Nanofibrous Membranes Research Articles

Preliminary investigation of nanofibrous membranes for sound absorption

Nanofibrous membranes show interesting mechanical properties, low thickness and lightness, besides the possibility of using a great variety of polymers. The electrospinning technique makes possible the production of polymeric random nanofibres to form nonwoven membranes, which are currently used in several application fields, such as filtration, biomedicine, biomechanics, electronics, and composite materials. Their application in the automotive and aerospace engineering field could bring significant benefits to the acoustic comfort design. However, their acoustics properties still need to be further assessed. This study investigates the acoustic absorption of electrospinning-made nanofibrous membranes in Nylon 66 with different fibre diameters and mat thicknesses. Morphological and thermal characterisation of the electrospun membranes have been assessed via Scanning Electron Microscope (SEM) and Differential Scanning Calorimetry (DSC), respectively. The acoustic absorption characteristics of various samples changing fibre diameter, membrane thickness and mounting conditions were tested in the impedance tube. The results showed more relevant acoustic absorption properties in the nanofibrous membrane coupled with a polyester fibre. Further studies will clarify if filament direction and constituent material can be improved for a more durable and resistant membrane application.

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.

Modification of transvaginal polypropylene mesh with co-axis electrospun nanofibrous membrane to alleviate complications following surgical implantation

BackgroundSurgeries for treating pelvic organ prolapse involving the utilization of synthetic mesh have been associated with complications such as mesh erosion, postoperative pain, and dyspareunia. This work aimed to reduce the surgical implantation-associated complications by nanofibrous membranes on the surface of the polypropylene mesh. The nanofiber of the nanofibrous membrane, which was fabricated by co-axial electrospinning, was composed of polyurethane as fiber core and gelatin as the fiber out layer. The biocompatibility of the modified mesh was evaluated in vitro by cell proliferation assay, immunofluorescence stain, hematoxylin-eosin (HE) staining, and mRNA sequencing. Polypropylene mesh and modified mesh were implanted in a rat pelvic organ prolapse model. Mesh-associated complications were documented. HE and Picro-Sirius red staining, immunohistochemistry, and western blotting were conducted to assess the interactions between the modified mesh and vaginal tissues.ResultsThe modified mesh significantly enhanced the proliferation of fibroblasts and exerted a positive regulatory effect on the extracellular matrix anabolism in vitro. When evaluated in vivo, no instances of mesh exposure were observed in the modified mesh group. The modified mesh maintained a relatively stable histological position without penetrating the muscle layer or breaching the epidermis. The collagen content in the vaginal wall of rats with modified mesh was significantly higher, and the collagen I/III ratio was lower, indicating better tissue elasticity. The expression of metalloproteinase was decreased while the expression levels of tissue inhibitor of metalloproteinase were increased in the modified mesh group, suggesting an inhibition of collagen catabolism. The expression of TGF-β1 and the phosphorylation levels of Smad3, p38 and ERK1/2 were significantly increased in the modified mesh group. NM significantly improved the biocompatibility of PP mesh, as evidenced by a reduction in macrophage count, decreased expression levels of TNF-α, and an increase in microvascular density.ConclusionsThe nanofibrous membrane-coated PP mesh effectively reduced the surgical implantation complications by inhibiting the catabolism of collagen in tissues and improving the biocampibility of PP mesh. The incorporation of co-axial fibers composed of polyurethane and gelatin with polypropylene mesh holds promise for the development of enhanced surgical materials for pelvic organ prolapse in clinical applications.

Poly (lactic acid) electrospun nanofiber membranes: Advanced characterization for biomedical applications with drug loading performance studies

Traditional dressings have shortcomings such as poor moisture absorption and easy to adhere, making the development of new dressings crucial. In this work, a PLA/PVP crosslinked drug-loaded nanofiber membrane was prepared through electrospinning and ultraviolet crosslinking, with poly (lactic acid) (PLA), polyvinylpyrrolidone (PVP), and salicylic acid (SA) as starting materials. The results demonstrated that the inclusion of PVP notably boosted the viscosity and conductivity of the blend spinning solution. The roughness of the fabricated fiber was elevated, and the diameter of the fibers was more uniform. Additionally, the incorporation of PVP not only enhanced the porosity of the fiber membrane but also effectively decreased its contact angle. Notably, when the PVP content reached 40 %, the contact angle underwent a substantial reduction, decreasing significantly from 125.4° to 82.2°. The SA drug-loaded fiber membrane exhibited a notable bacteriostatic effect against Escherichia coli and Staphylococcus aureus, with its release behavior adhering to Fick's diffusion law. In the cell viability experiment, the cell proliferation rate increased from 94 % to 129 % after 3 days. This shows that the prepared membrane has good antibacterial effect and cell compatibility, which provides a theoretical basis for the construction of a new medical dressing.

Fluorine-free biomimetic membranes with leaf vein-like and lotus leaf dual structure for high-performance waterproof and breathable textiles

Intelligent microporous membranes with excellent water resistance and moisture permeability have a huge market demand owing to their wide applications in personal protection, outdoor equipment and wearable electronics. However, the construction of such high-performance waterproof and moisture-permeable membranes (WBMs) based on a simple preparation process without post-coating treatment presents significant challenges. Herein, we present a simple strategy for constructing a fluorine-free polyethylene terephthalate (PET)-based WBM with a novel composite structure by combining a leaf vein-like nanofibrous substrate membrane and lotus leaf-inspired biomimetic nanofibrous skin using multi-needle electrospinning and heat treatment techniques. Surface hydrophobicity, along with the stable crosslinked structure of PET-based membranes, was achieved by in-suit doping of fluorine-free two-component reactive silicone rubber (PDMS). In addition, the small pore size and high porosity of the composite membranes were regulated by co-assembling PET/PDMS fibers and microspheres with different morphologies and structures. The resulting composite membranes based on substrate membrane-1:3 (BNFM-1:3) achieved excellent waterproof performance of 90.3 kPa, good moisture permeability of 5116 g m−2 d−1, and air permeability of 1.82 mm s−1. The WBMs based on novel composite structures are expected to be applied in various fields because of their ideal comprehensive performance.

Multifunctional Wearable Conductive Nanofiber Membrane with Antibacterial and Breathable Ability for Superior Sensing, Electromagnetic Interference Shielding, and Thermal Management

Multifunctional Wearable Conductive Nanofiber Membrane with Antibacterial and Breathable Ability for Superior Sensing, Electromagnetic Interference Shielding, and Thermal Management

Flexible and ferroelectric electrospun PVDF- non-stoichiometric PZT nanogenerators (PENGs) membranes for low-frequency acoustic energy harvesting

Acoustic energy harvesting (AEH) at low-frequency has been exposed to serious problems such as low energy of input sound and lack of efficient materials to absorb the sound and convert it to electrical power. This study focused on the enhancement of the AEH performance of polyvinylidene fluoride (PVDF) membrane via the incorporation of non-stoichiometric PZT (nsPZT) nanoneedles as piezoelectric nanogenerators (PENG). The nanofibrous membranes with different amounts of PENG (x = 0, 2.5, 5, and 10 wt %) were synthesized by the electrospinning method. The nsPZT was provided via Nd3+ and Nb5+ co-doping as a novel approach. The microstructures revealed that the PENG was embedded well inside the fibers (x = 2.5), while the agglomerates were formed at higher amounts (x = 10). Also, the fiber diameters and porosity of membranes were changed. It was found that the maximum crystallization of the β-phase of PVDF has occurred at x = 2.5 (71 %). The dielectric of the PVDF membrane decreased with increasing the x factor due to the formation of further pores. In contrast, the ferromagnetic properties, piezoelectric sensitivity, and electrical conductivity were improved by adding the PENG. The maximum coercivity of 750 Oe, piezoelectric sensitivity of 1.959 V N−1, and minimum sheet resistance of 1.2 kΩ.sq−1 were achieved by x = 2.5. The noise reduction coefficient (NRC) of the PVDF membrane was enhanced drastically (53–163 %) by adding the PENG. The AEH performance was also enhanced by adding the PENG. The highest power density was achieved 0.0822 W g−1 (56.23 W m−2) by the PVDF-PENG membrane (x = 2.5) under 90 dB sound pressure at 2000 Hz frequency. These findings suggest the high potential of nanofibrous PVDF-PENG membrane for use in low-frequency AEH systems.

Removal of lysozyme as protein waste using weak ion exchange nanofiber membrane in a batch system: Linear and nonlinear model analysis

This study investigates the removal of lysozyme, a common waste protein, using weak ion-exchange nanofiber membranes (P-COOH) to address challenges in protein waste management and wastewater treatment. Protein waste, prevalent in industrial and biological processes, contributes to environmental pollution and increases treatment complexity if not effectively managed. Conventional methods often face limitations in selectivity and efficiency, highlighting the need for innovative solutions. The P-COOH nanofiber membrane, with its high surface area and tailored functional groups, was engineered to optimize protein removal. The removal process was analyzed in a batch system at an optimal pH of 7. Various kinetic models, such as pseudo-first-order, pseudo-second-order, Avrami, and intra-particle diffusion, were applied to elucidate rate-controlling steps. In contrast, isotherm models, including Langmuir, Freundlich, and Temkin, characterized the equilibrium of the removal process. Complete elution of removed lysozyme was achieved using a 0.3 M NaCl solution, yielding an equilibrium binding capacity of 315.24 mg/g on the nanofiber membranes. These findings indicate that the Avrami nonlinear model best describes lysozyme removal's complex, multi-step kinetics. In contrast, the Langmuir linear model accurately fits the equilibrium data, suggesting monolayer removal on a homogeneous surface. The successful reusability of the membranes underscores their potential for sustainable lysozyme removal from wastewater, offering a viable solution for improved waste management in industrial 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.

Tannin-encapsulated electrospun nanofibrous membrane of cellulose nanowhiskers-reinforced polysulfone for colorimetric detection of iron(III)

A nanocomposite of tannic acid and cellulose nanowhiskers (CNW)-reinforced polysulfone (PSF) was used to develop a metallochromic nanofibrous membrane sensor for iron(III) in aqueous media. Tannic acid was used as an active detecting probe, whereas the CNW@PSF composite was employed as a hosting material. Cellulose nanowhiskers (7–12 nm) were obtained from microcrystalline cellulose (MCC). According to the coloration parameters, a bathochromic shift from colorless (415 nm) to purple (561 nm) occurs when ferric cations bind to the phenolic hydroxyls of the tannic acid probe. The concentration of ferric was found to be directly correlated to the extent of the color change, demonstrating a detection limit of 0.1–250 ppm. This could be attributed to the creation of a coordinative complex between ferric ions and phenolic tannic acid. The generated nanofibers were inspected by energy-dispersive X-ray (EDX) and scanning electron microscopy (SEM). The electrospun nanofibrous membrane showed an average diameter between 75 and 150 nm. The tannic acid-containing nanofibers are remarkably reusable and simple. The tannic acid-encapsulated polysulfone nanofibrous membrane was used to detect various metal ions, demonstrating a high selectivity for Fe3+. The ideal pH range for the identification of Fe3+ was determined to be in the range of 4.25–6.75.

Antibacterial, antioxidant and barrier properties of clay-doped electrospun fibers

Nowadays, packaging technologies have been extensively developed, including active and intelligent packages able to promote quality, safety, and the product shelf life. At this purpose, the aim of the study was focused on the design and development of polyvinyl alcohol-based nanofibers doped with two natural clays, montmorillonite or clinoptilolite, and loaded with chlorogenic acid, as nanofibrous membranes to control microbial contamination and oxidative state upon direct contact. The results showed that the 1 % w/w clay doping was the optimal concentration to obtain continuous and uniform nanofibers. In addition, chlorogenic acid loading (5 % w/w) into the nanofibers did not change the systems morphology, resulting in a chlorogenic acid sustained release, achieving 100 % within 24 h for all the systems with enhanced antioxidant and antimicrobial activities. Depending on their structure, the presence of the clays mineral was able to affect the aqueous vapor permeability. These results suggested the promising applications of the clay doped polyvinyl alcohol-based nanofibrous membranes as smart advanced material able to control microbial contamination and oxidative degradation to be used in biomedical field or as active packaging.

Efficient photocatalytic degradation of tetracycline and its derivatives by green recyclable PAN/Bi2WO6/Cu2O nanofiber membrane

The use of tetracycline antibiotics in industry, healthcare, animal husbandry, agriculture, and aquaculture has resulted in excessive concentrations in a variety of aquatic environments. In this work, PAN/Bi2WO6/Cu2O nanofibrous membranes (PBC ENMs) with photocatalytic degradation performance were successfully prepared using electrostatic spinning technique, and the morphology of catalysts and PBC ENMs were characterised by SEM, BET and UV–Vis. The results demonstrated that the prepared nanofibrous membranes could achieve 97.05 % photocatalytic degradation of TC under visible light, and the degradation efficiencies of its derivatives, chlortetracycline (CTC) and oxytetracycline (OTC), reached 90.87 % and 85.12 %, respectively. Free radical trapping experiments and mechanistic analyses showed that·O2– is the main active factor in the degradation process. The highest degradation rate of 97.05 % was achieved at initial pH = 7.2.PBC ENMs adsorbed above 87.5 % after six cycles of the experiment. The highest degradation rate of 97.05 % was achieved at initial pH = 7.2 PBC ENMs adsorbed above 87.5 % after six cycles of the experiment. Based on the above advantages, the preparation process of PBC ENMs is simple, low-cost and has good catalytic effect, which provides a simple and efficient treatment means for the treatment of TC wastewater and has a broad application prospect.

Development of red fluorescent probe for visual detection of N2H4 via nanofiber membrane and its application in environmental analysis and biological imaging

Hydrazine (N2H4) is widely used in most industrial production. It is a harmful environmental pollutant and has strong toxicity to living organisms. Hence, it is imperative to employ approach for the real-time monitoring and tracking of N2H4. In this study, we developed the fluorescent probe DYY, incorporating an acetyl group as the recognition moiety, to achieve efficient detection of N2H4. The findings revealed that DYY exhibits excellent sensitivity (with a detection limit of 81 nM) and a wide pH range (2−8) in the detection of N2H4. Notably, upon the addition of N2H4, the color of the DYY solution transitioned from purple to blue, accompanied the fluorescence intensity increased by 11-fold increase in 643 nm. In addition, DYY demonstrated its capability in detecting N2H4 contamination within environmental water samples. Significantly, polymer nanofibers embedded with DYY were fabricated through the process of electrospinning, allowing for the visual identification of N2H4. Furthermore, it showed excellent performance in detecting N2H4 in HepG2 cells and zebrafish, demonstrating its potential for labeling N2H4 in living systems. Therefore, we are confident that this probe holds significant potential for environmental analysis and the detection of health indicators in living organisms.

Carbon-encapsulated silicon ordered nanofiber membranes as high-performance anode material for lithium-ion batteries

Silicon have attracted much attention as a promising anode material for lithium-ion batteries due to the extremely high theoretical capacity. However, its practical application is limited by the huge volume expansion during the cycling process. To address this issue, carbon-encapsulated silicon ordered nanofiber membranes were designed through a modified electrospinning technology with a strong magnetic field. Compared with the conventional nanofiber membranes, the optimized M1200 Gs anode exhibited a high discharge capacity of 1603.1 mAh·g−1 at 0.1 A·g−1, a superior rate performance, and a robust cycling stability with a reversible capacity of 658.1 mAh·g−1 at 1 A·g−1 after 100 cycles. The improved electrochemical performance was confirmed to be highly correlated with the parallel structure of nanofibers, which help to facilitate the diffusion and transport of electrons and ions, realize the stress distribution and buffer the volume changes. This work provides unique insights into designing silicon-based anodes with novel structures for lithium-ion batteries.

Iron metal-organic framework nanofiber membrane for the integration of electro-Fenton and effective continuous treatment of pharmaceuticals in water

In this study, an iron metal-organic framework (Fe-MOF) was synthesized and immobilized by electrospinning technique with the objective of obtaining a membrane composed of nanofibers of this material (Fe-MOF nanofiber membrane). The characterization performed by XRD, TEM, SEM, EDS mapping and FTIR confirmed the correct synthesis of Fe-MOF as well as its correct retention in the elaborated membranes. The usefulness and effectiveness of the Fe-MOF nanofiber membrane as a catalyst for the electro-Fenton process was evaluated by performing sulfamethoxazole degradation tests. Different parameters such as the effect of intensity (25 and 100 mA), the effect of the drug initial concentration (10–50 mg/L) and the reusability of membranes were studied. Then, the degradation of a drug mixture formed by sulfamethoxazole and antipyrine was evaluated, reaching a degradation of 92.10 % and 87.43 % respectively for each drug in 4 h at 25 mA. In addition, the identification of reactive oxygen species was ascertained by scavenger assays. The study of degradation products was also carried out and their toxicity was predicted by ECOSAR program, concluding that the environmental toxicity would disappear with mineralization. Finally, given the good results obtained in batch tests, the behavior of the process was studied in a system that works continuously, achieving a stable degradation of 83.10 % in the case of treatment with a mixture of drugs. This confirmed the stability of the Fe-MOF nanofiber membrane, as well as, its catalytic activity, making it suitable for long-term treatments.

Preparation of a nanofiber membrane loaded with Melastoma dodecandrum Lour. Extract for rapid hemostasis

Melastoma dodecandrum Lour. is a plant with a rapid hemostatic effect that is mainly distributed in Guizhou, Guangxi, Guangdong, and other provinces in China. In this study, we prepared a new rapid hemostatic wound dressing using Melastoma dodecandrum Lour. extract (MDLE). Nanofiber membranes (PVA/CS/MDLE) consisting of polyvinyl alcohol (PVA), chitosan (CS), and different doses of MDLE were prepared using an electrospinning method.Then, each group of nanofiber membranes was characterized using SEM, FTIR, and XRD. The diameters of PVA/CS, PVA/CS/2.8 %-MDLE, PVA/CS/5.5 %-MDLE, and PVA/CS/8.2 %-MDLE were 207.2 ± 36.65 nm, 313.3 ± 68.14 nm, 350.0 ± 80.55 nm, and 371.1 ± 82.84 nm, respectively. PVA/CS/2.8 %-MDLE exhibited the greatest mechanical strength, while PVA/CS/5.5 %-MDLE exhibited the greatest elongation at break. PVA/CS/5.5 %-MDLE and PVA/CS/8.2 %-MDLE exhibited significant bacteriostatic effects and inhibited Staphylococcus aureus more effectively than Escherichia coli. The PVA/CS/8.2 %-MDLE group had a significant hemostatic effect (P < 0.001), and all groups exhibited hydrophilicity, swelling ratios, and low toxicity. As the drug concentration increased, the time required for hemostasis decreased. Overall, these findings demonstrated that the PVA/CS/MDLE has great potential as a wound dressing. To our knowledge, this is the first time that a functional nanofiber with rapid hemostasis has been successfully prepared using MDLE.

Bio-inspired fabrication of Ag-ZnO nanoparticle decorated Nylon 11 nanofibers: Multifunctional membrane for environmental remediation

Traditional wastewater treatment methods using nanoparticles encounter challenges with catalyst recovery. In this study, we fabricated a Nylon 11 nanofibrous membrane (NFM) via electrospinning and functionalized it with polydopamine to immobilize Ag-ZnO nanoparticles for photocatalytic degradation of organic pollutants. The Nylon 11 NFM was treated with a dopamine tris buffer solution for polydopamine (PDA) coating, which facilitated mussel-inspired attachment of the ZnO nanoparticles. These nanoparticles served as a nucleation site for the biomimetic nucleation of Ag-ZnONPs during the hydrothermal process. The synthesized composite membrane was characterized by various microscopic and spectroscopic techniques. The water contact angle decreased from 135° (Nylon 11 NFM) to 41° (PDA/Nylon 11 NFM) and the filtration efficiency improved 10 folds (from 15.92 Lm-2 hr-1 to 170.60 Lm-2hr-1) at ambient conditions. The Ag-ZnO/PDA/Nylon 11 NFM showed strong antimicrobial activity against different bacterial strains and excellent photocatalytic degradation for methyl orange with a rate constant of 0.0431 min-1, significantly surpassing other configurations. The membrane exhibited excellent stability, reusability and consistent photocatalytic efficiency over multiple cycles. It is easily recoverable from the reaction mixture, and suitable for repeated use, making it a promising candidate for environmental remediation due to its antibacterial properties, photocatalytic activity, enhanced filtration efficiency, and reusability.

Nanocarrier-Assisted Delivery of Berberine Promotes Diabetic Alveolar Bone Regeneration by Scavenging ROS and Improving Mitochondrial Dysfunction.

Oxidative stress and mitochondrial dysfunction are potential contributors to the compromised tissue regeneration capacity of alveolar bone in diabetic patients. Berberine, an active plant alkaloid, exhibits multiple pharmacological effects including antioxidation, blood glucose- and blood lipid-lowering properties. However, it remains uncertain whether berberine can improve impaired osteogenesis in type 2 diabetes mellitus (T2DM), and its poor solubility and oral bioavailability also constrain its applications in bone regeneration. Thus, our study aimed to probe the effects of berberine on bone marrow stem cells (BMSCs) in a diabetic microenvironment, with a greater emphasis on developing a suitable nano-delivery system for berberine and assessing its capability to repair diabetic alveolar bone defects. Firstly, BMSCs were exposed to berberine within a high glucose and palmitate (HG+PA) environment. Reactive oxygen species levels, mitochondrial membrane potential, ATP generation, cell apoptosis, and osteogenic potential were subsequently assessed. Next, we explored the regulatory mechanism of autophagy flux in the positive effects of berberine. Furthermore, a nanocarrier based on emulsion electrospinning for sustained local delivery of berberine (Ber@SF/PCL) was established. We assessed its capacity to enhance bone healing in the alveolar bone defect of T2DM rats through micro-computed tomography and histology analysis. Berberine treatment could inhibit reactive oxygen species overproduction, mitochondrial dysfunction, apoptosis, and improve osteogenesis differentiation by restoring autophagy flux under HG+PA conditions. Notably, Ber@SF/PCL electrospun nanofibrous membrane with excellent physicochemical properties and good biological safety had the potential to promote alveolar bone remodeling in T2DM rats. Our study shed new lights into the protective role of berberine on BMSCs under T2DM microenvironment. Furthermore, berberine-loaded composite electrospun membrane may serve as a promising approach for regenerating alveolar bone in diabetic patients.

Polycaprolactone/gelatin-QAS/bioglass nanofibres accelerate diabetic chronic wound healing by improving dysfunction of fibroblasts

Worldwide, more than 25 % of patients with diabetes develop chronic diabetic wounds in their lifetime. Infection and dysfunctional fibroblasts represent two significant etiological factors contributing to impaired wound healing in patients with diabetes. It is therefore evident that the development of wound dressings with both anti-infective and DM fibroblast modulating functions has the potential for clinical applications. In this study, a PCL/gelatine-quaternary ammonium salts (QAS)/bioglass (BG) electrospun nanofibrous membrane was developed with physico-chemical and biological properties that not only meet the clinical requirements for wound dressings but also exhibit remarkable moisturising (water adsorption rate of 382.39 ± 4.36 %) and tear-resistance properties (a tear strength of ~5.5 MPa). The incorporation of QAS and BG has enhanced the biocompatibility and bioactivity of the nanofibres, while also imparting remarkable antimicrobial properties. The antibacterial efficacy of PGQ-BG against E. coli and S. aureus was found to be 92.8 ± 0.78 % and 99.3 ± 0.55 %, respectively. Moreover, it was demonstrated that PGQ-BG nanofibers exerted a promoting effect on the extracellular matrix (ECM) in dysfunctional fibroblasts and upregulated the expression level of α-smooth muscle actin (α-SMA), a marker of their differentiation to myofibroblasts in vitro and in vivo. Furthermore, the COL-III/COL-I ratio was significantly increased, indicating that PGQ-BG may also accelerate wound healing. The nanofibrous dressing reduced scar formation by increasing the COL-III/COL-I ratio. This is the first report of BG improving fibroblast dysfunction via COL-III and COL-I promotion in fibroblasts, both in vitro and in vivo. Therefore, this novel bioactive nanofibrous dressing represents an effective and safe therapeutic strategy for improving chronic wound healing in patients with diabetes.

3D nanofiber sponge based on natural insect quaternized chitosan/pullulan/citric acid for accelerating wound healing

Extensive traumatic injuries and difficult-to-heal wounds, induced by many circumstances, impose a significant social and economic burden on an annual basis. Thus, innovative wound dressings that encourage wound healing are greatly needed. In this work, we prepared a novel insect chitosan (MCS) using waste pupal shells from housefly (Musca domestica L.) culture. After conducting comparative investigations with commercially available chitosan, it was shown that MCS exhibited comparable qualities and may be used as a substitute source of commercial chitosan. A quaternized chitosan/pullulan/citric acid three-dimensional nanofiber sponge (3D-NS) of natural origin was prepared by electrostatic spinning and gas foaming techniques after MCS was quaternized. In vitro, tests showed that the 3D-NS had a higher liquid absorption capacity than the two-dimensional nanofibrous membrane (2D-NM). Additionally, the 3D-NS showed improved hemostatic, pro-cell proliferation, antibacterial, and anti-inflammatory qualities. In vitro, tests demonstrated that 3D-NS could inhibit the release of inflammatory factors, promote angiogenesis, accelerate collagen deposition, and promote wound contraction. These effects considerably facilitated the healing process of wounds in rats with full-thickness skin damage. In conclusion, the great bioactivity and physicochemical properties of 3D-NS render it an optimal candidate for developing novel wound dressings.