Electrospinning Technique Research Articles

The Effect of Aligned and Random Electrospun Fibers Derived from Porcine Decellularized ECM on Mesenchymal Stem Cell-Based Treatments for Spinal Cord Injury.

The impact of traumatic spinal cord injury (SCI) can be extremely devastating, as it often results in the disruption of neural tissues, impeding the regenerative capacity of the central nervous system. However, recent research has demonstrated that mesenchymal stem cells (MSCs) possess the capacity for multi-differentiation and have a proven track record of safety in clinical applications, thus rendering them effective in facilitating the repair of spinal cord injuries. It is urgent to develop an aligned scaffold that can effectively load MSCs for promoting cell aligned proliferation and differentiation. In this study, we prepared an aligned nanofiber scaffold using the porcine decellularized spinal cord matrix (DSC) to induce MSCs differentiation for spinal cord injury. The decellularization method removed 87% of the immune components while retaining crucial proteins in DSC. The electrospinning technique was employed to fabricate an aligned nanofiber scaffold possessing biocompatibility and a diameter of 720 nm. In in vitro and in vivo experiments, the aligned nanofiber scaffold induces the aligned growth of MSCs and promotes their differentiation into neurons, leading to tissue regeneration and nerve repair after spinal cord injury. The approach exhibits promising potential for the future development of nerve regeneration scaffolds for spinal cord injury treatment.

One-step synthesis of double-walled NiCo2O4 hollow nanotubes using hollow fiber templates created by airflow-coaxial electrospinning

Metal oxide electrode material NiCo2O4 has significant potential for application as an Electrode material due to its excellent electrochemical performance and environmentally friendly characteristics. This paper utilizes a unique airflow-coaxial electrospinning technique combined with a simple one-step solution reaction to prepare NiCo2O4 nanotubes with a complex double-walled hollow structure. The XPS and XRD results demonstrated the synthesis of the NiCo2O4 materials, while the SEM and TEM results verified the presence of a double-walled hollow structure in the NiCo2O4 nanotubes. The electrochemical performance of the NiCo2O4 double-walled hollow nanotubes is significantly improved compared to those single-layer hollow nanotubes. The maximum specific capacitance of those two kinds of nanotubes is 437.5 F/g and 336.7 F/g under the current density of 1 A/g, respectively. The origin of the electrochemical performance improvement can be attributed to the increased specific surface area and the presence of interlayer ion transport channels in the double-walled hollow structure. The study is very helpful in improving the application prospect of NiCo2O4 material as the electrode material of supercapacitors. Equally important, this study also presents an efficient method to fabricate double-walled hollow nanostructures based on special templates.

Improved UV-Vis Detector Performance Prepared via the Electrospinning Technique by Doping Polymer Solutions with Iron Oxide

The iron (III) oxide nanoparticles (NPs) were prepared by a solvent-controlled method when preparing the electrospinning solution. Nanofibers (NFs) were prepared from pure PVP and PVP doped with ratios 1 %wt., 2 %wt. and 3 %wt. of Fe2O3 NPs at room temperature by the electrospinning technique. Optical properties like absorbance and the band energy gap ([Formula: see text]g) were studied, and the direct band gap of pure PVP NFs is 4.07 eV and decreases slightly with increasing concentration of Fe2O3 NPs. The PVP NFs with Fe2O3 NPs were used as a UV-Vis light detector with good responsivity and specific detectives at a mixing rate of 3% Fe2O3 NPs, which was 12 A/W and 27.76 ×10[Formula: see text] Jones at wavelength 458.3 nm, and also had the lowest values for the rise-time and fall-time.

Second harmonic generation and reverse saturable absorption in electrospun picric Acid-PMMA nanofibers

Picric acid (PA) – polymethyl methacrylate (PMMA) nanofibers were synthesised using electrospinning technique by optimising all the required parameters. The nonlinear optical behaviour of the synthesised nanofibers was investigated along with their preliminary characterisations like morphological, structural, thermal, mechanical, dielectric and linear optical studies. The nanofibers with average diameter around ∼800 nm, were found to crystallise in Pca21 space group under the orthorhombic crystal system. The incorporation of Picric acid nanocrystals inside the PMMA nanofibers enhanced their tensile strength. Second harmonic generation imaging of picric acid embedded PMMA nanofibers was done by nonlinear microscopy and the emission was confirmed by power dependence as well as Kurtz – Perry powder technique. Nonlinear absorption studies by Z – scan technique were conducted with a Q – switched Nd: YAG laser and the nanofibers exhibited reverse saturable absorption nature at all the input intensities (0.616 × 1012 W/m2, 1.23 × 1012 W/m2 and 2.46 × 1012 W/m2) and the value of the nonlinear absorption coefficient increased corresponding to an increase in input intensity (0.98 × 10−10 m/W, 1.39 × 10−10 m/W and 1.61 × 10−10 m/W) owing to a sequential two photon absorption. Using the transmittance data optical limiting properties of the nanofibers were also analysed and the limiting threshold values (1.92 × 1012 W/m2, 1.80 × 1012 W/m2 and 1.54 × 1012 W/m2) at respective intensities were extracted. The low optical limiting threshold obtained in the present case confirms that picric acid – PMMA nanofibers can be an assured contender as optical limiters in laser safety devices.

From Synthesis to Functionality: Tailored Ionic Liquid-Based Electrospun Fibers with Superior Antimicrobial Properties.

Herein, we report an efficient and facile strategy for the preparation of imidazolium-based ionic liquid (IL) monomers ([CnVIm][Br], n = 2, 4, 6, 8, 10, and 12) and their corresponding polymeric ionic liquids (PILs) with potent antimicrobial activities against Gram-negative and Gram-positive bacteria and fungi. The electrospinning technique was utilized to tailor the polymers with the highest antimicrobial potency into porous membranes that can be easily implemented into diverse systems and extend their practical bactericidal application. The antimicrobial mechanism of obtained ILs, polymers, and nanomaterials is considered concerning the bearing chain length, polymerization process, and applied processing technique that provides a unique fibrous structure. The structure composition was selected due to the well-established inherent amphiphilicity that 1-alkylimidazolium ILs possess, coupled with proven antimicrobial, antiseptic, and antifungal behavior. The customizable nature of ILs and PILs complemented with electrospinning is exploited for the development of innovative antimicrobial performances born from the intrinsic polymer itself, offering solutions to the increasing challenge of bacterial resistance. This study opens up new prospects toward designer membranes providing a complete route in their designing and revolutionizing the approach of fabricating multi-functional systems with tunable physicochemical, surface properties, and interesting morphology.

One-step fabrication of Polyvinylidene fluoride membranes enriched with electroactive β-Phase for secondary battery separators via simultaneous near infrared radiation and electrospinning

This study reports a one-step fabrication method to prepare polyvinylidene fluoride (PVDF) membranes enriched with electroactive β-Phase in application for secondary battery separator using near infrared radiation (NIR) heated electrospinning techniques. The electrospun PVDF fibrous membranes with NIR heating applied were investigated by various characterizations and measurements. The results present that NIR heating during electrospinning not only increased the β phase content and mechanical strength of the PVDF membranes but also improved the electrochemical performances, suggesting its potential suitability in the battery separator applications.

An electrospun iron oxychloride/polyacrylonitrile nanofibrous membrane with superhydrophilic and excellent regeneration properties: Achieving superior oil-in-water emulsion separation

Superhydrophilic polymer membranes are widely used in oil-water separation due to their excellent wettability, high efficiency, low cost, and good biocompatibility. However, challenges such as fouling adhesion and inadequate stability persist during the treatment of oily wastewater. Herein, a novel iron oxychloride/polyacrylonitrile (FeOCl/PAN) nanofibrous membrane with superhydrophilicity and remarkable regenerability was successfully fabricated through simple electrospinning technique, which maintained good physicochemical stability under various harsh conditions with the uniform distribution of FeOCl on PAN fibers. The surface morphology and chemical compositions of the optimized FeOCl/PAN membrane were studied by several characterization techniques. The introduced FeOCl nanocrystals through electrospinning endowed the membrane with a rougher surface structure, significantly improving the hydrophilicity of the FeOCl/PAN nanofibrous membrane. In the cross-flow isooctane-in-water emulsion separation experiment, the initial water flux recovery rate (FRR) of the membrane increased from 92 % for the pure PAN membrane to around 99 %. Meanwhile, the optimized FeOCl/PAN nanofibrous membrane achieved an emulsion (isooctane) flux of approximately 632.9 L m−2 h−1, with an oil droplet removal rate surpassing 99.4 %. Furthermore, by cleaning the membrane with H2O2 (60 mM, pH = 3), the FeOCl/PAN membrane exhibited an exceptionally high water flux recovery rate (∼100 %) after high-concentration paraffin-in-water emulsion (4000 mg L−1) separation. In addition, the FeOCl/PAN membrane also demonstrated excellent antifouling performance in bovine serum albumin (BSA) pollution experiment. In summary, this work might provide a unique strategy for preparing advanced functional membranes with superior efficiency and durability for emulsified oily wastewater treatment.

Simultaneous improvements in energy density and thermal conductivity of PAN polymer nanocomposites enabled by core-shell structure BZCT@BNNS nanofibers

If the heat generated by electronic devices in high-power applications cannot be dissipated in a timely manner, it will not only affect the use of the equipment but also reduce its service life. Therefore, there is an urgent need to develop thin films of dielectric nanocomposites with high thermal conductivity, high energy storage, and excellent flexibility and electrical insulation performance. In this study, we reported the successful preparation of BZCT nanofibers (BZCT NFs) and core-shell structures BZCT@BNNS nanofibers using electrospinning and coaxial electrospinning techniques, respectively, and there were used to composite with polyacrylonitrile (PAN) polymer matrix to prepare BZCT NFs/PAN and BZCT@BNNS/PAN dielectric nanocomposites thin film. Research has found that when the shell thickness of BNNS is 15 nm and BZCT@BNNS (15 nm) volume fraction is 20 vol%, the comprehensive performance of the dielectric nanocomposites is the best, with thermal conductivity and energy storage performance of 3.36 W m−1K−1 and 12.23 J/cm3, respectively. Therefore, the nanocomposites thin film can be used as a potential high-performance dielectric material for thermal management applications in high-power density electronic devices.

Fabrication of Electrospun Double Layered Biomimetic Collagen-Chitosan Polymeric Membranes with Zinc-Doped Mesoporous Bioactive Glass Additives.

Several therapeutic approaches have been developed to promote bone regeneration, including guided bone regeneration (GBR), where barrier membranes play a crucial role in segregating soft tissue and facilitating bone growth. This study emphasizes the importance of considering specific tissue requirements in the design of materials for tissue regeneration, with a focus on the development of a double-layered membrane to mimic both soft and hard tissues within the context of GBR. The hard tissue-facing layer comprises collagen and zinc-doped bioactive glass to support bone tissue regeneration, while the soft tissue-facing layer combines collagen and chitosan. The electrospinning technique was employed to achieve the production of nanofibers resembling extracellular matrix fibers. The production of nano-sized (~116 nm) bioactive glasses was achieved by microemulsion assisted sol-gel method. The bioactive glass-containing layers developed hydroxyapatite on their surfaces starting from the first week of simulated body fluid (SBF) immersion, demonstrating that the membranes possessed favorable bioactivity properties. Moreover, all membranes exhibited distinct degradation behaviors in various mediums. However, weight loss exceeding 50% was observed in all tested samples after four weeks in both SBF and phosphate-buffered saline (PBS). The double-layered membranes were also subjected to mechanical testing, revealing a tensile strength of approximately 4 MPa. The double-layered membranes containing zinc-doped bioactive glass demonstrated cell viability of over 70% across all tested concentrations (0.2, 0.1, and 0.02 g/mL), confirming the excellent biocompatibility of the membranes. The fabricated polymer bioactive glass composite double-layered membranes are strong candidates with the potential to be utilized in tissue engineering applications.

Sodium alginate-based nanofibers loaded with Capparis Sepiaria plant extract for wound healing

Burn wounds are associated with infections, drug resistance, allergic reactions, odour, bleeding, excess exudates, and scars, requiring prolonged hospital stay. It is crucial to develop wound dressings that can effectively combat allergic reactions and drug resistance, inhibit infections, and absorb excess exudates to accelerate wound healing. To overcome the above-mentioned problems associated with burn wounds, SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers incorporated with Capparis sepiaria plant extract were prepared using an electrospinning technique. Fourier-transform infrared spectroscopy confirmed the successful incorporation of the extract into the nanofibers without any interaction between the extract and the polymers. The nanofibers displayed porous morphology and a rough surface suitable for cellular adhesion and proliferation. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers demonstrated significant antibacterial effects against wound infection-associated bacterial strains: Pseudomonas aeruginosa, Enterococcus faecalis, Mycobaterium smegmatis, Escherichia coli, Enterobacter cloacae, Proteus vulgaris, and Staphylococcus aureus. Cytocompatibility studies using HaCaT cells revealed the non-toxicity of the nanofibers. SA/PVA/PLGA/Capparis sepiaria and SA/PVA/Capparis sepiaria nanofibers exhibited hemostatic properties, resulting from the synergistic effect of the plant extract and polymers. The in vitro scratch wound healing assay showed that the SA/PVA/Capparis sepiaria nanofiber wound-healing capability is more than the plant extract and a commercially available wound dressing. The wound-healing potential of SA/PVA/Capparis sepiaria nanofiber is attributed to the synergistic effect of the phytochemicals present in the extract, their porosity, and the ECM-mimicking structure of the nanofibers. The findings suggest that the electrospun nanofibers loaded with Capparis sepiaria extract are promising wound dressings that should be explored for burn wounds.

Influence of photothermal nanomaterials localization within the electrospun membrane structure on purification of saline oily wastewater based on photothermal vacuum membrane distillation

Today, synergistic combination of special nanomaterials (NMs) and electrospinning technique has emerged as a promising strategy to address both water scarcity and energy concerns through the development of photothermal membranes for wastewater purification and desalination. This work was organized to provide a new perspective on membrane design for photothermal vacuum membrane distillation (PVMD) through optimizing membrane performance by varying the localization of photothermal NMs. Poly(vinylidene fluoride) omniphobic photothermal membranes were prepared by localizing graphene oxide nanosheets (GO NSh) (1) on the surface (0.2 wt%), (2) within the nanofibers structure (10 wt%) or (3) in both positions. Considering the case 1, after 7 min exposure to the 1 sun intensity light, the highest temperature (∼93.5 °C) was recorded, which is assigned to the accessibility of GO NSh upon light exposure. The case 3 yielded to a small reduction in surface temperature (∼90.4 °C) compared to the case 1, indicating no need to localize NMs within the nanofibers structure when they are localized on the surface. The other extreme belonged to the case 2 with the lowest temperature of ∼71.3 °C, which is consistent with the less accessibility of GO NSh during irradiation. It was demonstrated that the accessibility of photothermal NMs plays more pronounced role in the membrane surface temperature compared to the light trapping. However, benefiting from higher surface temperature during PVMD due to enhanced accessibility of photothermal NMs is balanced out by decrease in the permeate flux (case 1: 1.51 kg/m2 h and case 2: 1.83 kg/m2 h) due to blocking some membrane surface pores by the binder. A trend similar to that for flux was also followed by the efficiency. Additionally, no change in rejection was observed for different GO NSh localizations.

Enhancement of the chondrogenic differentiation capacity of human dental pulp stem cells via chondroitin sulfate-coated polycaprolactone-MWCNT nanofibers

Most of the conditions involving cartilaginous tissues are irreversible and involve degenerative processes. The aim of the present study was to fabricate a biocompatible fibrous and film scaffolds using electrospinning and casting techniques to induce chondrogenic differentiation for possible application in cartilaginous tissue regeneration. Polycaprolactone (PCL) electrospun nanofibrous scaffolds and PCL film were fabricated and incorporated with multi-walled carbon nanotubes (MWCNTs). Thereafter, coating of chondroitin sulfate (CS) on the fibrous and film structures was applied to promote chondrogenic differentiation of human dental pulp stem cells (hDPSCs). First, the morphology, hydrophilicity and mechanical properties of the scaffolds were characterized by scanning electron microscopy (SEM), spectroscopic characterization, water contact angle measurements and tensile strength testing. Subsequently, the effects of the fabricated scaffolds on stimulating the proliferation of human dental pulp stem cells (hDPSCs) and inducing their chondrogenic differentiation were evaluated via electron microscopy, flow cytometry and RT‒PCR. The results of the study demonstrated that the different forms of the fabricated PCL-MWCNTs scaffolds analyzed demonstrated biocompatibility. The nanofilm structures demonstrated a higher rate of cellular proliferation, while the nanofibrous architecture of the scaffolds supported the cellular attachment and differentiation capacity of hDPSCs and was further enhanced with CS addition. In conclusion, the results of the present investigation highlighted the significance of this combination of parameters on the viability, proliferation and chondrogenic differentiation capacity of hDPSCs seeded on PCL-MWCNT scaffolds. This approach may be applied when designing PCL-based scaffolds for future cell-based therapeutic approaches developed for chondrogenic diseases.

Facile conjugate electro-spinning to achieve nanofiber yarns with concurrent color-tunable photoluminescence and tailored superparamagnetism

In this work, we have successfully fabricated hetero-structured nanofiber yarns (NFYs) with a conjugate electro-spinning technique, integrating a dual-functional capability of tunable color photoluminescence and tailored superparamagnetism. These hetero-structured NFYs are comprised of [Eu(BA)3phen + Tb(BA)3phen]/polyacrylonitrile (PAN) photoluminescent nanofibers (NFs) and Fe3O4/PAN superparamagnetic NFs, which allow for the effective isolation of dark-colored Fe3O4 nanoparticles (NPs) from rare earth complexes. This design leads to enhanced photoluminescent performance for the hetero-structured NFYs. Detailed investigations into the morphologies and performances of these NFYs were conducted using X-ray diffraction (XRD), scanning electron microscopy (SEM), energy-dispersive spectroscopy (EDS), fluorescence spectrophotometry, and vibrating sample magnetometry (VSM). The emitting light color, ranging from red to yellow to green, can be tuned under a specific excitation wavelength (276 nm) of ultraviolet (UV) light by regulating the proportion of rare earth complexes. Furthermore, the superparamagnetism of the NFYs can be tailored by varying the amounts of Fe3O4 NPs. The designing philosophy and preparative technique can be utilized to manufacture other polyfunctional nanomaterials.

Cobalt ferrite-embedded polyvinylidene fluoride electrospun nanocomposites as flexible triboelectric sensors for healthcare and polysomnographic monitoring applications

Human respiration is a vital physiological function of the body and a key metric for assessing overall health, particularly in conditions related to sleep deprivation. However, developing a real-time system for detecting sleeping position, heartbeat, and respiration is challenging yet crucial. Such a system should be easy to fabricate, comfortable to wear, and highly sensitive. In this study, we fabricated a flexible electrospun cobalt ferrite (CoFe2O4, CF) embedded polyvinylidene fluoride (PVDF) nanocomposite (NC) using an electrospinning technique. Additionally, we investigated the influence of varying CF content (0, 1, 3, and 5 wt%) on the crystalline β-phase in PVDF. The triboelectric nanogenerator (TENG) device was fabricated using PVDF-CF (P-CF) NC as the tribo-negative layer and non-woven fabric of thermoplastic polyurethane (TPU) as the tribo-positive layer. Among the four sample combinations used in this study, P-CF-3 (3 wt% CF in PVDF)/TPU TENG exhibited a significantly higher triboelectric open circuit voltage (Voc) of 5.8 V, nearly three times higher as compared to P-CF-0/TPU TENG (1.7 V). This work demonstrates an efficient method for enhancing the output efficacy of flexible TENG devices by varying the nanofiller concentration. Moreover, the fabricated TENG device was efficiently tested for real-time healthcare monitoring (HCM) and polysomnographic (PSG) related studies. This study aspires to provide a novel and pragmatic way of identifying real-time sleeping disorders and respiratory monitoring.

Enhancing fresh strawberry preservation: Fabrication and characterization of electrospun fibers decorated with functionalized graphene oxide

AbstractThis study focuses on developing an innovative packaging material for fresh strawberries composed of electrospun poly(ε‐caprolactone) (PCL)/poly(vinylpyrrolidone) (PVP) fibers decorated by pure graphene oxide (GO) and functionalized GOs with silane agents using the electrospinning technique. Initially, synthesized GO was first functionalized by silane agents, and followed by the fabrication of electrospun PCL/PVP fibers incorporating both pure GO and functionalized GOs. The surface morphological analyses revealed the uniformity, smoothness, and beadless in the fabricated fibers. The average fiber diameter of the PCL/PVP/0.5A‐GO fibers was found as 3244 ± 56 nm. Electrospun PCL/PVP/0.5A‐GO and PCL/PVP/0.5G‐GO fibers exhibited increased water absorption ratios over 20 days. The incorporation of GO into the polymer matrix, along with an increase in GO concentration, enhanced the tensile strength of the fibers, found as 5.149 ± 0.032 kPa. In preservation tests on fresh strawberries, PCL/PVP/0.5A‐GO fibers demonstrated superior freshness compared with unpacked strawberries and other variants. The study also highlighted the inhibitory effects of fibers decorated with 0.5% APTES‐GO, showing the highest inhibition zone. In summary, fibers incorporating 0.5% A‐GO effectively extended the shelf‐life of fresh strawberries, making them a promising packaging material for perishable goods.

Optimization of Biologically Inspired Electrospun Scaffold for Effective Use in Bone Regenerative Applications.

Human bone is composed of organic and inorganic composite materials, contributing to its unique strength and flexibility. Hydroxyapatite (HAP) has been extensively studied for bone regeneration, due to its excellent bioactivity and osteoconductivity, which makes it a highly valuable biomaterial for tissue engineering applications. For better therapeutic effects, composite nanofibers containing polyvinyl alcohol (PVA) and polyvinyl Pyrrolidone (PVP) were developed using an electrospinning technique in this study. Herein, hydroxyapatite (a major inorganic constituent of native bone) concentrations varying from 5 to 25% were reinforced in the composite, which could alter the properties of nanofibers. The as-prepared composite nanofibers were characterized by SEM, TEM, XRD, and FT-IR spectroscopy, and a bioactivity assessment was performed in simulated body fluid (SBF). The ICP-OES analysis was used to determine the concentration of Ca2+ and PO42- ions before and after SBF immersion. To optimize the material selection, the nanofibrous scaffolds were subjected to cell proliferation and differentiation in MG-63 osteoblast cell lines, but no significant toxicity was observed. In conclusion, HAP-PVA-PVP scaffolds exhibit unique physical and chemical properties and ideal biocompatibility, with great promise to serve as effective candidates for bone tissue applications.

A gel polymer electrolyte obtained from cellulose acetate/polyvinylidene fluoride composite electrospun membrane for safe lithium metal batteries with high-rate capability

Li metal battery is a promising next-generation power storage devices, but faces the serious safety issues caused by the uncontrolled Li dendrite growth and leakage of the flammable organic electrolyte. Herein, a low-cost CA/PVDF (cellulose acetate/polyvinylidene fluoride) composite membrane is prepared via electrospinning technology for safe lithium metal batteries. This membrane (45 μm) exhibits the high porosity (76.9 %) and excellent thermally stability (>180 °C) preventing the short circuit during abuse. The CA/PVDF-based gel polymer electrolyte (GPE), fabricated with CA/PVDF electrospun membrane swelled by carbonate-based organic liquid electrolyte, delivers the ionic conductivity of 1.82 mS cm−1 and Li + transfer number of 0.506, which achieve uniform Li+ ion electrodeposition and inhibit the formation of lithium dendrites. As the results, the symmetrical cell Li/CA/PVDF-based GPE/Li exhibits the impressive reversible Li stripping/plating behavior over 300 h at 1 mA cm−2 with the capacity of 1 mA h cm−2. Furthermore, the assembled LiFePO4/GPE/Li battery exhibits the capacity of 101.2 mA h g−1 at 5C with the capacity retention of 94.6 % after 400 cycles, which exceeds that of traditional liquid electrolytes. This research provides a low-cost gel polymer electrolyte via the electrospinning technique for rechargeable lithium batteries with good electrochemical performance and high security.

Bridging dielectric-magnetic synergistic units with MOFs on fibers structure for high-efficient microwave absorption at low filler loading

Metal-organic framework (MOF) capable of magnetic-dielectric synergy loss mechanisms shine in the field of electromagnetic wave (EMW) absorption, whereas their high filler loading in the matrix remains a challenge and limit their practical application. Here, we mono-disperse bimetallic CoZn-MOF on conductive carbon nanofibers precursor via electrospinning technique and a following heat-treatment was employed to construct a Co–ZnO@NC carbon nanofiber (CNF) composites. The Co–ZnO particles with a size of 2 μm are evenly distributed within the carbon fibers, forming a unique structure resembling a “pearl necklace”. The introduction of one-dimension (1D) CNF can prolong the electron transport path and effectively reduces the percolation threshold of the composites. The composites are endowed with abundant heterogeneous interfaces, excellent magnetic-dielectric synergy and improved impedance matching, benefiting from which the obtained Co–ZnO@NC CNF composites demonstrate a maximum reflection loss (RLmin) of −54.5 dB at a thickness of 2.3 mm and an effective absorption bandwidth (EAB) of 8.12 GHz at a filler loading of merely 10 %. This study provides a feasible strategy for the design of MOF-derived absorbers with enhanced microwave absorption capacity at low filler loading.

Exploration of multi-layered nanofiber adjuvant implants of doxorubicin and resveratrol to prevent post-surgery tumor recurrence and invasion

Tumor-free survival post-surgical ablation is not durable due to tumor recurrence and metastasis in breast cancer patients. Studies have reported that trauma-prone sites are most vulnerable to the seeding of disseminated tumor cells (DTC) and ultimately tumor recurrence. We have developed Doxorubicin (DOX) and Resveratrol (RES) loaded nanofibers (NFs) to be used as adjuvant implants after surgical removal of the breast tumor. The electrospinning technique was employed to develop the NFs. Cell line evaluations showed synergistic activity of the drug combination on the MDA-MB-231 metastatic cell line. The cell cycle analysis revealed that the DOX and RES arrested the cell cycle in the G2/M and G0/G1 phases, respectively. The scratch assay exhibited that the co-delivery of RES prevented the invasive potential of the MDA-MB-231 cell line. The sustained nature of drug release from the NFs decreased DOX-induced necrotic cell death. The co-delivery of RES and DOX promoted apoptotic cell death in the MDA-MB-231 cell line. Thus, we conclude that the DOX and RES-loaded NFs can be employed as post-surgery adjuvant implants to check tumor recurrence and metastasis.

Antibacterial and Osteogenic Dual-Functional Micronano Composite Scaffold Fabricated via Melt Electrowriting and Solution Electrospinning for Bone Tissue Engineering.

The utilization of micronano composite scaffolds has been extensively demonstrated to confer the superior advantages in bone repair compared to single nano- or micron-sized scaffolds. Nevertheless, the enhancement of bioactivities within these composite scaffolds remains challenging. In this study, we propose a novel approach to combine melt electrowriting (MEW) and solution electrospinning (SES) techniques for the fabrication of a composite scaffold incorporating hydroxyapatite (HAP), an osteogenic component, and roxithromycin (ROX), an antibacterial active component. Scanning electron microscopy (SEM) and Fourier-transform infrared spectroscopy (FTIR) confirmed the hierarchical architecture of the nanofiber-microgrid within the scaffold, as well as the successful loading of HAP and ROX. The incorporation of HAP enhanced the water absorption capacity of the composite scaffold, thus promoting cell adhesion and proliferation, as well as osteogenic differentiation. Furthermore, ROX resulted in effective antibacterial capability without any observable cytotoxicity. Finally, the scaffolds were applied to a rat calvarial defect model, and the results demonstrated that the 20% HAP group exhibited superior new bone formation without causing adverse reactions. Therefore, our findings present a promising strategy for designing and fabricating bioactive scaffolds for bone regeneration.