Solution Blow Spinning Research Articles

Improved Antibacterial Properties of Polylactic Acid-Based Nanofibers Loaded with ZnO-Ag Nanoparticles through Pore Engineering.

In the post-epidemic era, bio-based protective fiber materials with active protective functions are of utmost importance, not only to combat the spread of pathogens but also to reduce the environmental impact of petroleum-based protective materials. Here, efficient antibacterial polylactic acid-based (PLA-based) fibers are prepared by solution blow spinning and their pore structures are regulated by controlling the ratio of the solvent components in the spinning solutions. The porous PLA-based fibers exhibit antibacterial efficiencies of over 99% against Escherichia coli and over 98% against Bacillus subtilis, which are significantly higher than that of the nonporous PLA-based fibers. The excellent antibacterial property of the porous PLA-based fibers can be attributed to their high porosity, which allows antibacterial nanoparticles to be released more easily from the fibers, thus effectively killing pathogenic microorganisms. Moreover, pore structure regulation can also enhance the mechanical property of the PLA-based fiber materials. Our approach of regulating the microstructure and properties of the PLA-based fibers through pore engineering can be extended to other polymer fiber materials and is suitable for polymer-based composite systems that require optimal performance through sufficient exposure of doped materials.

PVA/zein nanofibers obtained by solution blow spinning

PVA/zein nanofibers obtained by solution blow spinning

Solution Blow-Spun Poly (Ethylene Oxide)-Polysulfone Bicomponent Fibers-Characterization of Morphology, Structure, and Properties.

Solution blow spinning was used to prepare nonwoven bicomponent fibers constituted by poly (ethylene oxide)-Polysulfone (PEO-PSF). As a new material, deep characterization was carried out to have a database to understand final performance regarding its multiple functions as a potential material for biomedical applications. The morphology was studied by field emission scanning electron and transmission electron microscopy and optical profilometry. Structural characterization was carried out by Fourier transform infrared spectroscopy and thermal degradation by thermogravimetric analysis. Additionally, wettability and mechanical behavior were studied by contact angle measurements and tensile tests, respectively. The bicomponent material was constituted of fibers with a structure mainly described by a core-shell structure, where the PSF phase is located at the center of the fibers, and the PEO phase is mainly located at the outer parts of the fibers, leading to a kind of shell wall. The study of possible interactions between different phases revealed them to be lacking, pointing to the presence of an interface core/shell more than an interphase. The morphology and roughness of the bicomponent material improved its wettability when glycerol was tested. Indeed, its mechanical properties were enhanced due to the PSF core provided as reinforcement material.

Multifunctional bilayer membranes composed of poly(lactic acid), beta-chitin whiskers and silver nanoparticles for wound dressing applications

Nanomaterial-based wound dressings have been extensively studied for the treatment of both minor and life-threatening tissue injuries. These wound dressings must possess several crucial characteristics, such as tissue compatibility, non-toxicity, appropriate biodegradability to facilitate wound healing, effective antibacterial activity to prevent infection, and adequate physical and mechanical strength to withstand repetitive dynamic forces that could potentially disrupt the healing process. Nevertheless, the development of nanostructured wound dressings that incorporate various functional micro- and nanomaterials in distinct architectures, each serving specific purposes, presents significant challenges. In this study, we successfully developed a novel multifunctional wound dressing based on poly(lactic acid) (PLA) fibrous membranes produced by solution-blow spinning (SBS) and electrospinning. The PLA-based membranes underwent surface modifications aimed at tailoring their properties for utilization as effective wound dressing platforms. Initially, beta-chitin whiskers were deposited onto the membrane surface through filtration, imparting hydrophilic character. Afterward, silver nanoparticles (AgNPs) were incorporated onto the beta-chitin layer using a spray deposition method, resulting in platforms with antimicrobial properties against both Staphylococcus aureus and Escherichia coli. Cytotoxicity studies demonstrated the biocompatibility of the membranes with the neonatal human dermal fibroblast (HDFn) cell line. Moreover, bilayer membranes exhibited a high surface area and porosity (> 80%), remarkable stability in aqueous media, and favorable mechanical properties, making them promising candidates for application as multifunctional wound dressings.

Active Cellulose Acetate/Chitosan Composite Films Prepared Using Solution Blow Spinning: Structure and Electrokinetic Properties.

Cellulose acetate (CA), a very promising derivative of cellulose, has come into the focus of research due to its highly desired good film-forming ability for food packaging applications. Frequently, this derivative is used in combination with other compounds (polymers, nanoparticles) in order to obtain active materials. Here, we report the preparation of thin films made of cellulose acetate loaded with chitosan (CS) using the solution blow spinning (SBS) method. Films are prepared by SBS processing of the polymers mixture solution, considering the following variables: (i) the concentration of cellulose acetate and chitosan in the solution and (ii) the solvent system consisting of acetic or formic acid. The prepared materials are characterized in terms of physical properties, roughness (optical profilometer), porosity, wettability (contact angle measurements), chemical structure (Fourier transform infrared spectrometry), and electrokinetic properties (zeta potential). SBS enables the preparation of CA/CS films with high water vapor permeability, high porosity, and also higher water contact angle compared with pure CA films. The electrokinetic properties of composites are influenced by the inclusion of chitosan, which causes a shift of the isoelectric point (IEP) towards higher pH values, but the magnitude of the shift is not in correlation with chitosan concentration. Adsorption kinetic studies using bovine serum albumin (BSA) as a model protein reveal that chitosan modified cellulose acetate films manifest low affinity towards proteins that suggests prevention of biofilm formation on its surface.

Soy Protein Nanofibers Obtained by Solution Blow Spinning

The climate crisis, growing pollution of the environment with waste, and ubiquitous microplastics have encouraged the search for new methods and new opportunities to use natural materials in the least harmful processes. Replacing synthetic materials with raw materials is not only a matter of “fashion”, but also a necessity. Therefore, this study aimed to produce fibers from an aqueous solution containing the highest possible concentration of soy protein isolate (SPI) through solution-blowing. As the aqueous solution of SPI has no fiber-forming potential, polyethylene oxide (PEO) was used as the carrier/matrix. The rheology of the aqueous PEO solution and PEO/SPI blends (flow curves, loss modulus, and storage modulus) was then analyzed. The proportions of the PEO/SPI mixtures and the process parameters were determined on this basis. As a result of the conducted research, nanofibers were produced from water solutions of PEO/SPI with a soy protein content of up to 7.88%, with a PEO share of 1.25%. The average diameter of the obtained fibers was 225–495 nm, depending on the process parameters and SPI content—as the SPI content in the PEO/SPI mixture increased, the average fiber diameter decreased. The production of nanofibers with a high soy protein content increases their application possibilities. Firstly, due to a much larger surface area, and secondly, due to the presence of numerous functional groups in the protein structure, which can be a place of attachment for additional compounds that give the obtained nanofibers the desired properties.

Curcumin-loaded polycaprolactone/carboxymethyl chitosan nanofibers with photodynamic inactivation of Staphylococcus aureus developed by solution blow spinning

The purpose of the present study was to utilize solution blow spinning to fabricate curcumin (CUR)-loaded polycaprolactone (PCL)/carboxymethyl chitosan (CMCH) nanofibers with photodynamic inactivation activity for inactivation of S. aureus. The results of ATR-FTIR and XRD spectra demonstrated the successful encapsulation of CUR without disrupting the structure of the nanofibers and increasing the crystallinity of the nanofibers. After the encapsulation of CUR, the thermal stability, tensile strength, and hydrophobicity of the PCL/CMCH nanofibers were improved. Besides, the CUR-loaded PCL/CMCH nanofibers possessed good biocompatibility and low toxicity, and could release CUR sustainably over 120 h. Moreover, the obtained nanofibers showed better inhibition of S. aureus under blue light irradiation at a wavelength of 450 nm compared to the no-light condition. The above results suggested that the developed nanofibers with photodynamic inactivation can be applied as food packaging materials to reduce the impact of S. aureus on human wellness.

Alumina Ceramic Nanofibers: An Overview of the Spinning Gel Preparation, Manufacturing Process, and Application.

As an important inorganic material, alumina ceramic nanofibers have attracted more and more attention because of their excellent thermal stability, high melting point, low thermal conductivity, and good chemical stability. In this paper, the preparation conditions for alumina spinning gel, such as the experimental raw materials, spin finish aid, aging time, and so on, are briefly introduced. Then, various methods for preparing the alumina ceramic nanofibers are described, such as electrospinning, solution blow spinning, centrifugal spinning, and some other preparation processes. In addition, the application of alumina ceramic nanofibers in thermal insulation, high-temperature filtration, catalysis, energy storage, water restoration, sound absorption, bioengineering, and other fields are described. The wide application prospect of alumina ceramic nanofibers highlights its potential as an advanced functional material with various applications. This paper aims to provide readers with valuable insights into the design of alumina ceramic nanofibers and to explore their potential applications, contributing to the advancement of various technologies in the fields of energy, environment, and materials science.

Fast Fabrication of Multifunctional PCL/Curcumin Nanofibrous Membranes for Wound Dressings.

Therapeutic intervention to skin wounds requires covering the affected area with wound dressings. Interdisciplinary efforts have focused on the development of smart bandages that can perform multiple functions. In this direction, here, we designed a low cost (U$0.012 per cm2) multifunctional therapeutic wound dressing fabricated by loading curcumin (CC) into poly(ϵ-caprolactone) (PCL) nanofibers using solution blow spinning (SBS). The freestanding PCL/CC bandages were characterized by distinct physicochemical approaches and were successful in performing varied functions, including controlled release of CC, colorimetric indication of the wound conditions, barrier against microorganisms, being biocompatible, and providing a photosensitive platform for antimicrobial photodynamic therapy (aPDT). The chemical nature of PCL and CC and the interactions between these components allowed CC to be released for 192 h (ca. 8 days), which could be correlated with the Korsmeyer-Peppas model, with a burst release suitable to treat the inflammatory phase. Due to the CC keto-enol tautomerism, an optical indication of the healing status could be obtained using PCL/CC, which occurred immediately, ranging between red/orange and yellow shades. The effect against pathogenic microorganisms evaluated by agar disc-diffusion, affected skin wound simulation (ex vivo), and microbial penetration tests demonstrated the ability to block and inhibit microbial permeation in different environments. The biocompatibilities of PCL and PCL/CC were verified by in vitro cytotoxicity study, which demonstrated that cell viabilities average above 94 and 96% for human dermal fibroblasts. In addition, the proposed bandage responded to aPDT applied to an in vivo assay, showing that, when irritated, PCL/CC was able to reduce the bacteria present on the real wound of mice. In summary, our findings demonstrate that using PCL and CC to produce nonwovens by the SBS technique offers potential for the rapid fabrication of biocompatible and multifunctional wound dressings, paving the way for large-scale production and utilization of such dressings in the treatment of skin wounds.

Preparation of photochromic solution blow spun polycarbonate nanofibers from recycled plastic for optical anticounterfeiting

In contrast to electrospinning, the newly developed solution blowing spinning (SBS) technology can produce nanofibers at high yield and low-cost without resorting to high voltage. It has been important to eliminate the pollution produced from polycarbonate plastic wastes. An intriguing method for enhancing the anticounterfeiting of numerous commercial goods is photochromism. It has been essential to enhance the engineering process of authentication materials in order to commence a transparent authentication nanocomposite. Herein, we present luminescent nanofibrous membranes prepared from strontium aluminate nanoparticles (SANPs)/recycled polycarbonate (PC) waste via SBS. The UV-motivated photochromic anticounterfeiting capability of the composite nanofibers was explored. For an enhanced dispersion without aggregation in the polycarbonate fibrous bulk, it is required to integrate SANPs in the nanostructure form in order to guarantee the translucent feature of SANPs@PC. Using different SANPs ratios provided different nanofibrous membranes with different emission properties. The morphology of SANPs was determined by X-ray diffraction (XRD) and transmission electron microscopy (TEM), which displayed diameters of 2–9 nm. The morphology, elemental contents, mechanical properties and optical transmittance of the SANPs@PC fibers were investigated using energy-dispersive X-ray (EDXA), X-ray fluorescence (XRF), and scanning electron microscopy (SEM). The diameters of SANPs@PC fibers were determined by SEM to be between 280 and 420 nm. An excitation peak (374 nm) and an emission peak (517 nm) were monitored in the SANPs@PC nanofibrous membranes. With the increased SANPs content, the contact angles of the SANPs@PC nanofibrous membranes were found to increase from 143.7° to 155.7°, indicating better superhydrophobicity. The colorless fibers displayed a quick and reversible photochromism to green without becoming fatigued when placed under UV supply. The current anticounterfeiting nanofibrous membranes can be described as a straightforward and efficient method of developing adaptable materials to provide a perfect market with financial and social profits at a low price.

71 A Novel Solution-Blow-Spinning Device Co-Sprays Autologous Skin Cell Suspensions and Polymer for Full Thickness Wounds

Abstract Introduction Autologous skin cell suspensions (ASCS) are useful for treating burn wounds, including in adjunct with split thickness skin grafts (STSG) for full thickness injuries. Careful wound care is crucial after ASCS application to prevent leakage out of the wound bed. Solution blow spinning (SBS) can be used to spray polymer fiber mats with varied flexibility, adhesion, and absorption. Wounds treated with ASCS and SBS dressings demonstrate equivalent re-epithelialization as those treated conventionally. SBS polymers are currently applied using commercial airbrushes with limited control of sterility, pressure, and deposition rate, and have only been evaluated when applied after ASCS. This work investigates a novel SBS prototype designed to address these limitations and simultaneously spray cells and dressings. Methods A SBS prototype was engineered combining a 3D printed, biocompatible, disposable dual-chambered nozzle, a reusable handheld module with programmable motorized actuators, and a pressure gauge connected to an external air source. The polymers poly(lactide-co-caprolactone) (PLCL), which exhibits excellent adhesion in moist environments, and poly(lactic-co-glycolic) acid (PLGA), which conforms to irregular surfaces as a protective layer, were chosen for initial testing. Six mm full-thickness punch biopsies were created on the dorsal aspect of C57/BL/6 mice and stented (Fig 1b). ASCS was prepared from donor mouse skin and viability was tested before and after spraying at 3, 10, and 30 PSI. Wounds were dressed with either conventional transparent film adhesive dressing (Fig 1c), polymers sprayed using the device, ASCS+polymers sprayed using the device (1e), or ASCS+polymers sprayed using an airbrush (1f). Wounds were harvested on postoperative day 5, formalin fixed and paraffin embedded. Six µm sections were stained with hematoxylin and eosin (H&E), imaged (Fig 2a). Epithelial tongue length was measured by a blinded assessor. Results ASCS cell viability was 47.3±8.3% at baseline and was only significantly decreased after spraying at 30 PSI (12.2±11.0%). Hence, 10 PSI was used for the mouse experiment (Fig 2b). Overall, there were no significant differences in epithelial tongue length between the wounds treated with different cell and polymer-based dressings (Fig 2c). Conclusions The SBS prototype can be used to spray ASCS at pressures up to 10 PSI without significant loss of viability. The novel device was able to co-spray ASCS and polymers onto a wound bed. Wounds dressed with SBS polymers demonstrate equivalent epithelial tongue length at post-wound day 5 compared with wounds treated with transparent film dressing and airbrush controls. Applicability of Research to Practice Currently, ASCS and dressing application are performed in a stepwise fashion, which allows the ASCS to leak out of the wound bed. A simultaneous application process could limit ASCS loss, streamline the wound care procedure and improve healing outcomes.

Advanced TPU/ZnS:Al Flexible Film with Thermo-Force-Optical Response for Smart Clothing

With the continuous development of science and technology, smart sensing wearables have gradually entered people’s lives. However, the prepared wearable material has poor air permeability, poor fit, and does not have multiple modal excitations. In addition, it is not waterproof or even wearable at low temperatures. In this work, a thermoplastic polyurethane (TPU) and ZnS:Al composite film with excellent air permeability has been developed. The TPU/ZnS:Al flexible film can be prepared on a large scale by solution blow spinning (SBS). This fiber membrane can realize the dual response of temperature and stress, and cooperate with the light sensor to realize the transmission of intelligent information. This nanofiber membrane doped with ZnS:Al exhibits a uniform distribution, maintains excellent tensile properties and flexibility, and can adapt to any perfect shape of the fitting surface. Even the average air permeability can be as high as 300 mm s−1, which is 600 times that of conventional spraying methods. The Al introduced in ZnS:Al can stimulate the composite film to emit light, and the luminescence effect can be maintained for about 1 min. These results provide new ideas for the large-scale fabrication of integrated stimulus-responsive photosensitive intelligent wearable devices for various applications.

Novel synthesis of BCP cotton-wool-like nanofibrous scaffolds by air-heated solution blow spinning (A-HSBS) technique

Biphasic calcium phosphate (BCP) cotton-wool-like nanofibrous scaffolds are very interesting materials for tissue engineering. Air-heated solution blow spinning (A-HSBS) was a simple and novel strategy developed in this work to obtain this structure. Precursor solutions of calcium nitrate, triethyl phosphate, and polyvinylpyrrolidone (spinning agent) dissolved in water and ethanol were used. The scaffolds were calcined at 800 °C. Part of the samples was stored under restricted atmospheric conditions, while the other part was exposed to ambient conditions for 7 days. The scaffolds were characterized by thermogravimetric analysis, X-ray diffraction, Fourier transform infrared spectroscopy, and scanning electron microscopy. In vitro assays were performed using simulated body fluid (SBF) and phosphate-buffered saline (PBS) solutions. Results showed the formation of scaffolds constituted by intertwined nanometric fibers. XRD patterns indicated the formation of BCP and CaO. For the sample exposed to air, CaCO3 was formed from the conversion of CaO with atmospheric CO2, producing BCP/CaCO3. After 7 days of immersion in SBF solution, the formation of a homogeneous layer of apatite was more evident on the surface of the BCP/CaCO3 than on the BCP nanofibers. The biodegradability in PBS medium, after 14 days of immersion, showed a mass loss of 21% (pH of 8.3) and 14% for the BCP and BCP/CaCO3 scaffolds (pH of 7.8), respectively. BCP nanofibrous scaffolds can be considered promising candidates for use in bone tissue engineering applications.

Multilevel structured PA66@BN nanofiber filter prepared via solution blow spinning and spraying for efficient particulate matter removal

AbstractAir pollution is currently a huge threat to human health, which leads to heavy demand for efficient air filters. Herein, this work reports a facile and scalable strategy to fabricate a multilevel structure PA66@BN air filter to remove fine particles by combination solution blow spinning (SBS) and spraying. In this study, the composite membrane contains three structural features at multiscale: 1D polyamide 66 (PA66), 2D large surface area boron nitride nanosheets (BN), and 3D interconnecting network structure fiber membranes. The filtration efficiency of the composite membrane for PM2.5 and PM10 is >95%, the pressure drop is only 53 Pa, and the removal rate of 0.3 μm ultrafine particles also can reach 90%, which realizes the characteristics of high efficiency and low resistance of high‐quality filter. The presence of large transverse size BN increases the specific surface area and roughness of the nanofibers, reduces the probability of particle reflection and escape, and enhances the mechanical interception effect of the nanofibers on PM, while preserving the complex porous structure of 3D interconnection. Therefore, this study provides an economical and low‐energy consumption new strategy for fabricating air filters with special forms to cope with the increasingly serious air pollution.

Nanofibrous Polymeric Membranes for Air Filtration Application: A Review of Progress after the COVID‐19 Pandemic

AbstractAir pollution is one of the major global problems causing around 7 million dead per year. In fact, a connection between infectious disease transmission, including COVID‐19, and air pollution has been proved: COVID‐19 consequences on human health are found to be more severe in areas characterized by high levels of particulate matter (PM). Therefore, after the COVID‐19 pandemic, the production of air filtration devices with high filtration efficiency has gained more and more attention. Herein, a review of the post‐COVID‐19 pandemic progress in nanofibrous polymeric membranes for air filtration is provided. First, a brief discussion on the different types of filtration mechanism and the key parameters of air filtration is proposed. The materials recently used for the production of nanofibrous filter membranes are presented, distinguishing between non‐biodegradable polymeric materials and biodegradable ones. Subsequently, production technique proposed for the fabrication of nanofibrous membranes, i.e., electrospinning and solution blow spinning, are presented aiming to analyze and compare filtration efficiency, pressure drop, reusability and durability of the different polymeric system processed with different techniques. Finally, present challenges and future perspectives of nanofibrous polymeric membranes for air filtration are discussed with a particular emphasis on strategies to produce greener and more performant devices.

Flexible piezoelectric PVDF/TPU nanofibrous membranes produced by solution blow spinning

Poly (vinylidene fluoride) (PVDF) nanofibers have been applied in producing piezoelectric membranes for energy harvesting in wearable devices under strenuous service conditions due to its outstanding properties such as piezoelectricity, flexibility, stability, and biocompatibility. Therefore, a processing technique with mass production capability and generating the highest possible piezoelectric properties of PVDF nanofibers is required. To achieve such requirements, this study presented a novel flexible piezoelectric membrane based on PVDF/TPU nanofibers using solution blow spinning (SBS). The addition of TPU into PVDF has been proven to increase the flexibility of the polymeric membranes. The produced membranes showed high piezoelectric response and sensitivity compared to other PVDF-based membranes in the literature especially at 5wt.% TPU concentration, owing to its small nanofiber diameter, high β fraction, and inducing reorientation of electric dipoles. The addition of TPU also significantly enhanced tensile strength and elasticity of the produced membranes. Based on those, this work has shown a promising method to produce high elastic-piezoelectric nanofibrous membrane using SBS.

Effect of chemically modified lignin addition on the physicochemical properties of PCL nanofibers

In this study, a chemically modified lignin additive was successfully prepared to improve the physicochemical properties of biodegradable polycaprolactone (PCL)-based nanofibers. The molecular weight and surface functional group characteristics of lignin were effectively controlled through a solvent fractionation process using ethanol. Then, PCL-g-lignin was successfully synthesized by using ethanol-fractionated lignin as a platform for the PCL grafting process. Finally, PCL/PCL-g-lignin composite nanofibers were simply prepared by adding PCL-g-lignin to the PCL doping solution and performing a solution blow spinning process. The addition of PCL-g-lignin could dramatically improve the physical and chemical properties of PCL nanofibers, and in particular, the tensile strength (0.28 MPa) increased by approximately 280 % compared to the conventional PCL. In addition, the lignin moiety present in PCL-g-lignin was able to impart UV blocking properties to PCL nanofibers, and as a result, it was possible to effectively suppress the photolysis phenomenon that occurred rapidly in existing PCL nanofibers. Therefore, PCL-g-lignin may be widely used not only as a reinforcing agent of existing biodegradable nanofibers but also as a functional additive for UV protection.

Fabrication and magnetic properties of SiO2 nanoparticles-doped BSCCO superconducting nanofibers by solution blow spinning

In this work, the magnetic properties of Bi2Sr2CaCu2O8+θ (BSCCO) superconducting nanofibers prepared by solution blow spinning technology were studied systematically. The BSCCO superconductors were doped with SiO2 nanoparticles in order to study the influence of non-superconducting impurities on the microstructure and magnetic properties of superconductors. The results showed that 0.2 wt% SiO2 nanoparticles can improve superconducting performance as efficient magnetic flux pinning centers in BSCCO superconductors. For examples the superconducting transition temperature was increased from 76.5 K to 80.3 K, the critical current density was increased from 0.68 × 108 A m−2 to 1.43 × 108 A m−2, and the pinning strength was increased from 4.4 × 107 N m−3 to 8.1 × 107 N m−3. In addition, it was found that appropriate amount of SiO2 nanoparticles can improve the size of superconducting grains and enhance the connectivity of superconducting grains. Moreover, the pinning mechanism of each sample demonstrated that SiO2 nanoparticles improved the pinning performance of BSCCO. Furthermore, this is the first report on the BSCCO superconductors that doped with SiO2 nanoparticles.

Green preparation of electrically conductive solution blow spun nanofibers from recycled polyethylene terephthalate via plasma-assisted oxidation-reduction.

Simple and green strategy was described for the development of multifunctional polyester nanofibers (PNFs). Solution blow spinning (SBS) technology was applied to in situ immobilize nanocomposites of polyaniline (PANi) and silver nanoparticles (AgNPs) into plasma-treated polyester nanoscaled fibers prepared. The polyester nanofibers were prepared from recycled polyethylene terephthalate waste, which was exposed plasma-curing and a REDOX reaction in the presence of AgNO3, aniline, and CH3COONH4. Plasma-catalyzed oxidative polymerization of aniline to polyaniline together with a reductive process of Ag+ to silver nanoparticles led to their enduring insoluble dispersion into the surface of polyester nanofibers. By taking the advantage of the PANi oxidation, AgNPs were precipitated from an aqueous medium of AgNPs. The morphological properties were investigated by various analytical techniques. The polyester fiber diameter was determined in the range of 450-650nm. In addition, transmission electron microscopy (TEM) and scanning electron microscopy (SEM) were utilized to examine AgNPs, demonstrating diameters of 4-20nm. The plasma-uncured AgNPs/PANi immobilized nanofibrous film displayed weak absorption bands at 399nm and 403nm upon increasing the concentration of AgNPs. On the other hand, the plasma-cured AgNPs/PANi immobilized nanofibers displayed strong absorption bands at 526nm and 568nm upon increasing the concentration of AgNPs. The AgNP-induced antimicrobial performance and the PANi-induced electrically conductivity were explored. The prepared PNFs showed high UV protection.

Multilayered blow-spun vascular prostheses with luminal surfaces in Nano/Micro range: the influence on endothelial cell and platelet adhesion

BackgroundIn this study, two types of polyurethane-based cylindrical multilayered grafts with internal diameters ≤ 6 mm were produced by the solution blow spinning (SBS) method. The main aim was to create layered-wall prostheses differing in their luminal surface morphology. Changing the SBS process parameters, i.e. working distance, rotational speed, volume, and concentration of the polymer solution allowed to obtain structures with the required morphologies. The first type of prostheses, termed Nano, possessed nanofibrous luminal surface, and the second type, Micro, presented morphologically diverse luminal surface, with both solid and microfibrous areas.ResultsThe results of mechanical tests confirmed that designed prostheses had high flexibility (Young’s modulus value of about 2.5 MPa) and good tensile strength (maximum axial load value of about 60 N), which meet the requirements for vascular prostheses. The influence of the luminal surface morphology on platelet adhesion and the attachment of endothelial cells was investigated. Both surfaces did not cause hemolysis in contact with blood, the percentage of platelet-occupied area for Nano and Micro surfaces was comparable to reference polytetrafluoroethylene (PTFE) surface. However, the change in morphology of surface-adhered platelets between Nano and Micro surfaces was visible, which might suggest differences in their activation level. Endothelial coverage after 1, 3, and 7 days of culture on flat samples (2D model) was higher on Nano prostheses as compared with Micro scaffolds. However, this effect was not seen in 3D culture, where cylindrical prostheses were colonized using magnetic seeding method.ConclusionsWe conclude the produced scaffolds meet the material and mechanical requirements for vascular prostheses. However, changing the morphology without changing the chemical modification of the luminal surface is not sufficient to achieve the appropriate effectiveness of endothelialization in the 3D model.