Wound-dressing Materials Research Articles

Enhancement of antibacterial activity in electrospun fibrous membranes based on quaternized chitosan with caffeic acid and berberine chloride for wound dressing applications.

Electrospun nanofibers made from chitosan are promising materials for surgical wound dressings due to their non-toxicity and biocompatibility. However, the antibacterial activity of chitosan is limited by its poor water solubility under physiological conditions. This study addresses this issue by producing electrospun nanofibers mainly from natural compounds, including chitosan and quaternized chitosan, which enhance both its solubility for electrospinning and the antibacterial activity of the resulting electrospun nanofibers. Additionally, antimicrobial agents like caffeic acid or berberine chloride were incorporated. The glutaraldehyde-treated nanofibers showed improved mechanical properties, with an average tensile strength exceeding 2.7 MPa, comparable to other chitosan-based wound dressings. They also demonstrated enhanced water stability, retaining over 50% of their original weight after one week in phosphate-buffered saline (PBS) at 37 °C. The morphology and performance of these nanofibers were thoroughly examined and discussed. Furthermore, these membranes displayed rapid drug release, indicating potential for inhibiting bacterial growth. Antibacterial assays revealed that S2-CX nanofibers containing caffeic acid were most effective against E. coli and S. aureus, reducing their survival rates to nearly 0%. Similarly, berberine chloride-containing S4-BX nanofibers reduced the survival rates of E. coli and S. aureus to 19.82% and 0%, respectively. These findings suggest that electrospun membranes incorporating chitosan and caffeic acid hold significant potential for use in antibacterial wound dressings and drug delivery applications.

Fabrication, Characterization and Release Profile of Aloe Vera Extracts/PVA Composite Electrospun Nanofiber

Aloe vera is a well-known remedy that carries many beneficial health effects such as painkiller, anti-inflammatory, promote skin growth and repair. The combination of bioactive natural product of aloe vera as a drug model and polyvinyl alcohol (PVA) as the base material or carrier in the electrospinning process were studied. Smooth straight and continues electrospun fibers were collected with the Field Effect Scanning Electron Microscope (FESEM) images show no formation of bead (defect signed) in the electrospun membrane when the concentration was set at 10% w/w of PVA nanofibre. The morphological structure of the electrospun membranes shows a smooth and longitudinal fiber when aloe vera is mixed with the PVA polymer with percentage ratio of aloe vera over PVA is less than 25%. The Fourier Transform Infrared Spectroscopy (FTIR) shows no reaction between PVA and aloe vera by not showing peaks other than the initial materials. The Differential Scanning Calorimetry (DSC) proves the presence of aloin indicating the presence of aloe vera in nanofiber. The release profile of the electrospun aloe vera in PVA shows a higher initial burst release at the 50% and 70% concentration levels indicating very little control of the release or none at all. These results show the potential of aloe vera – PVA electrospun nanofibers membrane as a promising material for wound dressing and topical drug delivery.

Injectable Hydrogel With Glycyrrhizic Acid and Asiaticoside-Loaded Liposomes for Wound Healing.

Open skin wounds increase the risk of infections and can compromise health. Therefore, applying medications to promote healing at the injury site is crucial. In practice, direct drug delivery is often difficult to maintain for a long time due to rapid absorption or wiping off, which reduces the efficiency of wound healing. Consequently, the development of bioactive materials with both antibacterial and wound-healing properties is highly desirable. This study synthesized liposomes loaded with glycyrrhizic acid (GA) and asiaticoside (AS) by film dispersion-ultrasonication method, which were then incorporated into a GelMA solution and cross-linked by ultraviolet light to form a bioactive composite hydrogel for wound dressings. This hydrogel is conducive to the transport of nutrients and gas exchange. Compared with GelMA hydrogel (swelling rate 69.8% ± 5.7%), the swelling rate of GelMA/Lip@GA@AS is lower, at 52.1% ± 1.0%. GelMA/Lip@GA@AS also has better compression and rheological properties, and the invitro biodegradability is not significantly different from that of the collagenase-treated group. In addition, the hydrogel polymer has a stable drug release rate, good biocompatibility, and an angiogenic promoting effect. Invitro experiments prove that, at concentrations of 0.5, 1, 2, and 3 mg/mL, GelMA/Lip@GA@AS can inhibit the growth of Staphylococcus aureus. We synthesized GelMA/Lip@GA@AS hydrogel and found it possesses advantageous mechanical properties, rheology, and biodegradability. Experimental results invitro showed that the bioactive hydrogel could efficiently release drugs, exhibit biocompatibility, and enhance angiogenesis and antimicrobial effects. These results suggest the promising application of GelMA/Lip@GA@AS hydrogel in wound-dressing materials.

Advanced alginate-based nanofiber aerogels: A synthetic matrix for high-efficiency lysozyme adsorption and controlled release

The development of materials with high lysozyme adsorption is critical for drug delivery and skin wound applications, as it enhances antibacterial properties, stability, and controlled release of therapeutic agents, thereby improving treatment efficacy and safety. Alginate-based nanofiber scaffolds, featuring high surface area and multiple adsorption sites, can efficiently absorb lysozyme and regulate its release through tunable pore channels, offering a promising approach to chronic wound management. In this study, we fabricated poly (vinyl alcohol-co-ethylene) (EVOH) nanofiber-based sodium alginate (ENSA) aerogels using a simple two-step crosslinking procedure. The resulting aerogels, with controllable porosity formed via high-pressure spraying techniques (aerogel film) and molding (aerogel sponge), were evaluated for their high-loading capacity and controllable release of lysozyme. The aerogel film exhibited a remarkable lysozyme adsorption capacity of 1965 ± 36 mg/g, while the aerogel sponge sustained lysozyme release over 14 days. Analysis of the drug-release mechanism through four kinetic models revealed two distinct processes: cation exchange and matrix diffusion. The aerogel's pore structure influenced the diffusion processes, enabling tailored drug release profiles. Additionally, the ENSA aerogels demonstrated good mechanical properties, non-cytotoxicity, and potent antibacterial activity, positioning them as promising materials for skin wound dressings.

Injectable Salecan/hyaluronic acid-based hydrogels with antibacterial, rapid self-healing, pH-responsive and controllable drug release capability for infected wound repair

Designing materials for wound dressings with superior therapeutic benefits, self-healing and injectable characteristics is important in clinical practice. Herein, a new self-healing injectable hydrogel was prepared via thermal treatment and dynamic Schiff base reaction by mixing oxidized hyaluronic acid (OHA) and hydrazided Salecan (Sal-ADH). The versatility of the wound dressing was confirmed by studying the inherent rheological properties, high swelling rate, sustained-release behavior of the drug, pH/hyaluronidase-dependent biodegradation, in vitro antimicrobial as well as in vivo wound healing performance. The presence of the antimicrobial drug polyhexamethylene biguanide (PHMB) conferred good antimicrobial properties to the Sal-ADH/OHA/PHMB (SOP) hydrogel, which could effectively prevent wound infection (the width of the inhibition circle of SOP-0.20 hydrogel was 4.97 mm, 5.93 mm for Staphylococcus aureus and Escherichia coli, respectively). The findings suggested that SOP hydrogel exhibited remarkable self-healing and injectability properties, as well as excellent hemostasis and biocompatibility. In vivo experiments indicated that the application of SOP hydrogels would obviously accelerate wound healing and attenuate the inflammatory response while increasing collagen deposition and angiogenesis. Altogether, antibacterial SOP hydrogels with moderate mechanical properties, pH-responsive release, excellent injectability, exceptional self-healing ability and anti-inflammatory effects could expand potential applications of injectable hydrogels in the biomedical field.

Fabrication and development of biogenic selenium nanoparticles incorporated alginate hydrogel wound care material: a pre-clinical study

ABSTRACT In this study, we attempted to make a nanocomposite wound dressing that was both interactive and bioactive. In order to characterize the biogenic selenium nanoparticles, characterization techniques such as SEM, EDX, DLS, Zetasizer, FTIR, and XRD were utilized. The XRD results showed that the peaks located at around 2θ = 23.9°, 30.1°, 41.6°, 44.1°, and 52.9° that are corresponded to the (100), (101), (110), (102), and (201) reflections of the pure hexagonal phase of selenium crystals. The results of zeta potential measurement showed that the biosynthesized SeNPs have a zeta potential of around −27.5 mV. Studies conducted on animals using a full-thickness wound model of the rat’s skin showed that the wound dressing was able to speed up the natural process of wound healing. Based on the findings, it was determined that the wound dressing has the potential to serve as an effective wound dressing and healing material.

Fabrication of MIL-101(Fe)-embedded biopolymeric films and their biomedical applications

AbstractThe development of wound-dressing materials with superior therapeutic effects, controlled bioactive agent release, and optimal mechanical properties is crucial in healthcare. This study introduces innovative hydrogel films designed for the sustained release of the local anesthetic drug Procaine (PC), triggered by pH changes. These films are composed of MIL-101(Fe) particles and pectin polymers. MIL-101(Fe) was chosen for its high surface area, stability in aqueous environments, and biocompatibility, ensuring low toxicity to normal cells. MIL-101(Fe)-embedded-pectin hydrogels were synthesized and characterized using Fourier-transformed infrared (FTIR) spectroscopy, thermal gravimetric analysis (TGA), scanning electron microscopy (SEM), X-ray diffraction (XRD), inductively coupled plasma (ICP) spectrometry, particle size analysis, and goniometry. Rheological analysis assessed the hydrogels’ viscoelastic behavior, and UV-spectrophotometry was utilized for drug loading and release studies. The hydrogels exhibited shear-thinning properties, enhancing shape adaptability and recovery, crucial for wound-dressing applications. Controlled drug release was achieved by maintaining the PC solution’s pH between 8.2 and 9.8 during the drug-loading step. The hydrogel film’s impact on wound healing was evaluated through an in vitro wound healing assay, and cytotoxicity was assessed using a WST-1 cell proliferation assay with human dermal fibroblast cells. Results demonstrated that pectin composites enhance cell viability and support fibroblast cell migration without adverse effects, indicating their potential for effective wound healing applications. This study highlights the potential of MIL-101(Fe)-embedded-pectin hydrogels in advancing wound care technology. Graphical Abstract MIL-101(Fe)-embedded pectin film as wound dressing

Barnacle-inspired and polyphenol-assisted modification of bacterial cellulose-based wound dressings for promoting infectious wound healing

Bacterial cellulose (BC) is an ideal candidate for wound dressings due to its natural origin, exceptional water-holding capacity, pliability, biocompatibility, and high absorption capability. However, the lack of essential antimicrobial activity limits its biomedical applications. This study reported BC-based wound dressings containing silk fibroin protein (SF), offering the potential for biomimetic properties, and (−)-epigallocatechin-3-gallate (EGCG) for polyphenol-assisted surface modification to promote infectious wound healing. Glycerol was used as the carbon source to promote the formation of an adhesive layer by facilitating the β-sheet folding of SF, and different concentrations of EGCG were employed to interact with SF through strong hydrogen bonding facilitated by the polyphenolic groups. The functionalized membrane exhibited outstanding water-holding capacity, swelling ratio, and degradation properties, along with enhanced hydrophilicity, adhesiveness, and a remarkable free radical scavenging ability. Both in vitro and in vivo experiments confirmed its potent bacteriostatic activity. The composite membrane displayed excellent biocompatibility, including cellular and hemocompatibility. Importantly, it effectively promoted wound healing in murine back infections. These findings suggest the significant feasibility of the innovative modification approach, and that functionalized membranes have great potential as wound-dressing materials for infection management in future clinical applications.

Physical, antibacterial, blood coagulation, and healing promotion evaluations of chitosan derivative-based composite films

Chitosan is a potentially suitable material for wound dressing, but is undesirably water-insoluble. Although chitosan can be modified to produce water-soluble derivatives, the best chitosan derivative for wound dressings remains unclear. The present study introduced three water-soluble chitosan derivatives, namely, carboxymethyl chitosan, quaternized chitosan (QCS), and carboxymethyl quaternized chitosan, and explored the physical properties, biochemical properties, and wound care effectiveness of films of these derivatives. The QCS-based film exhibited higher absorption ability, mechanical properties, water-vapor permeability, electroconductivity, and antioxidant capacity than the other films. Most importantly, the cationic quaternary ammonium groups facilitated the antibacterial activity (>95 %) and blood coagulant capacity of the QCS-based film. As this film also promoted wound healing, it presented as an ideal candidate for wound dressings.

Electrospun Gelatin Scaffolds with Incorporated Antibiotics for Skin Wound Healing.

Recent advances in regenerative medicine provide encouraging strategies to produce artificial skin substitutes. Gelatin scaffolds are successfully used as wound-dressing materials due to their superior properties, such as biocompatibility and the ability to mimic the extracellular matrix of the surrounding environment. In this study, five gelatin combination solutions were prepared and successfully electrospun using an electrospinning technique. After careful screening, the optimal concentration of the most promising combination was selected for further investigation. The obtained scaffolds were crosslinked with 25% glutaraldehyde vapor and characterized by scanning electron microscopy, energy-dispersive X-ray spectroscopy, and Fourier-transform infrared spectroscopy. The incorporation of antibiotic agents such as ciprofloxacin hydrochloride and gentamicin sulfate into gelatin membranes improved the already existing antibacterial properties of antibiotic-free gelatin scaffolds against Pseudomonas aeruginosa and Staphylococcus aureus. Also, the outcomes from the in vivo model study revealed that skin regeneration was significantly accelerated with gelatin/ciprofloxacin scaffold treatment. Moreover, the gelatin nanofibers were found to strongly promote the neoangiogenic process in the in vivo chick embryo chorioallantoic membrane assay. Finally, the combination of gelatin's extracellular matrix and antibacterial agents in the scaffold suggests its potential for effective wound-healing treatments, emphasizing the importance of gelatin scaffolds in tissue engineering.

In situ alkali‐free growth of octahedral Ag2O nanoparticles by bacterial cellulose for efficient antibacterial application

AbstractUniform octahedral Ag2O nanoparticles were in situ synthesized within natural bacterial cellulose (BC) films without any inorganic alkali. The morphological transformation of Ag2O from nanoparticles and small nanoplates to an octahedral structure was well controlled by varying the UV exposure time. To reduce and anchor Ag2O nanoparticles, abundant hydroxyl groups on the surface of natural BC fibers ensured an ideal environment for the mild redox reaction between Ag+ and –OH groups. The structural features and structure–activity relationship of Ag2O/BC films were confirmed through TEM, energy dispersive spectroscopy assisted SEM analysis, Fourier transform IR, X‐ray photoelectron spectroscopy, TGA and XRD. The structure–antibacterial activity relationship of the Ag2O/BC films was proved against both Gram‐positive (Staphylococcus aureus) and Gram‐negative (Escherichia coli) bacteria. They also showed excellent performance in the photocatalytic degradation of organic dyes. Ag2O/BC films have potential bactericidal applications in the field of pharmacy, specifically for wound dressing and flexible wearable materials. © 2024 Society of Chemical Industry.

Stimulated Full-Thickness Cutaneous Wound Healing with Bioactive Dressings of Zinc and Cobalt Ion-Doped Bioactive Glass-Coated Eggshell Membranes in a Diabetic Rabbit Model.

Eggshell membrane-based biomedical applications have recently received great attention for their wound-healing properties. However, there are limited studies on diabetic wound healing. In this regard, we devised four types of composite eggshell membrane mats with nanoscale coatings of bioactive glass/Zn/Co-doped bioactive glass (ESM + BAG, ESM + ZnBAG, ESM + CoBAG, and ESM + ZnCoBAG) as wound-dressing materials for chronic nonhealing diabetic wounds. A detailed study of the physicochemical properties of the mats was conducted. In vitro studies demonstrated cytocompatibility and viability of human dermal fibroblasts on all four types of mats. The cells also attached finely on the mats with the help of cellular extensions, as evident from scanning electron microscopy (SEM) and rhodamine-phalloidin and Hoechst 33342 staining of cellular components. Endowed with bioactive properties, these mats influenced all aspects of full-thickness skin wound healing in diabetic animal model studies. All of the mats, especially the ESM + ZnCoBAG mat, showed the earliest wound closure, effective renewal, and restructuring of the extracellular matrix in terms of an accurate and timely accumulation of collagen, elastin, and reticulin fibers. Hydroxyproline and sulfated glycosaminoglycans were significantly (p < 0.01, p < 0.05) higher in ESM-ZnCoBAG-treated wounds in comparison to ESM-BAG-treated wounds, which suggests that these newly developed mats have potential as an affordable diabetic wound care solution in biomedical research.

Enrichment of creatine-gelatin cryogel with Zataria multiflora essential oil and titanium dioxide nanoparticles as a potential wound dressing

The prevalence of microbial infections in wounds, particularly burn wounds, presents a significant medical concern due to the inherent vulnerability of compromised skin to pathogen colonization and invasion. This study focused on the synthesis and evaluation of a creatine-gelatin cryogel, enriched with Zataria multiflora essential oil and titanium dioxide nanoparticles for potential wound dressing applications. The chemical and physical characteristics of the formulation were characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscopy, and mechanical tests. Further studies such as wound fluid absorptivity, water vapor transmission rate, solubility, moisture content, porosity, and release properties were investigated. The release test demonstrated an encapsulation efficiency of 98.8 % and a loading capacity of 16.45 %, signifying a suitable cryogel matrix. The disk diffusion assay demonstrated that the synthesized cryogel had excellent antimicrobial efficacy against Staphylococcus aureus, Pseudomonas aeruginosa, Escherichia coli, and Candida species. Additionally, the cryogel exhibited great cytocompatibility and hemocompatibility (∼100 %). Our findings suggest that the creatine-gelatin cryogel blend enriched with Zataria multiflora essential oil and titanium dioxide nanoparticles possesses structural integrity, a cell-friendly nature, moisture-retaining capabilities, and biocompatible characteristics. These properties collectively render it an exceptionally suitable material for advanced wound dressings. Moreover, the demonstrated functional properties of the cryogel, including its ability to prevent infection, exhibit antioxidant activity, and retain moisture, underscore its potential for effective burn wound management.

Designing of tragacanth gum-poly(2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide) and poly(acrylamide) based hydrogels for drug delivery and wound dressing applications

Bioactive tragacanth gum (TG) was functionalized by covalent crosslinking of poly[2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (PMEDSAH) to design network structure in form of hydrogel wound dressings (HWD). These copolymers were encapsulated with antibiotic drug vancomycin to enhance wound healing potential of the dressings. The copolymers were characterized by SEM, AFM, FTIR, 13C NMR, XRD, and TGA-DSC analysis. SEM demonstrated uneven heterogeneous morphology and AFM revealed rough surface of copolymer. Inclusion of synthetic component into HD was confirmed by FTIR and 13C NMR. Hydrogel dressings absorbed 8.49 ​± ​1.03 ​g/g simulated wound fluid and exhibited non-hemolytic (3.7 ​± ​0.02 % hemolytic potential) and antioxidant (37.42 ​± ​1.54 ​% free radical scavenging in DPPH assay) properties. Polymers required 35.0 ​± ​5.0 ​mN detachment force to get it detach from the mucosal surface during mucoadhesive test. Tensile strength was found to be 1.88 ​± ​0.13 ​N/mm2 during mechanical stability test. Hydrogel dressings were permeable to O2/H2O and impermeable to microbes. Release of drug vancomycin occurred through non-Fickian diffusion mechanism and release profile was best described by Korsmeyer-Peppas kinetic model. Overall, these results revealed that these hydrogels could be explored as materials for hydrogel wound dressings.

MOFs and MOF-Based Composites as Next-Generation Materials for Wound Healing and Dressings.

In recent years, there has been growing interest in developing innovative materials and therapeutic strategies to enhance wound healing outcomes, especially for chronic wounds and antimicrobial resistance. Metal-organic frameworks (MOFs) represent a promising class of materials for next-generation wound healing and dressings. Their high surface area, pore structures, stimuli-responsiveness, antibacterial properties, biocompatibility, and potential for combination therapies make them suitable for complex wound care challenges. MOF-based composites promote cell proliferation, angiogenesis, and matrix synthesis, acting as carriers for bioactive molecules and promoting tissue regeneration. They also have stimuli-responsivity, enabling photothermal therapies for skin cancer and infections. Herein, a critical analysis of the current state of research on MOFs and MOF-based composites for wound healing and dressings is provided, offering valuable insights into the potential applications, challenges, and future directions in this field. This literature review has targeted the multifunctionality nature of MOFs in wound-disease therapy and healing from different aspects and discussed the most recent advancements made in the field. In this context, the potential reader will find how the MOFs contributed to this field to yield more effective, functional, and innovative dressings and how they lead to the next generation of biomaterials for skin therapy and regeneration.

A new candidate for wound dressing materials: s-IPN hydrogel-based highly elastic and pH-sensitive drug delivery system containing pectin and vinyl phosphonic acid

In this study, we developed pH-sensitive semi-interpenetrating network (s-IPN) hydrogels, composed of pectin, 2-hydroxyethyl methacrylate (HEMA), and vinyl phosphonic acid (VPA) using N,N'-methylene bis(acrylamide) (MBA) as a cross-linker with the free-radical polymerization method. The formation of s-IPNs was confirmed by FTIR studies. SEM images showed the addition of VPA to the polymeric matrix of s-IPN hydrogels formed additional microporous structures within the hydrogel network. The s-IPN hydrogel had perfect mechanical features like stretchability, compressibility and elasticity. Additionally, the swelling behavior of s-IPN hydrogels in deionized water and solutions with diverse pH was assessed. To research use as a controlled drug delivery material, the hydrogel was loaded with cimetidine and trimethoprim. At pH 7.2, the in vitro drug release profile was observed and nearly 60 % of the drugs were released from s-IPN hydrogel within 10 h. Additionally, the most appropriate kinetic release model was Higuchi, followed by Korsmeyer-Peppas. Finally, silver sulfadiazine (SSD) was added to s-IPN hydrogel for use as a smart wound dressing material. Antimicrobial analysis of the SSD-loaded s-IPN hydrogel found it had antimicrobial features, inducing 15, 17 and 23 mm inhibition zones against Staphylococcus aureus (gram-positive), Escherichia coli (gram-negative) and Candida albicans (fungus) microorganisms, respectively. In light of the obtained results, based on being easily shapable with appropriate mechanical and physical features, pectin/p(HEMA-co-VPA) and pectin/p(HEMA-co-VPA)@SSD s-IPN hydrogels are potential candidates for use as controlled drug delivery and wound dressing materials in the biomedical field.

Polycaprolactone Nanofibers Functionalized by Fibronectin/Gentamicin and Implanted Silver for Enhanced Antibacterial Properties, Cell Adhesion, and Proliferation.

Novel nanomaterials used for wound healing should have many beneficial properties, including high biological and antibacterial activity. Immobilization of proteins can stimulate cell migration and viability, and implanted Ag ions provide an antimicrobial effect. However, the ion implantation method, often used to introduce a bactericidal element into the surface, can lead to the degradation of vital proteins. To analyze the surface structure of nanofibers coated with a layer of plasma COOH polymer, fibronectin/gentamicin, and implanted with Ag ions, a new X-ray photoelectron spectroscopy (XPS) fitting method is used for the first time, allowing for a quantitative assessment of surface biomolecules. The results demonstrated noticeable changes in the composition of fibronectin- and gentamicin-modified nanofibers upon the introduction of Ag ions. Approximately 60% of the surface chemistry has changed, mainly due to an increase in hydrocarbon content and the introduction of up to 0.3 at.% Ag. Despite the significant degradation of fibronectin molecules, the biological activity of Ag-implanted nanofibers remained high, which is explained by the positive effect of Ag ions inducing the generation of reactive oxygen species. The PCL nanofibers with immobilized gentamicin and implanted silver ions exhibited very significant antipathogen activity to a wide range of Gram-positive and Gram-negative strains. Thus, the results of this work not only make a significant contribution to the development of new hybrid fiber materials for wound dressings but also demonstrate the capabilities of a new XPS fitting methodology for quantitative analysis of surface-related proteins and antibiotics.

Advances in stimuli-responsive injectable hydrogels for biomedical applications.

Injectable hydrogels, as a class of highly hydrated soft materials, are of interest for biomedicine due to their precise implantation and minimally invasive local drug delivery at the implantation site. The combination of in situ gelation ability and versatile therapeutic agent/cell loading capabilities makes injectable hydrogels ideal materials for drug delivery, tissue engineering, wound dressing and tumor treatment. In particular, the stimuli-responsive injectable hydrogels that can respond to different stimuli in and out of the body (e.g., temperature, pH, redox conditions, light, magnetic fields, etc.) have significant advantages in biomedicine. Here, we summarize the design strategies, advantages, and recent developments of stimuli-responsive injectable hydrogels in different biomedical fields. Challenges and future perspectives of stimuli-responsive injectable hydrogels are also discussed and the future steps necessary to fulfill the potential of these promising materials are highlighted.

α-Terpineol loaded, electron beam crosslinked polyvinyl alcohol/tapioca starch hydrogel sheets; fabrication, characterization and evaluation of wound healing potential on a full thickness acid burn wound.

The multifaceted challenges in treating full-thickness acid burn wounds including impaired tissue regeneration, increased risk of infection, and the pursuit of functional and aesthetically pleasing outcomes, highlights the need for innovative therapeutic approaches for their treatment. The exceptional biochemical and mechanical properties of hydrogels, particularly their extracellular matrix-like nature and their potential to incorporate functional ingredients positions them as promising materials for wound dressings, offering a potential solution to the complexities of full-thickness burn wound management. The current study has integrated functional ingredients (starch and α-terpineol), known for their angiogenic, fibroblast-adhesive, and anti-inflammatory properties into an α-terpineol loaded, electron beam crosslinked polyvinyl alcohol/tapioca pearl starch hydrogel. The hydrogel was then explored for its efficacy in treating full-thickness acid burns. The hydrogel sheets, fabricated using a 25 kGy electron beam, were characterized for structural and functional properties. Surface morphology, gel fraction, swelling ratio, moisture retention capacity and thermal stability were also evaluated. PVA/tapioca starch hydrogel demonstrated optimal macroporosity, mechanical strength, thermal stability, water retention, and moisturizing ability, making it ideal for the intended application. In vitro skin compatibility analysis of α-terpineol-loaded hydrogel confirmed its biocompatibility, demonstrating 90% fibroblast viability. In vivo sensitivity testing on normal rat skin showed no inflammatory response. Analysis of the full-thickness rat chemical burn wounds treated with the hydrogels demonstrated that α-terpineol (AT) loaded e-beam crosslinked PVA/tapioca starch hydrogels increased the rate of wound closure, promoted re-epithelialization, facilitated collagen deposition, stimulated angiogenesis, and promoted keratin deposition, ultimately leading to healing of both thick dermal and epidermal tissues, as well as partial restoration of skin appendages over a duration of 30 days as confirmed by the histological and immunohistochemistry staining. Collectively, this study indicates that α-terpineol (AT) loaded e-beam crosslinked PVA/tapioca starch hydrogel holds promise as a cost-effective and efficient wound dressing for expediting full thickness acid burn wound healing, thus expanding the practical applications of the natural polymer based sheet hydrogel dressings.

Automatic in situ short-distance deposition of PLGA/PLLA composite nanofibrous membranes for personalized wound dressings.

Improving the mechanical properties of wound dressings and achieving personalized automatic real-time in situ deposition are important for accelerating wound management and repair. In this study, we report a self-designed automatic in situ deposition device based on solution blow spinning (SBS) to prepare poly(lactic-co-glycolic acid) (PLGA) and poly-L-lactic acid (PLLA) composite (PLGA/PLLA) nanofibrous membranes for wound dressing at a short distance. Polymer solution and in situ deposition conditions, including air pressure, spinning distance, solvent extrusion rate, and spinning rate, were optimized using orthogonal experiments and characterized via dynamic mechanical analysis. The microscopic morphology and physical properties of the prepared PLGA/PLLA composite nanofibrous membranes show that their strength, adhesion, water vapor transmission rate (WVTR), water retention, water absorption, degradation, and other properties were sufficient for wound-dressing applications. To investigate the possibility of a biomedical wound-dressing material, tannic acid (TA) was incorporated into the PLGA/PLLA composite nanofibrous membranes. The resultant PLGA/PLLA/TA composite nanofibrous membranes exhibited good biocompatibility and exceptional antibacterial properties against both Escherichia coli and Staphylococcus aureus. A pilot animal study illustrated the potential of this in situ deposition of PLGA/PLLA/TA composite nanofibrous membranes across multiple applications in wound healing/repair by reducing wound scar tissue formation and fibroblast overactivation.