Electrospun Nanofiber Mats Research Articles

Electrospun PVA nanofiber mat for topical Deflazacort delivery: accentuated anti-inflammatory efficacy for wound healing

Purpose Asses the wound healing activity of Polyvinyl alcohol – Deflazacort (PVA-DEF) nanofibers mats synthesized by electrospinning technology. Methods PVA-DEF nanofiber mats were created with various PVA polymer concentrations using an electrospinning process. The morphological features and diameter of the electrospun nanofibrous mats were investigated using scanning electron microscopy (SEM). The in vitro DEF release rate from PVA electrospun nanofibrous mats was evaluated. In addition to assessing wound healing activity in vivo, histological, and immunochemical tests were conducted. Results Results revealed a uniform and smooth surface of the fiber with an average diameter of the selected fibers of 533.9 nm ± 45.83. Also, PVA electrospun nanofiber mats showed an initial burst release of more than 50% of the DEF in 1 h, and the rest of the DEF was released gradually for up to 480 min. Fickian diffusion is the main DEF release mechanism from PVA electrospun nanofiber mats. In male Wistar albino rats with 1 cm2 excision wounds, in vivo studies revealed a significant improvement in wound healing rate via modulation of tumor necrosis factor-alpha (TNF-α) and vascular endothelial growth factor (VEGF) expression. Conclusion PVA-DEF nanofiber mats can be used effectively for improving wound healing.

Electrospun starch-based nanofiber mats for odor adsorption of oyster peptides: Recyclability and structural characterization

The off-odor of seafood, which negatively affected its flavor and quality, was removed mainly by non-recyclable liquid-phase deodorization methods at present. In this work, octenylsuccinylated starch (OSS)-pullulan (PUL) nanofiber mats were regenerated after physical adsorption and thermal desorption of off-odor compounds in oyster peptides. The mat structure was characterized and the adsorption process was investigated. The regenerated nanofiber mats maintained a favorable appearance and microscopic morphology even after 25 adsorption-desorption cycles, with a reduction in average fiber diameter and average pore area, an increase in hydrophobicity and alterations in surface groups. Their adsorption rate first decreased and then stabilized as the number of cycles increased and was as high as 81.76% after 25 cycles. Correlation analysis revealed that the adsorption efficiency of regenerated nanofiber mats was related to their microstructure, surface groups and hydrophobicity. These findings could provide a theoretical basis for odor removal by electrospun nanofiber mats and their recycling.

Suitability of Mycelium-Reinforced Nanofiber Mats for Filtration of Different Dyes.

Electrospun nanofiber mats have a high specific surface area and very small pores which can be tailored by the spinning process. They are thus highly suitable as filters for small particles and molecules, such as organic dyes. On the other hand, they are usually very thin and thus have low mechanical properties. As a potential reinforcement, mycelium of Pleurotus ostreatus was grown on poly(acrylonitrile) nanofiber mats and thermally solidified after fully covering the nanofiber mats. This study investigates whether the filtration efficiency of the nanofiber mats is altered by the mycelium growing through it and whether the mechanical properties of the nanofibrous filters can be improved in this way. The study shows fast and reliable growth of the mycelium on the nanofiber mats and high filtration efficiency for astra blue and chlorophyll, while indigo carmine showed only very low filtration efficiency of up to 20%. For chlorophyll and safranin, membranes with mycelium showed higher filtration than pure nanofiber mats. In diffusion cell tests, especially astra blue was strongly adsorbed on the membranes with mycelium.

Piezoelectric-based bioactive zinc oxide-cellulose acetate electrospun mats for efficient wound healing: an in vitro insight.

Being a complex physiological process involving the removal of damaged tissue debris and creating a new microenvironment for host tissue regeneration, wound healing is still a major challenge for healthcare professionals. Disruption of this process can lead to tissue inflammation, pathogenic infections, and scar formation. Current wound healing treatments primarily focus on passive tissue healing, lacking active engagement in the healing process. In recent years, a new class of functional biomaterials based on piezoelectric properties has emerged, which can actively participate in the wound healing process by harnessing mechanical forces generated from body movement. Herein, we have fabricated a bioactive Cellulose Acetate (CA) electrospun nanofibrous mat incorporating zinc oxide (ZnO) and investigated its efficiency for accelerated wound healing. We have characterized the physicochemical properties of the fabricated nanofibrous mats using various assays, including SEM, FTIR, TGA, mechanical testing, degradation analysis, porosity measurement, hemolysis assay, and piezoelectric d33 coefficient measurement. Through our investigation, we discovered the tunned piezoelectric coefficient of fabricated specimens due to incorporating ZnO into the CA fibers. In vitro studies also confirmed enhanced cell adhesion, proliferation, and migration, indicating faster wound healing potential. Overall, our findings support the efficacy of piezoelectric-based ZnO-incorporated bioactive CA nanofibrous mats for efficient wound healing.

Electrospun Nanofiber Mats with Embedded Zinc Oxysulfide for Photoreduction of Nitrobenzene to Aniline under Mild Condition.

In this work, electrospun nanofiber embedded with zinc oxysulfide (Zn(O,S)) has been demonstrated as an efficient and robust photocatalyst for hydrogenation of nitrobenzene to aniline under solar light irradiation at mild conditions with methanol as the hole scavenger. The solid solution state of Zn(O,S) in electrospun nanofiber was successfully revealed by high-resolution transmission electron microscopy and X-ray diffraction analyses in which the lattice fringes and diffraction planes located in between those of ZnO and ZnS phases. Moreover, the electrochemical and optical properties of Zn(O,S) embedded in polyethylene oxide (PEO) nanofiber are found to be better than those of ZnO and ZnS indicating more efficient photocatalytic activities as well. The photocatalytic hydrogenation of nitrobenzene to aniline occurred completely within 2 h of the photocatalytic reaction with a reusability of 95% after five consecutive runs. Finally, the mechanism of photocatalytic hydrogenation by Zn(O,S) embedded in the PEO (PZOS) nanofiber involves a total of six electrons (e-) and six protons (H+) to hydrogenate nitrobenzene to nitrosobenzene, phenylhydroxylamine, and aniline.

The effect of κ-carrageenan and ursolic acid on the physicochemical properties of the electrospun nanofibrous mat for biomedical application

Wound dressing materials such as nanofiber (NF) mats have gained a lot of attention in recent years owing to their wonderful effect on accelerating the healing process and protection of wounds. In this regard, three different types of NF mats were fabricated using pure polyvinylpyrrolidone (PVP), PVP/κ-carrageenan (KG), and ursolic acid (UA) in the optimal PVP/KG ratio by electrospinning method to apply them as wound dressings. The morphology, chemical structure, degradation, porosity, mechanical properties and antioxidant activity of the produced NFs were investigated. Moreover, cell studies (e.g., cell proliferation, adhesion, and migration) and their antibacterial properties were evaluated. Adding KG and UA reduced the mean diameter size of the PVP-based NFs to ∼98 nm in the optimal sample, with defect-free morphology. The PVP/KG/UA 0.25 % exhibited the highest porosity, hydrophilicity, and degradation rate and a wound closure rate of 60 %, 2.5 times higher than that of the control group. Furthermore, this sample's proliferation and antibacterial ability were significantly higher than the other groups. These findings confirmed that the produced UA-loaded NFs have excellent properties as wound dressing.

Homogeneity of Needleless Electrospun Nanofiber Mats.

Nanofiber mats can be electrospun by different techniques, usually subdivided into needle-based and needleless. The latter allow for producing large-area nanofiber mats, e.g., with a width of 50 cm and lengths of several meters, if electrospinning proceeds for several hours, depending on the required thickness. Even spinning smaller samples, however, raises the question of homogeneity, especially if defined mechanical properties or a defined thickness is required, e.g., for filtration purposes. Very often, only the inner parts of such electrospun nanofiber mats are used to avoid too high variation of the nanofiber mat thickness. For this study, we used wire-based electrospinning to prepare nanofiber mats with slightly varying spinning parameters. We report investigations of the thickness and mass per unit area, measured on different positions of needleless electrospun nanofiber mats. Martindale abrasion tests on different positions are added as a measure of the mechanical properties. All nanofiber mats show unexpectedly strong variations of thickness, mass per unit area, and porosity, as calculated from the apparent density of the membranes. The thickness especially varied by nearly one order of magnitude within one sample, while the apparent density, as the most uniform parameter, still showed variations by more than a factor of two within one sample. This shows that even for apparently highly homogeneous areas of such nanofiber mats, variations cannot be neglected for all potential applications.

PH-sensitive bilayer electrospun nanofibers based on ethyl cellulose and Eudragit S-100 as a dual delivery system for treatment of the burn wounds; preparation, characterizations, and in-vitro/in-vivo assessment

A pH-sensitive bilayer electrospun nanofibrous mat containing both antibiotic (gentamicin sulfate, GEN) and non-steroidal anti-inflammatory (diclofenac sodium, DIC) drugs was fabricated for burn wound dressing by electrospinning technique, in which ethyl cellulose (EC) and ethyl cellulose/Eudragit S-100 (EC/ES-100) formed the top and bottom layers, respectively. The fabricated pH-sensitive bilayer electrospun nanofibrous mats were characterized from aspects of both structure and efficiency. Physicochemical properties were investigated via SEM, FTIR, and TGA. The swelling ratio and in vitro drug release of the fabricated nanofibrous mats were studied in different pHs. MTT was applied to assess the safety of the fiber mats. Finally, the in vivo efficiency of the designed pH-sensitive bilayer electrospun nanofibrous mats was examined on the male Wistar rats. Based on the histological analysis and wound healing test (in vivo animal experiments), the (ES100/EC-DIC/GEN)-(EC) pH-sensitive bilayer nanofibrous mat displayed faster wound healing than other bilayer nanofibrous mat. As a result, (ES100/EC-DIC/GEN)-(EC) bilayer nanofibrous mat with pH-responsion could accelerate the burn wound healing process via decreasing the adverse effects of GEN and DIC as topical antimicrobial and anti-inflammatory agents, receptively.

Electrospun nanofiber composite mat based on ulvan for wound dressing applications

Wound dressings can be used to create a temporary healing environment and expedite the wound healing process. Ulvan (ULV) is a sulfated polysaccharide with potent antiviral and anti-inflammatory activities. Polycaprolactone (PCL) is a hydrophobic biodegradable polyester that exhibits slow degradation, strong mechanical strength, and excellent biocompatibility. Electrospun nanofiber matrices mimic the microstructure of the extracellular matrix, allowing them to promote cell proliferation and differentiation. Therefore, the primary objective of this study was to fabricate a polycaprolactone-ulvan fibrous composite mat (PCL-ULV) using the electrospinning technique and to investigate its physical and chemical properties. To assess the characteristics of PCL-ULV, scanning electron microscopy (SEM) was utilized to examine its morphology and diameter distribution. Fourier transform infrared (FTIR) spectroscopy, calcofluor white staining, and monosaccharide analysis were employed to analyze the components of PCL-ULV. Additionally, the water contact angle was measured to evaluate the hydrophilicity. Furthermore, the proliferation and morphology of and gene expression in NIH3T3 fibroblasts on PCL-ULV were assessed. The results showed that the average PCL-ULV fiber diameter was significantly smaller than that of the PCL fibers. The water contact angle measurements indicated that PCL-ULV exhibited better hydrophilicity than the PCL mat. FTIR, calcofluor white staining, and monosaccharide analyses demonstrated that ULV could be successfully coelectrospun with PCL. NIH3T3 fibroblasts cultured on PCL and PCL-ULV showed different cellular behaviors. On PCL-ULV, cell adhesion, proliferation, and stretching were greater than those on PCL. Moreover, the behavior of NIH3T3 fibroblasts on PCL and PCL-ULV differed, as the cells on PCL-ULV exhibited higher proliferation and more stretching. Furthermore, NIH3T3 fibroblasts cultured on ULV-PCL showed higher α-SMA and MMP-9 gene expression and a lower ratio of TIMP-1/MMP-9 than those cultured on PCL. Notably, scarless wounds display lower TIMP/MMP expression ratios than scarring wounds. Thus, the fibrous composite mat PCL-ULV shows potential as a wound dressing for scarless wound healing.

Electrospun Nanofiber Membranes with Various Structures for Wound Dressing.

Electrospun nanofiber membranes (NFMs) have high porosity and a large specific surface area, which provide a suitable environment for the complex and dynamic wound healing process and a large number of sites for carrying wound healing factors. Further, the design of the nanofiber structure can imitate the structure of the human dermis, similar to the natural extracellular matrix, which better promotes the hemostasis, anti-inflammatory and healing of wounds. Therefore, it has been widely studied in the field of wound dressing. This review article overviews the development of electrospinning technology and the application of electrospun nanofibers in wound dressings. It begins with an introduction to the history, working principles, and transformation of electrospinning, with a focus on the selection of electrospun nanofiber materials, incorporation of functional therapeutic factors, and structural design of nanofibers and nanofiber membranes. Moreover, the wide application of electrospun NFMs containing therapeutic factors in wound healing is classified based on their special functions, such as hemostasis, antibacterial and cell proliferation promotion. This article also highlights the structural design of electrospun nanofibers in wound dressing, including porous structures, bead structures, core-shell structures, ordered structures, and multilayer nanofiber membrane structures. Finally, their advantages and limitations are discussed, and the challenges faced in their application for wound dressings are analyzed to promote further research in this field.

Fabrication of affinity-based drug delivery systems based on electrospun chitosan sulfate/poly(vinyl alcohol) nanofibrous mats

Benign electrospinning of chitosan in aqueous medium is an open challenge mainly due to its insolubility in neutral pH and inter- and intramolecular hydrogen bonding interactions. Here, we developed a simple and widely-used methodology to improve the chitosan electrospinnability through the sulfation of chitosan and its further mixing with poly(vinyl alcohol) for the first time. The FTIR, 1H NMR and elemental analyses showed the successful sulfation of chitosan. Furthermore, the viscosity and electrical conductivity measurements revealed the high solubility of chitosan sulfate (CS) in aqueous media. In the next step, a uniform electrospun nanofibrous mat of CS/PVA was fabricated with a fiber diameter ranging from 90 to 340 nm. The crosslinked CS/PVA (50/50) nanofibrous mat as the optimum sample showed a swelling ratio of 290 ± 4 % and a high Young's modulus of 3.75 ± 0.10 GPa. Finally, malachite green (MG) as a cationic drug model was loaded into different samples of chitosan film, CS film, and CS/PVA (50/50) nanofibrous mat and its release behavior was studied. The results of these analyses revealed that the CS/PVA (50/50) nanofibrous mat can successfully load higher contents of the MG and also release it in a sustained manner.

Electrospun Nanofiber Materials for Photothermal Interfacial Evaporation.

Photothermal interfacial evaporation with low cost and environmental friendliness has attracted much attention. However, there are still many problems with this technology, such as heat loss and salt accumulation. Due to their different structures and adjustable chemical composition, electrospun nanofiber materials generally exhibit some unique properties that provide new approaches to address the aforementioned issues. In this review, the rational design principles for improving the total efficiency of solar evaporation are described for thermal/water management systems and salt-resistance strategies. And we review the state-of-the-art advancements in photothermal evaporation based on nanofiber materials and discuss their derivative applications in desalination, water purification, and power generation. Finally, we highlight key challenges and opportunities in both fundamental research and practical applications to inform further developments in the field of interfacial evaporation.

A Review: Electrospinning Applied to Solar Interfacial Evaporator

The emerging solar interfacial evaporation (SIE) technology is an effective measure to address freshwater resources. An efficient and stable solar interfacial evaporator cannot be achieved without the synergy of three key factors: water transport, solar thermal conversion, and thermal management. The performance of a solar interfacial evaporator can be improved through the rational selection of materials and the structural design of these three key factors. Due to superior nanostructures, electrospun nanofibrous materials often exhibit some unique properties that facilitate the construction of solar interface evaporators with good performance. So far, electrospinning has been used to prepare structures such as solar absorbers, water transportation, and thermal insulation in various solar interfacial evaporators. This review presents the fundamental research and technological development in the application of electrospinning techniques to solar interfacial evaporators on structures, morphology, and properties. Then, the latest advances in the use of electrospinning technology in solar interfacial evaporators are summarized and the current issues facing the application of electrospinning technology to solar interfacial evaporators are presented. These systematic discussions can provide ideas and approaches for the rational design of electrospun nanofiber materials for solar interfacial evaporators in the future.

Digital ink‐jet printing of regenerated cellulose nanofibrous mats with reactive inks

AbstractThe versatility of nanofibres enables them to be used for various technological applications such as filtration, biomedicine and healthcare, composites, protective and functional textiles. Recently, in addition to the functional properties of electrospun nanofibrous mats, their aesthetic properties have been explored. Herein, attempts have been made to develop digital ink‐jet printing of regenerated cellulose nanofibrous mats with reactive inks. First, a cellulose acetate polymer was created to fabricate electrospun cellulose acetate nanofibrous mats, which were then converted into regenerated cellulose nanofibrous mats through deacetylation. Next, the cellulose nanofibrous mats were treated with an alkaline solution then coloured with four (cyan, magenta, yellow and black) commercially available reactive inks by a digital ink‐jet printing method using a piezoelectric digital ink‐jet printer. Various parameters were investigated, including the optimal concentration of the pretreatment agents, fixation temperature and time, colour yield and the absorbency of the electrospun nanofibrous mats. The digital ink‐jet printed cellulose nanofibrous mats exhibited excellent colour yield and colour fastness properties. Morphological analysis through scanning electron microscopy and chemical analysis through Fourier Transform–infrared were also carried out.

Fabrication of PLA-Based Electrospun Nanofibers Reinforced with ZnO Nanoparticles and In Vitro Degradation Study.

In this work, electrospun nanofibers based on polylactic acid, PLA, reinforced with ZnO nanoparticles have been studied, considering the growing importance of electrospun mats based on biopolymers for their applications in different fields. Specifically, electrospun nanofibers based on PLA have been prepared by adding ZnO nanoparticles at different concentrations, such as 0.5, 1, 3, 5, 10 and 20 wt%, with respect to the polymer matrix. The materials have been characterized in terms of their morphological, mechanical, and thermal properties, finding 3 wt% as the best concentration to produce PLA nanofibers reinforced with ZnO nanoparticles. In addition, hydrolytic degradation in phosphate buffer solution (PBS) was carried out to study the effect of ZnO nanoparticles on the degradation behavior of PLA-based electrospun nanofiber mats, obtaining an acceleration in the degradation of the PLA electrospun mat.

Preparation and characterization of drug-loaded, electrospun nanofiber mats formulated with zein or zein-based mixtures for wound healing applications.

Electrospun zein mats are known to have poor mechanical and water uptake properties limiting their usefulness as wound dressings.
 In this study, the effects of the solvent system used, the incorporation of the polymeric additives; polyethylene glycol 20000 (PEG20K) and polyvinylpyrrolidone K30 (PVPK30); and the crosslinking agent Tannic Acid (TA) on the mechanical and water uptake characteristics of zein – based nanofiber mats were investigated.
 The incorporation of either PEG20K or PVPK30 resulted in an improvement in water vapor sorption and a reduction in water contact-angle of the nanofiber mats. In addition, the incorporation of PEG20K and PVPK30 reduced the ultimate tensile strength, and Young’s modulus while increasing the percent elongation of the nanofiber mats. The use of tannic acid as a crosslinking agent led to an increase in the water vapor sorption, ultimate tensile strength, and Young’s modulus of the nanofiber mats.
 Mats with smaller average fiber diameter, greater ultimate tensile strength, higher Young's modulus, and greater water vapor sorption were obtained when using 80% (v/v) aqueous ethanol as a solvent system during the preparation of the nanofiber mats when compared to those produced using 60% (v/v) aqueous ethanol. In addition, using solutions with lower zein concentration resulted in mats with lower average fiber diameter, lower ultimate tensile strength and Young’s modulus, and higher percent elongation.
 Selected formulations were loaded with tetracycline hydrochloride and drug release was evaluated in bulk liquid and using Franz diffusion cells. The use of Franz diffusion cells allowed the discrimination between formulation performance as a function of composition and water uptake properties. Drug release from nanofiber mats was also confirmed by observing the formation of an inhibition zone in cultures of E. coli and S. aureus using the agar diffusion assay.
 Improved performance of zein nanofiber mats was achieved using polymeric modifiers and crosslinking with tannic acid improving their suitability for wound dressing applications.

Effect of Recombinant Spidroins Self-Assembly on Rheological Behavior of Their Dispersions and Structure of Electrospun Nanofibrous Materials.

The effect of primary amino acid sequence in recombinant spidroins on their spatial organization is crucial for the fabrication of artificial fibers and fibrous materials. This study focuses on the rheological properties of aqueous and alcoholic solutions of recombinant analogs of natural spidroins (rS1/9 and rS2/12), as well as the structure of their films and nanofibrous materials. Non-Newtonian flow behavior of aqueous solutions of these proteins was observed at certain concentrations in contrast to their solutions in hexafluoroisopropanol. The secondary structure of recombinant spidroins was addressed by IR spectroscopy, whereas their self-organization in various solvents was studied by AFM and cryo-TEM. The influence of the solvent on the structure and properties of the films and nanofibrous materials produced by electrospinning has been established.

Dielectric and Magneto-dielectric properties of GdFeO3 modified PbTiO3 nanofibrous mats obtained through electrospinning technique

This study intends to create and analyze electrospun nanofibrous mats of GdFeO3 doped PbTiO3 i.e Pb0.8Gd0.2Ti0.8Fe0.2O3 (GF-PT) using sol gel method. The polyvinylpyrrolidone PVP/GF-PT material was attempted to generate a highly viscous sol that is used to transform into nanofibers utilizing various parameters. The crystallographic parameters were estimated using X-ray diffraction (XRD) patterns, which supported single phase tetragonal structure. Also, Scherer equation was used to calculate the typical nanocrystallite size of the manufactured nanofibrous mats, and the result was 15.92 nm. The morphological investigations showed that a variety of factors, such as applied voltage, flow rate, and needle-collector distance, had a significant impact on the average diameter of nanofibrous mats. The nanofibers displayed ferromagnetic behavior and exhibited residual magnetism of approximately 0.0257 emu/g. The created nanofibers exhibit significant magneto-electric (ME) coupling characteristics having the highest magneto-dielectric response (MDR) at 1.2 T of about −38.62 % and the calculated magneto- dielectric coefficient value is −275.05 emu2/g2.

Fabrication of ɛ-Polylysine-Loaded Electrospun Nanofiber Mats from Persian Gum-Poly (Ethylene Oxide) and Evaluation of Their Physicochemical and Antimicrobial Properties.

In the present study, electrospun nanofiber mats were fabricated by mixing different ratios (96:4, 95:5, 94:6, 93:7, and 92:8) of Persian gum (PG) and poly (ethylene oxide) (PEO). The SEM micrographs revealed that the nanofibers obtained from 93% PG and 7% PEO were bead-free and uniform. Therefore, it was selected as the optimized ratio of PG:PEO for the development of antimicrobial nanofibers loaded with ɛ-Polylysine (ɛ-PL). All of the spinning solutions showed pseudoplastic behavior and the viscosity decreased by increasing the shear rate. Additionally, the apparent viscosity, G', and G″ of the spinning solutions increased as a function of PEO concentration, and the incorporation of ɛ-PL did not affect these parameters. The electrical conductivity of the solutions decreased when increasing the PEO ratio and with the incorporation of ɛ-PL. The X-ray diffraction (XRD) and Fourier-transform infrared (FTIR) spectra showed the compatibility of polymers. The antimicrobial activity of nanofibers against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus) was investigated, and the samples loaded with ɛ-PL demonstrated stronger antimicrobial activity against S. aureus.

Nanofiber matrix formulations for the delivery of Exendin-4 for tendon regeneration: In vitro and in vivo assessment.

Tendon and ligament injuries are the most common musculoskeletal injuries, which not only impact the quality of life but result in a massive economic burden. Surgical interventions for tendon/ligament injuries utilize biological and/or engineered grafts to reconstruct damaged tissue, but these have limitations. Engineered matrices confer superior physicochemical properties over biological grafts but lack desirable bioactivity to promote tissue healing. While incorporating drugs can enhance bioactivity, large matrix surface areas and hydrophobicity can lead to uncontrolled burst release and/or incomplete release due to binding. To overcome these limitations, we evaluated the delivery of a peptide growth factor (exendin-4; Ex-4) using an enhanced nanofiber matrix in a tendon injury model. To overcome drug surface binding due to matrix hydrophobicity of poly(caprolactone) (PCL)-which would be expected to enhance cell-material interactions-we blended PCL and cellulose acetate (CA) and electrospun nanofiber matrices with fiber diameters ranging from 600 to 1000nm. To avoid burst release and protect the drug, we encapsulated Ex-4 in the open lumen of halloysite nanotubes (HNTs), sealed the HNT tube endings with a polymer blend, and mixed Ex-4-loaded HNTs into the polymer mixture before electrospinning. This reduced burst release from ∼75% to ∼40%, but did not alter matrix morphology, fiber diameter, or tensile properties. We evaluated the bioactivity of the Ex-4 nanofiber formulation by culturing human mesenchymal stem cells (hMSCs) on matrix surfaces for 21 days and measuring tenogenic differentiation, compared with nanofiber matrices in basal media alone. Strikingly, we observed that Ex-4 nanofiber matrices accelerated the hMSC proliferation rate and elevated levels of sulfated glycosaminoglycan, tendon-related genes (Scx, Mkx, and Tnmd), and ECM-related genes (Col-I, Col-III, and Dcn), compared to control. We then assessed the safety and efficacy of Ex-4 nanofiber matrices in a full-thickness rat Achilles tendon defect with histology, marker expression, functional walking track analysis, and mechanical testing. Our analysis confirmed that Ex-4 nanofiber matrices enhanced tendon healing and reduced fibrocartilage formation versus nanofiber matrices alone. These findings implicate Ex-4 as a potentially valuable tool for tendon tissue engineering.