) MPa, but the incorporation of CUR decreased it to ≈ 2.71 MPa. Cytocompatibility tests confirmed the growth of cells throughout the fibers; release assays indicated a two-stage release. Combined with the low swelling capacity (< 1 g g−1), the fibers absorb exudates, release bioactive molecules into the wound, give the body time to metabolize the released drug, and allow cell proliferation, creating a suitable environment for healing. Despite these results, in vivo are still prospects of this work.