Electrospun Nanofiber Scaffolds Research Articles

Application and Development of Electrospun Nanofiber Scaffolds for Bone Tissue Engineering.

Nanofiber scaffolds have gained significant attention in the field of bone tissue engineering. Electrospinning, a straightforward and efficient technique for producing nanofibers, has been extensively researched. When used in bone tissue engineering scaffolds, electrospun nanofibers with suitable surface properties promote new bone tissue growth and enhance cell adhesion. Recent advancements in electrospinning technology have provided innovative approaches for scaffold fabrication in bone tissue engineering. This review comprehensively examines the utilization of electrospun nanofibers in bone tissue engineering scaffolds and evaluates the relevant literature. The review begins by presenting the fundamental principles and methodologies of electrospinning. It then discusses various materials used in the production of electrospun nanofiber scaffolds for bone tissue engineering, including natural and synthetic polymers, as well as certain inorganic materials. The challenges associated with these materials are also described. The review focuses on novel electrospinning techniques for scaffold construction in bone tissue engineering, such as multilayer nanofibers, multifluid electrospinning, and the integration of electrospinning with other methods. Recent advancements in electrospinning technology have enabled the fabrication of precisely aligned nanofiber scaffolds with nanoscale architectures. These innovative methods also facilitate the fabrication of biomimetic structures, wherein bioactive substances can be incorporated and released in a controlled manner for drug delivery purposes. Moreover, they address issues encountered with traditional electrospun nanofibers, such as mechanical characteristics and biocompatibility. Consequently, the development and implementation of novel electrospinning technologies have revolutionized scaffold fabrication for bone tissue engineering.

Enhancing surface morphology, mechanical, and wettability properties of PVA/chitosan/HAp nanofiber scaffold through dielectric barrier discharge plasma treatment

Dielectric barrier discharge (DBD) plasma treatment has been widely used for surface functionalization, allowing for precise modification of surface chemistry and morphology. This study investigates the efficacy of DBD plasma treatment in enhancing the surface morphology and wettability of electrospun nanofiber scaffolds composed of polyvinyl alcohol (PVA), chitosan, and hydroxyapatite (HAp), with potential applications in bone tissue engineering. Scanning electron microscopy (SEM) revealed significant alterations in surface morphology after treatment, including a reduction in average fiber diameter and the presence of uneven, damaged, and even broken fibers. Interestingly, the ultimate strength of the nanofibers increased from 1.13 ± 0.05 MPa to 6.99 ± 0.07 MPa despite the decrease in diameter. Contact angle measurements confirmed a remarkable improvement in wettability, with the contact angle decreasing from 39.46° to 7.45° following increasing treatment time. This enhanced wettability suggests improved cell adhesion, potentially leading to more effective bone tissue regeneration.

Citrus flavonoids-loaded chitosan derivatives-route nanofilm as drug delivery systems for cutaneous wound healing

This study focuses on creating new forms of biomimetic nanofiber composites by combining copolymerizing and electrospinning approaches in the field of nanomedicine. The process involved utilizing the melt polymerization of proline (Pr) and hydroxyl proline (Hyp) to synthesize polymers based on Pr (PPE) and Hyp (PHPE). These polymers were then used in a grafting copolymerization process with chitosan (CS) to produce PHPC (1560 ± 81.08 KDa). A novel electrospun nanofiber scaffold was then produced using PHPC and/or CS, hyaluronic acid, polyvinyl alcohol, and naringenin (NR) as a loading drug. Finally, Mouse Dermal Fibroblast (MDF) cells were introduced to the wound dressing and assessed their therapeutic potential for wound healing in rats. The scaffolds were characterized by FTIR, NMR, DSC, and SEM analysis, which confirmed the amino acid grafting, loading drug, and porous and nanofibrous structures (>225 nm). The results showed that the PHPC-based scaffolds were more effective for swelling/absorption of wound secretions, had more elasticity/elongation, faster drug release, more MDF-cytocompatibility, and antibacterial activity against multidrug-resistant S. aureus compared to CS-based scaffolds. The in vivo studies showed that NR in combination with MDF can accelerate cell migration/proliferation, and remodeling phases of wound healing in both PHPC/CS-based scaffolds. Moreover, PHPC-based scaffolds promote collagen content, and better wound contraction, epithelialization, and neovascularization than CS-based, showing potential as wound-dressing.

Electrospun Nanofiber Scaffold for Skin Tissue Engineering: A Review.

Skin tissue engineering (STE) is widely regarded as an effective approach for skin regeneration. Several synthetic biomaterials utilized for STE have demonstrated favorable fibrillar characteristics, facilitating the regeneration of skin tissue at the site of injury, yet they have exhibited a lack of in situ degradation. Various types of skin regenerative materials, such as hydrogels, nanofiber scaffolds, and 3D-printing composite scaffolds, have recently emerged for use in STE. Electrospun nanofiber scaffolds possess distinct advantages, such as their wide availability, similarity to natural structures, and notable tissue regenerative capabilities, which have garnered the attention of researchers. Hence, electrospun nanofiber scaffolds may serve as innovative biological materials possessing the necessary characteristics and potential for use in tissue engineering. Recent research has demonstrated the potential of electrospun nanofiber scaffolds to facilitate regeneration of skin tissues. Nevertheless, there is a need to enhance the rapid degradation and limited mechanical properties of electrospun nanofiber scaffolds in order to strengthen their effectiveness in soft tissue engineering applications in clinical settings. This Review centers on advanced research into electrospun nanofiber scaffolds, encompassing preparation methods, materials, fundamental research, and preclinical applications in the field of science, technology, and engineering. The existing challenges and prospects of electrospun nanofiber scaffolds in STE are also addressed.

AI-Driven Optimization of PCL/PEG Electrospun Scaffolds for Enhanced In Vivo Wound Healing.

Here, an artificial intelligence (AI)-based approach was employed to optimize the production of electrospun scaffolds for in vivo wound healing applications. By combining polycaprolactone (PCL) and poly(ethylene glycol) (PEG) in various concentration ratios, dissolved in chloroform (CHCl3) and dimethylformamide (DMF), 125 different polymer combinations were created. From these polymer combinations, electrospun nanofiber meshes were produced and characterized structurally and mechanically via microscopic techniques, including chemical composition and fiber diameter determination. Subsequently, these data were used to train a neural network, creating an AI model to predict the optimal scaffold production solution. Guided by the predictions and experimental outcomes of the AI model, the most promising scaffold for further in vitro analyses was identified. Moreover, we enriched this selected polymer combination by incorporating antibiotics, aiming to develop electrospun nanofiber scaffolds tailored for in vivo wound healing applications. Our study underscores three noteworthy conclusions: (i) the application of AI is pivotal in the fields of material and biomedical sciences, (ii) our methodology provides an effective blueprint for the initial screening of biomedical materials, and (iii) electrospun PCL/PEG antibiotic-bearing scaffolds exhibit outstanding results in promoting neoangiogenesis and facilitating in vivo wound treatment.

Fabrication of Quercetin-Functionalized Morpholine and Pyridine Motifs-Laden Silk Fibroin Nanofibers for Effective Wound Healing in Preclinical Study.

Choosing suitable wound dressings is crucial for effective wound healing. Spun scaffolds with bioactive molecule functionalization are gaining attention as a promising approach to expedite tissue repair and regeneration. Here, we present the synthesis of novel multifunctional quercetin with morpholine and pyridine functional motifs (QFM) embedded in silk fibroin (SF)-spun fibers (SF-QFM) for preclinical skin repair therapies. The verification of the novel QFM structural arrangement was characterized using ATR-FTIR, NMR, and ESI-MS spectroscopy analysis. Extensive characterization of the spun SF-QFM fibrous mats revealed their excellent antibacterial and antioxidant properties, biocompatibility, biodegradability, and remarkable mechanical and controlled drug release capabilities. SF-QFM mats were studied for drug release in pH 7.4 PBS over 72 h. The QFM-controlled release is mainly driven by diffusion and follows Fickian's law. Significant QFM release (40%) occurred within the first 6 h, with a total release of 79% at the end of 72 h, which is considered beneficial in effectively reducing bacterial load and helping expedite the healing process. Interestingly, the SF-QFM-spun mat demonstrated significantly improved NIH 3T3 cell proliferation and migration compared to the pure SF mat, as evidenced by the complete migration of NIH 3T3 cells within 24 h in the scratch assay. Furthermore, the in vivo outcome of SF-QFM was demonstrated by the regeneration of fresh fibroblasts and the realignment of collagen fibers deposition at 9 days post-operation in a preclinical rat full-thickness skin defect model. Our findings collectively indicate that the SF-QFM electrospun nanofiber scaffolds hold significant capability as a cost-effective and efficient bioactive spun architecture for use in wound healing applications.

An Apparatus for Measuring Combined Shear-Tensile Loading in Fibrous Tissues Ex Vivo.

Soft tissues such as tendon and ligament undergo a combination of shear and tensile loading in vivo due to their boundary conditions at muscle and/or bone. Current experimental protocols are limited to pure tensile loading, biaxial loading, or simple shear, and thus may not fully characterize the mechanics of these tissues under physiological loading scenarios. Our objective was to create an experimental protocol to determine the shear modulus of fibrous tissues at different tensile loads. We assembled a four-actuator experimental system that facilitated shear deformation to be superimposed on a tissue subjected to an axial preload. We measured shear modulus in axially loaded electrospun nanofiber scaffolds with either randomly oriented or aligned fibers. We found that shear modulus in the nanofiber phantoms was shear-strain stiffening and dependent on both the axial load (p < 0.001) and fiber alignment (p < 0.001) of the scaffold. The proposed system can enhance our understanding of microstructure and functional mechanics in soft tissues, while also providing a platform to investigate the behavior of electrospun scaffolds for tissue regeneration. Our experimental protocol for determining loaded shear modulus would be further useful as a method to gauge tissue mechanics under loading conditions that are more representative of physiological loads applied to tendon and ligament.

Burn wound healing using adipose-derived mesenchymal stem cells and manganese nanoparticles in polycaprolactone/gelatin electrospun nanofibers in rats

Introduction: Wound healing is a major therapeutic concern in regenerative medicine. The current study aimed to investigate the second-degree burn wound treatment in rats using rat adipose- derived stem cells (ADSCs) and manganese nanoparticles (MnO2–NPs) in a polycaprolactone/gelatin electrospun nanofiber scaffold. Methods: After the synthesis of nanoparticles and electrospinning of nanofibers, the SEM analysis, contact angle, mechanical strength, blood compatibility, porosity, swelling, biodegradability, cell viability, and adhesion assays were performed. According to the results, the PCL/Gel/5%MnO2-NPs nanofiber (Mn-5%) was determined to be the most suitable scaffold. The ADSCs-seeded Mn-5% scaffolds were applied as a burn wound dressing. The wound closure rate, IL-1β, and IL-6 level, hydroxyproline, and glycosaminoglycans content were measured, and the hematoxylin and eosin, Masson’s trichrome, and immunohistochemistry stainings were carried out. Results: Based on the results, in Mn+S (ADSCs+PCL/Gel/5%MnO2-NPs nanofiber) and N+S (ADSCs+PCL/Gel nanofiber) groups, the IL-6 and IL-1β levels were reduced, and the percentage of wound closure, glycosaminoglycans, and hydroxyproline content were increased compared to the control group (P&lt;0.05). Also, the lowest amount of α-SMA was observed in these two groups, demonstrating stem cells' role in reducing α-SMA levels and thus preventing fibrosis. Moreover, the amount of α-SMA in the Mn+S group is lower than in the N+S group and, is closer to healthy skin. According to histology results, the best type of treatment was observed in the Mn+S group. Conclusion: In conclusion, the ADSCs-seeded PCL/Gel/5%MnO2-NPs scaffold demonstrated considerable therapeutic effects in burn wound healing.

Electrospun Nanofiber Scaffolds Loaded with Metal-Based Nanoparticles for Wound Healing.

Failures of wound healing have been a focus of research worldwide. With the continuous development of materials science, electrospun nanofiber scaffolds loaded with metal-based nanoparticles provide new ideas and methods for research into new tissue engineering materials due to their excellent antibacterial, anti-inflammatory, and wound healing abilities. In this review, the stages of extracellular matrix and wound healing, electrospun nanofiber scaffolds, metal-based nanoparticles, and metal-based nanoparticles supported by electrospun nanofiber scaffolds are reviewed, and their characteristics and applications are introduced. We discuss in detail the current research on wound healing of metal-based nanoparticles and electrospun nanofiber scaffolds loaded with metal-based nanoparticles, and we highlight the potential mechanisms and promising applications of these scaffolds for promoting wound healing.

Engineering of electrospun nanofiber scaffolds for repairing brain injury

Engineering of electrospun nanofiber scaffolds for repairing brain injury

Pumpkin Seed Oil ‐Loaded Chitosan/Polyvinyl Alcohol Electrospun Nanofiber Scaffold for Dermal and Oral Wound Dressing

AbstractPumpkin seed oil was combined with polyvinyl alcohol (PVA) and chitosan (CS) to develop novel electrospun nanofibers that can serve as wound scaffolds. The main objective of this work is to evaluate the safety, drug release, and performance of these scaffolds for dermal and oral wound healing. The scaffolds were characterized using a field scanning electron microscope (FSEM), and Fourier transform infrared spectroscopy (FTIR). A series of tests were conducted, including the degree of swelling and degradation, in vitro drug release, antibacterial activity, and cytotoxicity in human dermal fibroblasts adult (HDFa). Wound healing activity in an excisional dermal and incisional oral wound's rat model was evaluated after 10 days. Antibacterial tests of the Pumpkin loaded CS/PVA nanofibers showed significant antibacterial activity against S. aureus and E. coli compared to negative controls. In vivo dermal wound healing showed that all treatment groups enhanced wound healing, as demonstrated by the increased wound closure percentages compared to negative control groups on 3, 5, and 10 days. Compared to other treatment groups, pumpkin‐loaded CS/PVA nanofibers significantly enhanced healing on 7 and 10 days, however, healing was delayed afterward. In oral wound healing, the qualitative Hematoxylin and Eosin (H−E) histological examination of the oral wounds treated with pumpkin‐loaded scaffolds showed an enhanced healing rate with healthy architecture compared to the wounds treated with unloaded scaffolds or untreated wounds. These results indicate that Pumpkin loaded nanofibers are promising for both dermal and oral wound healing. They offer a new safe and cheap alternative to the commercial treatments that are used for wound healing. The results also highlight the combination of using natural botanical compounds and emerging nanoscience for biomedical applications, primarily wound healing.

Fabrication and multiscale modeling of polycaprolactone/amniotic membrane electrospun nanofiber scaffolds for wound healing.

Enhancing the efficiency of cell-based skin tissue engineering (TE) approaches is possible via designing electrospun scaffolds possessing natural materials like amniotic membrane (AM) with wound healing characteristics. Concentrating on this aim, we fabricated innovative polycaprolactone (PCL)/AM scaffolds through the electrospinning process. The manufactured structures were characterized by employing scanning electron microscope (SEM), attenuated total reflection-Fourier transform infrared (ATR-FTIR) spectroscopy, tensile testing, Bradford protein assay, etc. In addition, the mechanical properties of scaffolds were simulated by the multiscale modeling method. As a result of conducting various tests, it was concluded that the uniformity and distribution of fibers decreased with an increase in the amniotic content. Furthermore, PCL-AM scaffolds contained amniotic and PCL characteristic bands. In the case of protein release, greater content of AM led to the release of higher amounts of collagen. Tensile testing revealed that scaffolds' ultimate strength increased when the AM content augmented. The multiscale modeling demonstrated that the scaffold had elastoplastic behavior. In order to assess cellular attachment, viability, and differentiation, human adipose-derived stem cells (ASCs) were seeded on the scaffolds. In this regard, SEM and 3-(4,5-dimethylthiazol-2-yl)-2,5-diphenyl-2H-tetrazolium bromide (MTT) assays showed significant cellular proliferation and viability on the proposed scaffolds, and these analyses illustrated that higher cell survival and adhesion could be achieved when scaffolds possessed a larger amount of AM. After 21 days of cultivation, particular keratinocyte markers, such as keratin I and involucrin, were identified through utilizing immunofluorescence and real-time polymerase chain reaction (PCR) tests. The markers' expressions were higher in the PCL-AM scaffold with a ratio of 90:10 v v-1 compared with the PCL-epidermal growth factor (EGF) structure. Moreover, the presence of AM in the scaffolds resulted in the keratinogenic differentiation of ASCs even without employing EGF. Consequently, this state-of-the-art experiment suggests that the PCL-AM scaffold can be a promising candidate in skin bioengineering. This study showed that mixing AM with PCL, a widely used polymer, in different concentrations can overcome PCL disadvantages such as high hydrophobicity and low cellular compatibility.

PLGA/Gelatin-based electrospun nanofiber scaffold encapsulating antibacterial and antioxidant molecules for accelerated tissue regeneration

A full-thickness or hard-to-heal wound pose a significant challenge in clinical feilds. These wounds are very prone to microbial infection, lead to an elevated level of reactive oxygen species, and require a skin regeneration product for rapid healing. Considering these issues, we developed ciprofloxacin hydrochloride and quercetin encapsulated PLGA/Gelatin based electrospun nanofibers for wound healing. Morphology and diameter of nanofibers were determined by SEM. FT-IR and powder-XRD was used to determine any possible physic-chemical interaction and change in the crystalline property of drugs, respectively. In-vitro swelling ratio and weight loss was measured to simulate in-vivo degradation pattern of scaffold. High drugs entrapment with a bi-phasic sustained release profile was observed in phosphate buffer (pH =7.4). DPPH scavenging potential and antibacterial activity against S. aureus on agar plate were utilized to evaluate antioxidant and antibacterial properties. The biocompatibility of developed nanofiber was assessed by MTT assay using 3T6-Swiss albino fibroblast and hemocompatibility assay using harvested erythrocytes from human blood. After excising full-thickness wounds in Wistar rats, the healing efficacies of nanofiber were evaluated, this showed accelerated healing with complete re-epithelialization within 16 days. Hematoxylin & eosin staining and hydroxyproline assay confirmed the in-vivo wound healing observation. These findings support the use of ciprofloxacin hydrochloride and quercetin-loaded PLGA/Gelatin based nanofiber as a dressing material for full-thickness wounds.

Fabrication of a Polycaprolactone/Chitosan Nanofibrous Scaffold Loaded with Nigella sativa Extract for Biomedical Applications

In this study, biocompatible electrospun nanofiber scaffolds were produced using poly(-caprolactone (PCL)/chitosan (CS) and Nigella sativa (NS) seed extract, and their potential for biomedical applications was investigated. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), total porosity measurements, and water contact angle measurements were used to evaluate the electrospun nanofibrous mats. Additionally, the antibacterial activities of Escherichia coli and Staphylococcus aureus were investigated, as well as cell cytotoxicity and antioxidant activity, using MTT and DPPH assays, respectively. The obtained PCL/CS/NS nanofiber mat was observed by SEM to have a homogeneous and bead-free morphology, with average diameters of 81.19 ± 4.38 nm. Contact angle measurements showed that the wettability of the electrospun PCL/Cs fiber mats decreased with the incorporation of NS when compared to the PCL/CS nanofiber mats. Efficient antibacterial activity against S. aureus and E. coli was displayed, and an in vitro cytotoxic assay demonstrated that the normal murine fibroblast cell line (L929 cells) remained viable after 24, 48, and 72 h following direct contact with the produced electrospun fiber mats. The results suggest that the PCL/CS/NS hydrophilic structure and the densely interconnected porous design are biocompatible materials, with the potential to treat and prevent microbial wound infections.

Design and development of biodegradable POSS-PCL-Zeolite (β) nano-scaffold for potential applications in bone regeneration

Side effects caused by bone fractures and restrictions on bone regeneration impose an enormous economic burden on the health system of society. To overcome these limitations, tissue engineering and cell-based therapies have been proposed as alternatives to induce and promote bone healing. Still, bone regeneration disadvantages, such as limited and painful surgery, the risk of infection, nerve injury, bleeding, and function damage, have led investigators to find an alternative therapy. In some studies, bone stimulants have prompted scientists to design scaffolds with appropriate physical structure with the possibility of cell adhesion and proliferation, which plays an influential role in the regeneration and repair of bone tissue. PCL nanofiber is an absorbing candidate for the formulation of biocompatible scaffolds used in tissue engineering. To overcome these negative aspects, improve the properties of PCL nanofibers, and based on the biocompatibility and superior mechanical properties of POSS, Polyhedral Oligomeric Silsesquioxane-Polycaprolactone-Zeolite (POSS-PCL-Zeolite) nanocomposite electrospun nanofiber scaffolds were fabricated in the present study. Nanohybrids and nanofibers structures were characterized by FTIR, HNMR, XRD, SEM, EDX, and DSC techniques. We used cellular and molecular assays, including DCFH ROS detection system, gene expression (RUNX-2, Osteocalcin, Nrf2, BAX, VEGF gens), and apoptotic to demonstrate the biocompatibility and induce bone differentiation of formulated POSS-PCL-Zeolite scaffolds. The results showed the biodegradability of POSS-PCL-Zeolite Nano-scaffold and supported the nesting of mesenchymal stem cells (MSCs) and induced bone differentiation by POSS-PCL-Zeolite Nano-scaffold.

Investigating of physical, mechanical, and biological properties of polyhydroxybutyrate-keratin/alumina electrospun scaffold utilized in bone tissue engineering

Electrospun nanofiber scaffolds have a similar structure to extracellular matrix, leading to increased cell adhesion, proliferation, and migration. In this study, 1–5wt % of alumina nanowires were added to polyhydroxybutyrate-keratin (PHB–K) solution, and the morphology of the electrospun scaffolds in terms of fiber diameter, porosity percentage, and the uniformity of the alumina nanowires distribution was evaluated by SEM. FTIR and raman tests were also used to evaluate the chemical bonds of nanofibers and the presence of alumina and keratin in electrospun scaffolds. The crystallinity of the scaffolds was also measured using DSC and confirmed by XRD. The increase of alumina augmented the crystallinity of scaffolds because alumina is a nucleating agent. The tensile strength of PHB-K scaffolds increased up to 3 fold in the presence of 3 wt % of alumina.The MG63 cells survived, and the secretion of alkaline phosphatase and mineralization due to the presence of alumina was significantly higher than PHB and PHB-K scaffolds. Based on the results, the electrospun PHB-K/AL2O3 scaffolds are potential candidates for bone tissue engineering.

Human iPS-derived blood-brain barrier model exhibiting enhanced barrier properties empowered by engineered basement membrane

The basement membrane (BM) of the blood-brain barrier (BBB), a thin extracellular matrix (ECM) sheet underneath the brain microvascular endothelial cells (BMECs), plays crucial roles in regulating the unique physiological barrier function of the BBB, which represents a major obstacle for brain drug delivery. Owing to the difficulty in mimicking the unique biophysical and chemical features of BM in in vitro systems, current in vitro BBB models have suffered from poor physiological relevance. Here, we describe a highly ameliorated human BBB model accomplished by an ultra-thin ECM hydrogel-based engineered basement membrane (nEBM), which is supported by a sparse electrospun nanofiber scaffold that offers in vivo BM-like microenvironment to BMECs. BBB model reconstituted on a nEBM recapitulates the physical barrier function of the in vivo human BBB through ECM mechano-response to physiological relevant stiffness (∼500 kPa) and exhibits high efflux pump activity. These features of the proposed BBB model enable modelling of ischemic stroke, reproducing the dynamic changes of BBB, immune cell infiltration, and drug response. Therefore, the proposed BBB model represents a powerful tool for predicting the BBB permeation of drugs and developing therapeutic strategies for brain diseases.

Evaluation of PCL Electrospun Scaffolds Concentration on Metformin Hydrochloride Release Ratio

The study investigates the effect of polycaprolactone (PCL) concentration on the metformin hydrochloride (MH) release ratio of electrospun nanofiber scaffolds. Blend and emulsion electrospinning are used to produce the scaffolds. The performance of nanofibrous scaffolds was evaluated by morphology (Field Emission Scanning Electron Microscopy, FESEM), chemical (Fourier Transform Infrared Spectroscopy, FTIR), thermal (Differential Scanning Calorimetry, DSC), wettability, porosity, mechanical tests, and in vitro drug release. The average fiber diameter ranged from (189.29-2893.93 nm) according to the FESEM results, and it increased with PCL concentration. The average fiber diameter of the electrospun scaffold, prepared by the blend method (259.64±6.1 nm), is lower than that of the electrospun scaffold produced by the emulsion method (487.45±22.53 nm). Melting points of all drug-loaded scaffolds were identical to those of pure PCL polymer. Compared with blend electrospun nanofibers, emulsion electrospun nanofibers showed a marked increase in hydrophilicity. The tensile strength indicated an improvement in the mechanical properties with a decrease in the average fiber diameter. Moreover, the results show that the release of Metformin hydrochloride decreases with the concentration of polycaprolactone. Total MH release from (5% w/v) PCL-MH fibrous scaffolds for three-week was 71.11 % and 93.91 % from the emulsion and blend methods, respectively. The drug release ratio is lower in emulsion electrospinning than in blend because the drug is encapsulated by polymer and surfactant, which improves control and long-term drug delivery system DDS.

Hybrid electrospun scaffold loaded with Argireline acetate and Dexpanthenol for skin regeneration

Tissue engineering provides novel methods for a wide variety of skin injuries, among which, the electrospun nanofibers have attracted special attention for wound dressing fabrications. In this research, we have fabricated scaffolds based on Poly l-lactic acid (PLLA) and Polyethylene oxide (PEO) polymers and have loaded the hybrid PLLA/PEO with active substances, Argireline and Dexpanthenol. The five categories of nanofiber scaffolds were prepared by electrospinning: (1) PLLA, (2) PLLA/PEO hybrid scaffold, (3) PLLA/PEO hybrid scaffold loaded with Argireline (PLLA/PEO/A), (4) PLLA/PEO hybrid scaffold loaded with Dexpanthenol (PLLA/PEO/D), (5) PLLA/PEO hybrid scaffold loaded with Argireline and Dexpanthenol (PLLA/PEO/A/D). Our SEM analysis of the electrospun nanofibers shows that all nanofibers are bead-free and are in the range of 200–600 nm. The static water contact angle measurements via the sessile drop method have shown a transition from a hydrophobic surface for the PLLA scaffold (CA = 118.43 ± 1.6°) to a hydrophilic surface for PLLA/PEO hybrid scaffold (CA = 35.5 ± 2.8°). The addition of Argireline, Dexpanthenol, and a mixture of both has been shown to improve this wettability even further. The electrospun nanofiber scaffolds were further analyzed for their air permeability, and mechanical properties. The cytocompatibility analysis indicated superior performance for PLLA/PEO loaded with both Argireline and Dexpanthenol. The in-vivo analysis was conducted on the second-degree burn rat models in six different studied groups: 1-healthy rat, 2-negative control, and rats treated with 3-PLLA/PEO, 4-PLLA/PEO/A, 5-PLLA/PEO/D, and 6-PLLA/PEO/A/D. The wound area reduction was assessed on day 3, day 7, and day 14 in all groups along with the histology analysis based on hematoxylin/eosin. Our results show that rats treated with PLLA/PEO/A/D not only have a great reduction in the wound area, but their histology analysis demonstrates high angiogenesis and collagen formation, and epithelialization. We believe the existence of both active substances has a synergic effect on the wound healing process.

Integrating Inflammation-Responsive Prodrug with Electrospun Nanofibers for Anti-Inflammation Application.

Chronic inflammation plays a side effect on tissue regeneration, greatly inhibiting the repair or regeneration of tissues. Conventional local delivery of anti-inflammation drugs through physical encapsulation into carriers face the challenges of uncontrolled release. The construction of an inflammation-responsive prodrug to release anti-inflammation drugs depending on the occurrence of inflammation to regulate chronic inflammation is of high need. Here, we construct nanofiber-based scaffolds to regulate the inflammation response of chronic inflammation during tissue regeneration. An inflammation-sensitive prodrug is synthesized by free radical polymerization of the indomethacin-containing precursor, which is prepared by the esterification of N-(2-hydroxyethyl) acrylamide with the anti-inflammation drug indomethacin. Then, anti-inflammation scaffolds are constructed by loading the prodrug in poly(ε-caprolactone)/gelatin electrospun nanofibers. Cholesterol esterase, mimicking the inflammation environment, is adopted to catalyze the hydrolysis of the ester bonds, both in the prodrug and the nanofibers matrix, leading to the generation of indomethacin and the subsequent release to the surrounding. In contrast, only a minor amount of the drug is released from the scaffold, just based on the mechanism of hydrolysis in the absence of cholesterol esterase. Furthermore, the inflammation-responsive nanofiber scaffold can effectively inhibit the cytokines secreted from RAW264.7 macrophage cells induced by lipopolysaccharide in vitro studies, highlighting the great potential of these electrospun nanofiber scaffolds to be applied for regulating the chronic inflammation in tissue regeneration.