Electrospun cellulose acetate/gelatin nanofibrous wound dressing containing berberine for diabetic foot ulcer healing: in vitro and in vivo studies

Fumaria officinalis-loaded chitosan nanoparticles dispersed in an alginate hydrogel promote diabetic wounds healing by upregulating VEGF, TGF-β, and b-FGF genes: A preclinical investigation

Diabetic wounds may become chronic if left untreated. In the current study, a potential wound dressing was developed by incorporating fumaria officinalis extract-loaded chitosan nanoparticles (FOE-CHNPs) into calcium alginate hydrogel. The produced hydrogel was evaluated regarding its microarchitecture, cytotoxicity, cell migration activity, cytoprotective potential, porosity, in vitro anti-inflammatory activity, and drug release profile. Then, the healing function of FOE-CHNPs/calcium alginate hydrogel was compared with a marketed wound care product in a rat model of diabetic wound. In vitro study showed that the hydrogel system promoted skin cells viability and migration. In vivo wound healing assay showed that the animals treated with the FOE-CHNPs/calcium alginate hydrogel had comparable wound healing potential with the GranuGEL® as the marketed wound care hydrogel. Gene expression studies showed that FOE-CHNPs/calcium alginate hydrogel upregulated the tissue expression levels of collagen type 1, collagen type 2, VEGF, b-FGF and TGF-B genes. This preclinical research, suggests potential use of FOE-loaded calcium alginate hydrogel system in treating diabetic wounds in the clinic.

Perspectives of nanofibrous wound dressings based on glucans and galactans - A review

Wound healing is a complex and dynamic process that needs an appropriate environment to overcome infection and inflammation to progress well. Wounds lead to morbidity, mortality, and a significant economic burden, often due to the non-availability of suitable treatments. Hence, this field has lured the attention of researchers and pharmaceutical industries for decades. As a result, the global wound care market is expected to be 27.8 billion USD by 2026 from 19.3 billion USD in 2021, at a compound annual growth rate (CAGR) of 7.6 %. Wound dressings have emerged as an effective treatment to maintain moisture, protect from pathogens, and impede wound healing. However, synthetic polymer-based dressings fail to comprehensively address optimal and quick regeneration requirements. Natural polymers like glucan and galactan-based carbohydrate dressings have received much attention due to their inherent biocompatibility, biodegradability, inexpensiveness, and natural abundance. Also, nanofibrous mesh supports better proliferation and migration of fibroblasts because of their large surface area and similarity to the extracellular matrix (ECM). Thus, nanostructured dressings derived from glucans and galactans (i.e., chitosan, agar/agarose, pullulan, curdlan, carrageenan, etc.) can overcome the limitations associated with traditional wound dressings. However, they require further development pertaining to the wireless determination of wound bed status and its clinical assessment. The present review intends to provide insight into such carbohydrate-based nanofibrous dressings and their prospects, along with some clinical case studies.

Electrospun nanofibers for medical face mask with protection capabilities against viruses: State of the art and perspective for industrial scale-up

Face masks have proven to be a useful protection from airborne viruses and bacteria, especially in the recent years pandemic outbreak when they effectively lowered the risk of infection from Coronavirus disease (COVID-19) or Omicron variants, being recognized as one of the main protective measures adopted by the World Health Organization (WHO). The need for improving the filtering efficiency performance to prevent penetration of fine particulate matter (PM), which can be potential bacteria or virus carriers, has led the research into developing new methods and techniques for face mask fabrication. In this perspective, Electrospinning has shown to be the most efficient technique to get either synthetic or natural polymers-based fibers with size down to the nanoscale providing remarkable performance in terms of both particle filtration and breathability. The aim of this Review is to give further insight into the implementation of electrospun nanofibers for the realization of the next generation of face masks, with functionalized membranes via addiction of active material to the polymer solutions that can give optimal features about antibacterial, antiviral, self-sterilization, and electrical energy storage capabilities. Furthermore, the recent advances regarding the use of renewable materials and green solvent strategies to improve the sustainability of electrospun membranes and to fabricate eco-friendly filters are here discussed, especially in view of the large-scale nanofiber production where traditional membrane manufacturing may result in a high environmental and health risk.

Gelatin nanofibers: Recent insights in synthesis, bio-medical applications and limitations

The use of gelatin and gelatin-blend polymers as environmentally safe polymers to synthesis electrospun nanofibers, has caused a revolution in the biomedical field. The development of efficient nanofibers has played a significant role in drug delivery, and for use in advanced scaffolds in regenerative medicine. Gelatin is an exceptional biopolymer, which is highly versatile, despite variations in the processing technology. The electrospinning process is an efficient technique for the manufacture of gelatin electrospun nanofibers (GNFs), as it is simple, efficient, and cost-effective. GNFs have higher porosity with large surface area and biocompatibility, despite that there are some drawbacks. These drawbacks include rapid degradation, poor mechanical strength, and complete dissolution, which limits the use of gelatin electrospun nanofibers in this form for biomedicine. Thus, these fibers need to be cross-linked, in order to control its solubility. This modification caused an improvement in the biological properties of GNFs, which made them suitable candidates for various biomedical applications, such as wound healing, drug delivery, bone regeneration, tubular scaffolding, skin, nerve, kidney, and cardiac tissue engineering. In this review an outline of electrospinning is shown with critical summary of literature evaluated with respect to the various applications of nanofibers-derived gelatin.

Measuring Physical Properties of Electrospun Nanofiber Mats for Different Biomedical Applications

Electrospun nanofiber mats are nowadays often used for biotechnological and biomedical applications, such as wound healing or tissue engineering. While most studies concentrate on their chemical and biochemical properties, the physical properties are often measured without long explanations regarding the chosen methods. Here, we give an overview of typical measurements of topological features such as porosity, pore size, fiber diameter and orientation, hydrophobic/hydrophilic properties and water uptake, mechanical and electrical properties as well as water vapor and air permeability. Besides describing typically used methods with potential modifications, we suggest some low-cost methods as alternatives in cases where special equipment is not available.

Design and characterization of adipose-derived mesenchymal stem cell loaded alginate/pullulan/hyaluronic acid hydrogel scaffold for wound healing applications

Recently, significant attention has been focused on the progression of skin equivalents to facilitate faster wound healing and thereby skin restoration. The main aim of this study was the design and characterization of a novel polysaccharide-based hydrogel scaffold by using alginate, pullulan, and hyaluronic acid polymers to provide an appropriate microenvironment to deliver Adipose-derived mesenchymal Stem Cells (ASC) in order to promote wound healing in an animal model. Characterization of synthesized hydrogel was done by using a field emission scanning electron microscope (FE-SEM), Fourier Transform-Infrared spectroscopy (FT-IR), and Differential Scanning Calorimetry (DSC). Also, contact angle analysis, the swelling and mechanical tests were performed. As a result of in vitro studies, cells can be attached, alive, and migrate through the prepared hydrogel scaffold. Finally, the therapeutic effect of the cell-seeded hydrogels was tested in the full-thickness animal wound model. Based on obtained results, the hydrogel-ASC treatment improved the healing process and accelerated wound closure.

A review on polysaccharides mediated electrospun nanofibers for diabetic wound healing: Their current status with regulatory perspective

The current treatment strategies for diabetic wound care provide only moderate degree of effectiveness; hence new and improved therapeutic techniques are in great demand. Diabetic wound healing is a complex physiological process that involves synchronisation of various biological events such as haemostasis, inflammation, and remodelling. Nanomaterials like polymeric nanofibers (NFs) offer a promising approach for the treatment of diabetic wounds and have emerged as viable options for wound management. Electrospinning is a powerful and cost-effective method to fabricate versatile NFs with a wide array of raw materials for different biological applications. The electrospun NFs have unique advantages in the development of wound dressings due to their high specific surface area and porosity. The electrospun NFs possess a unique porous structure and biological function similar to the natural extracellular matrix (ECM), and are known to accelerate wound healing. Compared to traditional dressings, the electrospun NFs are more effective in healing wounds owing to their distinct characteristics, good surface functionalisation, better biocompatibility and biodegradability. This review provides a comprehensive overview of the electrospinning procedure and its operating principle, with special emphasis on the role of electrospun NFs in the treatment of diabetic wounds. This review discusses the present techniques applied in the fabrication of NF dressings, and highlights the future prospects of electrospun NFs in medicinal applications.

Microwave-Assisted Incorporation of AgNP into Chitosan-Alginate Hydrogels for Antimicrobial Applications

Herein, improving the antibacterial activity of a hydrogel system of sodium alginate (SA) and basic chitosan (CS) using sodium hydrogen carbonate by adding AgNPs was investigated. SA-coated AgNPs produced by ascorbic acid or microwave heating were evaluated for their antimicrobial activity. Unlike ascorbic acid, the microwave-assisted method produced uniform and stable SA-AgNPs with an optimal reaction time of 8 min. Transmission electron microscopy (TEM) confirmed the formation of SA-AgNPs with an average particle size of 9 ± 2 nm. Moreover, UV-vis spectroscopy confirmed the optimal conditions for SA-AgNP synthesis (0.5% SA, 50 mM AgNO₃, and pH 9 at 80 °C). Fourier transform infrared (FTIR) spectroscopy confirmed that the -COO^- group of SA electrostatically interacted with either the Ag⁺ or -NH₃⁺ of CS. Adding glucono-δ-lactone (GDL) to the mixture of SA-AgNPs/CS resulted in a low pH (below the pKa of CS). An SA-AgNPs/CS gel was formed successfully and retained its shape. This hydrogel exhibited 25 ± 2 mm and 21 ± 1 mm inhibition zones against E. coli and B. subtilis and showed low cytotoxicity. Additionally, the SA-AgNP/CS gel showed higher mechanical strength than SA/CS gels, possibly due to the higher crosslink density. In this work, a novel antibacterial hydrogel system was synthesized via 8 min of microwave heating.

Electrospinning Nanofibers as a Dressing to Treat Diabetic Wounds

Globally, diabetic mellitus (DM) is a common metabolic disease that effectively inhibits insulin production, destroys pancreatic β cells, and consequently, promotes hyperglycemia. This disease causes complications, including slowed wound healing, risk of infection in wound areas, and development of chronic wounds all of which are significant sources of mortality. With an increasing number of people diagnosed with DM, the current method of wound healing does not meet the needs of patients with diabetes. The lack of antibacterial ability and the inability to sustainably deliver necessary factors to wound areas limit its use. To overcome this, a new method of creating wound dressings for diabetic patients was developed using an electrospinning methodology. The nanofiber membrane mimics the extracellular matrix with its unique structure and functionality, owing to which it can store and deliver active substances that greatly aid in diabetic wound healing. In this review, we discuss several polymers used to create nanofiber membranes and their effectiveness in the treatment of diabetic wounds.

Exopolysaccharide from the yeast Papiliotrema terrestris PT22AV for skin wound healing

INTRODUCTION

Exopolysaccharides (EPSs) are high-value functional biomaterials mainly produced by bacteria and fungi, with nutraceutical, therapeutic and industrial potentials.

OBJECTIVES

This study sought to characterize and assess the biological properties of the EPS produced by the yeast Papiliotrema terrestris PT22AV.

METHODS

After extracting the yeast's DNA and its molecular identification, the EPS from P. terrestris PT22AV strain was extracted and its physicochemical properties (structural, morphological, monosaccharide composition and molecular weight) were characterized. The EPS's in vitro biological activities and in vivo wound healing potential were also evaluated.

RESULTS

The obtained EPS was water-soluble and revealed an average molecular weight (Mw) of 202 kDa. Mannose and glucose with 97% and 3% molar percentages, respectively, constituted the EPS. In vitro antibacterial activity analysis of the extracted EPS exhibited antibacterial activity (>80%) against Escherichia coli, Staphylococcus aureus, and Staphylococcus epidermidis at a concentration of 2 mg/mL. The EPS showed cytocompatibility against the human fibroblast and macrophage cell lines and the animal studies showed a dose-dependent wound healing capacity of the EPS with higher wound closure at 10 mg/mL compared to negative and positive control after 14 days.

CONCLUSION

The EPS from P. terrestris PT22AV could serve as a promising source of biocompatible macromolecules with potential for skin wound healing.

Plasma-Polymerised Antibacterial Coating of Ovine Tendon Collagen Type I (OTC) Crosslinked with Genipin (GNP) and Dehydrothermal-Crosslinked (DHT) as a Cutaneous Substitute for Wound Healing

Tissue engineering products have grown in popularity as a therapeutic approach for chronic wounds and burns. However, some drawbacks include additional steps and a lack of antibacterial capacities, both of which need to be addressed to treat wounds effectively. This study aimed to develop an acellular, ready-to-use ovine tendon collagen type I (OTC-I) bioscaffold with an antibacterial coating for the immediate treatment of skin wounds and to prevent infection post-implantation. Two types of crosslinkers, 0.1% genipin (GNP) and dehydrothermal treatment (DHT), were explored to optimise the material strength and biodegradability compared with a non-crosslinked (OTC) control. Carvone plasma polymerisation (ppCar) was conducted to deposit an antibacterial protective coating. Various parameters were performed to investigate the physicochemical properties, mechanical properties, microstructures, biodegradability, thermal stability, surface wettability, antibacterial activity and biocompatibility of the scaffolds on human skin cells between the different crosslinkers, with and without plasma polymerisation. GNP is a better crosslinker than DHT because it demonstrated better physicochemical properties (27.33 ± 5.69% vs. 43 ± 7.64% shrinkage), mechanical properties (0.15 ± 0.15 MPa vs. 0.07 ± 0.08 MPa), swelling (2453 ± 419.2% vs. 1535 ± 392.9%), biodegradation (0.06 ± 0.06 mg/h vs. 0.15 ± 0.16 mg/h), microstructure and biocompatibility. Similarly, its ppCar counterpart, GNPppCar, presents promising results as a biomaterial with enhanced antibacterial properties. Plasma-polymerised carvone on a crosslinked collagen scaffold could also support human skin cell proliferation and viability while preventing infection. Thus, GNPppCar has potential for the rapid treatment of healing wounds.

Antioxidant Biomaterials in Cutaneous Wound Healing and Tissue Regeneration: A Critical Review

Natural-based biomaterials play an important role in developing new products for medical applications, primarily in cutaneous injuries. A large panel of biomaterials with antioxidant properties has revealed an advancement in supporting and expediting tissue regeneration. However, their low bioavailability in preventing cellular oxidative stress through the delivery system limits their therapeutic activity at the injury site. The integration of antioxidant compounds in the implanted biomaterial should be able to maintain their antioxidant activity while facilitating skin tissue recovery. This review summarises the recent literature that reported the role of natural antioxidant-incorporated biomaterials in promoting skin wound healing and tissue regeneration, which is supported by evidence from in vitro, in vivo, and clinical studies. Antioxidant-based therapies for wound healing have shown promising evidence in numerous animal studies, even though clinical studies remain very limited. We also described the underlying mechanism of reactive oxygen species (ROS) generation and provided a comprehensive review of ROS-scavenging biomaterials found in the literature in the last six years.

Nanofibrous Scaffolds for Diabetic Wound Healing

Chronic wounds are one of the secondary health complications that develop in individuals who have poorly managed diabetes mellitus. This is often associated with delays in the wound healing process, resulting from long-term uncontrolled blood glucose levels. As such, an appropriate therapeutic approach would be maintaining blood glucose concentration within normal ranges, but this can be quite challenging to achieve. Consequently, diabetic ulcers usually require special medical care to prevent complications such as sepsis, amputation, and deformities, which often develop in these patients. Although several conventional wound dressings, such as hydrogels, gauze, films, and foams, are employed in the treatment of such chronic wounds, nanofibrous scaffolds have gained the attention of researchers because of their flexibility, ability to load a variety of bioactive compounds as single entities or combinations, and large surface area to volume ratio, which provides a biomimetic environment for cell proliferation relative to conventional dressings. Here, we present the current trends on the versatility of nanofibrous scaffolds as novel platforms for the incorporation of bioactive agents suitable for the enhancement of diabetic wound healing.

Smart Bandaid Integrated with Fully Textile OECT for Uric Acid Real-Time Monitoring in Wound Exudate

Hard-to-heal wounds (i.e., severe and/or chronic) are typically associated with particular pathologies or afflictions such as diabetes, immunodeficiencies, compression traumas in bedridden people, skin grafts, or third-degree burns. In this situation, it is critical to constantly monitor the healing stages and the overall wound conditions to allow for better-targeted therapies and faster patient recovery. At the moment, this operation is performed by removing the bandages and visually inspecting the wound, putting the patient at risk of infection and disturbing the healing stages. Recently, new devices have been developed to address these issues by monitoring important biomarkers related to the wound health status, such as pH, moisture, etc. In this contribution, we present a novel textile chemical sensor exploiting an organic electrochemical transistor (OECT) configuration based on poly(3,4-ethylenedioxythiophene):polystyrene sulfonate (PEDOT:PSS) for uric acid (UA)-selective monitoring in wound exudate. The combination of special medical-grade textile materials provides a passive sampling system that enables the real-time and non-invasive analysis of wound fluid: UA was detected as a benchmark analyte to monitor the health status of wounds since it represents a relevant biomarker associated with infections or necrotization processes in human tissues. The sensors proved to reliably and reversibly detect UA concentration in synthetic wound exudate in the biologically relevant range of 220-750 μM, operating in flow conditions for better mimicking the real wound bed. This forerunner device paves the way for smart bandages integrated with real-time monitoring OECT-based sensors for wound-healing evaluation.

Phytotherapy in Diabetic Foot Ulcers: A Promising Strategy for Effective Wound Healing

Despite the advancement in wound care, the effective therapy of chronic diabetic ulcers continues to be a challenge. Wound healing is a highly controlled process, which involves a sequence of complex overlapping steps. This healing pathway comprises of hemostasis, inflammation, proliferative, and remodeling phases. Recent evidence suggests that phytomedicines can prevent or repair different kinds of destructive cellular damage, including chronic wounds. Several phytochemicals such as polyphenols, alkaloids, flavonoids, terpenoids, and glycosides have pleiotropic effects, including stimulation of fibroblast proliferation, the main step in wound healing. Besides, the mechanism involves induction of collagen synthesis, migration, and reepithelization and their antimicrobial, antioxidant, anti-inflammatory, and immunomodulatory actions. Similarly, the use of phytochemicals alone or as an adjuvant with standard therapy has demonstrated promising results in managing complications in the diabetic foot. For instance, the extract of Carica papaya has been shown antioxidant, antimicrobial, and anti-inflammatory, and immunomodulatory effects, which, together with proteolytic enzymatic activity, contributes to its wound healing property. It is generally believed that phytotherapy has no or minimal toxicity than synthetic therapeutic agents, favoring its use in diabetic foot ulcer management. The current review highlights the selected phytochemicals and their sources; and potential application in diabetic foot ulcer management.Key teaching points and nutritional relevanceCurrently, phytochemicals have been shown wide potential in disease. management including alleviating clinical manifestations, preventing degenerative disease, and curing illness.Increased evidence of phytochemical as anti-infective and anti-inflammatory suggests its role in the management of diabetic foot ulcer(DFU).Potential benefit along with minimal adverse effect favors its application as adjuvant therapy.Further research is needed to standardize its dose and formulation to enhance its clinical application in DFU management.

Therapeutic Efficacy of Polymeric Biomaterials in Treating Diabetic Wounds-An Upcoming Wound Healing Technology

Diabetic wounds are one of the serious, non-healing, chronic health issues faced by individuals suffering from diabetic mellitus. The distinct phases of wound healing are either prolonged or obstructed, resulting in the improper healing of diabetic wounds. These injuries require persistent wound care and appropriate treatment to prevent deleterious effects such as lower limb amputation. Although there are several treatment strategies, diabetic wounds continue to be a major threat for healthcare professionals and patients. The different types of diabetic wound dressings that are currently used differ in their properties of absorbing wound exudates and may also cause maceration to surrounding tissues. Current research is focused on developing novel wound dressings incorporated with biological agents that aid in a faster rate of wound closure. An ideal wound dressing material must absorb wound exudates, aid in the appropriate exchange of gas, and protect from microbial infections. It must support the synthesis of biochemical mediators such as cytokines, and growth factors that are crucial for faster healing of wounds. This review highlights the recent advances in polymeric biomaterial-based wound dressings, novel therapeutic regimes, and their efficacy in treating diabetic wounds. The role of polymeric wound dressings loaded with bioactive compounds, and their in vitro and in vivo performance in diabetic wound treatment are also reviewed.

Electrospun Nanomaterials Based on Cellulose and Its Derivatives for Cell Cultures: Recent Developments and Challenges

The development of electrospun nanofibers based on cellulose and its derivatives is an inalienable task of modern materials science branches related to biomedical engineering. The considerable compatibility with multiple cell lines and capability to form unaligned nanofibrous frameworks help reproduce the properties of natural extracellular matrix and ensure scaffold applications as cell carriers promoting substantial cell adhesion, growth, and proliferation. In this paper, we are focusing on the structural features of cellulose itself and electrospun cellulosic fibers, including fiber diameter, spacing, and alignment responsible for facilitated cell capture. The study emphasizes the role of the most frequently discussed cellulose derivatives (cellulose acetate, carboxymethylcellulose, hydroxypropyl cellulose, etc.) and composites in scaffolding and cell culturing. The key issues of the electrospinning technique in scaffold design and insufficient micromechanics assessment are discussed. Based on recent studies aiming at the fabrication of artificial 2D and 3D nanofiber matrices, the current research provides the applicability assessment of the scaffolds toward osteoblasts (hFOB line), fibroblastic (NIH/3T3, HDF, HFF-1, L929 lines), endothelial (HUVEC line), and several other cell types. Furthermore, a critical aspect of cell adhesion through the adsorption of proteins on the surfaces is touched upon.

Local Drug Delivery Strategies towards Wound Healing

A particular biological process known as wound healing is connected to the overall phenomena of growth and tissue regeneration. Several cellular and matrix elements work together to restore the integrity of injured tissue. The goal of the present review paper focused on the physiology of wound healing, medications used to treat wound healing, and local drug delivery systems for possible skin wound therapy. The capacity of the skin to heal a wound is the result of a highly intricate process that involves several different processes, such as vascular response, blood coagulation, fibrin network creation, re-epithelialisation, collagen maturation, and connective tissue remodelling. Wound healing may be controlled with topical antiseptics, topical antibiotics, herbal remedies, and cellular initiators. In order to effectively eradicate infections and shorten the healing process, contemporary antimicrobial treatments that include antibiotics or antiseptics must be investigated. A variety of delivery systems were described, including innovative delivery systems, hydrogels, microspheres, gold and silver nanoparticles, vesicles, emulsifying systems, nanofibres, artificial dressings, three-dimensional printed skin replacements, dendrimers and carbon nanotubes. It may be inferred that enhanced local delivery methods might be used to provide wound healing agents for faster healing of skin wounds.

Berberine promotes the viability of random skin flaps via the PI3K/Akt/eNOS signaling pathway

Random skin flaps are often used in reconstruction operations. However, flap necrosis is still a common postoperative complication. Here, we investigated whether berberine (C₂₀ H₁₉ NO₅ , BBR), a drug with antioxidant activity, improves the survival rate of random flaps. Fifty-four rats were divided into three groups: control, BBR and BBR + _L -NAME groups (_L -NAME, _L -N^G -Nitro-arginine methyl ester). The survival condition and the percentage of survival area of the flaps were evaluated on the seventh day after surgery. After animals were sacrificed, angiogenesis, apoptosis, oxidative stress and inflammation levels were assessed by histological and protein analyses. Our findings suggest that berberine promotes flap survival. The level of angiogenesis increased; the levels of oxidative stress, inflammation and apoptosis decreased; the levels of phosphoinositide 3-kinase (PI3K), phospho-Akt (p-Akt) and phospho-endothelial nitric oxide synthase (p-eNOS) increased in the flap tissue; and _L -NAME reversed the effects of berberine on random skin flaps. Statistical analysis showed that the BBR group results differed significantly from those of the control and the BBR + _L -NAME groups (p < .05). Our results confirm that berberine is an effective drug for significantly improving the survival rate of random skin flaps by promoting angiogenesis, inhibiting inflammation, attenuating oxidative stress, and reducing apoptosis through the PI3K/Akt/eNOS signaling pathway.

Nicaraven-loaded electrospun wound dressings promote diabetic wound healing via proangiogenic and immunomodulatory functions: a preclinical investigation

The current study developed a biopolymer-based wound dressing by electrospinning of Nicaraven-loaded collagen solution. Firstly, collagen was dissolved in acetic acid, and then Nicaraven was added to the polymeric solution at three different concentrations of 2 w/w%, 4 w/w%, and 6 w/w%. The resulting solution was then electrospun. Various experiments were performed to characterize the produced wound dressings. In vitro studies showed that Nicaraven-loaded scaffolds were not toxic against L929 fibroblast cells and protected them against oxidative stress. Wound healing potential of different formulations of Nicaraven-loaded collagen wound dressings was studied in a rat model of the excisional diabetic wound. The study showed that the collagen/4% Nicaraven and collagen/6% Nicaraven wound dressings exhibited a significantly higher percentage of wound closure, the thickness of the epithelium, and collagen deposition compared with collagen/2% Nicaraven, collagen-only, and sterile gauze groups. Gene expression study showed that the developed wound dressings reduced the tissue expression levels of glutathione peroxidase, NFKβ, and matrix metalloproteinase 9 (MMP9) genes. In addition, in the wounds treated with collagen/4% Nicaraven and collagen/6% Nicaraven scaffolds, wound healing was associated with a higher tissue expression level of b-FGF, VEGF, and collagen type I genes. Overall, wound healing activity of collagen/4% Nicaraven and collagen/6% Nicaraven wound dressings was not significantly different. This study implies that collagen wound dressings incorporated with 4% and 6% Nicaraven can be considered a potential candidate to treat diabetic wounds in the clinic.

Fig latex inhibits the growth of pathogenic bacteria invading human diabetic wounds and accelerates wound closure in diabetic mice

Impaired wound healing is one of the most critical complications associated with diabetes mellitus. Infections and foot ulcers are major causes of morbidity for diabetic patients. The current treatment of diabetic foot ulcers, commonly used antibiotics, is associated with the development of bacterial resistance. Hence, novel and more effective natural therapeutic antibacterial agents are urgently needed and should be developed against the pathogenic bacteria inhabiting diabetic wounds. Therefore, the current study aimed to investigate the impact of fig latex on pathogenic bacteria and its ability to promote the healing process of diabetic wounds. The pathogenic bacteria were isolated from patients with diabetic foot ulcers admitted to Assiut University Hospital. Fig latex was collected from trees in the Assiut region, and its chemical composition was analyzed using GC‒MS. The antibacterial efficacy of fig latex was assessed on the isolated bacteria. An in vivo study to investigate the effect of fig latex on diabetic wound healing was performed using three mouse groups: nondiabetic control mice, diabetic mice and diabetic mice treated with fig latex. The influence of fig latex on the expression levels of β-defensin-1, PECAM-1, CCL2 and ZO-1 and collagen formation was investigated. The GC‒MS analysis demonstrated the presence of triterpenoids, comprising more than 90% of the total latex content. Furthermore, using a streptozotocin-induced diabetic mouse model, topical treatment of diabetic wound tissues with fig latex was shown to accelerate and improve wound closure by increasing the expression levels of β-defensin-1, collagen, and PECAM-1 compared to untreated diabetic wounds. Additionally, fig latex decreased the expression levels of ZO-1 and CCL2.

Idebenone-loaded wound dressings promote diabetic wound healing through downregulation of Il1b, Nfkb genes and upregulation of Fgf2 gene

Reactive oxygen species (ROS) are overproduced in diabetic wounds and retard the healing response. Considering the antioxidative function of idebenone, its exogenous administration may quench excessive ROS and promote diabetic wound healing. In the current study, idebenone was loaded into polyvinyl alcohol (PVA) /calcium alginate scaffolds at three different concentrations of 1 w/w%, 2 w/w%, and 3 w/w%. Various in vitro experiments were performed to characterize the developed wound dressings. Cell viability assay showed that scaffolds loaded with 1 w/w% idebenone had significantly better protection under oxidative stress and exhibited higher cell viability. Therefore, the dressings containing 1% drug was chosen to treat diabetic wounds in rat model. Wound healing assay showed that the dressings loaded with 1% drug had significantly higher rate of wound size reduction, collagen deposition, and epithelial thickness. Gene expression study showed that wound healing was accompanied by modulation of inflammatory response, protection against oxidative stress, and increasing angiogenesis-related genes. This preliminary research suggests that PVA/calcium alginate/1% idebenone scaffolds can be considered as a potential treatment modality to treat diabetic wounds in the clinic. However, more extensive studies at gene and protein expression levels are required to understand its exact mechanism of healing effects.

Fabrication and characterization of electrospun GelMA/PCL/CS nanofiber composites for wound dressing applications

In the present study, the effect of different ratios of GelMA concentration has been exhibited for wound dressing implementation by the electrospinning method using a new polymer combination of Gelatin methacrylate (GelMA)/Polycaprolactone (PCL)/Chitosan (CS). The nanofiber composites were fabricated due to their biocompatible, biodegradable, improved mechanical strength, low degradation rate, and hydrophilic nature to develop cell-mimicking, cell adhesion, proliferation, and differentiation. Different concentrations of GelMA were added to the PCL/CS solution as 5, 10, and 20 wt%, respectively, in the formic acid/acetic acid (7:3) solution. A photoinitiator was added to the solution for photo-crosslinking of GelMA. The influence of different solution concentrations (5, 10, and 20 wt%) on the structure’s nanofiber production and fiber morphology was examined. SEM micrographs revealed that varied GelMA concentrations resulted in suitable and stable nanofiber composites. The average diameter of nanofiber composites grows as the GelMA concentration rises. FTIR, DSC, tensile test, degradation, and swelling test were evaluated. The results demonstrated that high mechanical strength, hydrophilic properties, and a slow degradation rate were observed with the presence and increment of GelMA concentration within the nanofiber composites. The antibacterial potential of GelMA/PCL/CS nanofiber composites was evaluated against P. aeruginosa and S. aureus using a disc diffusion assay. In vitro cell culture research was conducted by seeding NIH 3T3 fibroblast cells on nanofiber composites, proving these cells’ high cell proliferation rate, viability, and adhesion. 10 wt% GelMA-based nanofiber composites were found to have great potential for wound dressing applications.

Alginate-Based Hydrogels Composited with Tenocyclidine-Loaded Chitosan Nanoparticles, a Sophisticated Delivery System for Transplantation of Allogenic Schwan Cells Through Cellulose Acetate Neural Guidance Channels: A Preclinical Study

In the current study, a novel filler material was developed to improve the healing activity of an electrospun cellulose acetate neural guidance channel. Tenocyclidine was loaded into chitosan nanoparticles, dispersed in a calcium alginate hydrogel, and their effect on Schwann cells’ viability was assessed using MTT assay. Study showed that chitosan nanoparticles loaded with 0.5% Tenocyclidine had the optimal effects on cells viability. In vivo study on a rat model of peripheral nerve injury showed that the neural guidance channels containing Schwann cells and Tenocyclidine-loaded chitosan nanoparticles had the highest rate of nerve repair as evidenced by functional analysis assays and histopathological examinations.

Electrospun hybrid nanofibers: Fabrication, characterization, and biomedical applications

Nanotechnology is one of the most promising technologies available today, holding tremendous potential for biomedical and healthcare applications. In this field, there is an increasing interest in the use of polymeric micro/nanofibers for the construction of biomedical structures. Due to its potential applications in various fields like pharmaceutics and biomedicine, the electrospinning process has gained considerable attention for producing nano-sized fibers. Electrospun nanofiber membranes have been used in drug delivery, controlled drug release, regenerative medicine, tissue engineering, biosensing, stent coating, implants, cosmetics, facial masks, and theranostics. Various natural and synthetic polymers have been successfully electrospun into ultrafine fibers. Although biopolymers demonstrate exciting properties such as good biocompatibility, non-toxicity, and biodegradability, they possess poor mechanical properties. Hybrid nanofibers from bio and synthetic nanofibers combine the characteristics of biopolymers with those of synthetic polymers, such as high mechanical strength and stability. In addition, a variety of functional agents, such as nanoparticles and biomolecules, can be incorporated into nanofibers to create multifunctional hybrid nanofibers. Due to the remarkable properties of hybrid nanofibers, the latest research on the unique properties of hybrid nanofibers is highlighted in this study. Moreover, various established hybrid nanofiber fabrication techniques, especially the electrospinning-based methods, as well as emerging strategies for the characterization of hybrid nanofibers, are summarized. Finally, the development and application of electrospun hybrid nanofibers in biomedical applications are discussed.

Gallic Acid-Loaded Sodium Alginate-Based (Polyvinyl Alcohol-Co-Acrylic Acid) Hydrogel Membranes for Cutaneous Wound Healing: Synthesis and Characterization

Traditional wound dressings often cannot treat wounds caused by bacterial infections or other wound types that are insensitive to these wound treatments. Therefore, a biodegradable, bioactive hydrogel wound dressing could be an effective alternative option. The purpose of this study was to develop a hydrogel membrane comprised of sodium alginate, polyvinyl alcohol, acrylic acid, and gallic acid for treating skin wounds. The newly developed membranes were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), sol-gel fraction, porosity, mechanical strength, swelling, drug release and data modelling, polymeric network parameters, biodegradation, and antioxidation (DPPH and ABTS) and antimicrobial activity against Gram-positive and negative bacteria. The results revealed that hydrogel membranes were crosslinked successfully and had excellent thermal stability, high drug loading, greater mechanical strength, and exhibited excellent biodegradation. Additionally, the swelling ability and the porosity of the surface facilitated a controlled release of the encapsulated drug (gallic acid), with 70.34% release observed at pH 1.2, 70.10% at pH 5.5 (normal skin pH), and 86.24% at pH 7.4 (wounds pH) in 48 h. The gallic acid-loaded hydrogel membranes showed a greater area of inhibition against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli bacteria as well as demonstrated excellent antioxidant properties. Based on Franz cell analyses, the permeation flux of the drug from optimized formulations through mice skin was 92 (pH 5.5) and 110 (pH 7.4) μg/cm²·h^-1. Moreover, hydrogel membranes retained significant amounts of drug in the skin for 24 h, such as 2371 (pH 5.5) and 3300 µg/cm² (pH 7.4). Acute dermal irritation tests in rats showed that hydrogel membranes were nonirritating. Hydrogel membranes containing gallic acid could be an effective option for improving wound healing and could result in faster wound healing.

Effect of composite biodegradable biomaterials on wound healing in diabetes

The repair of diabetic wounds has always been a job that doctors could not tackle quickly in plastic surgery. To solve this problem, it has become an important direction to use biocompatible biodegradable biomaterials as scaffolds or dressing loaded with a variety of active substances or cells, to construct a wound repair system integrating materials, cells, and growth factors. In terms of wound healing, composite biodegradable biomaterials show strong biocompatibility and the ability to promote wound healing. This review describes the multifaceted integration of biomaterials with drugs, stem cells, and active agents. In wounds, stem cells and their secreted exosomes regulate immune responses and inflammation. They promote angiogenesis, accelerate skin cell proliferation and re-epithelialization, and regulate collagen remodeling that inhibits scar hyperplasia. In the process of continuous combination with new materials, a series of materials that can be well matched with active ingredients such as cells or drugs are derived for precise delivery and controlled release of drugs. The ultimate goal of material development is clinical transformation. At present, the types of materials for clinical application are still relatively single, and the bottleneck is that the functions of emerging materials have not yet reached a stable and effective degree. The development of biomaterials that can be further translated into clinical practice will become the focus of research.

Advances in the Preparation of Nanofiber Dressings by Electrospinning for Promoting Diabetic Wound Healing

Chronic diabetic wounds are one of the main complications of diabetes, manifested by persistent inflammation, decreased epithelialization motility, and impaired wound healing. This will not only lead to the repeated hospitalization of patients, but also bear expensive hospitalization costs. In severe cases, it can lead to amputation, sepsis or death. Electrospun nanofibers membranes have the characteristics of high porosity, high specific surface area, and easy functionalization of structure, so they can be used as a safe and effective platform in the treatment of diabetic wounds and have great application potential. This article briefly reviewed the pathogenesis of chronic diabetic wounds and the types of dressings commonly used, and then reviewed the development of electrospinning technology in recent years and the advantages of electrospun nanofibers in the treatment of diabetic wounds. Finally, the reports of different types of nanofiber dressings on diabetic wounds are summarized, and the method of using multi-drug combination therapy in diabetic wounds is emphasized, which provides new ideas for the effective treatment of diabetic wounds.

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.

Dual-Functional Nanofibrous Patches for Accelerating Wound Healing

Bacterial infections and inflammation are two main factors for delayed wound healing. Coaxial electrospinning nanofibrous patches, by co-loading and sequential co-delivering of anti-bacterial and anti-inflammation agents, are promising wound dressing for accelerating wound healing. Herein, curcumin (Cur) was loaded into the polycaprolactone (PCL) core, and broad-spectrum antibacterial tetracycline hydrochloride (TH) was loaded into gelatin (GEL) shell to prepare PCL-Cur/GEL-TH core-shell nanofiber membranes. The fibers showed a clear co-axial structure and good water absorption capacity, hydrophilicity and mechanical properties. In vitro drug release results showed sequential release of Cur and TH, in which the coaxial mat showed good antioxidant activity by DPPH test and excellent antibacterial activity was demonstrated by a disk diffusion method. The coaxial mats showed superior biocompatibility toward human immortalized keratinocytes. This study indicates a coaxial nanofiber membrane combining anti-bacterial and anti-inflammation agents has great potential as a wound dressing for promoting wound repair.

Evaluation of the healing properties of Garcinia brasiliensis extracts in a cutaneous wound model

ETHNOPHARMACOLOGICAL RELEVANCE

Wound healing is a complex process that can leave pathological scars, especially in case of infections from opportunistic microorganisms. In this context, herbal medicines open up great possibilities for investigation. One of the species of interest native to Brazil is Garcinia brasiliensis ("bacupari"). Traditionally known for treating wounds and ulcers, G. brasiliensis presents anti-inflammatory, antioxidant and antimicrobials properties. But, its wound healing profile in experimental models, in order to validate its efficacy, is still litle studied.

AIM OF THE STUDY

Thus, the objective of this work was to evaluate, in an infected cutanous wound model, the potential of formulations incorporated with G. brasiliensis leaves extracts.

MATERIALS AND METHODS

Crude extract (CE), Ethyl Acetate Fraction (EAF) and Hexanic Fraction (HF) were submitted to phytochemical assays, high performance thin layer chromatography (HTPLC) and cytotoxicity studies. CE and EAF were also tested for microbicidal properties and incorporated in cream and gel formulations at 10% concentration. After stability testing, the gel formulations with CE or EAF at 10% were selected and applied to skin wounds infected or not with Staphylococcus aureus in Wistar rats. The healing potenttial of the extracts was verified by the expression of the protein Annexin A1 (AnxA1), related to the processes of inflammation and antifibrotic function, the cells immunostaining for Gasdermin-D (GSDM-D), a marker of pyroptotic cell death, and the dosage of interleukin-10 (IL-10) and monocyte chemotactic protein (MCP)-1 inflammatory mediators.

RESULTS

Phytochemical studies indicated the presence of compounds of pharmacological interest, including Catechin, Quercetin and Berberine in addition to low cytotoxicity of CE and EAF at 10%. After the 6-day topical treatments, CE and EAF gel formulations demonstrated to control the pruritus formation process. The treatments decreased AnxA1 expression and the amount of cells immunostained for GSDM-D, and increased the expression of MCP-1 in infected wounds.

CONCLUSIONS

Together, the results show important anti-inflammatory profile and skin healing potential of CE and EAF from G. brasiliensis leaves, even in infected lesions, with therapeutic perspectives.

Fenugreek Extract-Loaded Polycaprolacton/Cellulose Acetate Nanofibrous Wound Dressings for Transplantation of Unrestricted Somatic Stem Cells: An In Vitro and In Vivo Evaluation

Complex pathophysiology of diabetic wounds causes a delayed wound healing response. Advanced wound dressing materials that deliver biochemical cues are of particular interest in wound healing research. Here, we developed a dual-function delivery vehicle for drug and cell delivery applications to treat diabetic wounds. The delivery system was developed via electrospinning of polycaprolacton/cellulose acetate solution containing fenugreek extract. The produced delivery vehicle was characterized using microstructural studies, cell viability assay, cytoprotection assay, cell migration assay, In Vitro anti-inflammatory assay, free radical scavenging assay, tensile strength studies, swelling studies, and protein adsorption test. Scaffolds were then seeded with 30000 unrestricted somatic stem cells and transplanted into the rat model of excisional diabetic wound. Wound healing assay showed that the co-delivery of fenugreek extract and unrestricted somatic stem cells led to a substantial improvement in the healing activity of electrospun dressings, as evidenced by higher wound contraction, epithelial thickness, and collagen deposition in this group compared with other experimental groups. Gene expression analysis showed that dual-function delivery system could increase the expression level of VEGF, b-FGF, and collagen type II genes. Furthermore, the tissue expression level of IL-1β and glutathione peroxidase genes was significantly reduced in this group compared with other groups. This study shows that the developed system may be considered as a potential treatment modality for diabetic wounds in the clinic.

Encapsulation of berberine decorated ZnO nano-colloids into injectable hydrogel using for diabetic wound healing

Chronic wound healing in diabetic patients had been considered a major clinical challenge, so there was an urgent need to establish more effective treatment methods. In this study, we prepared berberine-modified ZnO nano-colloids hydrogel (ZnO-Ber/H) and evaluated its wound healing performance in a diabetic rat. The prepared ZnO-Ber/H had excellent moisturizing, anti-inflammatory and anti-oxidative stress abilities. In vitro, ZnO-Ber/H could effectively up-regulate antioxidant stress factors (Nrf2, HO-1, NQO1) by 4.65-fold, 2.49-fold, 2.56-fold, respectively. In vivo experiments have shown that ZnO-Ber/H could effectively improve the wound healing rate (92.9%) after 15 days of treatment. Meanwhile, the ability of anti-oxidative stress had also been verified in vivo. ZnO-Ber/H down-regulated inflammatory factor (TNF-α, IL-1β, and IL-6) by 72.8%, 55% and 71% respectively, up-regulated vascular related factors VEGF and CD31 by 3.9-fold and 3.2-fold by Western blot. At the same time, ZnO-Ber/H could promote the expression of EGFR and FGFR, thereby affecting the generation of new epithelial tissue. Based on extensive characterization and biological evaluation, ZnO-Ber/H was expected to be a potential candidate for promoting diabetic wound healing.

Honey-Loaded Reinforced Film Based on Bacterial Nanocellulose/Gelatin/Guar Gum as an Effective Antibacterial Wound Dressing

Recently, the use of bacterial nanocellulose (BNC) produced by Acetobacter, which has suitable properties for tissue engineering application as a perfect wound dressing, has attracted considerable attention. For this purpose, we successfully developed honey loaded BNC-reinforced gelatin/dialdehyde-modified guar gum films (H/BNC/Ge/D-GG). Prepared films were studied for their morphological, thermal stability, mechanical, water solubility and degradability properties. The physicochemical properties of the developed films with or without honey loading were studied. The results indicated that by enhancing the honey content of the film, the degradation behavior, adhesion and proliferation of NIH-3T3 fibroblast cells were improved. The films with 15 wt% of honey revealed inhibition activity against S. aureus (13.0±0.1 mm) and E. coli (15.0±1.0 mm) bacteria. Cell culture results demonstrated that the prepared films had good cytocompatibility. Based on the results, the prepared H/BNC/Ge/D-GG films appear to have high potential for antibacterial wound dressings.

Applications of Electrospun Drug-Eluting Nanofibers in Wound Healing: Current and Future Perspectives

Wounds are a consequence of disruption in the structure, integrity, or function of the skin or tissue. Once a wound is formed following mechanical or chemical damage, the process of wound healing is initiated, which involves a series of chemical signaling and cellular mechanisms that lead to regeneration and/or repair. Disruption in the healing process may result in complications; therefore, interventions to accelerate wound healing are essential. In addition to mechanical support provided by sutures and traditional wound dressings, therapeutic agents play a major role in accelerating wound healing. The medicines known to improve the rate and extent of wound healing include antibacterial, anti-inflammatory, and proliferation enhancing agents. Nonetheless, the development of these agents into eluting nanofibers presents the possibility of fabricating wound dressings and sutures that provide mechanical support with the added advantage of local delivery of therapeutic agents to the site of injury. Herein, the process of wound healing, complications of wound healing, and current practices in wound healing acceleration are highlighted. Furthermore, the potential role of drug-eluting nanofibers in wound management is discussed, and lastly, the economic implications of wounds as well as future perspectives in applying fiber electrospinning in the design of wound dressings and sutures are considered and reported.

Recent Progress in Development of Dressings Used for Diabetic Wounds with Special Emphasis on Scaffolds

Diabetic wound (DW) is a secondary application of uncontrolled diabetes and affects about 42.2% of diabetics. If the disease is left untreated/uncontrolled, then it may further lead to amputation of organs. In recent years, huge research has been done in the area of wound dressing to have a better maintenance of DW. These include gauze, films, foams or, hydrocolloid-based dressings as well as polysaccharide- and polymer-based dressings. In recent years, scaffolds have played major role as biomaterial for wound dressing due to its tissue regeneration properties as well as fluid absorption capacity. These are three-dimensional polymeric structures formed from polymers that help in tissue rejuvenation. These offer a large surface area to volume ratio to allow cell adhesion and exudate absorbing capacity and antibacterial properties. They also offer a better retention as well as sustained release of drugs that are directly impregnated to the scaffolds or the ones that are loaded in nanocarriers that are impregnated onto scaffolds. The present review comprehensively describes the pathogenesis of DW, various dressings that are used so far for DW, the limitation of currently used wound dressings, role of scaffolds in topical delivery of drugs, materials used for scaffold fabrication, and application of various polymer-based scaffolds for treating DW.

Successful Treatment of Bullous Pemphigoid Lesions by Berberine Stamp Therapy: A Case Report and Literature Review

Bullous pemphigoid (BP) is a life-threatening autoimmune disease of the skin that is mainly characterized by a large range of tension blisters and intense itching of the skin. The 1-year mortality rate of BP was 23.5%. Superinfection caused by skin lesion ulceration is one of the important causes of disease death. Therefore, it is challenging to control infection and improve skin wound healing. Here, we report the case of an elderly woman who presented with BP and involved the oral mucosa. The patient was successfully treated with hormones combined with topical berberine, and 95% of the patients’ lesions healed completely after 1 month. In addition, we inductively analyzed the current treatments for BP to provide a reference for BP clinical treatment.

Application of nanotechnology in management and treatment of diabetic wounds

Diabetic wounds are one of the most common health problems worldwide, enhancing the demand for new management strategies. Nanotechnology, as a developing subject in diabetic wound healing, is proving to be a promising and effective tool in treatment and care. It is, therefore, necessary to ascertain the available and distinct nanosystems and evaluate their performance when topically applied to the injury site, especially in diabetic wound healing. Several active ingredients, including bioactive ingredients, growth factors, mesenchymal stem cells, nucleic acids, and drugs, benefit from improved properties when loaded into nanosystems. Given the risk of problems associated with systemic administration, the topical application should be considered, provided stability and efficacy are assured. After nanoencapsulation, active ingredients-loaded nanosystems have been showing remarkable features of biocompatibility, healing process hastening, angiogenesis, and extracellular matrix compounds synthesis stimulation, contributing to a decrease in wound inflammation. Despite limitations, nanotechnology has attracted widespread attention in the scientific community and seems to be a valuable technological ally in the treatment and dressing of diabetic wounds. The use of nanotechnology in topical applications enables efficient delivery of the active ingredients to the specific skin site, increasing their bioavailability, stability, and half-life time, without compromising their safety.

Electrospun polycaprolactone nanofibrous membranes loaded with baicalin for antibacterial wound dressing

Due to the rise in bacterial resistance, the antibacterial extractions from Chinese herbs have been used more frequently for wound care. In this work, baicalin, an extraction from the Chinese herb Scutellaria baicalensis, was utilized as the antibacterial component in the poly(ε-caprolactone)/MXene (PCL/Ti₃C₂T_X) hybrid nanofibrous membranes for wound dressing. The results revealed that the presence of Ti₃C₂T_X aided in the diameter reduction of the electrospun nanofibers. The PCL hybrid membrane containing 3 wt% Ti₃C₂T_X nanoflakes and 5 wt% baicalin exhibited the smallest mean diameter of 210 nm. Meanwhile, the antibacterial tests demonstrated that the PCL ternary hybrid nanofibers containing Ti₃C₂T_X and baicalin exhibited adequate antibacterial activity against the Gram-positive bacterial S. aureus due to the good synergistic effects of Ti₃C₂T_X naoflakes and baicalin. The addition of Ti₃C₂T_X nanoflakes and baicalin could significantly improve the hydrophilicity of the membranes, resulting in the release of baicalin from the nanofibers. In addition, the cytotoxicity of the nanofibers on rat skeletal myoblast L6 cells confirmed their good compatibility with these PCL-based nanofibrous membrances. This work offers a feasible way to prepare antibacterial nanofibrous membranes using Chinese herb extraction for wound dressing applications.

Fabrication of Gelatin Nanofibers by Electrospinning-Mixture of Gelatin and Polyvinyl Alcohol

Gelatin, one of the most abundant, naturally derived biomacromolecules from collagen, is widely applicable in food additives, cosmetic ingredients, drug formulation, and wound dressing based on their non-toxicity and biodegradability. In parallel, polyvinyl alcohol (PVA), a synthetic polymer, has been commonly applied as a thickening agent for coating processes in aqueous systems and a major component in healthcare products for cartilage replacements, eye lubrication, and contact lenses. In this study, a new type of mixed hydrogel nanofiber was fabricated from gelatin and polyvinyl alcohol by electrospinning under a feasible range of polymer compositions. To determine the optimal composition of gelatin and polyvinyl alcohol in nanofiber fabrication, several key physicochemical properties of mixed polymer solutions such as viscosity, surface tension, pH, and electrical conductance were thoroughly characterized by a viscometer, surface tensiometer, water analyzer, and carbon electron probe. Moreover, the molecular structures of polymeric chains within mixed hydrogel nanofibers were investigated with Fourier-transform infrared spectroscopy. The morphologies and surface elemental compositions of the mixed hydrogel nanofibers were examined by the scanning electron microscope and energy-dispersive X-ray spectroscopy, respectively. The measurement of water contact angles was performed for measuring the hydrophilicity of nanofiber surfaces. Most importantly, the potential cytotoxicity of the electrospun nanofibers was evaluated by the in vitro culture of 3T3 fibroblasts. Through our extensive study, it was found that a PVA-rich solution (a volumetric ratio of gelatin/polyvinyl alcohol <1) would be superior for the efficient production of mixed hydrogel nanofibers by electrospinning techniques. This result is due to the appropriate balance between the higher viscosity (~420−~4300 10−2 poise) and slightly lower surface tension (~35.12−~32.68 mN/m2) of the mixed polymer solution. The regression on the viscosity data also found a good fit by the Lederer−Rougier’s model for a binary mixture. For the hydrophilicity of nanofibers, the numerical analysis estimates that the value of interfacial energy for the water contact on nanofibers is around ~−0.028 to ~−0.059 J/m2.

Electrospun nanofibers based on carboxymethyl cellulose/polyvinyl alcohol as a potential antimicrobial wound dressing

In this work, citric acid-based quantum dots (CA-QDs) as a novel and safe crosslinked agent was applied in different feeding ratios (5-15 wt%) to synthesize carboxymethyl cellulose/polyvinyl alcohol (CMC/PVA) nanofibers (NFs) for the first time. Colistin (CL) as an antibacterial agent was also loaded (2 w/w%) during the synthesizing process of CMC/PVA electrospun NFs to trigger antimicrobial properties. The morphological, hydrophilic, and mechanical properties of the prepared NFs were fully investigated with different techniques. The electrospun NFs with crosslinking ratios of 10 wt% CA-QDs revealed appropriate mechanical properties. According to cell culture data, the prepared NFs demonstrated good cytocompatibility against HFF-1 cells (over 80% cell viability). Remarkably, CL-loaded NFs showed desired antibacterial efficacy against S. aureus, E. coli, K. pneumoniae, and P. aeruginosa with 1.0-1.4, 1.3-1.4, 0.8-1.0, and 1.3-1.5 cm inhibition zones, respectively. These outcomes suggested that the fabricated NFs can be useful as wound healing scaffolds.

Polyethylenimine-Functionalized Nanofiber Nonwovens Electrospun from Cotton Cellulose for Wound Dressing with High Drug Loading and Sustained Release Properties

Electrospun cellulose nanofiber nonwovens have shown promise in wound dressing owing to the highly interconnected pore structure, high hydrophilicity coupled with other coveted characteristics of biodegradability, biocompatibility and renewability. However, electrospun cellulose wound dressings with loaded drugs for better wound healing have been rarely reported. In this study, a novel wound dressing with a high drug loading capacity and sustained drug release properties was successfully fabricated via electropinning of cellulose followed by polyethylenimine (PEI)-functionalization. Remarkably, the grafted PEI chains on the surface of electrospun cellulose nanofibers provided numerous active amino groups, while the highly porous structure of nonwovens could be well retained after modification, which resulted in enhanced adsorption performance against the anionic drug of sodium salicylate (NaSA). More specifically, when immersed in 100 mg/L NaSA solution for 24 h, the as-prepared cellulose-PEI nonwoven displayed a multilayer adsorption behavior. And at the optimal pH of 3, a high drug loading capacity of 78 mg/g could be achieved, which was 20 times higher than that of pristine electrospun cellulose nonwoven. Furthermore, it was discovered that the NaSA-loaded cellulose-PEI could continuously release the drug for 12 h in simulated body fluid (SBF), indicating the versatility of cellulose-PEI as an advanced wound dressing with drug carrier functionalities.