Blend Electrospinning Research Articles

Inducing Cu2+ species to SrTiO3 nanofibers based on blend electrospinning for boosting CO2 photoreduction to CH3OH

Photocatalytic CO2 reduction presents a promising strategy to alleviate environmental issues caused by massive CO2 emissions. SrTiO3, a potential photocatalyst for photocatalytic CO2 reactions, is limited by poor photoresponsivity and fast photogenerated carrier recombination. In this work, a series of Cu2+ species modified SrTiO3 nanofibers (xCuO/STO) was prepared combining sol-gel method and electrospinning with different copper content. The CH3OH yield of the 0.08CuO/STO photocatalyst reached up to 5.75 ± 0.27 μmol g−1 h−1, which was 2.2 times higher than that of pure SrTiO3. It was attributed that the blend electrospinning promoted Cu2+ species to be well dispersed on the surface of the SrTiO3 nanofibers. The strategy effectively enhanced the light absorption of the photocatalyst and inhibited the recombination of the photogenerated carriers. Part of appropriate characterizations were employed to elucidate the above point. In addition, to explore the inherent mechanism between the two species, the Density Functional Theory (DFT) calculations were further applied in the inherent mechanism between the species. This work provided a blend electrospinning approach for designing cocatalyst-modified SrTiO3 nanofibers for photocatalytic reduction of CO2.

Fabrication and characterization of Ecklonia cava phlorotannin‐loaded PVA/PVP blend electrospun nanofibers as a potential diabetic wound dressing biomaterial

AbstractDiabetic wound healing remains a challenging issue, necessitating advanced dressings with active therapeutic agents to reduce inflammation and promote healing. Ecklonia cava phlorotannin (ECP) possesses therapeutic potential for wound healing including anti‐microbial, antioxidant, and anti‐inflammatory properties. Our previous study demonstrates the therapeutic efficacy of ECP‐loaded nanofibers in an in vitro hyperglycemic wound model. The present paper focuses on the detailed characterization of the polyvinyl alcohol (PVA)/polyvinylpyrrolidone (PVP) blend nanofiber incorporated with ECP. The ideal ratio, PVA80:PVP20, is selected to incorporate with ECP via the blend electrospinning method. To confirm the successful loading of ECP (0.5% and 1%), physicochemical characterization is conducted using scanning electron microscopy, Fourier‐transform infrared spectroscopy, and thermal analysis. Functionality assays are performed to evaluate their applicability as dressing biomaterials. Physicochemical analyses confirm the successful loading of ECP into the nanofibers. Overall, the ECP‐loaded PVA/PVP nanofiber membranes exhibit favorable wound dressing criteria, which attributed to high water absorption capacity (200%–400%), sufficient water vapor transmission rate (1550–1650 g/m2/d), high loading efficiency and slow release. Bioactivity tests indicate that the ECP's effectiveness is unaffected by the electrospinning process. Importantly, these membranes exhibit biocompatibility and nontoxicity to human dermal fibroblasts, indicating their potential as good diabetic wound dressings.

Robust superhydrophobic Fe3O4/PAN/PBA nanofibrous aerogel with photo/magneto-thermal properties for efficient all-weather cleanup of viscous crude oil spills

Developing efficient absorbents for the cleanup of highly viscous crude oil spills is of critical importance. The current light-to-heat/electric-to-heat methods to reduce the viscosity of crude oil were limited by the complicated preparationprocesses, weather conditions and potential risk of electrical leakage. Here, a robust superhydrophobic composite Fe3O4/PAN/PBA nanofibrous aerogel (NFA) with excellent photo/magneto-thermal performance for efficient all-weather viscous crude oil spill remediation was fabricated by integrating facile blend electrospinning and freeze-drying techniques. Due to its superhydrophobicity/superoleophilicity (water contact angle of 151.3° and oil contact angle of 0°) and anisotropic microchannelstructure, the composite NFA exhibited rapid adsorption kinetics and ultra-high absorption capacity (54.4 − 97.1 g/g) toward various low-viscosity oils and organic solvents. Meanwhile, it displayed outstanding mechanical recyclability (84.07 % recovery after 200 cycles at 80 % strain) and reusability (86.74 % of theinitial capacity after 10 absorption-squeezing cycles). Notably, the composite NFA also showed excellent photo/magneto-thermal conversion efficiency, allowing it to achieve continuous and efficient cleanup ofcrude oil (recovery rate of 6.67 x103 kg m−3h−1) via peristaltic pumping. Therefore, this material holds great potential for all-weather cleanup of crude oil spills.

Exploring temperature-responsive drug delivery with biocompatible fatty acids as phase change materials in ethyl cellulose nanofibers

This study introduces a novel temperature-responsive drug delivery system using ethyl cellulose (EC) nanofibers encapsulating a eutectic mixture of lauric acid/stearic acid (LA/SA) as phase change materials (PCMs) and Rhodamine B (RhB) as a model drug. Employing blend electrospinning, the nanofibers achieved controlled drug release responsive to temperature changes. The peak shift of the carbonyl group in FTIR analysis confirmed drug-polymer compatibility, while the absence of RhB peaks in the XRD and DSC assessments revealed RhB's amorphous distribution within the fibers. Our findings demonstrate that RhB release is dependent on its loading, with a slow initial release (<2 %) for 1 % and 5 % RhB loadings and a burst release (~12 %) for 10 % loading. Notably, the release rate was tunable at 37 °C by adjusting LA/SA concentration. The optimal LA/SA loading for temperature-responsive release is identified as 10 %. Over 240 h, there is a 32 % increase in RhB release at 37 °C, and an additional 8 % increase at 40 °C, compared to 25 °C. This research illustrates the potential of PCM-integrated nanofibers in smart drug delivery, particularly for chemotherapy, antibiotics, and anti-inflammatory drugs, showcasing an innovative approach to improving therapeutic efficiency while reducing side effects.

Temozolomide nano-in-nanofiber delivery system with sustained release and enhanced cellular uptake by U87MG cells

Objective The study was aimed at formulating temozolomide (TMZ) loaded gelatin nanoparticles (GNPs) encapsulated into polyvinyl alcohol (PVA) nanofibers (TMZ–GNPs–PVA NFs) as the nano-in-nanofiber delivery system. The secondary objective was to explore the sustained releasing ability of this system and to assess its enhanced cellular uptake against U87MG glioma cells in vitro. Significance Nano-in-nanofibers are the emerging drug delivery systems for treating a wide range of diseases including cancers as they overcome the challenges experienced by nanoparticles and nanofibers alone. Methods The drug-loaded GNPs were formulated by one-step desolvation method. The Design of Experiments (DoE) was used to optimize nanoparticle size and entrapment efficiency. The optimized drug-loaded nanoparticles were then encapsulated within nanofibers using blend electrospinning technique. The U87MG glioma cells were used to investigate the uptake of the formulation. Results A 32 factorial design was used to optimize the mean particle size (145.7 nm) and entrapment efficiency (87.6%) of the TMZ-loaded GNPs which were subsequently ingrained into PVA nanofibers by electrospinning technique. The delivery system achieved a sustained drug release for up to seven days (in vitro). The SEM results ensured that the expected nano-in-nanofiber delivery system was achieved. The uptake of TMZ–GNPs–PVA NFs by cells was increased by a factor of 1.964 compared to that of the pure drug. Conclusion The nano-in-nanofiber drug delivery system is a potentially useful therapeutic strategy for the management of glioblastoma multiforme.

Novel activated biochar-enhanced superhydrophilic nanofibrous membrane for superior oil-in-water emulsion separation

In this research, a high-performance Polyamide 6/Polyvinyl Alcohol/Activated biochar (PA6/PVA/AB) composite nanofibrous membrane was developed for effective separation of oil-in-water emulsions. The membrane was produced by blend electrospinning of Polyamide 6 (PA6), Polyvinyl Alcohol (PVA), and Activated biochar (AB) derived from peanut shell biomass. Glutaraldehyde (GA) cross-linking was applied to enhance stability in aqueous environments to prevent PVA swelling. The resulting nanofibrous membrane exhibited a cost-effective design with a superhydrophilic/underwater superoleophobic surface (WCA of 0° and UWOCA of 164°), a porous structure (93% porosity), and robust mechanical properties (Tensile strength: 7.73 MPa, Young modulus: 45 MPa). Optimization of the membrane composition, with 5%wt. PVA and 2%wt. AB relative to the total polymer weight in the electrospinning solution, yielded a superhydrophilic membrane capable of withstanding 2 bar pressure. Pure water flux measurements in the pressure range of 0.5–2 bar demonstrated a high permeability of 1727.5 LMH/bar and a pure water flux of 3455 LMH. The PA6/PVA/AB composite membrane exhibited exceptional performance in separating non-surfactant (NS) and surfactant-stabilized (SS) toluene-in-water emulsions (separation flux: 2006 LMH, oil rejection: 99.52%). Furthermore, it demonstrated high efficiency in the separation of SS oil-in-water emulsions of different types of oil (separation flux >1800 LMH, oil rejection >98%). The membrane's durability and chemical stability were confirmed through 15 cycles of oil-in-water emulsion separation, showcasing anti-fouling properties and reusability (separation flux >833, Oil rejection >97%). Considering its superior performance in oil-in-water emulsion separation and robust reusability, the developed nanofibrous membrane holds significant promise for practical applications.

Blend Electrospinning of Nigella sativa-Incorporating PCL/PLA/HA Fibers and Its Investigation for Bone Healing Applications.

One of the well-known postoperative complications that requires a number of prophylactic and curative treatments is infection. The implications of postsurgical infections are further exacerbated by the emergence of antibiotic-resistant strains. Reduced effectiveness of synthetic antibiotics has led to an interest in plant-based substances. Extracts obtained from Nigella sativa have been shown to possess effective anti-infectious agents against bacteria frequently seen in bone infections. In this study, a fiber-based bone scaffold containing polycaprolactone, poly(lactic acid), and hydroxyapatite with N. sativa oil at varying concentrations was developed. Solvent electrospinning was used to fabricate the fibers with the specified composition. According to FE-SEM analysis, fibers with average diameters of 751 ± 82, 1000 ± 100, 1020 ± 90, and 1223 ± 112 nm were formed and successful integration of N. sativa oil into the fiber's structure was confirmed via FTIR. Staphylococcus aureus showed moderate susceptibility against the fibers with a maximum inhibition zone diameter of 11.5 ± 1.6 mm. MTT assay analysis exhibited concentration-dependent cell toxicity against fibroblast cells. In short, the antibacterial fibers synthesized in this study possessed antibacterial properties while also allowing moderate accommodation of CDD fibroblast cells at low oil concentrations, which can be a potential application for bone healing and mitigating postsurgical infections.

(Invited) Monopolar and Bipolar Membranes Based on Nanofiber Electrospinning

Cation-exchange, anion-exchange, and bipolar membranes play crucial roles in a variety of electrochemical processes and devices, including chloralkali cells, electrodialysis separations for water purification, proton-exchange membrane and hydroxide-exchange membrane (alkaline) fuel cells, redox flow batteries, and processes for direct air capture of CO2. The incorporation of polymeric nanofibers into such membranes provides an attractive and tunable method of creating materials with new nano-morphologies and highly desirable properties.The impregnation of an ionomer solution into a pre-formed nonwoven porous mat of electrospun polymer fibers is a well-known method of making reinforced proton-exchange membranes. The use of simultaneous dual-fiber electrospinning or the electrospinning of polymer blends can be used to intermix/incorporate/co-locate dissimilar and incompatible polymers on the nanoscale. Although less studied in the literature, these methods offer many interesting possibilities for new membrane structures with targeted and unique transport and mechanical properties.In this review talk, the use of dual fiber and blended polymer fiber electrospinning for membrane fabrication will be presented for the following: (1) Nanofiber reinforced cation (proton) exchange membranes, (2) Electrospun NafionTM/PVDF dual fiber and single-fiber membranes for H2/Br2 redox flow batteries, (3) Composite anion exchange membranes, and (4) Bipolar membranes with a 3D nanofiber junction. Materials and methods for membrane fabrication will be described and the properties of the membranes will be discussed.

From Hemp Waste to Bioactive Nanofiber Composites: Deep Eutectic Solvents and Electrospinning in Upcycling Endeavors.

Natural fibers have attracted increasing interest as an alternative to produce environmentally friendly and sustainable materials. Particularly, hemp fibers have been widely used in various industrial applications due to their extremely unique properties. However, hemp can generate a large amount of agro-waste, and it results in an attractive source of biopolymers for the development of low-cost materials as an alternative to the raw materials and conventional petroleum-based plastics. In addition, deep eutectic solvents (DESs), a new type of truly green solvents, have been shown to remove gums, lignin, and other non-cellulosic components from hemp fibers. Reusing these components dissolved into the DESs to fabricate new materials directly by electrospinning is a very attractive but still unexplored endeavor. Thus, this innovative research to venture new upcycling pathways is focused on the fabrication of composite nanofibers by electrospinning of a gel-based blend of Poly(vinyl alcohol) (PVA) and hemp agro-waste (HW) dissolved into choline chloride (ChCl):Glycerol (1:2) and ChCl:Urea (1:2) DES mixtures. The results obtained revealed that the produced nanofibers displayed uniform appearance with diameters ranging from 257.7 ± 65.6 nm to 380.8 ± 134.0 nm. In addition, the mechanical properties of the electrospun composite nanofibers produced from the gel-based blends of HW dissolved in DESs and PVA (HW-DESs_PVA) were found to be superior, resulting in an enhanced tensile strength and Young's modulus. Furthermore, the incorporation of HW into the nanofibers was able to provide bioactive antioxidant and antibacterial properties. Overall, this study demonstrated a promising, more sustainable, and eco-friendly way to produce electrospun composite nanofibers using HW in a circular economy perspective.

Comparative study of drug release from electrospun nanofibers loaded with clotrimazole via two different approaches using a fully automated sequential injection system

The development of new drug delivery platforms including the use of nanotechnology has been found of great interest in recent years. Two different loading approaches of the model antimycotic drug clotrimazole into the nanofibrous polycaprolactone and polydioxanone structures including electrospinning of a drug-polymer blend and impregnation of nanofibers with drug have been tested. The final amount of clotrimazole in the nanofibrous materials was determined by HPLC analysis and Raman spectroscopy. The electrospinning of blend approach allowed the adsorption of clotrimazole in a quantity of up to 30 % using mixtures with polymer/clotrimazole ratios from 2:1 to 8:1 (w/w). Ethanolic clotrimazole solutions with concentrations from 2.5 to 3.5 mg L−1 were used for adsorbing clotrimazole in blank nanofibers for 1–3 h with final clotrimazole content ranging from 3.0 to 5.7 %. Furthermore, a comparative liberation study including comparison with commercially available creams was carried out in low pressure flow system. The results obtained confirmed well controlled release of clotrimazole from both types of nanofibers. Compared to commercial pharmaceutical formulations containing 1 % clotrimazole where first-order release kinetics was observed, nanofibrous materials provided linear controlled release (zero-order kinetics) in the tested 3 h period.

Development of ibuprofen-loaded electrospun materials suitable for surgical implantation in peripheral nerve injury

The development of nerve wraps for use in the repair of peripheral nerves has shown promise over recent years. A pharmacological effect to improve regeneration may be achieved by loading such materials with therapeutic agents, for example ibuprofen, a non-steroidal anti-inflammatory drug with neuroregenerative properties. In this study, four commercially available polymers (polylactic acid (PLA), polycaprolactone (PCL) and two co-polymers containing different ratios of PLA to PCL) were used to fabricate ibuprofen-loaded nerve wraps using blend electrospinning. In vitro surgical handling experiments identified a formulation containing a PLA/PCL 70/30 molar ratio co-polymer as the most suitable for in vivo implantation. In a rat model, ibuprofen released from electrospun materials significantly improved the rate of axonal growth and sensory recovery over a 21-day recovery period following a sciatic nerve crush. Furthermore, RT-qPCR analysis of nerve segments revealed that the anti-inflammatory and neurotrophic effects of ibuprofen may still be observed 21 days after implantation. This suggests that the formulation developed in this work could have potential to improve nerve regeneration in vivo.

Fabrication of novel electrospun zein/polyethylene oxide film incorporating nisin for antimicrobial packaging

The composite electrospun zein/polyethylene oxide (PEO) films were successfully fabricated by incorporating nisin at different levels using blending electrospinning for the first time. Electrospinning of zein/PEO solution conducted at optimized voltage of 15 kV with a flow rate of 3 mL/h and distance of 12 cm caused the formation of fibers with bead-free and uniform morphologies. The increased level of the incorporated nisin in zein/PEO fibers caused increasing conductivity and viscosity of solutions, which resulted in the smaller fiber diameter. Furthermore, the enhanced antibacterial activity and mechanical strength was detected with addition of nisin. The fourier transform infrared spectroscopy suggested that these biomolecules interacted with each other via hydrogen bonding. The zein/PEO packing films incorporated with nisin effectively inhibited the bacterial growth and retarded the chemical deterioration of chicken breast during 12-days storage at 4 °C. Therefore, electrospun zein/PEO loaded with nisin could be a prospective active packaging for food preservation.

Electrospun Polymeric Fibers Decorated with Silk Microcapsules via Encapsulation and Surface Immobilization for Drug Delivery.

Hollow polymer microcapsules as drug carriers have the advantages of drug protection, storage, and controlled release. Microcapsules combined with tissue engineering scaffolds such as electrospun microfibers can enhance long-term local drug retention. However, the combination methods of microcapsules and fibers still need to be further explored. Here, we developed different technical approaches to functionalize electrospun polycaprolactone (PCL) microfibers with silk fibroin (SF) microcapsules through encapsulation and surface immobilization, including direct blending and emulsion electrospinning for encapsulation, as well as covalent and cleavable disulfide-linkage for surface immobilization. The results of "blending" approach showed that silk microcapsules with different sizes could be uniformly encapsulated inside electrospun fibers without aggregation. To further reduce the use of organic solvents, the microcapsules in the aqueous phase can be uniformly distributed in the PCL organic phase and successfully electrospun into fibers using surfactant span-80. For surface immobilization, silk microcapsules were efficiently covalent binding to the surface of electrospun PCL fibers via click chemistry and exhibited noncytotoxic. Based on this method, with the incorporation of a disulfide bond, the linkages between microcapsule and fiber could be cleaved under reducing conditions. These microcapsule-electrospun fiber combination methods provide sufficient options for different drug delivery requirements. This article is protected by copyright. All rights reserved.

Correlation between the morphology of carbon nanofibers and the transport characteristics of Li-ions in a battery anode under fast charging conditions

Energy storage materials for electric vehicles and energy storage systems must be able to supply high capacity quickly, which requires efficient Li-ion transport within the anode active material. The transport of Li ions through a battery system can lead to concentration polarization and subsequent overpotential, which can limit the electrochemical performance, especially under fast charging conditions. To overcome these limitations, it is important to control solvated Li-ion transport and design an anode material with a rational approach. One way to achieve this is by controlling the morphology of carbon nanofibers (CNFs) to create ion transport channels. A facile method for this was investigated using an immiscible polymer blend electrospinning system and interpreting a ternary phase diagram. The effects of the morphology and space characteristics of each CNF on the electrochemical performance were studied, particularly the rate capability and cycle stability under fast charging conditions. These characteristics were analyzed in terms of the transport properties of the electrochemical species in different types of ion channels.

Electrospun heterojunction nanofibrous membranes for photoinduced enhancement of fine particulate matter capture in harsh environment

Particulate matter (PM) pollution has posed a severe threat to the environment and human health. Especially for submicron-level fine particulate PM0.3, it is still difficult to achieve high-efficiency filtration. Herein, we loaded TiO2/g-C3N4 (TCN) heterojunction photocatalyst on polystyrene/polyacrylonitrile (PS/PAN) multiscale nanofiber membranes by a simple one-step blending electrospinning technique. Due to the strong long-range electrostatic force of the built-in electric field, the composite membrane has a remarkably enhanced filtration effect under light. Even under harsh conditions with a high PM0.3 concentration of more than 1,800,000 m−3 and a high flow rate of 25 L/min, it still has a high filtration efficiency of greater than 98.5%, an increase of about 20% compared with dark conditions, and the pressure drop is only low to 94 Pa. More importantly, the electrostatic field can be regenerated with light, and this preparation strategy can be effectively extended to other photocatalyst heterojunctions.

A Sequential Electrospinning of a Coaxial and Blending Process for Creating Double-Layer Hybrid Films to Sense Glucose.

This study presents a glucose biosensor based on electrospun core-sheath nanofibers. Two types of film were fabricated using different electrospinning procedures. Film F1 was composed solely of core-sheath nanofibers fabricated using a modified coaxial electrospinning process. Film F2 was a double-layer hybrid film fabricated through a sequential electrospinning and blending process. The bottom layer of F2 comprised core-sheath nanofibers fabricated using a modified process, in which pure polymethacrylate type A (Eudragit L100) was used as the core section and water-soluble lignin (WSL) and phenol were loaded as the sheath section. The top layer of F2 contained glucose oxidase (GOx) and gold nanoparticles, which were distributed throughout the polyvinylpyrrolidone K90 (PVP K90) nanofibers through a single-fluid blending electrospinning process. The study investigated the sequential electrospinning process in detail. The experimental results demonstrated that the F2 hybrid film had a higher degradation efficiency of β-D-glucose than F1, reaching a maximum of over 70% after 12 h within the concentration range of 10-40 mmol/L. The hybrid film F2 is used for colorimetric sensing of β-D-glucose in the range of 1-15 mmol/L. The solution exhibited a color that deepened gradually with an increase in β-D-glucose concentration. Electrospinning is flexible in creating structures for bio-cascade reactions, and the double-layer hybrid film can provide a simple template for developing other sensing nanomaterials.

Temperature-Responsive Structurally Colored Fibers via Blend Electrospinning

Achieving fibers that change color with temperature may be promising for applications such as sensors and smart wearable textiles (woven and nonwoven). In this study, temperature-responsive cholesteryl ester liquid crystal formulations were blended with polycaprolactone or polystyrene using chloroform as a solvent for electrospinning to achieve thermochromic nonwoven products. Using polystyrene, beaded fibers were achieved and the thermochromic behavior was only observed under polarized light microscopy. To achieve fibers with visible thermochromic behavior observed by a video camera or smart phone, polycaprolactone was used as a carrier polymer. The comparison between polystyrene and polycaprolactone provides insight into polymer/solvent selection achieving responsive materials via blend processing. High loadings of liquid crystal were achieved with polycaprolactone, blends of 10 wt % polycaprolactone with 15 wt % liquid crystal formed fibers (fiber contained 60 wt % liquid crystal). Colored fibers could be achieved by varying the formulation of the liquid crystal. For example, liquid crystal formulations that were green at ambient conditions resulted in fibers that were green at ambient conditions (22 °C). Nonwoven fibers with dynamic color with temperature were also demonstrated. For example, liquid crystal formulations were colorless at ambient conditions and underwent a reversible color change from red to blue when heated and cooled between 32 and 37 °C. When incorporated into fibers, the fiber mats changed from white at ambient conditions to red at 32 °C to blue at 37 °C. The color change was reversible over multiple cycles.

Electrospun nanofibers using β-cyclodextrin grafted chitosan macromolecules loaded with indomethacin as an innovative drug delivery system

Electrospun nanofibers, as an innovative drug delivery system, provide selective, effective, and safe drug release. The present study aimed to fabricate nanofibers based on β-cyclodextrin grafted chitosan (β-CD-g-CS) macromolecules with incorporated drug via the blend electrospinning technique. The grafting of β-CD onto chitosan (CS) was confirmed by FT-IR, 1H NMR, TGA, XRD, and EDX analysis. Indomethacin was encapsulated in the β-CD-g-CS matrix as blend nanofibers using electrospinning in presence of polyvinyl alcohol (PVA). The SEM images revealed nanofibers with diameters at the nanoscale. The unique features of β-CD-g-CS/PVA as drug delivery system were investigated using indomethacin as a model drug molecule. Controlled release of indomethacin from nanofibers was studied in PBS solution by measuring the absorbance by UV–Vis spectrophotometer. The drug release profile exhibited that the rate of drug release can be tailored by polymer type and changing the drug/polymer ratio. The physicomechanical properties of the developed nanofibers were analyzed by tensile strength and water contact angle. The results demonstrated that β-CD-g-CS revealed enhanced wettability as well as favorable physicomechanical properties. In addition, the growth rate of the L929 cells on the CS and β-CD-g-CS nanofibers was not significantly inhibited and even improved cell proliferation. These findings indicated that β-CD-g-CS nanofibers could be appropriate as a smart drug delivery system for sustained release of indomethacin as an anti-inflammatory medicine in the wound healing and tissue engineering approaches in orthopedic applications.

Electrospun polycaprolactone nanofibers functionalized with Achillea millefolium extract yield biomaterial with antibacterial, antioxidant and improved mechanical properties.

In this study, polycaprolactone (PCL), as a biocompatible polymer was functionalized by addition of medicinal plant extract- Achillea millefolium L. (yarrow). Nanofiber mats were fabricated from PCL solutions containing dry yarrow extract in four concentrations (5%, 10%, 15%, and 20% relative to the weight of the polymer) by using blend electrospinning method. The nanofibers were characterized for their biological, mechanical and drug release behavior. In vitro release of yarrow polyphenols from the electrospun PCL nanofibers over a period of 5 days showed the release of up to 98% of the total loaded polyphenols. The released polyphenols retained its antioxidant activity, which was determined by DPPH assay. Electrospun PCL/yarrow nanofiber mats exhibited the antibacterial effect against Staphylococcus aureus, but had no effect on the growth of Pseudomonas aeruginosa. All PCL/yarrow nanofiber mats had improved mechanical properties compared to the neat PCL nanofibers, as evident by an increase in Young's modulus of elasticity (up to 5.7 times), the tensile strength (up to 5.5 times), and the strain at break (up to 1.45 times). Based on our results, yarrow-loaded PCL nanofiber mats appeared to be multi-functional biomaterials suitable for the production of catheter-coating materials, patches, or gauzes with antibacterial and antioxidant properties.

Quercetin- and Rutin-Containing Electrospun Cellulose Acetate and Polyethylene Glycol Fibers with Antioxidant and Anticancer Properties.

Innovative fibrous materials from cellulose derivative, cellulose acetate (CA) and water-soluble polyether, polyethylene glycol (PEG) loaded with natural biologically active compounds (BAC), quercetin (QUE) and rutin (RUT), have been successfully fabricated by blend electrospinning and dual electrospinning. Scanning electron microscopy revealed that the mean fiber diameters of all the obtained fibers were in the nanometer range. QUE and RUT incorporated in the fibrous mats were in the amorphous state, as evidenced by the performed differential scanning calorimetry (DSC) and X-ray diffraction (XRD) analysis. The presence of the polyether in the developed fibrous material assisted the in vitro release of the biologically active compounds by improving the hydrophilicity and wettability of the mats. Rutin-containing fibrous materials manifest the highest antioxidative activity, as determined by the 2,2-diphenyl-1-picryl-hydrazyl-hydrate free radical method. The cytotoxicity of the fabricated novel materials was evaluated using a tumor cell line and normal mouse fibroblast cells. The mats containing QUE and QUE/RUT independent of the applied spinning method show a higher cytotoxic effect against cancer cells and 3 to 4.5 times lower cytotoxicity to a noncancer cell line. These features make the quercetin- and rutin-containing fibrous materials promising candidates for pharmaceutical, cosmetic, and biomedical use.