A Multifunctional Janus Electrospun Nanofiber Dressing with Biofluid Draining, Monitoring, and Antibacterial Properties for Wound Healing

A Highly Stable, Multifunctional Janus Dressing for Treating Infected Wounds

The limited and unstable absorption of excess exudate is a major challenge during the healing of infected wounds. In this study, a highly stable, multifunctional Janus dressing with unidirectional exudate transfer capacity is fabricated based on a single poly(lactide caprolactone) (PLCL). The success of this method relies on an acid hydrolysis reaction that transforms PLCL fibers from hydrophobic to hydrophilic in situ. The resulting interfacial affinity between the hydrophilic/phobic PLCL fibers endows the Janus structure with excellent unidirectional liquid transfer and high structural stability against repeated stretching, bending, and twisting. Various other functions, including wound status detection, antibacterial, antioxidant, and anti-inflammatory properties, are also integrated into the dressing by incorporating phenol red and epigallocatechin gallate. An in vivo methicillin-resistant Staphylococcus aureus-infected wound model confirms that the Janus dressing, with the capability to remove exudate from the infected site, not only facilitates epithelialization and collagen deposition, but also ensures low inflammation and high angiogenesis, thus reaching an ideal closure rate up to 98.4% on day 14. The simple structure, multiple functions, and easy fabrication of the dressing may offer a promising strategy for treating chronic wounds, rooted in the challenges of bacterial infection, excessive exudate, and persistent inflammation.

Synergistic Biofilter Tube for Promoting Scarless Tendon Regeneration

Inspired by the imbalance between extrinsic and intrinsic tendon healing, this study fabricated a new biofilter scaffold with a hierarchical structure based on a melt electrowriting technique. The outer multilayered fibrous structure with connected porous characteristics provides a novel passageway for vascularization and isolates the penetration of scar fibers, which can be referred to as a biofilter process. In vitro experiments found that the porous architecture in the outer layer can effectively prevent cell infiltration, whereas the aligned fibers in the inner layer can promote cell recruitment and growth, as well as the expression of tendon-associated proteins in a simulated friction condition. It was shown in vivo that the biofilter process could promote tendon healing and reduce scar invasion. Herein, this novel strategy indicates great potential to design new biomaterials for balancing extrinsic and intrinsic healing and realizing scarless tendon healing.

A unidirectional water-transport antibacterial bilayer nanofibrous dressing based on chitosan for accelerating wound healing

Excessive accumulation of exudate from wounds often causes infection and hinders skin regeneration. To handle wound exudate quickly and prevent infection, we developed an antibacterial Janus nanofibrous dressing with a unidirectional water-transport function. The dressing consists of a hydrophilic chitosan aerogel (CS-A) as the outer layer and a hydrophobic laurylated chitosan (La-CS) nanofibrous membrane as the inner layer. These dressings achieved excellent liquid absorption performance (2987.8 ± 123.5 %), air and moisture permeability (997.8 ± 23.1 g/m2/day) and mechanical strength (5.1 ± 2.6 MPa). This performance was obtained by adjusting the density of CS-A and the thickness of the La-CS membrane. Moreover, the dressing did not induce significant toxicity to cells and can prevent bacterial aggregation and infection at the wound site. Animal experiments showed that the dressing can shorten the inflammatory phase, enhance blood vessel generation, and accelerate collagen deposition, thus promoting wound healing. Overall, these results suggest that this Janus dressing is a promising material for clinical wound care.

Carboxymethyl chitosan-based hydrogel-Janus nanofiber scaffolds with unidirectional storage-drainage of biofluid for accelerating full-thickness wound healing

Self-pumping wound scaffolds designed for directional biofluid transport are extensively investigated. They efficiently extract excessive biofluids from wounds, while maintaining an optimally humid wound environment, thus facilitating rapid wound healing. However, the existing designed scaffolds are insufficiently focused on stimulating the hydrophobic layer at the wound site, thereby exacerbating inflammation and impeding the wound healing process. Herein, we engineered and fabricated a hydrophilic-hydrophobic-hydrophilic sandwich-structured hydrogel-Janus nanofiber scaffold (NFS) employing a Layer-by-Layer (LbL) method. This scaffold comprises a hydrophilic carboxymethyl chitosan/silver (CMCS-Ag) hydrogel component in conjunction with a poly(caprolactone)/poly(caprolactone)-poly(citric acid)-co-ε-polylysine (PCL/PCL-PCE) Janus NFS. It is noteworthy that the hydrogel-Janus nanofiber scaffold not only demonstrates outstanding water absorption (202.2 %) and unidirectional biofluid transport capability but also possesses high breathability (308.663 m3/m2 h kPa), appropriate pore size (6.7-7.5 μm), excellent tensile performance (270 ± 10 %), and superior mechanical strength (26.36 ± 1.77 MPa). Moreover, in vitro experimentation has convincingly demonstrated the impeccable biocompatibility of hydrogel-Janus NFS. The inherent dual-antibacterial properties in CMCS-Ag and PCE significantly augment fibroblast proliferation and migration. In vivo studies further underscore its capability to expedite wound healing by absorption and expulsion of wound exudates, thereby fostering collagen deposition and vascularization. As such, this work potentially provides fresh insights into the design and fabrication of multifunctional biomimetic scaffolds, holding immense potential in the medical field for efficient wound healing.

Preparation of pH-sensitive porous polylactic acid-based medical dressing with self-pumping function

Excessive exudation from the wound site and the difficulty of determining the state of wound healing can make medical management more difficult and, in extreme cases, lead to wound deterioration. In this study, we fabricated a pH-sensitive colorimetric chronic wound dressing with self-pumping function using electrostatic spinning technology. It consisted of three layers: a polylactic acid-curcumin (PCPLLA) hydrophobic layer, a hydrolyzed polyacrylonitrile (HPAN) transfer layer, and a polyacrylonitrile-purple kale anthocyanin (PAN-PCA) hydrophilic layer. The results showed that the preparation of porous PLLA fiber membrane loaded with 0.2 % Cur was achieved by adjusting the spinning-related parameters, which could ensure that the composite dressing had sufficient anti-inflammatory, antibacterial and antioxidant properties. The HPAN membrane treated with alkali for 30 min had significantly enhanced liquid wetting ability, and the unidirectional transport of liquid could be achieved by simple combination with the 20 um PCPLLA fiber membrane. In addition, the 4 % loaded PCA showed more obvious color difference than the colorimetric membrane. In vivo and ex vivo experiments have demonstrated the potential of multifunctional dressings for the treatment of chronic wounds.

Extracellular Matrix-Bioinspired Anisotropic Topographical Cues of Electrospun Nanofibers: A Strategy of Wound Healing through Macrophage Polarization

The skin serves as the body's outermost barrier and is the largest organ, providing protection not only to the body but also to various internal organs. Owing to continuous exposure to various external factors, it is susceptible to damage that can range from simple to severe, including serious types of wounds such as burns or chronic wounds. Macrophages play a crucial role in the entire wound-healing process and contribute significantly to skin regeneration. Initially, M1 macrophages infiltrate to phagocytose bacteria, debris, and dead cells in fresh wounds. As tissue repair is activated, M2 macrophages are promoted, reducing inflammation and facilitating restoration of the dermis and epidermis to regenerate the tissue. This suggests that extracellular matrix (ECM) promotes cell adhesion, proliferation, migrationand macrophage polarization. Among the numerous strategies, electrospinning is a versatile technique for obtaining ECM-mimicking structures with anisotropic and isotropic topologies of micro/nanofibers. Various electrospun biomaterials influence macrophage polarization based on their isotropic or anisotropic topologies. Moreover, these fibers possess a high surface-area-to-volume ratio, promoting the effective exchange of vital nutrients and oxygen, which are crucial for cell viability and tissue regeneration. Micro/nanofibers with diverse physical and chemical properties can be tailored to polarize macrophages toward skin regeneration and wound healing, depending on specific requirements. This review describes the significance of micro/nanostructures for activating macrophages and promoting wound healing.

Preparation and properties of polyvinyl alcohol/chitosan-based hydrogel with dual pH/NH3 sensor for naked-eye monitoring of seafood freshness

To address the issue of food spoilage causing health and economic loss, we developed a pH/NH3 dual sensitive hydrogel based on polyvinyl alcohol/chitosan (PVA/CS) containing chitosan-phenol red (CP). The CP was synthesized via Mannich reaction and immobilized it in PVA/CS hydrogel through freezing/thawing method to prepare the final PVA/CS/CP hydrogel. The synthesis of CP was confirmed by 1H NMR, FT-IR, XRD, UV-vis, and XPS. The characteristics of hydrogel were evaluated by FT-IR, XRD, SEM, mechanical properties, thermal stability, leaching, and color stability tests. The PVA/CS/CP hydrogel showed distinctly different color at various pH and NH3 vapor levels (yellow to purple). The hydrogel exhibited obvious color changes (ΔE = 46.95) in response to shrimp spoilage, stored at 4 °C. It showed positive and strong correlation between the ΔE values of the indicator hydrogel and total volatile basic nitrogen (TVB-N) as (R2 = 0.9573) and with pH as (R2 = 0.8686), respectively. These results clearly show that the PVA/CS/CP hydrogel could be applied for naked-eye real-time monitoring of seafood freshness in intelligent packaging.

Multi-functional composite dressings with sustained release of MSC-SLP and anti-adhesion property for accelerating wound healing

Exudate management is of significant clinical value for the treatment of acute wound. Various wound dressings have been developed to restore the function of injured tissues and promote wound healing, but proper exploiting the healing factors inside exudate and achieving anti-adhesion wound care remains a challenge. Herein, we present a novel multi-functional composite dressing (MCD) by coupling supernatant lyophilized powder of mesenchymal stem cells (MSC-SLP) with a sandwich-structured wound dressing (SWD). The developed MCDs demonstrated unique unidirectional drainage capability, stable anti-adhesion characteristics, and improved wound healing performance. The designed SWD with both superhydrophobic inner surface and liquid-absorption ability of mid layer enables the dressings exhibit desired anti-adhesion property to neoformative granulation tissues, favorable shielding effect to exogenous bacteria, as well as appropriate exudate-retaining capability and unidirectional exudate-absorption property. The introduction of MSC-SLP in SWD was demonstrated to further improve wound healing quality. Compared to medical gauze, the synergic effect of SWD and MSC-SLP significantly accelerates wound healing rate by over 30%, avoids tissue avulsion when changing dressings, and produces a flat-smooth closure surface. More importantly, the wound treated with MCDs presents more skin accessory organs and blood vessels in regenerated tissues than other groups. In vivo/vitro biocompatibility evaluations indicated little toxicity, demonstrating the biosecurity of the developed dressings. The proposed method offers great potential in clinical applications particularly for chronic wound treatments.

Robust Gradient Hydrogel-Loaded Nanofiber Fleshy Artificial Skin Via A Coupled Microfluidic Electrospinning-Reactive Coating Strategy

Skin regeneration attracts tremendous interest due to the important role of skin for human protection and beauty. Thus, methods allowing artificial skin to be carried out in a controllable fashion are potentially important for wound healing, which involves an intersection of materials, medicine, biology, and other disciplines. Herein, aiming at a new general methodology for fleshy materials, a new hydrogel-loaded hydrophobic-hydrophilic nanofiber fleshy artificial skin is designed and fabricated. The gradient hydrogel-loaded nanofiber artificial skin integrates both advantages of nanofiber and hydrogel, exhibiting fleshy feature (comparability to real skin in terms of appearance, texture, and function), excellent air permeability, compatibility, and good mechanical and antibacterial property. Interestingly, the efficient transport channels are formed throughout the hydrogel-loaded nanofiber structure, which is beneficial for water absorption and transfer. These advantages enable the establishment of a moist and favorable microenvironment; thus, greatly accelerating wound healing process. This work couples microfluidic electrospinning with reactive coating technique, which is in favor of material design and fabrication with controllable and uniform structures. The hydrogel-loaded nanofiber fleshy artificial skin shows comparability to real skin in terms of beauty, texture, and function, which would definitely provide new opportunities for the further optimization and upgrading of artificial skin.

Flexible Accelerated-Wound-Healing Antibacterial Hydrogel-Nanofiber Scaffold for Intelligent Wearable Health Monitoring

Flexible epidermal sensors hold significant potential in personalized healthcare and multifunctional electronic skins. Nonetheless, achieving both robust sensing performance and efficient antibacterial protection, especially in medical paradigms involving electrophysiological signals for wound healing and intelligent health monitoring, remains a substantial challenge. Herein, we introduce a novel flexible accelerated-wound-healing biomaterial based on a hydrogel-nanofiber scaffold (HNFS) via electrostatic spinning and gel cross-linking. We effectively engineer a multifunctional tissue nanoengineered skin scaffold for wound treatment and health monitoring. Key features of HNFS include high tensile strength (24.06 MPa) and elasticity (214.67%), flexibility, biodegradability, and antibacterial properties, enabling assembly into versatile sensors for monitoring human motion and electrophysiological signals. Moreover, in vitro and in vivo experiments demonstrate that HNFS significantly enhances cell proliferation and skin wound healing, provide a comprehensive therapeutic strategy for smart sensing and tissue repair, and guide the development of high-performance "wound healing-health monitoring" bioelectronic skin scaffolds. Therefore, this study provides insights into crafting flexible and repairable skin sensors, holding potential for multifunctional health diagnostics and intelligent medical applications in intelligent wearable health monitoring and next-generation artificial skin fields.

Functional electrospun nanofibers: fabrication, properties, and applications in wound-healing process

Electrostatic spinning as a technique for producing nanoscale fibers has recently attracted increasing attention due to its simplicity, versatility, and loadability. Nanofibers prepared by electrostatic spinning have been widely studied, especially in biomedical applications, because of their high specific surface area, high porosity, easy size control, and easy surface functionalization. Wound healing is a highly complex and dynamic process that is a crucial step in the body's healing process to recover from tissue injury or other forms of damage. Single-component nanofibers are more or less limited in terms of structural properties and do not fully satisfy various needs of the materials. This review aims to provide an in-depth analysis of the literature on the use of electrostatically spun nanofibers to promote wound healing, to overview the infinite possibilities for researchers to tap into their biomedical applications through functional composite modification of nanofibers for advanced and multifunctional materials, and to propose directions and perspectives for future research.

3-Diethylaminopropyl isothiocyanate modified glycol chitosan for constructing mild-acid sensitive electrospinning antibacterial nanofiber membrane

Bacterial infections would cause pathological inflammation and even generate chronic wound. Herein, a ciprofloxacin (Cip)-loaded mild acid-responsive electrospinning nanofiber membrane (NFM) containing 3-diethylaminopropyl isothiocyanate material grafted glycol chitosan (GC-DEAP) was fabricated to prevent bacterial infection against hemostatic and inflammatory phases of wounds. The presence of Cip and GC-DEAP in the objective NFM (PCL/GC-DEAP/Cip) was confirmed through XRD and FTIR. Meanwhile, PCL/GC-DEAP/Cip NFM exhibited high mechanical profiles, suitable water absorption and water vapour transmission ratio. The non-protonated amphiphilic GC-DEAP under pH 7.4 facilitated the formation of uniform and smooth nanofibers with polycaprolactone (PCL) and Cip. However, the GC-DEAP was demonstrated to sharply respond to the mild-acid environment of the wound and effectively be protonated, and thus improved the swelling ability of NFM and triggered burst release of Cip. Due to the combination between protonated GC-DEAP and Cip, PCL/GC-DEAP/Cip NFM achieved attractive antibacterial activity in the mild-acid environment in vitro, and induced more efficient prevention of wound infection and faster wound healing compared with the commercial chitosan dressing. The designed NFM is expected to be a potential smart wound dressing against hemostatic and inflammatory phases with mild-acid specifically strengthened antibacterial features and satisfactory biocompatibility.

A sandwich-like silk fibroin/polysaccharide composite dressing with continual biofluid draining for wound exudate management

Optimal wound healing requires a wet microenvironment without over-hydration. Inspired by capillarity and transpiration, we have developed a sandwich-like fibers/sponge dressing with continuous exudate drainage to maintain appropriate wound moisture. This dressing is prepared by integrating a three-layer structure using the freeze-drying method. Layer I, as the side that contacts with the skin directly, consists of a hydrophobic silk fibroin membrane; Layer II, providing the pumping action, is made of superabsorbent chitosan-konjac glucomannan sponge; Layer III, accelerating evaporation sixfold compared to natural evaporation, is constructed with a graphene oxide soaked hydrophilic cellulose acetate membrane. Animal experiments showed that the composite dressing had superior wound-healing characteristics, with wounds decreasing to 24.8% of their original size compared to 28.5% for the commercial dressing and 43.2% for the control. The enhanced wound healing can be ascribed to the hierarchical porous structure serves as the fluid-driving factor in this effort; the hydrophilicity of a membrane composed of silk fibroin nanofibers is adjustable to regulate fluid-transporting capacity; and the photothermal effect of graphene oxide guarantees exudates that have migrated to the top layer to evaporate continuously. These findings indicate the unidirectional wicking dressing has the potential to become the next generation of clinical dressings.

Hydrogen sulfide releasing poly(γ-glutamic acid) biocomposite hydrogel with monitoring, antioxidant, and antibacterial properties for diabetic wound healing

Adverse factors such as high levels of glucose, oxidative stress, inflammation, and bacterial infection impede diabetic wound healing and even worsen wounds. Owing to its outstanding anti-inflammatory and antioxidant properties as well as the potential to promote cell migration and proliferation, hydrogen sulfide(H2S) gas therapy is promising for chronic diabetic wound recovery. In this work, a multifunctional poly(γ-glutamic acid)(PGA) hydrogel encapsulated with keratin-based H2S donor(KTC), ciprofloxacin(Cip), and anthocyanins(Ant) was developed. The resultant hydrogel was capable of releasing H2S, thereby promoting cell proliferation and enhancing anti-inflammation and antioxidant activity. The release of antibiotic Cip was accelerated under a diabetic wound microenvironment, thereby enhancing the antibacterial activity of the hydrogel. The encapsulated Ant could serve as a pH monitor, sensitively indicating wound pH conditions in situ and indirectly reflecting wound infection. In vivo results in diabetic wound healing suggested that PGA/Ant/KTC/Cip hydrogel reduced inflammation and promoted angiogenesis and collagen deposition, thereby accelerating wound healing.

Multifunctional and theranostic hydrogels for wound healing acceleration: An emphasis on diabetic-related chronic wounds

Hydrogels represent intricate three-dimensional polymeric structures, renowned for their compatibility with living systems and their ability to naturally degrade. These networks stand as promising and viable foundations for a range of biomedical uses. The practical feasibility of employing hydrogels in clinical trials has been well-demonstrated. Among the prevalent biomedical uses of hydrogels, a significant application arises in the context of wound healing. This intricate progression involves distinct phases of inflammation, proliferation, and remodeling, often triggered by trauma, skin injuries, and various diseases. Metabolic conditions like diabetes have the potential to give rise to persistent wounds, leading to delayed healing processes. This current review consolidates a collection of experiments focused on the utilization of hydrogels to expedite the recovery of wounds. Hydrogels have the capacity to improve the inflammatory conditions at the wound site, and they achieve this by diminishing levels of reactive oxygen species (ROS), thereby exhibiting antioxidant effects. Hydrogels have the potential to enhance the growth of fibroblasts and keratinocytes at the wound site. They also possess the capability to inhibit both Gram-positive and Gram-negative bacteria, effectively managing wounds infected by drug-resistant bacteria. Hydrogels can trigger angiogenesis and neovascularization processes, while also promoting the M2 polarization of macrophages, which in turn mitigates inflammation at the wound site. Intelligent and versatile hydrogels, encompassing features such as pH sensitivity, reactivity to reactive oxygen species (ROS), and responsiveness to light and temperature, have proven advantageous in expediting wound healing. Furthermore, hydrogels synthesized using environmentally friendly methods, characterized by high levels of biocompatibility and biodegradability, hold the potential for enhancing the wound healing process. Hydrogels can facilitate the controlled discharge of bioactive substances. More recently, there has been progress in the creation of conductive hydrogels, which, when subjected to electrical stimulation, contribute to the enhancement of wound healing. Diabetes mellitus, a metabolic disorder, leads to a slowdown in the wound healing process, often resulting in the formation of persistent wounds. Hydrogels have the capability to expedite the healing of diabetic wounds, facilitating the transition from the inflammatory phase to the proliferative stage. The current review sheds light on the biological functionalities of hydrogels, encompassing their role in modulating diverse mechanisms and cell types, including inflammation, oxidative stress, macrophages, and bacteriology. Additionally, this review emphasizes the significance of smart hydrogels with responsiveness to external stimuli, as well as conductive hydrogels for promoting wound healing. Lastly, the discussion delves into the advancement of environmentally friendly hydrogels with high biocompatibility, aimed at accelerating the wound healing process.

The colorful world of sulfonephthaleins: Current applications in analytical chemistry for "old but gold" molecules

Sulfonephthaleins represent one of the most common and widely employed reactive dyes in analytical chemistry, thanks to their stability, low-cost, well-visible colors, reactivity and possibilities of chemical modification. Despite being first proposed in 1916, nowadays, these molecules play a fundamental role in biological and medical applications, environmental analyses, food quality monitoring and other fields, with a particular focus on low-cost and disposable devices or methods for practical applications. Since up to our knowledge, no reviews or book chapters focused explicitly on sulfonephthaleins have ever been published, in this review, we will briefly describe sulfonephthaleins history, their acid-base properties will be discussed, and the most recent applications in different fields will be presented, focusing on the last ten years literature (2014-2023). Finally, safety and environmental issues will be briefly discussed, despite being quite controversial.

Recent Progress in Stimuli-Responsive Antimicrobial Electrospun Nanofibers

Electrospun nanofibrous membranes have garnered significant attention in antimicrobial applications, owing to their intricate three-dimensional network that confers an interconnected porous structure, high specific surface area, and tunable physicochemical properties, as well as their notable capacity for loading and sustained release of antimicrobial agents. Tailoring polymer or hybrid-based nanofibrous membranes with stimuli-responsive characteristics further enhances their versatility, enabling them to exhibit broad-spectrum or specific activity against diverse microorganisms. In this review, we elucidate the pivotal advancements achieved in the realm of stimuli-responsive antimicrobial electrospun nanofibers operating by light, temperature, pH, humidity, and electric field, among others. We provide a concise introduction to the strategies employed to design smart electrospun nanofibers with antimicrobial properties. The core section of our review spotlights recent progress in electrospun nanofiber-based systems triggered by single- and multi-stimuli. Within each stimulus category, we explore recent examples of nanofibers based on different polymers and antimicrobial agents. Finally, we delve into the constraints and future directions of stimuli-responsive nanofibrous materials, paving the way for their wider application spectrum and catalyzing progress toward industrial utilization.

Phase Change Material-Embedded Multifunctional Janus Nanofiber Dressing with Directional Moisture Transport, Controlled Release of Anti-Inflammatory Drugs, and Synergistic Antibacterial Properties

Wound healing is a systematic and complex process that involves various intrinsic and extrinsic factors affecting different stages of wound repair. Therefore, multifunctional wound dressings that can modulate these factors to promote wound healing are in high demand. In this work, a multifunctional Janus electrospinning nanofiber dressing with antibacterial and anti-inflammatory properties, controlled release of drugs, and unidirectional water transport was prepared by depositing coaxial nanofibers on a hydrophilic poly(ε-caprolactone)@polydopamine-ε-polyl-lysine (PCL@PDA-ε-PL) nanofiber membrane. The coaxial nanofiber was loaded with the phase change material lauric acid (LA) in the shell layer and anti-inflammatory ibuprofen (IBU) in the core layer. Among them, LA with a melting point of 43 °C served as a phase change material to control the release of IBU. The phase transition of LA was induced by near-infrared (NIR) irradiation that triggered the photothermal properties of PDA. Moreover, the Janus nanofiber dressing exhibited synergistic antimicrobial properties for Escherichia coli and Staphylococcus aureus due to the photothermal properties of PDA and antibacterial ε-PL. The prepared Janus nanofiber dressing also exhibited anti-inflammatory activity and biocompatibility. In addition, the Janus nanofiber dressing had asymmetric wettability that enabled directional water transport, thereby draining excessive wound exudate. The water vapor transmission test indicated that the Janus nanofiber dressing had good air permeability. Finally, skin wound healing evaluation in rats confirmed its efficacy in promoting wound healing. Therefore, this strategy of designing and manufacturing a multifunctional Janus nanofiber dressing had great potential in wound healing applications.

Antibacterial and bioactive multilayer electrospun wound dressings based on hyaluronic acid and lactose-modified chitosan

Antibacterial multilayer electrospun matrices based on hyaluronic acid (HA) and a lactose-modified chitosan (CTL) were synthetized (i) by combining electrospun polycaprolactone (PCL) and polysaccharidic matrices in a bilayer device and (ii) by sequentially coating the PCL mat with CTL and HA. In both cases, the antibacterial activity was provided by loading rifampicin within the PCL support. All matrices disclosed suitable morphology and physicochemical properties to be employed as wound dressings. Indeed, both the bilayer and coated fibers showed an optimal swelling capacity (3426 ± 492 % and 1435 ± 251 % after 7 days, respectively) and water vapor permeability (160 ± 0.78 g/m2h and 170 ± 12 g/m2h at 7 days, respectively). On the other hand, the polysaccharidic dressings were completely wettable in the presence of various types of fluids. Depending on the preparation method, a different release of both polysaccharides and rifampicin was detected, and the immediate polysaccharide dissolution from the bilayer structure impacted the antibiotic release (42 ± 4 % from the bilayer structure against 25 ± 2 % from the coated fibers in 4 h). All the multilayer matrices, regardless of their production strategy and composition, revealed optimal biocompatibility and bioactivity with human dermal fibroblasts, as the released bioactive polysaccharides induced a faster wound closure in the cell monolayer (100 % in 24 h) compared to the controls (78 ± 8 % for untreated cells and 89 ± 5 % for cells treated with PCL alone, after 24 h). The inhibitory and bactericidal effects of the rifampicin loaded matrices were assessed on S. aureus, S. epidermidis, E. coli, and P. aeruginosa. The antibacterial matrices were found to be highly effective except for E. coli, which was more resistant even at higher amounts of rifampicin, with a bacterial concentration of 6.4 ± 0.4 log CFU/mL and 6.8 ± 0.3 log CFU/mL after 4 h in the presence of the rifampicin-loaded bilayer and coated matrices, respectively.

Janus functional electrospun polyurethane fibrous membranes for periodontal tissue regeneration

The guided tissue regeneration (GTR) technique with GTR membranes is an efficient method for repairing periodontal defects. Conventional periodontal membranes act as physical barriers that resist the growth of fibroblasts, epithelial cells, and connective tissue. However, they cannot facilitate the regeneration of periodontal tissue. To address this issue, the exploitation of novel GTR membranes with bioactive functions based on therapeutic requirements is critical. Herein, we exploited a biodegradable bilayer polyurethane fibrous membrane by uniaxial electrostatic spinning to construct two sides with Janus properties by integrating the bioactive molecule dopamine (DA) and antimicrobial Gemini quaternary ammonium salt (QAS). The DA-containing side, located inside the injury, can effectively promote cell adhesion and mesenchymal stem cell growth as well as support mineralization and antioxidant properties, which are beneficial for bone regeneration. The QAS-containing side, located on the outer surface of the injury, endows antibacterial properties and limits fibroblast adhesion and growth on its surface owing to its strong hydrophilicity. An in vivo study demonstrates that the Janus polyurethane fibrous membrane can significantly promote the regeneration of periodontal defects in rats. Owing to its superior mechanical properties and biocompatibility, this polyurethane fibrous membrane has potential applications in the field of periodontal regeneration.

Microenvironment-responsive Cu-phenolic networks coated nanofibrous dressing with timely macrophage phenotype transition for chronic MRSA infected wound healing

Methicillin-resistant Staphylococcus aureus (MRSA) infection is a pressing clinical issue that impedes wound healing. Pro-inflammatory M1 macrophages is required to clear bacteria and recruit various cell types during the initial phase of wound healing, but timing of this process is crucial. Herein, a microenvironment-responsive nanofibrous dressing capable of timely macrophage phenotype transition in vivo is constructed by coating copper ions (Cu2+)-polydopamine (PDA) networks on poly (ε-caprolactone) fiber (PCL-fiber) membrane. During the initial post-implantation period, the nanofibrous dressing show pH-sensitive Cu2+ release in the acidic infection microenvironment. The release Cu2+ have a direct killing effect on MRSA, and promote the proinflammatory M1 phenotype of macrophages to enhance the antibacterial macrophage response. Later, PDA to become a reactive oxygen species (ROS) scavenger when in microenvironments with elevated ROS levels, which conferred the dressing with an immunomodulatory activity that convert M1 macrophages into M2 macrophages. In vivo examination in an MRSA infected full-thickness skin wounds of rat model demonstrates that this dressing significantly facilitated infection eradication and wound healing through modulating local inflammatory phenotype. Overall, this study offers a simple and effective approach for timely manipulation of inflammation progression to promote infected wound healing.

A multifunctional PAN/PVP nanofiber sponge wound dressing loaded with ZIF-8-derived carbon nanoparticles with adjustable wetness for rapid wound disinfection and exudate management

Rapid and safe disinfection and exudate management are two major challenges in infected wound care. Therefore, in this work, we developed a novel wound dressing via encapsulating ZIF-8-derived carbon nanoparticles in a hydrophilic nanofiber sponge to address severe wound infection and heavy exudate problems. The dressing can effectively kill bacteria through chemo-photothermal synergistic therapy. Meanwhile, the hydrophilic nanofiber sponge can quickly absorb wound exudate around the wound and accelerate the evaporation rate of liquid through the photothermal effect and its own structure; therefore, it is possible to remove excess liquid and regulate its wetness. In this way, it prevents the problem of wound overhydration often caused by hydrophilic dressings. In our experiment, the dressing showed good antibacterial performance and biocompatibility in vitro and could effectively control wound infection, absorb wound exudate and promote skin wound healing in vivo. Its good therapeutic effect is not only due to effective infection control and wound exudate management, but also because the structure of nanofibers similar to an extracellular matrix provides basic physical support and structural  signals conducive to skin tissue regeneration.

Multifunctional xyloglucan-containing electrospun nanofibrous dressings for accelerating infected wound healing

Preventing wound infection is a major challenge in biomedicine. Conventional wound dressings often have poor moisturizing and antimicrobial properties unfavorable for wound healing. In this study, we prepared a multifunctional electrospun nanofiber dressing (PCQX-M) containing xyloglucan, quaternized chitosan, Polyvinyl alcohol, and collagen. By applying the concept of wet healing, xyloglucan and quaternized chitosan polysaccharides with excellent water solubility were employed to improve the absorption and moisturizing properties and maintain a moist microenvironment for the wound healing process. PCQX-M demonstrated high mechanical, thermodynamic, and biocompatible properties, providing suitable healing conditions for wounds. In addition, PCQX-M showed exceptional antibacterial properties and a potential inhibitory effect on the growth of microorganisms in infected wounds. More intriguingly, the restorative healing effect was investigated on a mouse model of whole skin injury infected with Staphylococcus aureus. Wound healing, collagen deposition, and immunofluorescence results showed that PCQX-M significantly promoted cell proliferation and angiogenesis at the injury site and facilitated the healing of the infected wound. Our study suggests that PCQX-M has excellent potential for clinical application in infected wound healing.

Tuning foreign body response with tailor-engineered nanoscale surface modifications: fundamentals to clinical applications

Biomaterials are omnipresent in today's healthcare services and are employed in various applications, including implants, sensors, healthcare accessories, and drug delivery systems. Unfavorable host immunological responses frequently jeopardize the efficacy of biomaterials. As a result, surface modification has received much attention in controlling inflammatory responses since it helps camouflage the biomaterial from the host immune system, influencing the foreign body response (FBR) from protein adsorption to fibrous capsule formation. Surfaces with controlled nanotopography and chemistry, among other surface modification methodologies, have effectively altered the immune response to biomaterials. However, the field is still in its early stages, with only a few studies showing a synergistic effect of surface chemistry and nanotopography on inflammatory and wound healing pathways. Therefore, this review will concentrate on the individual and synergistic effects of surface chemistry and nanotopography on FBR modulation and the molecular processes known to modulate these responses. This review will also provide insights into crucial research gaps and advancements in various tactics for modulating FBR, opening new paths for future research. This will further aid in improving our understanding of the immune response to biomaterials, developing advanced surface modification techniques, designing immunomodulatory biomaterials, and translating discoveries into clinical applications.

Multi-material electrospinning: from methods to biomedical applications

Electrospinning as a versatile, simple, and cost-effective method to engineer a variety of micro or nanofibrous materials, has contributed to significant developments in the biomedical field. However, the traditional electrospinning of single material only can produce homogeneous fibrous assemblies with limited functional properties, which oftentimes fails to meet the ever-increasing requirements of biomedical applications. Thus, multi-material electrospinning referring to engineering two or more kinds of materials, has been recently developed to enable the fabrication of diversified complex fibrous structures with advanced performance for greatly promoting biomedical development. This review firstly gives an overview of multi-material electrospinning modalities, with a highlight on their features and accessibility for constructing different complex fibrous structures. A perspective of how multi-material electrospinning opens up new opportunities for specific biomedical applications, i.e., tissue engineering and drug delivery, is also offered.

Fabrication and Characterization of Polylactic Acid Electrospun Wound Dressing Modified with Polyethylene Glycol, Rosmarinic Acid and Graphite Oxide

Polylactic acid (PLA) is a biodegradable polymer made from natural sources, and its electrospinning (e-spinning) nanofiber membrane doped with antibacterial ingredients is widely used in the field of medical dressings. In this research, 9 wt% of rosmarinic acid (RosA) and 0.04 wt% of graphite oxide (GO) with synergistic antibacterial activity were introduced into the e-spinning PLA precursor solution, and the obtained PLA nanofiber membrane showed good antibacterial properties and wound healing effects. At the same time, a nonionic amphiphilic polymer, polyethylene glycol (PEG), was also introduced into this system to improve the hydrophilicity of the e-spinning membrane for wound healing application. The morphological characterization showed the RosA/GO and PEG did not affect the e-spinning of PLA. The tests of mechanical performance and wettability demonstrated that PEG and RosA/GO incorporated in PLA have migrated easily to the surface of the fiber. The e-spun PLA/PEG/RosA/GO membrane showed good antibacterial activity and promoted initial wound healing quickly, which would be a promising application in wound dressing.

Tannic acid-functionalized 3D porous nanofiber sponge for antibiotic-free wound healing with enhanced hemostasis, antibacterial, and antioxidant properties

Developing an antibiotic-free wound dressing with effective hemostasis and antibacterial and antioxidant capacity is highly desirable. In this work, a three-dimensional (3D) chitosan/polyvinyl alcohol-tannic acid porous nanofiber sponge (3D-TA) was prepared via electrospinning. Compared with two-dimensional (2D) fiber membrane, the unique fluffy 3D-TA nanofiber sponge had high porosity, water absorption and retention ability, hemostatic capacity. Furthermore, the 3D sponge functionalized by tannic acid (TA) endow the sponge with high antibacterial and antioxidant capacity without loading antibiotics. In addition, 3D-TA composite sponges have shown highly biocompatibility against L929 cells. The in vivo experiment shows the 3D-TA is enable to accelerate wound healing. This newly 3D-TA sponges hold great potential as wound dressings for future clinical application.

Fabrication of hierarchical porous ethyl cellulose fibrous membrane by electro-centrifugal spinning for drug delivery systems with excellent integrated properties

Drug delivery systems (DDSs) based on micro-and nano- fibrous membrane have been developed for decades, in which great attention has been focused on achieving controlled drug release. However, the study on the integrated performance of these drug-loaded membranes in the use of in-vitro drug delivery dressing is lacking, as clinical medication also needs consideration from the perspectives of wound safety and patient convenience. Herein, a trilayered hierarchical porous ethyl cellulose (EC) fibrous membrane based DDS (EC-DDS) was developed by electro-centrifugal spinning. Significantly, the hierarchical porous structure of the EC-DDSs with high specific surface area (34.3 m²g^-1) and abundant long-regulative micro-and nano- channels demonstrated its merits in improving the hydrophobicity (long-term splash resistance (CA > 130°) and prolonging the drug release (the release time of ~80 % tetracycline hydrochloride (TCH) prolonged from 10 min to 24 h). Meanwhile, the trilayered EC-DDS also revealed excellent biocompatibility, antibacterial activity, air permeability, moisture permeability, water absorption capacity, mechanical strength, and flexibility. With these excellent integrated features, the EC-DDS could prevent external fluids, avoid infection, and provide comfort. Furthermore, this work also provides a new guide for the high-efficiency fabrication of porous fibrous membranes.

Topically Applied Biopolymer-Based Tri-Layered Hierarchically Structured Nanofibrous Scaffold with a Self-Pumping Effect for Accelerated Full-Thickness Wound Healing in a Rat Model

Wound healing has grown to be a significant problem at a global scale. The lack of multifunctionality in most wound dressing-based biopolymers prevents them from meeting all clinical requirements. Therefore, a multifunctional biopolymer-based tri-layered hierarchically nanofibrous scaffold in wound dressing can contribute to skin regeneration. In this study, a multifunctional antibacterial biopolymer-based tri-layered hierarchically nanofibrous scaffold comprising three layers was constructed. The bottom and the top layers contain hydrophilic silk fibroin (SF) and fish skin collagen (COL), respectively, for accelerated healing, interspersed with a middle layer of hydrophobic poly-3-hydroxybutyrate (PHB) containing amoxicillin (AMX) as an antibacterial drug. The advantageous physicochemical properties of the nanofibrous scaffold were estimated by SEM, FTIR, fluid uptake, contact angle, porosity, and mechanical properties. Moreover, the in vitro cytotoxicity and cell healing were assessed by MTT assay and the cell scratching method, respectively, and revealed excellent biocompatibility. The nanofibrous scaffold exhibited significant antimicrobial activity against multiple pathogenic bacteria. Furthermore, the in vivo wound healing and histological studies demonstrated complete wound healing in wounded rats on day 14, along with an increase in the expression level of the transforming growth factor-β1 (TGF-β1) and a decrease in the expression level of interleukin-6 (IL-6). The results revealed that the fabricated nanofibrous scaffold is a potent wound dressing scaffold, and significantly accelerates full-thickness wound healing in a rat model.

Electroactive nanofibrous membrane with temperature monitoring for wound healing

Developing functional dressings for promoting cellular activities and monitoring the healing progress is receiving increasingly widespread attention. In this study, Ag/Zn electrodes were deposited on the surface of a polylactic acid (PLA) nanofibrous membrane which can mimic the extracellular matrix. When wetted by wound exudate, the Ag/Zn electrodes could generate an electric stimulation (ES), promoting the migration of fibroblasts that heal wounds. Moreover, the Ag/Zn@PLA dressing showed excellent antibacterial activity against E. coli (95%) and S. aureus (97%). The study found that the electrostatic (ES) effect and the release of metal ions mainly contribute to the wound healing properties of Ag/Zn@PLA. In vivo mouse models demonstrated that Ag/Zn@PLA could promote wound healing by improving re-epithelialization, collagen deposition, and neovascularization. Additionally, the integrated sensor within the Ag/Zn@PLA dressing can monitor the wound site's temperature in real-time, providing timely information on wound inflammatory reactions. Overall, this work suggests that combining electroactive therapy and wound temperature monitoring may provide a new strategy for designing functional wound dressings.

Smart microneedle patches for wound healing and management

The number of patients with non-healing wounds is generally increasing globally, placing a huge social and economic burden on every country. The complexity of the wound-healing process remains a major health challenge despite the numerous studies that have been reported on conventional wound dressings. Therefore, a therapeutic system that combines diagnostic and therapeutic modalities is essential to monitor wound-related biomarkers and facilitate wound healing in real time. Microneedles, as a multifunctional platform, are promising for transdermal diagnostics and drug delivery. Their advantages are mainly reflected in painless transdermal drug delivery, good biocompatibility, and ease of self-administration. In this work, we review recent advances in the use of microneedle patches for wound healing and monitoring. The paper first provides a brief overview of the skin structure and the wound healing process, and then discusses the current state of research and prospects for the development of wound-related biomarkers and their real-time monitoring based on microneedle sensors. It summarizes the current state of research based on the unique design of microneedle patches, including biomimetic, conductive, and environmentally responsive, to achieve wound healing. It further summarizes the prospects for the application of different microneedle-based drug delivery modalities and drug delivery substances for wound healing, due to their superior transdermal drug delivery advantages. It concludes with challenges and expectations for the use of smart microneedle patches for wound healing and management.

Engineered Sandwich-Structured Composite Wound Dressings with Unidirectional Drainage and Anti-Adhesion Supporting Accelerated Wound Healing

Proper management of exudate is of great clinical value for reducing wound infection and promoting wound healing, thus various dressings have been studied to address this widespread medical challenge. Herein, a novel sandwich-structured composite wound dressing (SCWD), integrating of a superlyophobic (SLO) polydimethylsiloxane (PDMS) layer, a superlyophilic gauze layer, and a lyophobic PDMS layer is presented, with particular unidirectional droplet drainage and stable anti-adhesion capabilities, which realizes effective management of wound exudate and provides a favorable environment for wound healing. Thanks to the stable SLO property on the PDMS surface with hierarchical micro/nanostructures, the continuously accumulated wound exudate at the interface between dressing and wound surface is gradually deformed, eventually passing through SLO PDMS layer through milli-scale channels and being absorbed by gauze layer. Experimental results show that the application of SCWD can significantly reduce the occurrence of wound infection, avoid the tearing of wound tissues when replacing dressings, and accelerate wound healing by ≈20%. The combination of SCWD and lyophilized powders of stem cells supernatant (LPSCS) is verified to better accelerate the healing process. The proposed method offers great potential in clinical applications, particularly for acute trauma wound treatments.

Luminescent MOF-Based Nanofibers with Visual Monitoring and Antibacterial Properties for Diabetic Wound Healing

Diabetic wound healing remains as a serious challenge for medical circles that required continuous monitoring and effective management. Herein, the glucose oxidase/carbon dots@copper-metal-organic framework-based nanofibers (GOx/CDs@MOF NFs) were proposed as a multifunctional wound dressing, aiming to visually monitor wound pH and inhibit bacterial infection. In the diabetic wound microenvironment, the GOx/CDs@MOF NFs could convert endogenous glucose into hydroxyl radial (•OH) through the cascade catalytic reaction. In vivo and vitro experimental results confirmed that the GOx/CDs@MOF NFs could efficiently kill bacteria and promote wound healing. Additionally, CDs as a pH fluorescent indicator endowed GOx/CDs@MOF NFs with sensitive and reversible fluorescent sensing behavior to wound pH, and these visual images could also be captured by smartphones and transformed into RGB color mode (red, green, blue) values, allowing for onsite evaluation of the wound status. This multifunctional wound dressing provides a smart and effective solution for diabetic wound management and takes an immeasurable step toward the development of the next generation of digitally visualized wound dressings.

Biomimetic three-layer hierarchical scaffolds for efficient water management and cell recruitment

Taking inspiration from the structures of roots, stems and leaves of trees in nature, a biomimetic three-layered scaffold was designed for efficient water management and cell recruitment. Using polycaprolactone (PCL) and polyacrylonitrile (PAN) as raw materials, radially oriented nanofiber films and multistage adjustable nanofiber films were prepared through electrospinning technology as the base skin-friendly layer (roots) and middle unidirectional moisture conductive material (stems), the porous polyurethane foam was integrated as the outer moisturizing layer (leaves). Among which, radially oriented nanofiber films could promote the directional migration of fibroblasts and induce cell morphological changes. For the spatially hierarchically nanofiber films, the unidirectional transport of liquid was effectively realized. While the porous polyurethane foam membrane could absorb 9 times its weight in biofluid and retain moisture for up to 10 h. As a result, the biomimetic three-layered scaffolds with different structures can promote wound epithelization and drain biofluid while avoiding wound inflammation caused by excessive biofluid, which is expected to be applied in the field of skin wounds.

Curcumin Functionalized Electrospun Fibers with Efficient pH Real-Time Monitoring and Antibacterial and Anti-inflammatory Properties

Wound infection has threatened the health of humans, and developing novel dressings by integrating infection detection and wound treatment in biomaterials is urgently required in the medical industry. In this study, we report a facile strategy to develop curcumin functionalized poly(ε-caprolactone) and gelatin composite fibrous membranes with pH real-time monitoring and antibacterial and anti-inflammatory properties. The developed curcumin-functionalized composite fibers displayed highly sensitive and visible response to the variation of the pH value of a buffer solution in the range of 5.6-8.6. In addition, the resultant fibrous membrane showed obviously enhanced antibacterial efficiency against both E. coli and S. aureus and no obvious cytotoxicity to human dermal fibroblasts when the curcumin content was less than 5 wt %. More importantly, 3 wt % curcumin-functionalized composite membrane exhibited excellent anti-inflammatory activities, good antioxidant activity of ca. 82%, and significantly decreased expression levels of pro-inflammatory cytokines like TNF-α and IL-6 in vitro (p < 0.001). Furthermore, subcutaneous embedding experiments showed that the 3 wt % curcumin-functionalized membrane significantly promoted cell penetration, recruited less macrophages, and facilitated collage deposition. Therefore, the curcumin-functionalized composite fibers could be employed to fabricate multifunctional dressings for the future treatment of chronic wounds.

Icy core-shell composite nanofibers with cooling, antibacterial and healing properties for outdoor burns

Burns are usually difficult to treat because their susceptibe to bacterial infections. When burns is accompanied by hyperthermia, the heat accumulated on the skin will causes extensive tissue damage. Most dressings focus on the treatment process, while ignoring the first-aid treatment to remove hyperthermia. To make matters worse, when outdoors, it is hard to find clean water to wash and cool the burned area. A dressing which can simultaneously realize first-time cooling and repairing treatment of the burned area can shorten treatment time, and is especially beneficial for outdoor use. In this study, a handheld coaxial electrospinning device is developed for preparing platelet-rich plasma @Polycaprolactone-epsilon polylysine (PRP@PCL/ε-PL) core-shell nanofibers. The nanofibers can be synchronously transformed into ice fibers during the spinning process, and directly deposited on the skin. The whole process is convenient to use outdoor. Via dual cooling mechanisms, first aid can take away the excessive heat in the burn area by nanofibers. These core-shell nanofibers also show its excellent antimicrobial and tissue regeneration-promoting properties. Therefore, it achieves first-time cooling and repair treatment of the burned area at the same time. Moreover, due to direct in-situ deposition of this handheld coaxial electrospinning, better antimicrobial properties, and faster healing performance are achieved. By using this integrated strategy that combines cooling, antibacterial and healing promotion, the burn recovery time is shortened from 21 days to 14 days.

Electrospun nanofibrous membrane with antibacterial and antiviral properties decorated with Myoporum bontioides extract and silver-doped carbon nitride nanoparticles for medical masks application

Public health safety issues have been plaguing the world since the pandemic outbreak of coronavirus disease (COVID-19). However, most personal protective equipments (PPE) do not have antibacterial and anti- toxicity effects. In this work, we designed and prepared a reusable, antibacterial and anti-toxicity Polyacrylonitrile (PAN) based nanofibrous membrane cooperated with Ag/g-C₃N₄ (Ag-CN), Myoporum.bontioides (M. bontioides) plant extracts and Ag nanoparticles (NPs) by an electrospinning-process. The SEM and TEM characterization revealed the formation of raised, creased or wrinkled areas on the fiber surface caused by the Ag nanoparticles, the rough surface prevented the aerosol particles on the fiber surface from sliding and stagnating, thus providing excellent filtration performance. The PAN/M. bontioides/Ag-CN/Ag nanofibrous membrane could be employed as a photocatalytic bactericidal material, which not only degraded 96.37% of methylene blue within 150 min, but also exhibited the superior bactericidal effect of 98.65 ± 1.49% and 97.8 ± 1.27% against E. coli and S. aureus, respectively, under 3 hs of light exposure. After 3 cycles of sterilization experiments, the PAN/M. bontioides/Ag-CN/Ag nanofibrous membrane maintained an efficient sterilization effect. Molecular docking revealed that the compounds in M. bontioides extracts interacted with neo-coronavirus targets mainly on Mpro and RdRp proteins, and these compounds had the strongest docking energy with Mpro protein, the shortest docking radius, and more binding sites for key amino acids around the viral protein targets, which influenced the replication and transcription process of neo-coronavirus. The PAN/M.bontioides/Ag-CN/Ag nanofibrous membrane also performed significant inhibition of influenza A virus H3N2. The novel nanofiber membrane is expected to be applied to medical masks, which will improve human isolation and protection against viruses.

Polysaccharide Electrospun Nanofibers for Wound Healing Applications

As a type of biological macromolecule, natural polysaccharides have been widely used in wound healing due to their low toxicity, good biocompatibility, degradability and reproducibility. Electrospinning is a versatile and simple technique for producing continuous nanoscale fibers from a variety of natural and synthetic polymers. The application of electrospun nanofibers as wound dressings has made great progress and they are considered one of the most effective wound dressings. This paper reviews the preparation of polysaccharide nanofibers by electrospinning and their application prospects in the field of wound healing. A variety of polysaccharide nanofibers, including chitosan, starch, alginate, and hyaluronic acid are introduced. The preparation strategy of polysaccharide electrospun nanofibers and their functions in promoting wound healing are summarized. In addition, the future prospects and challenges for the preparation of polysaccharide nanofibers by electrospinning are also discussed.

A Trilayer Dressing with Self-Pumping and pH Monitoring Properties for Promoting Abdominal Wall Defect Repair

Due to abdominal infection, excessive wound exudation, and intestinal fistula formation, the treatment of full-thickness abdominal wall defects has become a difficult challenge for clinic doctors. This clinical problem cannot be resolved with existing biomaterials. To facilitate the repair of the abdominal wall, we developed a novel wound dressing with directional biofluid transport. We used electrospinning to spin a trilayer dressing consisting of hydrolyzed poly-acrylonitrile (HPAN)/Curcumin (CUR), polyurethane (PU), and polycaprolactone (PCL). In vitro results show that the three-layer wound dressing is biocompatible, capable of directional transport of excessive wound exudation, preventing reverse penetration, and monitoring the pH of the wound. Furthermore, in vivo results show the trilayer wound dressing improves the wound microenvironment, reduces inflammatory factors, promotes angiogenesis, and accelerates abdominal wall repair. Thus, we believe that the novel trilayer electrospinning dressing could facilitate abdominal wall defect repair.

Recent Progress in Electrospun Polyacrylonitrile Nanofiber-Based Wound Dressing

Bleeding control plays a very important role in worldwide healthcare, which also promotes research and development of wound dressings. The wound healing process involves four stages of hemostasis, inflammation, proliferation and remodeling, which is a complex process, and wound dressings play a huge role in it. Electrospinning technology is simple to operate. Electrospun nanofibers have a high specific surface area, high porosity, high oxygen permeability, and excellent mechanical properties, which show great utilization value in the manufacture of wound dressings. As one of the most popular reactive and functional synthetic polymers, polyacrylonitrile (PAN) is frequently explored to create nanofibers for a wide variety of applications. In recent years, researchers have invested in the application of PAN nanofibers in wound dressings. Research on spun nanofibers is reviewed, and future development directions and prospects of electrospun PAN nanofibers for wound dressings are proposed.

A review on Biopolymer-derived Electrospun Nanofibers for Biomedical and Antiviral Applications

Unique aspects of polymer-derived nanofibers provide significant potential in the area of biomedical and health care applications. Much research has demonstrated several plausible nanofibers to overcome the modern-day challenges in...

Electrospun Nanofibers for Manipulating the Soft Tissue Regeneration

Soft tissue damage is a common clinical problem that affects the lives of a large number of patients all over the world. It is of great importance to develop functional...