Search Results (428)

Electrospun nanofiber membranes (ESNFMs) are exceptional biomaterials for tissue engineering, closely mimicking the native extracellular matrix. However, their inherent fragility poses significant handling, processing, and integration challenges, limiting their widespread application in advanced 3D tissue models and biofabricated devices. This study introduces a novel and on-mat framing technique utilizing extrusion-based printing of a UV-curable biocompatible resin (Biotough D90 MF) to create rigid, integrated support structures directly on chitosan–polyethylene oxide (PEO) ESNFMs. We demonstrate fabrication of these circular frames via precise 3D printing and a simpler manual stamping method, achieving robust mechanical stabilization that enables routine laboratory manipulation without membrane damage. The resulting framed ESNFMs maintain structural integrity during subsequent processing and exhibit excellent biocompatibility in standardized extract assays (116.5 ± 12.2% normalized cellular response with optimized processing) and acceptable performance in direct contact evaluations (up to 78.2 ± 32.4% viability in the optimal configuration). Temporal assessment revealed characteristic cellular adaptation dynamics on nanofiber substrates, emphasizing the importance of extended evaluation periods for accurate biocompatibility determination of three-dimensional scaffolds. This innovative biofabrication approach overcomes critical limitations of previous handling methods, transforming delicate ESNFMs into robust, easy-to-use components for reliable integration into complex cell culture applications, barrier tissue models, and engineered systems. Full article

Wound dressings prevent complications such as infections and potentially severe outcomes, including death, if wounds are left untreated. Wound dressings have evolved from rudimentary coverings made from natural materials to sophisticated, functionalized dressings designed to enhance wound healing and support tissue repair more effectively. These materials are often referred to as scaffolds in the literature, with wound dressing scaffolds intended to interact with native skin tissue and support tissue regeneration, whereas conventional wound dressings are designed primarily to protect the wound without directly interacting with the underlying tissue. However, there is a functional overlap between these categories, and the boundary is often blurred due to the increasing multifunctionality of modern wound dressings. This review will focus on developing wound dressings (scaffolds or not) based on fibers, their properties, and applications. Advances in nanomedicine have highlighted significant improvements in wound care by applying electrospun nanofibers that mimic the natural extracellular matrix. Therefore, this review explores recent advances in wound healing physiology, highlights nanofiber-based wound dressing materials developed through electrospinning, and distinguishes conventional dressings from multifunctional wound dressing scaffolds. Full article

Background/Objectives: A nanostructured membrane of polycaprolactone (a synthetic polymer) was synthesized using an electrospinning technique aiming to enhance its hydrophilicity and rate of degradation by surface modification via aminolysis. Since polycaprolactone nanofibrous films are naturally hydrophobic and with slow degradation, which restricts their use in biological systems, amino groups were added to the fiber surface using the aminolysis technique, greatly increasing the wettability of the membranes. Methods: Polycaprolactone nanofibrous membranes were synthesized via the electrospinning technique and surface modification by aminolysis. Trypsin, pepsin, and pancreatin were conjugated onto the aminolyzed PNF surface to further strengthen biocompatibility by enhancing the hydrophilicity, porosity, and biodegradation rate. SEM, FTIR, EDX, and liquid displacement method were performed to investigate proteolytic efficiency and morphological and physical characteristics such as hydrophilicity, porosity, and degradation rates. Results: Enzyme activity tests, which showed a zone of clearance, validated the successful enzyme conjugation and stability over a wide range of pH and temperatures. Scanning electron microscopy (SEM) confirms the smooth morphology of nanofibers with diameters ranging from 150 to 950 nm. Fourier transform infrared spectroscopy (FTIR) revealed the presence of O–H, C–O, C=O, C–N, C–H, and O–H functional groups. Energy-dispersive X-ray (EDX) elemental analysis indicates the presence of carbon, oxygen, and nitrogen atoms owing to the presence of peptide and amide bonds. The liquid displacement technique and contact angle proved that Pepsin-PNFs possess notably increased porosity (88.50% ± 0.31%) and hydrophilicity (57.6° ± 2.3 (L), 57.9° ± 2.5 (R)), respectively. Pancreatin-PNFs demonstrated enhanced enzyme activity and degradation rate on day 28 (34.61%). Conclusions: These enzyme-conjugated PNFs thus show improvements in physicochemical properties, making them ideal candidates for various biomedical applications. Future studies must aim for optimization of enzyme conjugation and in vitro and in vivo performance to investigate the versatility of these scaffolds. Full article

Extracellular vesicles (EVs) have emerged as promising acellular tools for modulating immune responses for tissue engineering applications. This study explores the potential of human fibroblast-derived EVs delivered within a three-dimensional (3D) injectable scaffold composed of polycaprolactone (PCL) nanofibers and collagen (PNCOL) to reprogram macrophage behavior and support scaffold integrity under inflammatory conditions. EVs were successfully isolated from human fibroblasts using ultracentrifugation and characterized for purity, size distribution and surface markers (CD63 and CD9). Macrophage-laden PNCOL scaffolds were prepared under three conditions: macrophage-only (MP), fibroblast co-encapsulated (F-MP), and EV-encapsulated (EV-MP) groups. Structural integrity was assessed via scanning electron microscopy and Masson’s trichrome staining, while immunomodulatory effects were evaluated through metabolic assays, gene expression profiling, and immunohistochemistry for macrophage polarization markers (CD80, CD206). When co-encapsulated with pro-inflammatory (M1) macrophages in PNCOL scaffolds, fibroblast-derived EVs preserved scaffold structure and significantly enhanced macrophage metabolic activity compared to the control (MP) and other experimental group (F-MP). The gene expression and immunohistochemistry data demonstrated substantial upregulation of anti-inflammatory markers (TGF-β, CD163, and CCL18) and surface protein CD206, indicating a phenotypic shift toward M2-like macrophages for EV-encapsulated scaffolds relative to the other groups. The findings of this study demonstrate that fibroblast-derived EVs integrated into injectable PCL–collagen scaffolds offer a viable, cell-free approach to modulate inflammation, preserve scaffold structure, and support regenerative healing. This strategy holds significant promise for advancing immuno-instructive platforms in regenerative medicine, particularly in settings where conventional cell therapies face limitations in survival, cost, or safety. Full article

Electrospinning has evolved into a vital nanofiber production technique with broad applications across biomedical, environmental, and industrial sectors. Alternating current (AC) and pulsed voltage (PV) electrospinning offer transformative alternatives by utilizing time-varying electric fields to overcome the drawbacks of DC electrospinning by employing an oscillating electric field that facilitates balanced charge dynamics, improved jet stability, and collectorless operation, leading to enhanced fiber alignment and significantly higher production rates, with reports exceeding 20 g/h. Conversely, PV electrospinning applies intermittent high-voltage pulses, offering precise control over jet initiation and termination. This method enables the fabrication of ultrafine, bead-free, and structurally uniform fibers, making it particularly suitable for biomedical applications such as controlled drug delivery and tissue scaffolds. Both techniques support tunable fiber morphology, reduced diameter variability, and improved structural uniformity, contributing to the advancement of high-performance nanofiber materials. This review examines the underlying electrohydrodynamic mechanisms, charge transport behavior, equipment configurations, and performance metrics associated with AC and PV electrospinning. It further highlights key innovations, current limitations in scalability and standardization, and prospective research directions. Full article

Background/Objectives: The utility of various biocompatible biological and synthetic polymers as substrates to provide structural support, facilitate cell migration, and promote the healing of full-thickness wounds by secondary intention has been studied. This includes intelligent structures that enable the release of natural products or drugs for these and other purposes. In this study, the primary objective was to analyze and compare, from a macroscopic perspective, the individual behavior of the polymer poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), with Aloe vera (PHBV/Av) or honey (PHBV/Ho), in the healing process of a full-thickness skin wound over 40 days in a murine model, in addition to describing the microscopic ultrastructure of the nanofibers. Methods: Two experimental groups were established, PHVB/AV (n = 5) and PHVB/Ho (n = 5), along with one control group, PHBV (n = 5), all of which underwent biopsies that included the entire thickness of the skin and the panniculus carnosus of the mid-dorsal area of the mouse. Cylindrical pieces of each membrane, measuring approximately 7 × 0.2 mm, were placed in the wound bed and covered with a transparent dressing. No topical treatment was administered during the control process, nor were the implants changed during the healing period. Results: Univariate and multivariate analyses were performed. The data show that the PHBV/Ho scaffolds reduce the diameter of the wounds by 100% after 40 days (p < 0.001), compared with PHBV/Av (100%; p = 0.211) and the control group, PHBV. Conclusions: From a macroscopic perspective, the PHBV/Ho scaffold significantly accelerated wound healing when applied once to the wound bed, outperforming both the PHBV/Av composite and PHBV alone. Notably, this effect was achieved without the need for dressing changes or additional treatment during the healing period. Full article

Wound healing is a complex biological process that benefits from advanced biomaterials capable of modulating inflammation and promoting tissue regeneration. In this study, cerium oxide nanoparticles (CeO₂NPs) were green-synthesized using Hemerocallis citrina extract, which served as both a reducing and stabilizing agent. The CeO₂NPs exhibited a spherical morphology, a face-centered cubic crystalline structure, and an average size of 9.39 nm, as confirmed by UV-Vis spectroscopy, FTIR, XRD, and TEM analyses. These nanoparticles demonstrated no cytotoxicity and promoted fibroblast migration, while significantly suppressing the production of inflammatory mediators (TNF-α, IL-6, iNOS, NO, and ROS) in LPS-stimulated RAW264.7 macrophages. Gene expression analysis indicated M2 macrophage polarization, with upregulation of Arg-1, IL-10, IL-4, and TGF-β. Aligned polycaprolactone/polylactic acid (PCL/PLA) nanofibers embedded with CeO₂NPs were fabricated using electrospinning. The composite nanofibers exhibited desirable physicochemical properties, including porosity, mechanical strength, swelling behavior, and sustained cerium ions release. In a rat full-thickness wound model, the CeO₂ nanofiber-treated group showed a 22% enhancement in wound closure compared to the control on day 11. Histological evaluation revealed reduced inflammation, enhanced granulation tissue, neovascularization, and increased collagen deposition. These results highlight the therapeutic potential of CeO₂-incorporated nanofiber scaffolds for accelerated wound repair and inflammation modulation. Full article

This review is different from previous studies focusing on polypyrrole (PPy) in universal fields such as sensors and supercapacitors. It is the first TO systematically review the specific applications of PPy-based electrospun nanofiber composites in the biomedical field, focusing on its biocompatibility regulation mechanism and tissue repair function. Although PPy exhibits exceptional electrical conductivity, redox activity, and biocompatibility, its clinical translation is hindered by processing challenges and poor degradability. These limitations can be significantly mitigated through composite strategies with degradable nanomaterials, enhancing both process compatibility and biofunctionality. Leveraging the morphological similarity between electrospun nanofibers and the natural extracellular matrix (ECM), this work comprehensively analyzes the topological characteristics of three composite fiber architectures—randomly distributed, aligned, and core–shell structures—and elucidates their application mechanisms in nerve regeneration, skin repair, bone mineralization, and myocardial tissue reconstruction (e.g., facilitating oriented cell migration and regulating differentiation through specific signaling pathway activation). The study further highlights critical challenges in the field, including PPy’s poor solubility, limited spinnability, insufficient mechanical strength, and scalability limitations. Future efforts should prioritize the development of multifunctional gradient composites, intelligent dynamic-responsive scaffolds, and standardized biosafety evaluation systems to accelerate the substantive translation of these materials into clinical applications. Full article

Nanocellulose obtained from renewable and abundant biomass has garnered significant attention as a sustainable material with exceptional properties and diverse applications. This review explores the key aspects of nanocellulose, focusing on its extraction methods, applications, and future prospects. The synthesis of nanocellulose involves mechanical, chemical, and biological techniques, each uniquely modifying the cellulose structure to isolate cellulose nanocrystals (CNCs), cellulose nanofibers (CNFs), or bacterial nanocellulose (BNC). These methods provide tailored characteristics, enabling applications across a wide range of industries. Nanocellulose’s remarkable properties, including high mechanical strength, large surface area, thermal stability, and biodegradability, have propelled its use in packaging, electronics, biomedicine, and environmental remediation. It has shown immense potential in enhancing the mechanical performance of composites, improving water purification systems, and serving as a scaffold for tissue engineering and drug delivery. However, challenges related to large-scale production, functionalization, regulatory frameworks, and safety concerns persist, necessitating further research and innovation. This review emphasizes the need for sustainable production strategies and advanced functionalization techniques to harness nanocellulose’s full potential. As an eco-friendly, high-performance material, nanocellulose presents a promising avenue for addressing global sustainability challenges while offering transformative solutions for various industries. Full article

Electrospinning is a technique that enables the production of nano- and microfibrillar patterns that mimic the native extracellular matrix. However, these nanofibrous structures often lack mechanical properties suitable for reproducing the behavior of structurally complex tissues. Therefore, achieving more accurate and precise geometric structures be-comes a key challenge. In this context, additive manufacturing techniques such as 3D printing may allow for the development of tailored structures with highly controlled ar-chitecture and improved mechanical strength. However, in contrast with electrospinning, these techniques are commonly considered “low-resolution” techniques, unable to ma-nipulate structural details at the submicrometric scale. Hence, this review aims to intro-duce and discuss recent technological approaches based on combining these technologies for scaffold development in tissue engineering, detailing some distinct integration strate-gies correlating the outcomes to the benefits and drawbacks. Finally, a comprehensive analysis of the current state of the art in the registered intellectual property related to these integrated approaches will be proposed, assessing their distribution by geographic region and analyzing the main trends over time and future fallouts. Full article

Background/Objectives: Polymeric monoaxial nanofibers are gaining prominence due to their numerous applications, particularly in functional scenarios such as wound management. The study successfully developed and built a special-purpose vessel and device for fabricating polymeric nanofibers. Fabrication of composite scaffolds from piezoelectric poly(vinylidenefluoride-trifluoroethylene) copolymer (PVDF-TrFE) nanofibers encapsulated with myrrh extract was investigated. Methods: The gyrospun nanofibers were characterized using SEM, EDX, FTIR, XRD, and TGA to assess the properties of the composite materials. The study also investigated the release profile of myrrh extract from the nanofibers, demonstrating its potential for sustained drug delivery. The composite’s antimicrobial properties were evaluated using the disc diffusion method against various pathogenic microbes, showcasing their effectiveness. Results: It was found that an 18% (w/v) PVDF-TrFE concentration produces the best fiber mats compared to 20% and 25%, resulting in an average fiber diameter of 411 nm. Myrrh extract was added in varying amounts (10%, 15%, and 20%), with the best average fiber diameter identified at 10%, measuring 436 nm. The results indicated that the composite nanofibers were uniform, bead-free, and aligned without myrrh. The study observed a cumulative release of 79.66% myrrh over 72 h. The release profile showed an initial burst release of 46.85% within the first six hours, followed by a sustained release phase. Encapsulation efficiency was 89.8%, with a drug loading efficiency of 30%. Antibacterial activity peaked at 20% myrrh extract. S. mutans was the most sensitive pathogen to myrrh extract. Conclusions: Due to the piezoelectric effect of PVDF-TrFE and the significant antibacterial activity of myrrh, the prepared biohybrid nanofibers will open new avenues toward tissue engineering and wound healing applications. Full article

Background/Objectives: As the incidence of breast cancer increases, reliable, effective, and innovative solutions are required for breast deformities following breast-conserving surgery. We aimed to evaluate the biocompatibility and efficacy of optimized three-dimensional (3D) micro-nanofiber scaffolds and demonstrate their clinical potential through preclinical experiments. Methods: Seven-week-old male Sprague-Dawley rats were randomized into four groups. Group I (control group) received a 2-dimensional (2D) micro-nanofiber scaffold weighing 0.2 g; Groups II–IV received 3D micro-nanofiber scaffolds weighing 0.2, 0.3, and 0.6 g, respectively. These were subcutaneously implanted into the dorsal region and harvested with the surrounding tissues at 4, 8, and 16 weeks for histological evaluation. Results: The number of inflammatory cells was higher in Group IV than in Groups II and III at 4 weeks, with a significant increase in Group IV (p < 0.01) compared with that in Group I. At 8 weeks, it was significantly increased in Group III compared with that in Group I. Furthermore, at 16 weeks, it was significantly reduced in Group IV (p < 0.05) compared with that in Group I. The fibrosis depth in the 3D scaffolds revealed significant differences in Groups II, III, and IV (p < 0.001) compared with Group I at 4 weeks. The collagen fiber densities in the 3D groups were higher than those in the 2D group at 8 and 16 weeks. There were no statistically significant differences between the 3D groups. Conclusions: Absorbable 3D micro-nanofiber scaffolds enhance tissue integration and extracellular matrix formation following post-mastectomy breast reconstruction. Full article

Background/Objectives: Cirsium setosum (commonly known as thistle) is a traditional Chinese medicinal plant with significant therapeutic potential, exhibiting hemostatic, antioxidant, and wound-healing properties. Electrospinning offers a versatile platform for fabricating nanoscale scaffolds with tunable functionality, making them ideal for drug delivery and tissue engineering. Methods: In this study, a bioactive extract from thistle was obtained and incorporated into a thermosensitive triblock copolymer (PNNS) and polycaprolactone (PCL) to develop a multifunctional nanofibrous scaffold for enhanced wound healing. The prepared nanofibers were thoroughly characterized using Fourier-transform infrared spectroscopy (FTIR), contact angle measurements, thermogravimetric analysis (TGA), and tensile fracture testing to assess their physicochemical properties. Results: Notably, the inclusion of PNNS imparted temperature-responsive behavior to the scaffold, enabling controlled deformation in response to thermal stimuli—a feature that may facilitate wound contraction and improve scar remodeling. Specifically, the scaffold demonstrated rapid shrinkage at a physiological temperature (38 °C) within minutes while maintaining structural integrity at ambient conditions (20 °C). In vitro studies confirmed the thistle extract’s potent antioxidant activity, while in vivo experiments revealed their effective hemostatic performance in a liver bleeding model when delivered via the composite nanofibers. Thistle extract and skin temperature-responsive contraction reduced the inflammatory outbreak at the wound site and promoted collagen deposition, resulting in an ideal wound-healing rate of above 95% within 14 days. Conclusions: The integrated strategy that combines mechanical signals, natural extracts, and electrospinning nanotechnology offers a feasible design approach and significant technological advantages with enhanced therapeutic efficacy. Full article

Cellular infiltration into traditional electrospun nanofibers (NFs) is limited due to their dense structures. We were able to obtain polycaprolactone (PCL) NFs with variable and defined pore sizes and thicknesses by using a customized programmed NF collector that controls the moving speed during electrospinning. NFs obtained by this method were tested in vitro and have shown better cell proliferation within the NFs with larger pore sizes. This study investigated in vivo host cell migration and neovascularization within implanted porous PCL NF discs using a mouse pouch model. Four types of PCL NFs were prepared and classified based on the electrospinning speed: NF-zero (static control), NF-low (0.085 mm/min), NF-mid (0.158 mm/min) and NF-high (0.232 mm/min) groups. With the increase in the speed, we observed an increase in the pore area; NF-zero (11.6 ± 6.2 μm²), NF-low (37.4 ± 28.6 μm²), NF-mid (67.6 ± 54.8 μm²), and NF-high (292.3 ± 286.5 μm²) groups. The NFs were implanted into air pouches of BALB/cJ mice. Mice without NFs served as control. Animals were sacrificed at 7 and 28 days after the implantation. Pouch tissues with implanted NFs were collected for histology (n = three per group and time point). The efficiency of the tissue penetration into PCL NF sheets was closely linked to the pore size and area. NFs with the highest pore area had more efficient tissue migration and new blood vessel formation compared to those with a smaller pore area. No newly formed blood vessels were observed in NF-zero sheets up to 28 days. We believe that a porous NF scaffold with a controllable pore size and thickness has great potential for tissue repair/regeneration and for other healthcare applications. Full article

Tension-free hernioplasty has effectively reduced postoperative recurrence and mitigated complications by employing polymer patches. However, clinically used polymer patches often fall short in terms of the anti-deformation, anti-adhesion, and tissue integration functions, which can result in visceral adhesions and foreign body reactions after implantation. In this study, a Janus three-layer composite patch was developed for abdominal wall defect repair using a combination of 3D printing, electrospraying, and electrospinning technologies. On the visceral side, a dense electrospun polyvinyl alcohol/sodium hyaluronate (PVA/HA) scaffold was fabricated to inhibit cell adhesion. The middle layer, composed of polycaprolactone (PCL), provided mechanical support. On the muscle-facing side, a loose and porous electrospun nanofiber scaffold was created through electrospraying and electrospinning, promoting cell adhesion and migration to facilitate tissue regeneration. Mechanical testing demonstrated that the composite patch possessed excellent tensile strength (23.58 N/cm), surpassing the clinical standard (16 N/cm). Both in vitro and in vivo evaluations confirmed the patch’s outstanding biocompatibility. Compared with the control PCL patch, the Janus composite patch significantly reduced the visceral adhesion and enhanced the tissue repair in animal models. Collectively, this Janus composite patch integrated anti-deformation, anti-adhesion, and tissue-regenerative properties, providing a promising solution for effective abdominal wall defect repair. Full article