Self-powered portable melt electrospinning for in situ wound dressing

Biocompatible Native Hyaluronan Nanofibers Fabricated via Aqueous PEO-Assisted Electrospinning and Heat-Quench Process

Hyaluronan (HA) is widely used in cosmetic and biomedical applications due to its excellent biocompatibility and potential to promote wound healing. Nanofibrous HA, mimicking the extracellular matrix (ECM), is considered promising for therapeutic and cosmetic applications. However, the electrospinning process of HA often necessitates cytotoxic solvents and chemical modifications, compromising its biocompatibility and advantageous properties. In this study, poly(ethylene oxide) (PEO) was added to an aqueous solution of natural HA to improve its spinnability, enabling HA to be electrospun into fibers. The HA was rendered water-insoluble by treatment with an acidic solution, and the amorphized PEO, achieved by heat-quenching, was removed through water washing. This method distinguishes it from previous reports of fibers blended with PEO or other water-soluble polymers. Consequently, the resulting HA gel fibers demonstrated suitability for mesenchymal stem cell adhesion due to the exposure of HA on the fiber surface. Additionally, HA fibers were successfully applied directly onto the skin using a hand-held electrospinning device, indicating the potential for point-of-care and home use applications.

Recent advances of electrospun strategies in topical products encompassing skincare and dermatological treatments

As the potential applications of electrospinning in healthcare continue to be explored, along with advancements in industrial-scale solutions and the emergence of portable electrospinning devices, some researchers have explored electrospinning technology in topical products, including its application in skincare, such as facial masks, beauty patches, sunscreen, and dermatological treatments for conditions like atopic dermatitis, psoriasis, acne, skin cancer, etc. In this review, we first outline the fundamental principles of electrospinning and provide an overview of existing solutions for large-scale production and the components and functionalities of portable spinning devices. Based on the essential functionalities required for skincare products and the mechanisms and treatment methods for the aforementioned dermatological diseases, we summarize the potential advantages of electrospinning technology in these areas, including encapsulation, sustained release, large surface area, and biocompatibility, among others. Furthermore, considering the further commercialization and clinical development of electrospinning technology, we offer our insights on current challenges and future perspectives in these areas, including issues such as ingredients, functionality, residue concerns, environmental impact, and efficiency issues.

Recent advances in harnessing biological macromolecules for wound management: A review

Wound dressings (WDs) are an essential component of wound management and serve as an artificial barrier to isolate the injured site from the external environment, thereby helping to prevent exogenous infections and supporting healing. However, maintaining a moist wound environment, providing protection from infection, good biocompatibility, and allowing for gas exchange, remain a challenge in device design. Functional wound dressings (FWDs) prepared from hybrid biological macromolecule-based materials can enhance efficacy of these systems for skin wound management. This review aims to provide an overview of the state-of-the-art FWDs within the field of wound management, with a specific focus on hybrid biomaterials, techniques, and applications developed over the past five years. In addition, we highlight the incorporation of biological macromolecules in WDs, the emergence of smart WDs, and discuss the existing challenges and future prospects for the development of advanced WDs.

Carboxymethyl chitosan and polycaprolactone-based rapid in-situ packaging for fruit preservation by solution blow spinning

Nanofiber packaging has not yet gained practical application in fruit preservation because of some limitations, such as low production rate and utilization, and failure due to poor adhesion to the fruit. Herein, to solve this issue, a novel fruit packaging method based on solution blow spinning (SBS), called in-situ packaging, was pioneered. Specifically, carboxymethyl chitosan (CMCH) and polycaprolactone (PCL) were chosen as substrate materials and cherry tomatoes were selected as demonstration subjects. CMCH/PCL nanofibers were deposited directly onto the surface of cherry tomatoes by SBS, forming a tightly adherent and stable fiber coating in 8 min. Also, this in-situ packaging could be easily peeled off by hand. The in-situ packaging was an excellent carrier for active substances and was effective in inhibiting gray mold on cherry tomatoes. The in-situ packaging film formed a barrier on the surface of cherry tomatoes to limit moisture penetration, resulting in reduced respiration of fruits, which led to reduced weight and firmness loss. In addition, metabolomics and color analysis revealed that the in-situ packaging delayed ripening of cherry tomatoes after harvest. Overall, the in-situ packaging method developed in the present work provides a new solution for post-harvest fruit preservation.

In Situ Precision Cell Electrospinning as an Efficient Stem Cell Delivery Approach for Cutaneous Wound Healing

Mesenchymal stem cell (MSC) therapies have been brought forward as a promising treatment modality for cutaneous wound healing. However, current approaches for stem cell delivery have many drawbacks, such as lack of targetability and cell loss, leading to poor efficacy of stem cell therapy. To overcome these problems, in the present study, an in situ cell electrospinning system is developed as an attractive approach for stem cell delivery. MSCs have a high cell viability of over 90% even with a high applied voltage of 15 kV post-cell electrospinning process. In addition, cell electrospinning does not show any negative effect on the surface marker expression and differentiation capacity of MSCs. In vivo studies demonstrate that in situ cell electrospinning treatment can promote cutaneous wound healing through direct deposition of bioactive fish gelatin fibers and MSCs onto wound sites, leading to a synergic therapeutic effect. The approach enhances extracellular matrix remodeling by increasing collagen deposition, promotes angiogenesis by increasing the expression of vascular endothelial growth factor (VEGF) and forming small blood vessels, and dramatically reduces the expression of interleukin-6 (IL-6) during wound healing. The use of in situ cell electrospinning system potentially provides a rapid, no touch, personalized treatment for cutaneous wound healing.

Antibacterial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG) development for its potential use in bioactive wound dressings

An adequate wound dressing reduces time of healing, provides cost-effective care, thereby improving patients' quality life. An antimicrobial bioactivity is always desired, for that reason, the objective of this work is to design an antimicrobial nanocomposite of chitosan/silver nanocrystals/graphene oxide (ChAgG). ChAgG nanostructured composite material is composed of chitosan from corn (Ch), and silver nanocrystals from garlic (Allium sativum). The nanocomposite obtained is the result of a series of experiments combining the graphene oxide (GrOx) with two members of the Amaryllidaceae family; garlic and onion (Allium cebae), which contain different sulfur materials. The characterization arrays confirmed the successful production of silver crystal, graphene oxidation and the blending of both components. The role of the chitosan as a binder between graphene and silver nanocrystals is proved. Moreover, the study discusses garlic as an optimal source that permits the synthesis of silver nanocrystals (AgNCs) (⁓ 2 to 10 nm) with better thermal and crystallinity properties. It was also confirmed the successful production of the ChAgG nanocomposite. Escherichia coli and Staphylococcus aureus were used to demonstrate the antibacterial bioactivity and L-929 fibroblast cells were utilized to visualize their biocompatibility. The proposed ChAgG nanomaterial will be useful for functionalizing specific fiber network that represents current challenging research in the fabrication of bioactive wound dressings.

In-Time Detection of Plant Water Status Change by Self-Adhesive, Water-Proof, and Gas-Permeable Electrodes

Leaf capacitance can reflect plant water content. However, the rigid electrodes used in leaf capacitance monitoring may affect plant health status. Herein, we report a self-adhesive, water-proof, and gas-permeable electrode fabricated by in situ electrospinning of a polylactic acid nanofiber membrane (PLANFM) on a leaf, spraying a layer of the carbon nanotube membrane (CNTM) on PLANFM, and in situ electrospinning of PLANFM on CNTM. The electrodes could be self-adhered to the leaf via electrostatic adhesion due to the charges on PLANFM and the leaf, thus forming a capacitance sensor. Compared with the electrode fabricated by a transferring approach, the in situ fabricated one did not show obvious influence on plant physiological parameters. On that basis, a wireless leaf capacitance sensing system was developed, and the change of plant water status was detected in the first day of drought stress, which was much earlier than direct observation of the plant appearance. This work paved a useful way to realize noninvasive and real-time detection of stress using plant wearable electronics.

Highly hygroscopicity and antioxidant nanofibrous dressing base on alginate for accelerating wound healing

The removal of bacterium and free radicals is important for wound healing. Therefore, it is necessary to prepare biological dressings with antibacterial and antioxidant properties. In this study, high-performance calcium alginate/carbon polymer dots/forsythin composite nanofibrous membrane (CA/CPDs/FT) was explored under the influence of carbon polymer dots and forsythin. The addition of carbon polymer dots improved the nanofiber morphology and therefore enhanced the mechanical strength of the composite membrane. Moreover, CA/CPDs/FT membranes displayed satisfactory antibacterial and antioxidant properties because of the natural properties of forsythin. Meanwhile, outstanding hygroscopicity over 700% was also obtained for the composite membrane. In vitro and in vivo experiments showed that the CA/CPDs/FT nanofibrous membrane could prevent the invasion of bacteria, scavenge free radicals, and promote wound healing. Moreover, its good hygroscopicity and antioxidation characteristics were friendly for the clinical application of high-exudate wounds.

Bottom-Up Strategy to Forecast the Drug Location and Release Kinetics in Antitumoral Electrospun Drug Delivery Systems

Electrospun systems are becoming promising devices usable for topical treatments. They are eligible to deliver different therapies, from anti-inflammatory to antitumoral. In the current research, polycaprolactone electrospun membranes loaded with synthetic and commercial antitumoral active substances were produced, underlining how the matrix-filler affinity is a crucial parameter for designing drug delivery devices. Nanofibrous membranes loaded with different percentages of Dacarbazine (the drug of choice for melanoma) and a synthetic derivative of Dacarbazine were produced and compared to membranes loaded with AuM1, a highly active Au-complex with low affinity to the matrix. AFM morphologies showed that the surface profile of nanofibers loaded with affine substances is similar to one of the unloaded systems, thanks to the nature of the matrix-filler interaction. FTIR analyses proved the efficacy of the interaction between the amidic group of the Dacarbazine and the polycaprolactone. In AuM1-loaded membranes, because of the weak matrix-filler interaction, the complex is mainly aggregated in nanometric domains on the nanofiber surface, which manifests a nanometric roughness. Consequently, the release profiles follow a Fickian behavior for the Dacarbazine-based systems, whereas a two-step with a highly prominent burst effect was observed for AuM1 systems. The performed antitumoral tests evidence the high-cytotoxic activity of the electrospun systems against melanoma cell lines, proving that the synthetic substances are more active than the commercial dacarbazine.

Thermally Treated Berberine-Loaded SA/PVA/PEO Electrospun Microfiber Membranes for Antibacterial Wound Dressings

This study aimed to develop a safe and advanced antibacterial material of electrospun microfiber membranes (MFMs) for wound dressings. Combinations of several materials were investigated; thermal treatment and electrospinning techniques were used to form the best quality of MFMs to suit its end applications. By comparing the fiber morphology, diameter changes, and fracture strength, the suitable ratio of raw materials and thermal treatment were obtained before and after adding Trition X-100 as a surfactant for MFMs of sodium alginate/polyvinyl alcohol/polyethylene oxide (SA/PVA/PEO). The electrospinning solution was mixed with berberine as an antibacterial substance; meanwhile, calcium chloride (CaCl₂) was used as the crosslinking agent. The antibacterial properties, water dissolution resistance, water content, and fracture strength were thoroughly investigated. The results showed that the antibacterial rates of MFMs with different mass fractions of berberine (0, 3, and 5 wt.%) to Escherichia coli (E. coli) were 14.7, 92.9, and 97.2%, respectively. The moisture content and fracture strength of MFMs containing 5 wt.% berberine were 72.0% and 7.8 MPa, respectively. In addition, the produced MFMs embodied great water dissolution resistance. Berberine-loaded SA/PVA/PEO MFMs could potentially serve as an antibacterial wound dressing substrate with low cost and small side effects.

Characteristics and Safety Profiles of a Hydrocolloid Polyester Dressing Incorporated with Herbal Extract: In Vitro, in Vivo and Randomized Clinical Studies

The polyester dressing containing herbal extract had been used for several years. However, some properties had not been investigated. This study examined three parts including in vitro studies, skin irritation in an animal model, and the pilot clinical study in traumatic wounds. In in vitro studies, six different wound dressings consisted of hydrocolloid polyester containing herbal extract (SI-HERB®), hydrofiber (Aquacel®), hydrocolloid polyester (Urgotul®), soft paraffin gauze (Bactigras®), foam (Mepilex®), and biocellulose (Suprasorb® X + PHMB) dressings were comparatively evaluated in physical properties including the fluid absorption, desorption, and fluid drainage ability. The skin irritation test was examined in a rabbit model using SI-HERB® as a tested group. In a clinical study, traumatic patients with leg wounds were randomly assigned to six wound dressings. The primary outcome was the pain level and the secondary outcomes were non-adherence and peri-wound reaction evaluating score. From the study, Bactigras® had the largest pore size but the total area of pore size per field of it was similar to SI-HERB®. There were no significant differences between SI-HERB®, Urgotul®, and Bactigras® in the percentage of absorption and desorption. No dermatologic effect was found in the animal study. In the irritation test on leg wounds, pain level, and peri-wound reaction in hydrocolloid polyester dressing group were significantly lower compared with Aquacel® and Bactigras®. The polyester dressing had the pain level after removal lower than before application while the Mepilex® and Suprasorb® presented that insignificantly increase the pain level. Erythema could be observed in Bactigras®, Aquacel®, and Suprasorb® but the edema scores were not different. A hydrocolloid polyester dressing containing herbal extract had good drainage ability. No skin irritation was reported. Pain scores, removal ability, and peri-wound reaction were also significantly lower with other types of wound dressings. These results suggested that this dressing be an alternative in wound treatment.

Gelatin-based nanofiber membranes loaded with curcumin and borneol as a sustainable wound dressing

Infection is a huge obstacle to wound healing. Thus, to enhance the healing of infected wounds, wound dressings that permit the dual delivery of antimicrobials and antioxidants are highly desirable. In this study, a series of gelatin-based nanofiber membranes with different curcumin contents were fabricated via solution electrospinning. The obtained membranes were characterized in terms of their morphologies, in addition to their physical, mechanical, and in vitro properties. The results showed that the membranes maintained an integrated morphology, excellent water absorption capability, satisfactory mechanical properties, and a high dissolution rate of curcumin. The addition of curcumin and borneol conferred the membranes the ability to inhibit Staphylococcus aureus and eliminate free radicals. Furthermore, cytocompatibility testing using the L929 cell line confirmed the excellent biocompatibility of the membranes. These gelatin-based nanofiber membranes loaded with curcumin and borneol can therefore be considered as promising materials for dressing wounds. Moreover, the use of biodegradable polymers and environmentally sustainable production techniques in this system render it suitable for the commercial manufacture of composite membranes.

Rational Design of Intelligent and Multifunctional Dressing to Promote Acute/Chronic Wound Healing

Currently, the clinic's treatment of acute/chronic wounds is still unsatisfactory due to the lack of functional and appropriate wound dressings. Intelligent and multifunctional dressings are considered the most advanced wound treatment modalities. It is essential to design and develop wound dressings with required functions according to the wound microenvironment in the clinical treatment. This work summarizes microenvironment characteristics of various common wounds, such as acute wound, diabetic wound, burns wound, scalded wound, mucosal wound, and ulcers wound. Furthermore, the factors of transformation from acute wounds to chronic wounds were analyzed. Then we focused on summarizing how researchers fully and thoroughly combined the complex microenvironment with modern advanced technology to ensure the usability and value of the dressing, such as photothermal-sensitive dressings, microenvironment dressing (pH-sensitive dressings, ROS-sensitive dressings, and osmotic pressure dressings), hemostatic dressing, guiding tissue regeneration dressing, microneedle dressings, and 3D/4D printing dressings. Finally, the revolutionary development of wound dressings and how to transform the existing advanced functional dressings into clinical needs as soon as possible have carried out a reasonable and meaningful outlook.

An overview on electrospinning and its advancement toward hard and soft tissue engineering applications

One of the emerging technologies of the recent times harboring nanotechnology to fabricate nanofibers for various biomedical and environmental applications are electrospinning (nanofiber technology). Their relative ease in use, simplicity, functionality and diversity has surpassed the pitfalls encountered with the conventional method of generating fibers. This review aims to provide an overview of electrospinning, principle, methods, feed materials, and applications toward tissue engineering. To begin with, evolution of electrospinning and its typical apparatus have been briefed. Simultaneously, discussion on the production of nanofibers with diversified feed materials such as polymers, small molecules, colloids, and nanoparticles and its transformation into a powerful technology has been dealt with. Further, highlights on the application of nanofibers in tissue engineering and the commercialized products developed using nanofiber technology have been summed up. With this rapidly emerging technology, there would be a great demand pertaining to scalability and environmental challenge toward tissue engineering applications.

New Forms of Electrospun Nanofibers Applied in Cardiovascular Field

Cardiovascular disease (CVD) is one of the leading causes of death worldwide. In recent years, regenerative medicine, tissue engineering and the development of new materials have become the focus of attention this field, and electrospinning technology to prepare nanofibrous materials for the treatment of cardiovascular diseases has attracted people's attention. Unlike previous reviews, this research enumerates the experimental methods and applications of electrospinning technology combined with nanofibrous materials in the directions of myocardial infarction repair, artificial heart valves, artificial blood vessels and cardiovascular patches from the perspective of cardiovascular surgery. In the end, this review also summarizes the limitations, unresolved technical challenges, and possible future directions of this technology for cardiovascular disease applications.

Nanofibrous Membrane with Encapsulated Glucose Oxidase for Self-Sustained Antimicrobial Applications

Polyvinyl alcohol (PVA) nanofibrous membrane, consisting of separately encapsulated glucose oxidase (GOx) and glucose (Glu) nanofibers, was prepared via simultaneously electrospinning PVA/GOx and PVA/Glu dopes. The as-prepared pristine membrane could self-sustainably generate hydrogen peroxide (H2O2) only in contact with an aqueous solution. The H2O2 production level was well maintained even after storing the dry membrane at room temperature for 7 days. Cross-linking the membrane via reaction with glutaraldehyde (GA) vapor could not only prevent the nanofibrous membrane from dissolving in water but also prolonged the release of H2O2. The sustained release of H2O2 from the membrane achieved antimicrobial capability equivalent to that of 1% H2O2 against both Escherichia coli and Staphylococcus aureus. Gram(+) S. aureus cells were more susceptible to H2O2 than Gram(-) E. coli and >99% of S. aureus were killed after 1 h incubation with the membrane. Pristine and GA-crosslinked nanofibrous membrane with in situ production of H2O2 were self-sterilized in which no microorganism contamination on the membrane could be detected after 2 weeks incubation on an agar plate. The GOx/Glu membrane may find potential application as versatile antimicrobial materials in the field of biomedicine, in the food and health industries, and especially challenges related to wound healing in diabetic patients.

Instant in-situ Tissue Repair by Biodegradable PLA/Gelatin Nanofibrous Membrane Using a 3D Printed Handheld Electrospinning Device

Background: This study aims to design a 3D printed handheld electrospinning device and evaluate its effect on the rapid repair of mouse skin wounds.

Methods: The device was developed by Solidworks and printed by Object 350 photosensitive resin printer. The polylactic acid (PLA)/gelatin blend was used as the raw material to fabricate in-situ degradable nanofiber scaffolds. Scanning electron microscopy (SEM), Fourier transform infrared spectroscopy (FTIR), X-ray diffraction (XRD), and water vapor permeability test were used to evaluate the material properties of the scaffolds; cytotoxicity test was performed to evaluate material/residual solvent toxicity, and in situ tissue repair experiments in Balb/c mouse were performed.

Results: The 3D printed handheld electrospinning device successfully fabricates PLA/gelatin nanofibrous membrane with uniformly layered nanofibers and good biocompatibility. Animal experiments showed that the mice in the experimental group had complete skin repair.

Conclusions: The 3D printed handheld device can achieve in situ repair of full-thickness defects in mouse skin.

Preparation and Physicochemical Characterization of a Diclofenac Sodium-Dual Layer Polyvinyl Alcohol Patch

The aim of this study is to prepare a dual layer polyvinyl (PVA) patch using a combination of electrospinning techniques and cryogelation (freeze-thaw process) then subsequently to investigate the effect of freeze-thaw cycles, nanofiber thickness, and diclofenac sodium (DS) loading on the physicochemical and mechanical properties and formulation of dual layer PVA patches composed of electrospun PVA nanofibers and PVA cryogel. After the successful preparation of the dual layer PVA patch, the prepared patch was subjected to investigation to assess the effect of freeze-thaw cycles, nanofiber thickness and percentages of DS loading on the morphology, physiochemical and mechanical properties. Various spectroscopic techniques such as scanning electron microscopy (SEM), X-ray diffraction (XRD), Fourier transform infrared (FTIR), water contact angle, and tensile tests were used to evaluate the physicochemical and mechanical properties of prepared dual layer PVA patches. The morphological structures of the dual layer PVA patch demonstrated the effectiveness of both techniques. The effect of freeze-thaw cycles, nanofiber thickness, and DS percentage loading on the crystallinity of a dual layer PVA patch was investigated using XRD analysis. The presence of a distinct DS peak in the FTIR spectrum indicates the compatibility of DS in a dual layer PVA patch through in-situ loading. All prepared patches were considered highly hydrophilic because the data obtained was less than 90°. The increasing saturation of DS within the PVA matrix increases the tensile strength of prepared patches, however decreased its elasticity. Evidently, the increasing of electrospun PVA nanofibers thickness, freeze-thaw cycles, and the DS saturation has improved the physicochemical and mechanical properties of the DS medicated dual layer PVA patches, making them a promising biomaterial for transdermal drug delivery applications.

Structure and biological compatibility of polycaprolactone/zinc-hydroxyapatite electrospun nanofibers for tissue regeneration

Although guided tissue regeneration (GTR) is a useful tool for regenerating lost tissue as bone and periodontal tissue, a biocompatible membrane capable of regenerating large defects has yet to be discovered. This study aimed to characterize the physicochemical properties and biological compatibility of polycaprolactone (PCL) membranes associated with or without nanostructured hydroxyapatite (HA) (PCL/HA) and Zn-doped HA (PCL/ZnHA), produced by electrospinning. PCL, PCL/HA, and PCL/ZnHA were characterized by field emission scanning electron microscopy (FESEM), transmission electron microscopy (TEM), energy dispersive X-ray spectroscopy (EDS), X-ray diffraction (XRD), thermal gravimetric analysis (TGA), and differential scanning calorimetry (DSC). Nanoparticles of HA or ZnHA were homogeneously distributed and dispersed inside the PCL fibers, which decreased the fiber thickness. At 1 wt% of HA or ZnHA, these nanoparticles acted as nucleating agents. Moreover, HA and ZnHA increased the onset of the degradation temperature and thermal stability of the electrospun membrane. All tested membranes showed no cytotoxicity and allowed murine pre-osteoblast adhesion and spreading; however, higher concentrations of PCL/ZnHA showed less cells and an irregular cell morphology compared to PCL and PCL/HA. This article presents a cytocompatible, electrospun, nanocomposite membrane with a novel morphology and physicochemical properties that make it eligible as a scaffold for GTR.