Composite Nanofibrous Membranes Research Articles

Preparation of ZIF-8-coated polyacrylonitrile composite nanofibrous membrane for efficient oil-in-water emulsion separation

Preparation of ZIF-8-coated polyacrylonitrile composite nanofibrous membrane for efficient oil-in-water emulsion separation

Preparation and performance study of thermo-responsive P(NIPAM-AM-ABP)/keratin composite nanofiber membrane for bio-application

This paper describes a temperature-responsive composite nanofibrous membrane by blending of the P(NIPAM-AM-ABP) (PNAA) nanofiber and the wool keratin (WK) nanofiber. The photo crosslinkable PNAA with the LCST value of 38.1 °C was obtained by free radical copolymerization of the temperature sensitive N-Isopropylacrylamide (NIPAM) monomer, the hydrophilic monomer Acrylamide (AM), and the photo crosslinkable monomer 4-Acryloyloxybenzophenone (ABP). Keratin was extracted from waste wool fiber by reduction method. The PNAA nanofiber (PNAA-NF) and the keratin nanofiber (WK-NF) were electoral spun separately by two-needle parallel spinning, and the obtained composite nanofiber membrane was then crosslinked by UV irradiation and heat treatments to prepare the PNAA/WK nanofiber membrane (PNAA/WK-NFM) with good water tolerance. The result indicated that the photo cross-linkable temperature sensitive PNAA with the LCST of 38.1 °C was successfully synthesized. The obtained PNAA/WK-NFM has a good fibrous morphology and excellent water tolerance. The composite nanofiber membrane showed good reversible temperature sensitivity and temperature responsive drug releasing property due to the PNAA. By combining of the PNAA-NF and WK-NF, the mechanical property of the PNAA/WK-NFM was greatly enhanced in both dry and wet states, and the slow drug releasing property of the membrane was further improved. In-vitro cell culture experiments indicated that the PNAA/WK-NFM has a good biocompatibility with no cytotoxicity. These findings suggested that the PNAA/WK-NFM has a potential application in temperature responsive drug releasing biomaterials.

Enhanced X-ray shielding efficiency and visible light degradation performance of a multilayer composite protective material

To mitigate the adverse effects of high-energy radiation, such as X-rays, on patients during medical procedures, a multifunctional composite nanofibrous membrane has been engineered to shield against low-energy X-rays. This study involves integrating processed oil-tea camellia shells (OCS) powder into molten polylactic acid (PLA) for modification. Concurrently, metallic Bi is introduced to enhance Bi2WO6, which is subsequently combined with modified PLA and electrospun into nanofibrous membranes for photocatalytic antimicrobial and organic pollutant degradation. Additionally, sodium hyaluronate (NaHA) and a silver nanoparticle solution are electrospun with PLA to form a skin-friendly protective layer. Following this, a chitosan (CS) solution containing WO3 and B4C is used as a coating on the multilayered membranes. The membranes are then freeze-dried to create sandwich-structured multilayer composite protective material. This method addresses challenges associated with polylactic acid (PLA) in electrospinning and alleviates limitations such as low light absorption and slow charge transfer in Bi2WO6. Compared to similar materials, this composite material is lightweight, flexible for cutting, and exhibits strong X-ray shielding capabilities. The composite nanofibrous membrane demonstrates a shielding efficiency of 97.75 ± 2.05 % at low X-ray energy (46 kVp). Moreover, under visible light, the membrane generates reactive oxygen species, resulting in the efficient removal of 98.03 % of methylene blue (MB), 96.35 % of rhodamine B (Rh.B), and 91.51 % of methyl orange (MO) within 180 minutes. Furthermore, it displays bactericidal activity against E. coli and S. aureus under both dark and light conditions. In natural settings, the composite membrane undergoes gradual degradation in soil, completely decomposing within 28 days due to the influence of rainfall and microorganisms. Consequently, this composite membrane holds significant promise for specialized medical protective applications.

One-step fabrication of multifunctional TPU/TiO2/HDTMS nanofiber membrane with superhydrophobicity, UV-resistance, and self-cleaning properties for advanced outdoor protection

This study successfully fabricated thermoplastic polyurethane (TPU)-titanium dioxide (TiO2)-hexadecyltrimethoxysilane (HDTMS) composite nanofibrous membrane (CNM), exhibiting superhydrophobicity, robust UV resistance, and anti-fouling properties, via electrostatic spinning technology. The nanofibrous membranes' (NM) microstructures were meticulously characterized using techniques such as field emission scanning electron microscopy (FE-SEM), Fourier transform infrared spectroscopy (FTIR), Raman scattering spectroscopy, X-ray diffraction (XRD), X-ray photoelectron spectroscopy (XPS), and 3D optical profiling. Performance evaluations included water contact angle measurement, thermogravimetric analysis (TGA), differential scanning calorimetry (DSC), and uniaxial tensile and UV transmission tests. Results indicate that the CNM has an average fiber diameter of 179.28 nm, a static water contact angle (WCA) of 166.2 ± 0.5°, a sliding angle of 3.5 ± 0.8°, and a surface energy of 9.18 ± 0.6 mN/m. It also demonstrates commendable thermal stability with a tensile strength of 3.9 MPa, an elongation at break of 145.80 %, and an ultraviolet protection factor (UPF) of 1485 ± 13.2. It has considerable mechanical stability and can withstand 4000 tensile or 5000 compression cycles. The anti-fouling and moisture permeability tests reveal the membrane's superior functional performance. These attributes suggest a wide application potential for the CNM in anti-fouling outdoor protective clothing, sports footwear, and related fields.

MXene-coated piezoelectric poly-L-lactic acid membrane accelerates wound healing by biomimicking low-voltage electrical pulses

Electrical stimulation therapy is effective in promoting wound healing by rescuing the decreased endogenous electrical field, where self-powered and miniaturized devices such as nanogenerators become the emerging trends. While high-voltage and unidirectional electric field may pose thermal effect and damage to the skin, nanogenerators with lower voltages, pulsed or bidirectional currents, and less invasive electrodes are preferred. Herein, we construct a polydopamine (PDA)-modified poly-L-lactic acid (PLLA) /MXene (PDMP/MXene) nanofibrous composite membrane that generates piezoelectric voltages matching the transepithelial potential (TEP) to accelerate wound healing. PDA coating not only enhances the piezoelectricity of PLLA by dipole attraction and alignment, but also increases its hydrophilicity and facilitates subsequent MXene adhesion for electrical conductivity and stability in physiological environment. When applied as wound dressings in mice, the PDMP/MXene membranes act as a nanogenerators with reduced internal resistances and satisfactory piezoelectric performances that resemble bioelectric potentials (~10 mV) responding to physical activities. The membrane significantly accelerates wound closure by facilitating fibroblast migration, collagen deposition and angiogenesis, and suppressing the expression of inflammatory responses. This piezoelectric fibrous membrane therefore provides a convenient solution for speeding up wound healing by sustained low voltage mimicking bioelectricity, better cell affinity.

Superoleophobic polyethylene glycol grafted graphene oxide/polyamide 6 nanofibrous composite membrane for highly efficient separation of oil/water emulsion

Graphene oxide (GO) has been applied for membrane-based oil/water emulsion separation processes due to its ease of functionalization, substantial surface area, and abundant hydrophilic hydroxyl and carboxyl functional groups. In this study, the dispersion of GO in polyamide 6 (PA6) was improved through grafting of GO with polyethylene glycol (PEG). The prepared GO-PEG was integrated into PA6 nanofibers at different loading levels and the oil/water emulsion separation of the resulting PA6/GO-PEG membranes was compared as a function of GO-PEG content. The homogeneous dispersion of GO-PEG at a 2 wt% loading level within PA6 nanofibers (designated as PA6/GO-PEG2) resulted in a nanofibrous composite membrane that exhibited exceptional mechanical strength (approximately 16.29 MPa), and remarkable hydrophilic properties (water contact angle of 12.30°). Moreover, a remarkable underwater superoleophobicity was exhibited by PA6/GO-PEG2 and provided an underwater oil contact angle of 150.41°. Notably, the optimal characteristics were showcased by the PA6/GO-PEG2 nanofibrous membrane, offering an impressive water flux rate of 813 L/m2h and an outstanding oil rejection efficiency of 99.26 % when subjected to an oil/water emulsion under a pressure of 1 bar. Furthermore, robust antifouling properties were displayed by PA6/GO-PEG2, in which 95.69 % of the water flux rate was maintained and reached 778 L/m2h, and excellent oil rejection efficiency remained at 98.59 % even after 15 cycles of oil/water separation. These results highlight the potential of the PA6/GO-PEG2 nanofibrous membrane as a highly promising candidate for practical applications in oil/water separation, owing to its superior performance and enduring antifouling characteristics.

Improving energy harvesting through femtosecond laser surface modification of PVDF/ZnS composite nanofibrous nanogenerators for electronic applications

Surface modification in ceramic/polymer composites holds paramount importance for electronic devices applications. Laser is a versatile and flexible device for modifying the surface characteristics of various materials. Here, we propose a novel approach to enhance the energy harvesting efficiency of polyvinylidene fluoride (PVDF) and zinc sulfide (ZnS) composite nanofibrous membranes through femtosecond laser surface modification. The electrospinning technique is used to produce nanofibers with a high β-phase content in a single step. The PVDF membrane was further enriched with ZnS nanoparticles to enhance the β-phase content. The membranes were systematically investigated using scanning electron microscopy (SEM), transmission electron microscopy (TEM), Electron Energy Loss spectroscopy (EELS), and Fourier-transform infrared spectroscopy (FTIR) to characterize their morphological and chemical properties. Femtosecond laser was employed to induce controlled surface modifications, resulting in hierarchical microstructures and surface functionalization. The results showed patterned tracks on the fiber surface while preserving its inherent nature. To validate its utility as an energy harvesting device, the membrane's capability was assessed by measuring the open circuit voltage. The results revealing average output voltages for nanogenerators treated with laser fluences of 0.5 J/cm2, 0.7 J/cm2, and 0.9 J/cm2 are 15.6 V, 25 V, and 17 V, respectively. The maximum output voltage is observed for a laser fluence of 0.7 J/cm2, attributed to the deeper structure created, increasing the surface area of contact and deformation in the structure. This work offers promising avenues for enhancing energy harvesting efficiency and expanding the scope of electronic devices such as sensors and actuators.

In-situ electrospinning PVB/Camellia oil/ZnO-TiO2 nanofibrous membranes with synergistic antibacterial and degradation of ethylene applied in fruit preservation

This work utilizes a handheld electrospinning device to prepare a novel nanofibrous composite membrane in situ for packaging freshness. It can realize pick-and-pack and is easy to operate. The nanofibrous membrane is based on PVB as the matrix material, adding Camellia oil (CO) and ZnO-TiO2 composite nanoparticles (ZT) as the active material. The antimicrobial property of the CO and the photocatalytic activity of the nanoparticles give the material good antimicrobial and ethylene degradation functions. Meanwhile, this nanofibrous membrane has good mechanical properties, suitable moisture permeability and good optical properties. The nanofibrous membrane are suitable for both climacteric and non- climacteric fruits. Its use as a cling film extends the shelf life of strawberries by 4 days and significantly slows the ripening of small tomatoes. Therefore, this nanofibrous membrane has great potential for application in the field of fruit preservation.

Facile dual-functionalization of PEN nanofibrous membranes with solar evaporation and photocatalysis for efficient dye wastewater purification

Purification of dye wastewater by combining photocatalytic degradation with solar energy-driven interfacial water evaporation has emerged as a promising approach to address water pollution in recent years. In this work, a high-performance polymer, polyarylene ether nitrile (PEN), was electrostatically spun to construct a robust nanofibrous substrate, then dual-functionalized using polyaniline (PANI) and titanium dioxide (TiO2) via a facile polydopamine (PDA)-assisted vacuum self-assembly method. Moreover, the CA of the PEN membrane after PDA and PANI@TiO2 treatment changes from 20° to 0° within 0.4 s, showing superhydrophilic properties and providing rapid water supply for water evaporation. PANI and TiO2 were employed as the photo-thermal conversion component and photocatalytic component, respectively. The fabricated dual-functionalized PANI@TiO2/PEN composite nanofibrous membrane exhibited a high water evaporation rate of up to 3.23 kg m−2 h−1 under a simulated solar illumination of 1 KW m−2. Owing to the reduction in the photoelectron-hole recombination rate promoted by PANI, the composite nanofibrous membrane demonstrated a favorable dye removal rate of 92.18% in 6 h for methylene blue (MB). Furthermore, the robust PEN nanofibrous skeleton conferred the composite membrane with thermal resistance and corrosion resistance properties, ensuring long-term performance in harsh environments. The facile fabricated PANI@TiO2/PEN membrane achieved comprehensive performance, offering a promising strategy by combining solar-driven interfacial water evaporation and photocatalytic degradation for water purification.

Structure design and performance optimization of PVDF-CTFE nanofibrous composite nanofiltration membrane modified by C–Cl active site grafting

The substrate membrane plays a crucial role in determining the performance of composite nanofiltration membranes prepared by interfacial polymerization (IP). In this study, persistent hydrophilic modification of polyvinylidene fluoride-co-chlorotrifluoroethylene (PVDF-CTFE) was achieved by incorporating N-methylglucamine (N-MG) without altering the membrane's morphology or pore size. Moreover, thin-film nanofibrous composite (TFNC) nanofiltration membranes were prepared using the surfactant assembly regulated interfacial polymerization (SARIP) method with the modified PVDF-CTFE@N-MG nanofibrous membrane as the substrate. The effect of N-MG addition on the substrate membrane's hydrophilicity and the structure and performance of the polyamide (PA) separation layer was investigated. The results showed that the addition of N-MG significantly improved the hydrophilicity of the PVDF-CTFE nanofibrous membrane. The TFNC-5 membrane, prepared with the modified PVDF-CTFE@N-MG nanofibrous membrane as the substrate, exhibited permeability exceeding 13.5 L m−2 h−1·bar−1 for various dye solutions at 3 bar pressure, with rejection rates above 98 %. It also demonstrated excellent selective separation performance (separation factor for NaCl/Orange G reaching 97.38) and long-term operational stability. This work provides a method for the preparation of low-pressure, high-flux nanofiltration membranes, which is applicable to seawater desalination and dye wastewater treatment.

Promoting renal I/R injury repair by in-situ electric stimulation using biodegradable piezoelectric polylactide/vitamin B2 composite nanofibrous membrane

Ischemia/reperfusion (I/R) injury during renal transplantation remains a prevalent challenge. Recent studies proposed protective effects against renal I/R injury using electric fields during organ preservation stage. However, I/R process extends to the post reperfusion stage and traditional electrical stimulation methods face limitations, requiring power sources and electrodes. Hence, there is a need for implantable, biodegradable materials capable of continuously generating electrical stimulation to treat kidney I/R injury over an extended period. In this work, a polylactide/Vitamin B2 (PLLA/VB2) composite nanofibrous membrane was designed. The incorporation of VB2 into PLLA, coupled with electrospinning, significantly enhanced its piezoelectric performance and flexibility, thereby enabling optimal adherence and efficient in-situ electrical stimulation. Experimental results underscored that PLLA/VB2 nanofibrous membrane could mitigate tubular injury, facilitate cell regeneration, and alleviate interstitial fibrosis possibly by preserving mitochondrial structure and function. This innovative approach not only pioneers new strategies for addressing I/R related conditions but also offers potential treatments for a range of diseases linked to oxidative stress.

Antibacterial Potential and Biocompatibility of Chitosan/Polycaprolactone Nanofibrous Membranes Incorporated with Silver Nanoparticles.

This study addresses the need for enhanced antimicrobial properties of electrospun membranes, either through surface modifications or the incorporation of antimicrobial agents, which are crucial for improved clinical outcomes. In this context, chitosan-a biopolymer lauded for its biocompatibility and extracellular matrix-mimicking properties-emerges as an excellent candidate for tissue regeneration. However, fabricating chitosan nanofibers via electrospinning often challenges the preservation of their structural integrity. This research innovatively develops a chitosan/polycaprolactone (CH/PCL) composite nanofibrous membrane by employing a layer-by-layer electrospinning technique, enhanced with silver nanoparticles (AgNPs) synthesized through a wet chemical process. The antibacterial efficacy, adhesive properties, and cytotoxicity of electrospun chitosan membranes were evaluated, while also analyzing their hydrophilicity and nanofibrous structure using SEM. The resulting CH/PCL-AgNPs composite membranes retain a porous framework, achieve balanced hydrophilicity, display commendable biocompatibility, and exert broad-spectrum antibacterial activity against both Gram-negative and Gram-positive bacteria, with their efficacy correlating to the AgNP concentration. Furthermore, our data suggest that the antimicrobial efficiency of these membranes is influenced by the timed release of silver ions during the incubation period. Membranes incorporated starting with AgNPs at a concentration of 50 µg/mL effectively suppressed the growth of both microorganisms during the early stages up to 8 h of incubation. These insights underscore the potential of the developed electrospun composite membranes, with their superior antibacterial qualities, to serve as innovative solutions in the field of tissue engineering.

Dual-functional TFNC polyester membranes utilizing maltitol for dye/salt separation and desalination

To achieve a promising application prospect in nanofiltration (NF) membrane separation, a strategic design tailored to particular functions is crucial. Here, tailor-made thin film nanofibrous composite (TFNC) NF membranes for specific applications were fabricated via interfacial polymerization (IP) between maltitol and trimesoyl chloride (TMC) on PAN nanofibrous substrates. Owing to the moderate reactivity of maltitol, a range of sugar alcohol based polyester membranes with different morphologies and cross-linking degrees were obtained by varying the monomer concentration as well as the reaction time. In this case, the finely tuned loose Mal1-TMC0.2-2 membrane exhibited a prominent permeability (110.34 L m−2 h−1 bar−1) and an extraordinary selectivity for dye/salt mixed solution, with the rejection of Congo Red up to 99.11 % and NaCl retention of only 7.41 %, indicating its suitability for textile wastewater treatment. Further, the dense Mal2-TMC0.4-10 membrane showed an excellent Na2SO4 rejection of 97.40 % with a good permeability of 18.65 L m−2 h−1 bar−1, making it a candidate for seawater and brackish water desalination. In addition, both membranes demonstrated reliable chlorine and pressure resistance along with long-term stability. This study provided new insights and inspiration to the design and preparation of NF membranes for specialized applications.

Polyvinyl alcohol-encapsulated cerium oxide nanospheres composite nanofiber membrane for enhanced antioxidant and antibacterial applications☆

Cerium oxide (CeO2) has attracted much attention in recent years owing to its reversible switch ability in Ce3+/Ce4+ redox to produce improved antioxidation properties for biomedical applications. Here, we report to embed the CeO2 nanospheres into the organic polymer network using electrostatic spinning technology to prepare polyvinyl alcohol (PVA)-encapsulated CeO2 nanospheres composite nanofibrous membranes (PVA-CeO2) for the first time, which is beneficial to improving the dispersion and biocompatibility of CeO2 nanosphere without altering the original antioxidant properties of CeO2. Detailed characterization of the as-prepared composite nanofibrous membranes reveals that CeO2 was successfully introduced into the PVA fibers with strong interactions, thus enhancing the thermal stability and fracture toughness of the nanofibers. As a result, PVA-CeO2 exhibits superior UV shielding performance, antioxidant performance and bacteriostatic performance. Meaningfully, PVA-CeO2 has strong absorbance in both UVA and UVB bands when the CeO2 concentration in the nanofiber membrane reaches 1.5 wt%, and shows an excellent scavenging effect on the 2,2-diphenyl-1-picrylhydrazyl (DPPH) radicals with a scavenging rate of 86.52%. Moreover, the Kirby-Bauer (K-B) method of agar diffusion test further confirms that PVA-CeO2 has antimicrobial ability against three types of representative strains, including Gram-positive bacteria (Staphylococcus aureus), Gram-negative bacteria (Escherichia coli) and fungi (Candida albicans). Importantly, no obvious cytotoxicity is observed for PVA-CeO2 even though the amount of embedded CeO2 nanosphere reaches as high as 1.5 wt%. This study reveals new avenues for improving the future smart design of CeO2-based nanofiber membrane composite materials for biological antioxidants.

A bi-functional nanofibrous composite membrane for wound healing applications.

Various wound dressings have been developed so far for wound healing, but most of them are ineffective in properly reestablishing the skin's structure, which increases infection risks and dehydration. Electrospun membranes are particularly interesting for wound dressing applications because they mimic the extracellular matrix of healthy skin. In this study, a potential wound healing platform capable of inducing synergistic antibacterial and antioxidation activities was developed by incorporating bio-active rosmarinic acid-hydroxyapatite hybrid (HAP-RA) with different contents (0.5, 1, and 1.5 wt.%) into the electrospun polyamide 6 (PA6) nanofibers. Then, polyethylene glycol (PEG) was introduced to the nanofibrous composite to improve the biocompatibility and biodegradability of the dressing. The results indicated that the hydrophilicity, water uptake, biodegradability, and mechanical properties of the obtained PA6/PEG/HAP-RA nanofibrous composite enhanced at 1 wt.% of HAP-RA. The nanofibrous composite had excellent antibacterial activity. The antioxidation potential of the samples was assessed in vitro. The MTT assay performed on the L929 cell line confirmed the positive effects of the nanofibrous scaffold on cell viability and proliferation. According to the results, the PA6/PEG/HAP-RA nanofibrous composite showed the desirable physiochemical and biological properties besides antibacterial and antioxidative capabilities, making it a promising candidate for further studies in wound healing applications.

Research upon Cu-Doping Contents in TiO2 Nanoparticles Incorporated onto Cellulose Nanofibers for Dye Removal and Self-Cleaning Applications.

Cu-doping contents in the TiO2 lattice structure were studied to show the effects on the crystal structure, morphology, and photocatalytic activity of TiO2 nanoparticles and thus composite cellulosic nanofibrous membranes. Pristine and copper-doped TiO2 nanoparticles were synthesized using the sol-gel technique, a wet chemical method with the advantages of low synthesizing temperature, uniform nanosize distribution, and purity. The as-synthesized semiconductor nanoparticles were first tested with the dye removal process and then impregnated onto electrospun cellulose nanofibers (CL nanofibers) to acquire modified nanofibers with self-cleaning properties. The as-prepared composite CL nanofibers consisting of doped and undoped TiO2 nanoparticles were characterized by various techniques, such as field emission scanning electron microscopy, transmission electron microscopy, UV-vis, X-ray diffraction, Fourier transform infrared spectroscopy, and tensile tests. The copper-doped TiO2 molar ratio in the nanocomposite was found to possess a pronounced impact on the dye removal and self-cleaning effects under the visible light spectrum, whereas TiO2 is highly effective under specific UV-light irradiation. Optical measurements and dye decomposition showed that the Cu-doped TiO2 nanocomposite was optimized at a 1% molar ratio by the copper-doping concentration regarding dye removal and self-cleaning applications under the visible light range.

Superhydrophilic and underwater superoleophobic polylactide/cellulose diacetate composite nanofibrous membranes for effective oil-in-water emulsions separation

Electrospun polylactide (PLA) fibrous membranes, characterized by good biodegradability and high porosity, demonstrate significant potential for oily wastewater treatment. However, the inherent hydrophobicity of PLA poses a significant challenge in separating oil-in-water emulsions. Herein, a facile and effective strategy was proposed to fabricate a PLA based nanofibrous membrane for oil-in-water emulsions separation. By combining the electrospinning and nonsolvent-induced phase separation technologies, hydrophilic cellulose diacetate (CDA) networks were in-situ constructed throughout the entire body of PLA fibrous membrane, resulting in a unique hierarchical porous structure. As a result, the obtained PLA/CDA composite nanofibrous membrane exhibited intriguing superhydrophilicity and underwater superoleophobicity, as well as gratifying separation performances for various oil-in-water emulsions solely under the driving force of gravity. Furthermore, the PLA/CDA composite nanofibrous membrane could be easily reused and will not bring out significant environmental concerns after extended use and disposal. We anticipate that this work could pave a way for the development of environmentally friendly membranes for oily wastewater treatment.

Hairy quaternary ammonium-functionalized metal organic framework integrated in polyacrylonitrile nanofiber membrane for efficient removal of arsenate

In this work, the metal–organic framework (MOF) particles (i.e., UiO-66-NH2) was covalently modified with poly(4-vinylpyridine) (P4VP) through surface-initiated atom transfer radical polymerization (SI-ATRP) method. The hair MOF product, referred to as UiO-66-g-P4VP, was then subjected to quaternization with 1-bromoethane, resulting in UiO-66-g-qP4VP (quaternized P4VP is denoted as qP4VP). Finally, these UiO-66-g-qP4VP particles were incorporated into a polymer matrix made of polyacrylonitrile (PAN) to develop a nanofibrous composite membrane using the electrospinning technique. After modification of quaternized P4VP, the surface of the MOFs carry strong positive charges. Therefore, the electrospun UiO-66-g-qP4VP/PAN nanofiber membrane can serve as an adsorbent in efficient removal of negatively charged arsenate through strong electrostatic interactions. The adsorptive efficacy of the nanofiber membrane exhibited considerable stability within the pH spectrum extending from 4 to 10, indicating that the membrane could potentially maintain its functionality across a broad range of pH conditions. Our developed approach opens up an avenue for manufacturing of polyelectrolyte-functionalized MOF nanofiber membranes, which hold great promise for application in water remediation.

A BaTiO3@polyacrylonitrile/poly(vinylidene fluoride) nanofibrous composite membrane with high piezoelectricity based on the central combination design method and cross-electrospinning technology

The rapid development of piezoelectric sensors has been studied extensively, owing to their good flexibility, wearability, high sensitivity and low cost. However, some inorganic materials with good piezoelectricity cannot make sensors flexible, and the organic materials with good flexibility have a weak output electrical signal and low strength. In order to explore and optimize the preparation technology of piezoelectric sensors, a BaTiO3@polyacrylonitrile (PAN)/poly(vinylidene fluoride) (PVDF) nanofibrous composite membrane (NCM) was prepared by cross-electrospinning technology and the central combination design (CCD) method. The morphology, structure, hydrophobicity, mechanical properties and piezoelectricity of the BaTiO3@PAN/PVDF NCMs were investigated. The BaTiO3@PAN/PVDF NCMs had the better hydrophobicity and mechanical properties compared with the pure PAN/PVDF NCM. The 5BaTiO3@PAN/PVDF NCM designed by CCD had a more uniform fiber diameter, and a more stable output voltage with a 46% improvement. With the help of cross-electrospinning technology and the CCD method, the NCM will be outstanding for the development of fabricating flexible wearable piezoelectric sensors.

Lactosporin loaded electrospun nanofibrous membrane: Novel antibacterial and wound dressing patch

IntroductionAny disruption in the cohesion of skin tissue is called a skin ulcer. If the skin lesion is a superficial lesion, it heals easily. But some wounds, such as diabetic wounds, bedsores, and burns, are difficult to heal and are often associated with infection. Therefore, one of the new methods used to treat such wounds is skin patch. MethodIn this study, partly purified lactosporin (LP), as novel postbiotic, was extracted from Bacillus coagulans, and its antibacterial properties against six bacterial species, namely Escherichia coli, Micrococcus Luteus, Pseudomonas aeruginosa, Staphylococcus aureus, Staphylococcus epidermis, and Klebsiella pneumonia were investigated. An electrospun nanofibrous membrane (NFM) containing LP was electrospun based on the three polymers including hyaluronic acid (HA), chitosan, and polyvinyl alcohol (PVA) and its potential for biomedical applications was analized. The morphological characteristics, hydrophilic properties, cytotoxicity, and wound healing potential of LP-loaded NFMs were investigated. ResultsIt was revealed that extracted LP includes supperior antibacterial properties, which is beneficial for developing wound dressing patches. The results showed fabricated composite NFMs are bead-free and uniform. The average diameter of uncross-linked and cross-linked nanofibers are 281 ± 10 nm and 359 ± 51 nm, respectively. These NFMs are hydrophilic in both cross-linked and uncross-linked forms and the contact angles of them were 39 and 13°, respectively. These NFMs were also tested for cytotoxicity by the MTT assay and were found to be non-toxic. ConclusionThese results indicate that HA/CS/PVA/LP NFM could act as an efficient antibacterial and multifunctional wound dressing patch.