Polymeric hydrogels for burn wound care: Advanced skin wound dressings and regenerative templates

Advancing burn wound treatment: exploring hydrogel as a transdermal drug delivery system

Burn injuries are prevalent and life-threatening forms that contribute significantly to mortality rates due to associated wound infections. The management of burn wounds presents substantial challenges. Hydrogel exhibits tremendous potential as an ideal alternative to traditional wound dressings such as gauze. This is primarily attributed to its three-dimensional (3D) crosslinked polymer network, which possesses a high water content, fostering a moist environment that supports effective burn wound healing. Additionally, hydrogel facilitates the penetration of loaded therapeutic agents throughout the wound surface, combating burn wound pathogens through the hydration effect and thereby enhancing the healing process. However, the presence of eschar formation on burn wounds obstructs the passive diffusion of therapeutics, impairing the efficacy of hydrogel as a wound dressing, particularly in cases of severe burns involving deeper tissue damage. This review focuses on exploring the potential of hydrogel as a carrier for transdermal drug delivery in burn wound treatment. Furthermore, strategies aimed at enhancing the transdermal delivery of therapeutic agents from hydrogel to optimize burn wound healing are also discussed.

Nanofiber-reinforced self-healing polysaccharide-based hydrogel dressings for pH discoloration monitoring and treatment of infected wounds

The escalating global health concern arises from chronic wounds induced by bacterial infections, posing a significant threat to individuals. Consequently, an imperative exist for the development of hydrogel dressings to facilitate prompt wound monitoring and efficacious wound management. To this end, pH-sensitive bromothymol blue (BTB) and pH-responsive drug tetracycline hydrochloride (TH) were introduced into the polysaccharide-based hydrogel to realize the integration of wound monitoring and controlled treatment. Polysaccharide-based hydrogels were formed via a Schiff base reaction by cross-linking carboxymethyl chitosan (CMCS) on an oxidized sodium alginate (OSA) skeleton. BTB was used as a pH indicator to monitor wound infection through visual color changes visually. TH could be dynamically released through the pH response of the Schiff base bond to provide effective treatment and long-term antibacterial activity for chronically infected wounds. In addition, introducing polylactic acid nanofibers (PLA) enhanced the mechanical properties of hydrogels. The multifunctional hydrogel has excellent mechanical, self-healing, injectable, antibacterial properties and biocompatibility. Furthermore, the multifaceted hydrogel dressing under consideration exhibits noteworthy capabilities in fostering the healing process of chronically infected wounds. Consequently, the research contributes novel perspectives towards the advancement of intelligent and expeditious bacterial infection monitoring and dynamic treatment platforms.

Development and characterization of polyethylene oxide and guar gum-based hydrogel; a detailed in-vitro analysis of degradation and drug release kinetics

Herein, we synthesized hydrogel films from crosslinked polyethylene oxide (PEO) and guar gum (GG) which can offer hydrophilicity, antibacterial efficacy, and neovascularization. This study focuses on synthesis and material/biological characterization of rosemary (RM) and citric acid (CA) loaded PEO/GG hydrogel films. Scanning Electron Microscopy images confirmed the porous structure of the developed hydrogel film matrix (PEO/GG) and the dispersion of RM and CA within it. This porous structure promotes moisture adsorption, cell attachment, proliferation, and tissue layer formation. Fourier Transform Infrared Spectroscopy (FTIR) further validated the crosslinking of the PEO/GG matrix, as confirmed by the appearance of C-O-C linkage in the FTIR spectrum. PEO/GG and PEO/GG/RM/CA revealed similar degradation and release kinetics in Dulbecco's Modified Eagle Medium, Simulated Body Fluid, and Phosphate Buffer Saline (degradation of ∼55 % and release of ∼60 % RM in 168 h.). The developed hydrogel film exhibited a zone of inhibition against Escherichia. coli (2 mm) and Staphylococcus. aureus (9 mm), which can be attributed to the presence of RM in the hydrogel film. Furthermore, incorporating CA in the hydrogel film promoted neovascularization, as confirmed by the Chorioallantoic Membrane Assay. The developed RM and CA-loaded PEO/GG-based hydrogel films offered suitable in-vitro properties that may aid in potential wound healing applications.

Recent Advances in Smart Self-Assembled Bioinspired Hydrogels: A Bridging Weapon for Emerging Health Care Applications from Bench to Bedside

Stimuli-responsive low molecular weight hydrogel interventions for Biomedical challenges are a rapidly evolving paradigm in the bottom-up approach recently. Peptide-based self-assembled nano biomaterials present safer alternatives to their non-degradable counterparts as demanded for today's most urged clinical needs.Although a plethora of work has already been accomplished, programming hydrogelators with appropriate functionalities requires a better understanding as the impact of the macromolecular structure of the peptides and subsequently, their self-assembled nanostructures remain unidentified. Henceforth this review focuses on two aspects: Firstly, the underlying guidelines for building biomimetic strategies to tailor scaffolds leading to hydrogelation along with the role of non-covalent interactions that are the key components of various self-assembly processes. In the second section, it is aimed to bring together the recent achievements with designer assembly concerning their self-aggregation behaviour and applications mainly in the biomedical arena like drug delivery carrier design, antimicrobial, anti-inflammatory as well as wound healing materials. Furthermore, it is anticipated that this article will provide a conceptual demonstration of the different approaches taken towards the construction of these task-specific designer hydrogels. Finally, a collective effort among the material scientists is required to pave the path for the entrance of these intelligent materials into medicine from bench to bedside.

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.

Microneedle Patch for Transdermal Sequential Delivery of KGF-2 and aFGF to Enhance Burn Wound Therapy

Severe burn wounds usually destroy key cells' functions of the skin resulting in delayed re-epithelization and wound regeneration. Promoting key cells' activities is crucial for burn wound repair. It is well known that keratinocyte growth factor-2 (KGF-2) participates in the proliferation and morphogenesis of epithelial cells while acidic fibroblast growth factor (aFGF) is a key mediator for fibroblast and endothelial cell growth and differentiation. However, thick eschar and the harsh environment of a burn wound often decrease the delivery efficiency of fibroblast growth factor (FGF) to the wound site. Therefore, herein a novel microneedle patch for sequential transdermal delivery of KGF-2 and aFGF is fabricated to enhance burn wound therapy. aFGF is first loaded in the nanoparticle (NPaFGF) and then encapsulated NPaFGF with KGF-2 in the microneedle patch (KGF-2/NPaFGF@MN). The result shows that KGF-2/NPaFGF@MN can successfully get across the eschar and sequentially release KGF-2 and aFGF. Additional data demonstrated that KGF-2/NPaFGF@MN achieved a quicker wound closure rate with reduced necrotic tissues, faster re-epithelialization, enhanced collagen deposition, and increased neo-vascularization. Further evidence suggests that improved wound healing is regulated by significantly elevated expressions of hypoxia-inducible factor-1 alpha (HIF-1ɑ) and heat shock protein 90 (Hsp90) in burn wounds. All these data proved that KGF-2/NPaFGF@MN is an effective treatment for wound healing of burns.

Combination of a pH-responsive peptide amphiphile and a conventional antibiotic in treating Gram-negative bacteria

BACKGROUND

Clinical treatments ofgastric infections using antibiotics suffer from the undesired killing of commensal bacteria and emergence of antibiotic resistance. It is desirable to develop pH-responsive antimicrobial peptides (AMPs) that kill pathogenic bacteria such as H. pyloriand resistant E. coli under acidic environment with minimal impact to commensal bacteria whilst not causing antibiotic resistance.

EXPERIMENTS

Using a combined approach of cell assays, molecular dynamics (MD) simulations and membrane models facilitating biophysical and biochemical measurements including small angle neutron scattering (SANS), we have characterized the pH-responsive physiochemical properties and antimicrobial performance of two amphiphilic AMPs, GIIKDIIKDIIKDI-NH2 and GIIKKIIDDIIKKI-NH2 (denoted as 3D and 2D, respectively), that were designed by selective substitutions of cationic residues of Lys (K) in the extensively studied AMP G(IIKK)3I-NH2 with anionic residue Asp (D).

FINDINGS

Whilst 2D kept non-ordered coils across the entire pH range studied, 3D displayed a range of secondary structures when pH was shifted from basic to acidic, with distinct self-assembly into nanofibers in aqueous environment. Further experimental and modeling studies revealed that the AMPs interacted differently with the inner and outer membranes of Gram-negative bacteria in a pH-responsive manner and that the structural features characterized by membrane leakage and intramembrane nanoaggregates revealed from fluorescence spectroscopy and SANS were well linked to antimicrobial actions. Different antimicrobial efficacies of 2D and 3D were underlined by the interplay between their ability to bind to the outer membrane lipid LPS (lipopolysaccharide), outer membrane permeability change and inner membrane depolarization and leakage. Furthermore, AMP's binding with the inner membrane under acidic condition caused both the dissipation of membrane potential (Δψ) and the continuous dissipation of transmembrane ΔpH, with Δψ and ΔpH being the key components of the proton motive force. Combinations of antibiotic (Minocycline) with the pH-responsive AMP generated the synergistic effects against Gram-negative bacteria only under acidic condition. These features are crucial to target applications to gastric infections, anti-acne and wound healing.

Glycosaminoglycans' Ability to Promote Wound Healing: From Native Living Macromolecules to Artificial Biomaterials

Glycosaminoglycans (GAGs) are important for the occurrence of signaling molecules and maintenance of microenvironment within the extracellular matrix (ECM) in living tissues. GAGs and GAG-based biomaterial approaches have been widely explored to promote in situ tissue regeneration and repair by regulating the wound microenvironment, accelerating re-epithelialization, and controlling ECM remodeling. However, most approaches remain unacceptable for clinical applications. To improve insights into material design and clinical translational applications, this review highlights the innate roles and bioactive mechanisms of native GAGs during in situ wound healing and presents common GAG-based biomaterials and the adaptability of application scenarios in facilitating wound healing. Furthermore, challenges before the widespread commercialization of GAG-based biomaterials are shared, to ensure that future designed and constructed GAG-based artificial biomaterials are more likely to recapitulate the unique and tissue-specific profile of native GAG expression in human tissues. This review provides a more explicit and clear selection guide for researchers designing biomimetic materials, which will resemble or exceed their natural counterparts in certain functions, thereby suiting for specific environments or therapeutic goals.

Current Advances in Wound Healing and Regenerative Medicine

Treating chronic wounds is a common and costly challenge worldwide. More advanced treatments are needed to improve wound healing and prevent severe complications such as infection and amputation. Like other medical fields, there have been advances in new technologies promoting wound healing potential. Regenerative medicine as a new method has aroused hope in treating chronic wounds. The technology improving wound healing includes using customizable matrices based on synthetic and natural polymers, different types of autologous and allogeneic cells at different differentiation phases, small molecules, peptides, and proteins as a growth factor, RNA interference, and gene therapy. In the last decade, various types of wound dressings have been designed. Emerging dressings include a variety of interactive/ bioactive dressings and tissue-engineering skin options. However, there is still no suitable and effective dressing to treat all chronic wounds. This article reviews different wounds and common treatments, advanced technologies and wound dressings, the advanced wound care market, and some interactive/bioactive wound dressings in the market.

β-Carotene laden antibacterial and antioxidant gelatin/polyglyceryl stearate nano-hydrogel system for burn wound healing application

Worldwide, burn wounds are severe health issues prone to bacterial infections and challenging to treat with traditional wound dressings. Therefore, a highly desirable biological macromolecules-based wound dressing with good antioxidant, antibacterial, biocompatible, and a large surface area is required. Herein, aim to develop a biological macromolecules-based physically cross-linked gelatin/polyglyceryl stearate/graphene oxide (GPGO) hydrogel to treat burn wounds. Four sets of hydrogels were prepared by varying GO concentrations. FT-IR, FE-SEM, viscosity analysis, mechanical and thermal stability confirmed the successful preparation of hydrogels with desired properties. Further, β-carotene (0.5 mg/mL) was encapsulated in hydrogels to enhance the antioxidant activity, and a cumulative release as well as kinetics at pH 6.4 and 7.4 was performed. With an increase in GO concentration, hydrogels showed sustained release of β-carotene. Among all, GPGO-3 β hydrogel showed the highest antioxidant potency (57.75 %), hemocompatible (<5 %), cytocompatible (viable with NIH 3T3 cells), cell migration, proliferation, and in vitro wound healing. Also, GPGO-3 β hydrogel showed efficient antibacterial activity (%inhibition of 85.5 % and 80.2 % and zone of 11 mm and 9.8 mm against S. aureus and E. coli). These results demonstrated the ability of GPGO-3 β hydrogel as a promising candidate for burn wound healing applications.

Preparation and characterization of wound healing hydrogel based on fish skin collagen and chitosan cross-linked by dialdehyde starch

Hydrogels due to high water absorption capacity, flexibility, biodegradability properties and also the ability to provide a moist environment, same as native extracellular, are widely used for wound healing applications. Developing multifunctional hydrogels using biomaterial is an emerging approach in this area. Collagen and chitosan are known as excellent biomaterials due to their properties, functionality, and sustainable sources. They also have good biocompatibility and biodegradability, suitable for wound healing hydrogels. In this study, the physicochemical characterization, morphology, and biocompatibility of collagen/chitosan/ dialdehyde starch hydrogel (Col/Ch/DAS) were evaluated. Type I collagen was extracted from silver carp skin by-product. DAS was synthesized by a one-step method of acid hydrolysis and oxidation. Hydrogels were made from collagen (4 % w/v) and chitosan mix (2 % w/v) and added DAS (2 % w/v) (0.5, 1.0 and 1.5 ml) as a cross-linker to enhance the physicochemical behaviors of the hydrogels. Swelling ratio, biodegradation, water vapor transmission rate (WVTR), surface morphology and the interactions between functional groups of polymers used in the hydrogel were evaluated. Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) test of extracted collagen indicated the presence of two different α-chains in collagen and confirmed type I collagen. The results showed that DAS content significantly affected the swelling ratio and biodegradability of hydrogels (P < 0.05). Col/Ch/Das0.5 hydrogel showed the highest swelling and biodegradability compared to other hydrogels (P < 0.05). Col/Cs/DAS hydrogels showed suitable water vapor transmission for wound dressing. The Fourier transform infrared spectroscopy (FTIR) results showed that covalent bonds formed via acetalization and Schiff base reaction. The results suggested that the prepared hydrogel from silver carp fish skin collagen has excellent potential as a new wound dressing for medical and biomedical applications such as wound healing.

Dietary nitrate accelerates the healing of infected skin wounds in mice by increasing microvascular density

As skin injuries resulting from acute trauma, burns, and chronic diseases present significant challenges to healthcare systems worldwide, the promotion of skin wound healing remains an unmet therapeutic area. Dietary nitrate serves as a crucial pathway for the production of nitric oxide, which plays various physiological roles in the body, including vasodilation, increased blood flow, and antioxidant activity. However, the impact of dietary nitrate on skin wound healing remains uncertain. This study aimed to investigate the role of dietary nitrate in infected skin wound healing using a mouse model. We created a full-thickness wound infection model in mice and examine the effects of dietary nitrate (0.5 mmol/kg/d and 1 mmol/kg/d) on wound healing. The results demonstrated that dietary nitrate significantly increased serum nitrate and nitrite levels, leading to accelerated wound healing by increasing microvascular density, promoting collagen deposition and re-epithelialization. Moreover, nitrate supplementation exhibited a certain degree of reduction in inflammatory factors within the body. Our study also found that 1 mmol/kg/d nitrate has a more effective therapeutic effect and can increase blood perfusion and expedite the formation of new blood vessels, thereby promoting skin wound healing. These results indicate that dietary nitrate presents a novel therapeutic approach for infected skin wound healing.

Stem cell-derived small extracellular vesicles embedded into methacrylated hyaluronic acid wound dressings accelerate wound repair in a pressure model of diabetic ulcer

Over the past years, the development of innovative smart wound dressings is revolutionizing wound care management and research. Specifically, in the treatment of diabetic foot wounds, three-dimensional (3D) bioprinted patches may enable personalized medicine therapies. In the present work, a methacrylated hyaluronic acid (MeHA) bioink is employed to manufacture 3D printed patches to deliver small extracellular vesicles (sEVs) obtained from human mesenchymal stem cells (MSC-sEVs). The production of sEVs is maximized culturing MSCs in bioreactor. A series of in vitro analyses are carried out to demonstrate the influence of MSC-sEVs on functions of dermal fibroblasts and endothelial cells, which are the primary functional cells in skin repair process. Results demonstrate that both cell populations are able to internalize MSC-sEVs and that the exposure to sEVs stimulates proliferation and migration. In vivo experiments in a well-established diabetic mouse model of pressure ulcer confirm the regenerative properties of MSC-sEVs. The MeHA patch enhances the effectiveness of sEVs by enabling controlled release of MSC-sEVs over 7 days, which improve wound epithelialization, angiogenesis and innervation. The overall findings highlight that MSC-sEVs loading in 3D printed biomaterials represents a powerful technique, which can improve the translational potential of parental stem cell in terms of regulatory and economic impact.

Co-assembled Supramolecular Hydrogel of Salvianolic Acid B and a Phosphopeptide for Enhanced Wound Healing

Supramolecular natural product gels (NPGs) have emerged as promising biomaterials for scalable and adjustable drug delivery systems. These gels possess biocompatibility, biodegradability, and the ability to mimic the extracellular matrix. Salvianolic acid B (SAB), derived from Salvia miltiorrhiza, a Chinese medicinal plant, exhibits various beneficial properties such as antioxidant, antifibrotic, and angiogenic effects. In our research, we serendipitously discovered that the co-assembly of SAB and a soluble phosphopeptide results in the formation of a robust and adhesive hydrogel termed 1&SAB hydrogel. This hydrogel effectively prolongs the retention time of the therapeutic agents on the skin's wound surface, thereby promoting wound healing. The hydrogel demonstrates antioxidant effects, enhances cell migration, accelerates angiogenesis, and inhibits scar hyperplasia. This innovative gel material offers a simple and efficient approach to managing skin wounds and holds promise for application in complex wound-healing treatments.

A Rapid Self-Pumping Organohydrogel Dressing with Hydrophilic Fractal Microchannels to Promote Burn Wound Healing

Burn wounds pose great challenges for conventional dressings because massive exudates oversecreted from swollen tissues and blisters seriously delay wound healing. Herein, a self-pumping organohydrogel dressing with hydrophilic fractal microchannels is reported that can rapidly drain excessive exudates with ≈30 times enhancement in efficiency compared with the pure hydrogel, and effectively promote burn wound healing. A creaming-assistant emulsion interfacial polymerization approach is proposed to create the hydrophilic fractal hydrogel microchannels in the self-pumping organohydrogel through a dynamic floating-colliding-coalescing process of organogel precursor droplets. In a murine burn wound model, the rapid self-pumping organohydrogel dressings can markedly reduce dermal cavity by ≈42.5%, accelerate blood vessel regeneration by ≈6.6 times, and hair follicle regeneration by ≈13.5 times, compared with the commercial dressing (Tegaderm). This study paves an avenue for designing high-performance functional burn wound dressings.

Sustainable Biomass Lignin-Based Hydrogels: A Review on Properties, Formulation, and Biomedical Applications

Different techniques have been developed to overcome the recalcitrant nature of lignocellulosic biomass and extract lignin biopolymer. Lignin has gained considerable interest owing to its attractive properties. These properties may be more beneficial when including lignin in the preparation of highly desired value-added products, including hydrogels. Lignin biopolymer, as one of the three major components of lignocellulosic biomaterials, has attracted significant interest in the biomedical field due to its biocompatibility, biodegradability, and antioxidant and antimicrobial activities. Its valorization by developing new hydrogels has increased in recent years. Furthermore, lignin-based hydrogels have shown great potential for various biomedical applications, and their copolymerization with other polymers and biopolymers further expands their possibilities. In this regard, lignin-based hydrogels can be synthesized by a variety of methods, including but not limited to interpenetrating polymer networks and polymerization, crosslinking copolymerization, crosslinking grafted lignin and monomers, atom transfer radical polymerization, and reversible addition-fragmentation transfer polymerization. As an example, the crosslinking mechanism of lignin-chitosan-poly(vinyl alcohol) (PVA) hydrogel involves active groups of lignin such as hydroxyl, carboxyl, and sulfonic groups that can form hydrogen bonds (with groups in the chemical structures of chitosan and/or PVA) and ionic bonds (with groups in the chemical structures of chitosan and/or PVA). The aim of this review paper is to provide a comprehensive overview of lignin-based hydrogels and their applications, focusing on the preparation and properties of lignin-based hydrogels and the biomedical applications of these hydrogels. In addition, we explore their potential in wound healing, drug delivery systems, and 3D bioprinting, showcasing the unique properties of lignin-based hydrogels that enable their successful utilization in these areas. Finally, we discuss future trends in the field and draw conclusions based on the findings presented.

Tendon-inspired hybrid hydrogel based on polyvinyl alcohol and gallic acid-lysozyme for promoting wound closure and healing

Noninvasive wound closure remains a challenge in the field of wound healing. In this study, we report the development of a cross-linked P-GL hydrogel constructed from polyvinyl alcohol (PVA) and GL (a hydrogel consisting of gallic acid and lysozyme) that effectively promotes wound closure and healing. The P-GL hydrogel exhibited a unique lamellar and tendon-like fibrous network structure, providing good thermo-sensitivity and tissue adhesiveness up to 60 MPa, as well as retaining autonomous self-healing and acid resistance capacities. In addition, the P-GL hydrogel exhibited sustained release characteristics lasting >100 h, excellent biocompatibility both in vitro and in vivo, as well as good antibacterial activity and mechanical properties. The in vivo full-thickness skin wounds model revealed the positive wound closure and healing therapeutic effects of the P-GL hydrogels were confirmed, showing a promising potential as a noninvasive wound closure and healing bio-adhesive hydrogel.

Influence of ZnO Nanoparticles on the Properties of Ibuprofen-Loaded Alginate-Based Biocomposite Hydrogels with Potential Antimicrobial and Anti-Inflammatory Effects

Hydrogels are a favorable alternative to accelerate the burn wound healing process and skin regeneration owing to their capability of absorbing contaminated exudates. The bacterial infections that occur in burn wounds might be treated using different topically applied materials, but bacterial resistance to antibiotics has become a major problem worldwide. Therefore, the use of non-antibiotic treatments represents a major interest in current research. In this study, new antibiocomposite hydrogels with anti-inflammatory and antimicrobial properties based on hyaluronic acid (HA) and sodium alginate (AG) were obtained using 4-(4,6-dimethoxy-1,3,5-triazinyl-2)-4-methylmorpholinium chloride as an activator. The combination of Ibuprofen, a non-steroidal anti-inflammatory drug commonly used to reduce inflammation, fever and pain in the body, with zinc oxide nanoparticles (ZnO NPs) was used in this study aimed at creating a complex hydrogel with anti-inflammatory and antimicrobial action and capable of improving the healing process of wounds caused by burns. FTIR spectra confirmed the cross-linking of AG with HA as well as the successful incorporation of ZnO NPs. Using electronic microscopy, it was noticed that the morphology of hydrogels is influenced by the incorporation of ZnO nanoparticles. Moreover, the incorporation of ZnO nanoparticles into hydrogels also has an influence on the swelling behavior at both pH 7.4 and 5.4. In fact, the swelling rate is lower when the amounts of the activator, HA and ZnO NPs are high. A drug release rate of almost 100% was observed for hydrogels without ZnO NPs, whereas the addition of nanoparticles to hydrogels led to a decrease in the release rate to 68% during 24 h. Cellular viability tests demonstrated the non-cytotoxic behavior of the hydrogels without the ZnO NPs, whereas a weak to moderate cytotoxic effect was noticed for hydrogels with ZnO NPs. The hydrogels containing 4% and 5% ZnO NPs, respectively, showed good antimicrobial activity against the S. aureus strain. These preliminary data prove that these types of hydrogels can be of interest as biomaterials for the treatment of burn wounds.

Sustained release of magnesium and zinc ions synergistically accelerates wound healing

Skin wounds are a major medical challenge that threaten human health. Functional hydrogel dressings demonstrate great potential to promote wound healing. In this study, magnesium (Mg) and zinc (Zn) are introduced into methacrylate gelatin (GelMA) hydrogel via low-temperature magnetic stirring and photocuring, and their effects on skin wounds and the underlying mechanisms are investigated. Degradation testing confirmed that the GelMA/Mg/Zn hydrogel released magnesium ions (Mg²⁺) and zinc ions (Zn²⁺) in a sustained manner. The Mg²⁺ and Zn²⁺ not only enhanced the migration of human skin fibroblasts (HSFs) and human immortalized keratinocytes (HaCats), but also promoted the transformation of HSFs into myofibroblasts and accelerated the production and remodeling of extracellular matrix. Moreover, the GelMA/Mg/Zn hydrogel enhanced the healing of full-thickness skin defects in rats via accelerated collagen deposition, angiogenesis and skin wound re-epithelialization. We also identified the mechanisms through which GelMA/Mg/Zn hydrogel promoted wound healing: the Mg²⁺ promoted Zn²⁺ entry into HSFs and increased the concentration of Zn²⁺ in HSFs, which effectively induced HSFs to differentiate into myofibroblasts by activating the STAT3 signaling pathway. The synergistic effect of Mg²⁺ and Zn²⁺ promoted wound healing. In conclusion, our study provides a promising strategy for skin wounds regeneration.

Physicochemical and in vitro biological evaluation of an injectable self-healing quaternized chitosan/oxidized pectin hydrogel for potential use as a wound dressing material

Injectable self-healing hydrogels are attractive materials for use as wound dressings. To prepare such hydrogels, the current study used quaternized chitosan (QCS) to improve the solubility and antibacterial activity and oxidized pectin (OPEC) to introduce aldehyde groups for Schiff's base reaction with the amine groups from QCS. Self-healing hydrogels were made by co-injection of polymer solutions at specific polymer concentrations and reagent ratios that optimized both Schiff's base reactions and ionic interactions. The optimal hydrogel displayed self-healing 30 min after cutting and continuous self-healing during continuous step strain analysis, rapid gelation (< 1 min), a storage modulus of 394 Pa, and hardness of 700 mN, and compressibility of 162 mN s. The adhesiveness of this hydrogel (133 Pa) was within a suitable range for application as a wound dressing. The extraction media from the hydrogel displayed no cytotoxicity to NCTC clone 929 cells and higher cell migration than the control. While the extraction media from the hydrogel was found not to have antibacterial properties, QCS was verified as having MIC50 of 0.04 mg/mL against both E. coli and S. aureus. Therefore, this injectable self-healing QCS/OPEC hydrogel has the potential use as a biocompatible hydrogel material for wound management.

Synthesis of New Hydrogels Involving Acrylic Acid and Acrylamide Grafted Agar-Agar and Their Application in the Removal of Cationic Dyes from Wastewater

Polyacrylic Acid grafted Agar-agar (AAc-graf-Agar), and polyacrylamide grafted Agar-Agar (AAm-graf-Agar) have been synthesised by free radical polymerisation route initiated by ammonium peroxodisulphate (APS), the grafted polymers were characterised by FTIR, TGA and SEM methods. The swelling properties were studied in deionised water and saline solution at room temperature. The prepared hydrogels were examined by removing cationic methylene blue (MB) dye from the aqueous solution, in which the adsorption kinetics and isotherms models were also investigated. It was found that the pseudo-second-order and Langmuir equations are the most suitable for the different sorption processes. The maximum dye adsorption capacity was 1035.96 mg∙g^-1 for AAc-graf-Agar in pH medium 12 and 1015.7 mg∙g^-1 for AAm-graf-Agar in neutral pH medium. This indicates that the AAc-graf-Agar hydrogel could be an excellent adsorbent for removing MB from aqueous solutions.

The Use of Hydrogel Dressings in Sulfur Mustard-Induced Skin and Ocular Wound Management

Over one century after its first military use on the battlefield, sulfur mustard (SM) remains a threatening agent. Due to the absence of an antidote and specific treatment, the management of SM-induced lesions, particularly on the skin and eyes, still represents a challenge. Current therapeutic management is mainly limited to symptomatic and supportive care, pain relief, and prevention of infectious complications. New strategies are needed to accelerate healing and optimize the repair of the function and appearance of damaged tissues. Hydrogels have been shown to be suitable for healing severe burn wounds. Because the same gravity of lesions is observed in SM victims, hydrogels could be relevant dressings to improve wound healing of SM-induced skin and ocular injuries. In this article, we review how hydrogel dressings may be beneficial for improving the wound healing of SM-induced injuries, with special emphasis placed on their suitability as drug delivery devices on SM-induced skin and ocular lesions.

Nafcillin-Loaded Photocrosslinkable Nanocomposite Hydrogels for Biomedical Applications

Skin infections are frequently treated via intravenous or oral administration of antibiotics, which can lead to serious adverse effects and may sometimes contribute to the proliferation of resistant bacterial strains. Skin represents a convenient pathway for delivering therapeutic compounds, ensured by the high number of blood vessels and amount of lymphatic fluids in the cutaneous tissues, which are systematically connected to the rest of the body. This study provides a novel, straightforward method to obtain nafcillin-loaded photocrosslinkable nanocomposite hydrogels and demonstrates their performance as drug carriers and antimicrobial efficacy against Gram-positive bacteria. The novel formulations obtained, based on polyvinylpyrrolidone, tri(ethylene glycol) divinyl ether crosslinker, hydrophilic bentonite nanoclay, and/or two types of photoactive (TiO₂ and ZnO) nanofillers, were characterized using various analytical methods (transmission electron microscopy (TEM), scanning electron microscopy-energy-dispersive X-ray analysis (SEM-EDX), mechanical tests (tension, compression, and shear), ultraviolet-visible spectroscopy (UV-Vis), swelling investigations, and via specific microbiological assays ("agar disc diffusion method" and "time-kill test"). The results reveal that the nanocomposite hydrogel possessed high mechanical resistance, good swelling abilities, and good antimicrobial activity, demonstrating a decrease in the bacteria growth between 3log₁₀ and 2log₁₀ after one hour of direct contact with S. aureus.

Hyaluronate- and Gelatin-based Hydrogels Encapsulating Doxycycline as a Wound Dressing for Burn Injury Therapy

Infection is a critical challenge in burn wound therapy. Wound dressings with antibacterial and multifunctional abilities associated with rapid burn wound healing are urgently needed. Here, we developed a bioadhesive and injectable ECM-mimicking hydrogel dressing with antibacterial capacity for burn injury therapy, which is crosslinked by dynamic boronate ester bonds between modified hyaluronate and gelatin (HG). The antibiotic doxycycline (Doxy) was encapsulated in HG networks for drug delivery around the wound sites. The HG/Doxy hydrogel dressing shows biocompatibility and antibacterial activity against Gram-positive and Gram-negative bacteria. Applying to a rat model of burn wound, the HG/Doxy hydrogel significantly speeds up wound closure by reducing the inflammatory reaction. Furthermore, the HG/Doxy hydrogel accelerates the regeneration of the skin structure by promoting collagen deposition, blood vessel regeneration, and hair follicle formation, eventually shortening the healing periods of burn wounds. These findings demonstrated the clinical potential of the HG/Doxy hydrogels as a promising burn wound dressing.

Bilayered skin substitute incorporating rutin nanoparticles for antioxidant, anti-inflammatory, and anti-fibrotic effect

Hypertrophic scarring in large burns and delayed healing in chronic wounds are consequences of prolonged and aggravated inflammation, sustained infiltration of immune cells, free radical generation, and abundance of inflammatory mediators. Therefore, it is imperative to curb hyperinflammation to expedite wound healing. In this study, rutin nanoparticles (RNPs) were synthesized without an encapsulant and incorporated into eggshell membrane powder-crosslinked gelatin-chitosan cryogels to impart antioxidant and anti-inflammatory properties for treating hyperinflammation. The resultant nanoparticles were found to be 17.53 ± 4.03 nm in size and were stable at room temperature for a month with no visible sedimentation. RNPs were found to be non-cytotoxic and exhibited anti-inflammatory (by increasing IL-10 levels) and antioxidant properties (by controlling the generation of reactive oxygen species and enhancing catalase production in human macrophages). Additionally, RNPs were found to reduce α-SMA expression in fibroblasts, thereby demonstrating their anti-scarring effect. In vivo studies with a bilayered skin substitute constituting an RNP-incorporated cryogel proved that it is biocompatible, does not induce renal toxicity, aids wound healing, and induces better re-epithelialization than the control groups at the initial stages. Thus, RNP-incorporated cryogels containing bilayered skin substitutes are an advanced and novel alternative to commercial dermo-epidermal substitutes that lack anti-inflammatory or anti-scarring properties.

Photopolymerized silk fibroin gel for advanced burn wound care

The future of burn wound treatment lies in developing bioactive dressings for faster and more effective healing and regeneration. Silk fibroin (SF) hydrogels have proven regenerative abilities and are being explored as a burn wound dressing. However, unfavorable gelation conditions limit the processability and clinical application. Herein a white light-responsive photopolymerization technique was adapted for gelation via photooxidation of tyrosine. To render the gel suitable for application to irregular and non-planar burn surfaces, SF gel-incorporated dressing (SFD) was fabricated. The mild gelation conditions using white light afforded the loading of drugs for local delivery. The moisture balance ability of the dressing was confirmed by the favorable measures of swelling capacity (106 ± 1 %) and moisture retention (≈10 h). The in vitro cytocompatibility of the gel was confirmed using HaCaT cells. Finally, in vivo performance of the SFD was tested on a second-degree burn in a rodent model. The gross analysis and histological assessment revealed scarless healing in SFD-treated groups. Overall, the SFD developed in this work is shown to be a promising candidate for advanced burn wound care.

Comprehensive review of the use of hydrogel spacers prior to radiation therapy for prostate cancer

OBJECTIVES

To provide a comprehensive narrative review of the published data on the impact of hydrogel spacers on rectal dosimetry and toxicity and to outline the practicalities of inserting hydrogel spacers.

RESULTS

A growing body of evidence suggests that the administration of hydrogel spacers is safe and is associated with limited peri-operative morbidity. The impact on rectal dosimetry has been clearly established and use of hydrogel spacers is associated with reduced rectal morbidity. These results have been corroborated by several Phase II and III clinical trials and subsequent meta-analysis. There are several areas for future research, including the role of hydrogel spacers in prostate stereotactic beam radiotherapy and post-radiotherapy local recurrence.

CONCLUSIONS

Hydrogel spacers provide a low-morbidity method to potential reduce rectal toxicity after radiation therapy in men with prostate cancer. Data outlining sexual function and oncological outcomes are limited to date. Future studies, currently being conducted, may provide further clarification of the role of hydrogel spacers in prostate cancer management.

Prevalence of Thrombocytopenia in the First Week After Burn Injury and Its Relationship With Burn Severity in Shahid Motahari Hospital Over a Period of 6 Months in 2017

A platelet count of less than 150,000 per microliter of blood is called thrombocytopenia. Platelet count monitoring is essential in the care of burn patients. The aim of this study was to evaluate platelet count in groups of patients with different percentage of burns on the body surface and its relationship with the severity of burns and mortality. This retrospective descriptive cross-sectional study was performed on patients admitted to Shahid Motahari Hospital over a period of six months. The study was conducted on burn patients who were admitted to the hospital on the first day after injury. Patients were divided into two groups of with or without thrombocytopenia in the first week. Demographic information and treatment information about the patients were recorded. SPSS V.26 software was used for the statistical analysis of data. In this study, the prevalence of thrombocytopenia in the first week after burns was 36%. The variables of age, sex, duration of hospitalization, burn agent, percentage of burns and use of silver sulfadiazine ointment were significantly different in the two groups of patients. The group without thrombocytopenia had a mortality rate of 5.1%, while the group with thrombocytopenia had a rate of 32.2%. Based on the results of this study, thrombocytopenia is significantly associated with mortality in burn patients. Furthermore, the results of this study indicate that age, sex, burn agent, percentage of burns, and the use of silver sulfadiazine ointment have a clear impact on the thrombocytopenic status of patients.

Advances in the Physico-Chemical, Antimicrobial and Angiogenic Properties of Graphene-Oxide/Cellulose Nanocomposites for Wound Healing

Graphene oxide (GO) and its reduced form (rGO) have recently attracted a fascinating interest due to their physico-chemical properties, which have opened up new and interesting opportunities in a wide range of biomedical applications, such as wound healing. It is worth noting that GO and rGO may offer a convenient access to its ready dispersion within various polymeric matrices (such as cellulose and its derivative forms), owing to their large surface area, based on a carbon skeleton with many functional groups (i.e., hydroxyl, carboxyl, epoxy bridge, and carbonyl moieties). This results in new synergic properties due to the presence of both components (GO or rGO and polymers), acting at different length-scales. Furthermore, they have shown efficient antimicrobial and angiogenic properties, mostly related to the intracellular formation of reactive oxygen species (ROS), which are advantageous in wound care management. For this reason, GO or rGO integration in cellulose-based matrixes have allowed for designing highly advanced multifunctional hybrid nanocomposites with tailored properties. The current review aims to discuss a potential relationship between structural and physico-chemical properties (i.e., size, edge density, surface chemistry, hydrophilicity) of the nanocomposites with antimicrobials and angiogenic mechanisms that synergically influence the wound healing phenomenon, by paying particular attention to recent findings of GO or rGO/cellulose nanocomposites. Accordingly, after providing a general overview of cellulose and its derivatives, the production methods used for GO and rGO synthesis, the mechanisms that guide antimicrobial and angiogenic processes of tissue repair, as well as the most recent and remarkable outcomes on GO/cellulose scaffolds in wound healing applications, will be presented.

Healing Efficacy of Hesperetin-Containing Chitosan Gel in Burn Wound: Formulation Design and In Vivo Evaluation

More than 5 million people require medical attention due to burn-related injuries annually. Significant research has been carried out in recent decades to develop approaches to improve the healing of burn wounds. The focus has also been on the development of natural product-based therapeutic remedies for the treatment of burn wounds. This has been done primarily due to multimodal mechanisms exhibited by some promising bioactive molecules of natural origin. Hesperetin is one such molecule that possesses strong anti-inflammatory and antioxidant properties. It is mainly obtained from citrus species. The goal of the current study was to assess how well chitosan gel that contains hesperetin may cure burn wounds. The advantage of using chitosan gel is that it could form a depot at the site and provide a protective therapeutic covering over burn wounds. In the present study, hesperetin-containing chitosan gel was prepared and evaluated for percentage hesperetin content, extrudability, spreadability, and rheological behavior. The preclinical wound healing activity was evaluated using an experimental burn wound model in Wistar rats. The results of the animal experiment showed early and better healing of burn wounds in animals treated with hesperetin-containing chitosan gel. There was 92.79% healing after 14 days of application of hesperetin-containing chitosan gel compared to 69.49% healing observed in the control group. Further, the histopathological evaluation suggested no inflammatory cell infiltration, normal epidermal growth, and normal collagen bundle arrangement in these animals. Overall the results provide proof of concept to establish the wound healing potential of hesperetin-containing chitosan gel against burn wounds.

Nanogels as Potential Delivery Vehicles in Improving the Therapeutic Efficacy of Phytopharmaceuticals

Nanogel is a promising drug delivery approach to improve the pharmacokinetics and pharmacodynamic prospect of phytopharmaceuticals. In the present review, phytopharmaceuticals with astonishing therapeutic utilities are being explored. However, their in vivo delivery is challenging, owing to poor biopharmaceutical attributes that impact their drug release profile, skin penetration, and the reach of optimal therapeutic concentrations to the target site. Nanogel and its advanced version in the form of nanoemulgel (oil-in-water nanoemulsion integrated gel matrix) offer better therapeutic prospects than other conventional counterparts for improving the biopharmaceutical attributes and thus therapeutic efficacy of phytopharmaceuticals. Nanoemulgel-loaded phytopharmaceuticals could substantially improve permeation behavior across skin barriers, subsequently enhancing the delivery and therapeutic effectiveness of the bioactive compound. Furthermore, the thixotropic characteristics of polymeric hydrogel utilized in the fabrication of nanogel/nanoemulgel-based drug delivery systems have also imparted improvements in the biopharmaceutical attributes of loaded phytopharmaceuticals. This formulation approach is about to be rife in the coming decades. Thus, the current review throws light on the recent studies demonstrating the role of nanogels in enhancing the delivery of bioactive compounds for treating various disease conditions and the challenges faced in their clinical translation.

Evaluating polymeric biomaterials to improve next generation wound dressing design

Wound healing is a dynamic series of interconnected events with the ultimate goal of promoting neotissue formation and restoration of anatomical function. Yet, the complexity of wound healing can often result in development of complex, chronic wounds, which currently results in a significant strain and burden to our healthcare system. The advancement of new and effective wound care therapies remains a critical issue, with the current therapeutic modalities often remaining inadequate. Notably, the field of tissue engineering has grown significantly in the last several years, in part, due to the diverse properties and applications of polymeric biomaterials. The interdisciplinary cohesion of the chemical, biological, physical, and material sciences is pertinent to advancing our current understanding of biomaterials and generating new wound care modalities. However, there is still room for closing the gap between the clinical and material science realms in order to more effectively develop novel wound care therapies that aid in the treatment of complex wounds. Thus, in this review, we discuss key material science principles in the context of polymeric biomaterials, provide a clinical breadth to discuss how these properties affect wound dressing design, and the role of polymeric biomaterials in the innovation and design of the next generation of wound dressings.

Ionic complexation improves wound healing in deep second-degree burns and reduces in-vitro ciprofloxacin cytotoxicity in fibroblasts

The development of new treatments capable of controlling infections and pain related to burns continues to be a challenge. Antimicrobials are necessary tools, but these can be cytotoxic for regenerating cells. In this study, antibiotic-anesthetic (AA) smart systems obtained by ionic complexation of polyelectrolytes with ciprofloxacin and lidocaine were obtained as films and hydrogels. Ionic complexation with sodium alginate and hyaluronate decreased cytotoxicity of ciprofloxacin above 70% in a primary culture of isolated fibroblasts (p < 0.05). In addition, the relative levels of the proteins involved in cell migration, integrin β1 and p-FAK, increased above 1.5 times (p < 0.05) with no significant differences in cell mobility. Evaluation of the systems in a deep second-degree burn model revealed that reepithelization rate was AA-films = AA-hydrogels > control films > no treated > reference cream (silver sulfadiazine cream). In addition, appendage conservation and complete dermis organization were achieved in AA-films and AA-hydrogels. Encouragingly, both the films and the hydrogels showed a significantly superior performance compared to the reference treatment. This work highlights the great potential of this smart system as an attractive dressing for burns, which surpasses currently available treatments.

Polymer-Based Hydrogels Enriched with Essential Oils: A Promising Approach for the Treatment of Infected Wounds

Among the factors that delay the wound healing process in chronic wounds, bacterial infections are a common cause of acute wounds becoming chronic. Various therapeutic agents, such as antibiotics, metallic nanoparticles, and essential oils have been employed to treat infected wounds and also prevent the wounds from bacterial invasion. Essential oils are promising therapeutic agents with excellent wound healing, anti-inflammatory and antimicrobial activities, and good soothing effects. Some essential oils become chemically unstable when exposed to light, heat, oxygen, and moisture. The stability and biological activity of essential oil can be preserved via loading into hydrogels. The polymer-based hydrogels loaded with bioactive agents are regarded as ideal wound dressings with unique features, such as controlled and sustained drug release mechanisms, good antibacterial activity, non-toxicity, excellent cytocompatibility, good porosity, moderate water vapour transmission rate, etc. This review addresses the pre-clinical outcomes of hydrogels loaded with essential oils in the treatment of infected wounds.

The Discovery and Development of Natural-Based Biomaterials with Demonstrated Wound Healing Properties: A Reliable Approach in Clinical Trials

Current research across the globe still focuses strongly on naturally derived biomaterials in various fields, particularly wound care. There is a need for more effective therapies that will address the physiological deficiencies underlying chronic wound treatment. The use of moist bioactive scaffolds has significantly increased healing rates compared to local and traditional treatments. However, failure to heal or prolonging the wound healing process results in increased financial and social stress imposed on health institutions, caregivers, patients, and their families. The urgent need to identify practical, safe, and cost-effective wound healing scaffolding from natural-based biomaterials that can be introduced into clinical practice is unequivocal. Naturally derived products have long been used in wound healing; however, clinical trial evaluations of these therapies are still in their infancy. Additionally, further well-designed clinical trials are necessary to confirm the efficacy and safety of natural-based biomaterials in treating wounds. Thus, the focus of this review is to describe the current insight, the latest discoveries in selected natural-based wound healing implant products, the possible action mechanisms, and an approach to clinical studies. We explore several tested products undergoing clinical trials as a novel approach to counteract the debilitating effects of impaired wound healing.

Dissolvable wound dressing loaded with silver nanoparticles together with ampicillin and ciprofloxacin

Aim: The current study is focused on the development of water-soluble wound dressings, which are potential dressings for the treatment of burn wounds. Materials & methods: Sodium alginate-based dissolvable wound dressings were prepared and loaded with silver nanoparticles and various antibiotics (ampicillin and ciprofloxacin) followed by characterization and in vitro antibacterial studies. Results & conclusions: The prepared sodium alginate-based dissolvable wound dressing exhibited good porosity, water uptake and moisture content, promising antibacterial activity, high absorption capacity of simulated wound exudates, excellent water vapor transmission rate in the range of 2000 to 5000 g/m² day^-1, sustained drug-release profiles and water solubility. The wound dressings were active against Proteus mirabilis, Staphylococcus aureus, Proteus vulgaris, Escherichia coli and Klebsiella aeruginosa strains of bacteria. The results obtained revealed the wound dressing as potential wound dressings for burn wounds and sensitive skin.

Exosomes of mesenchymal stem cells delivered from methacrylated hyaluronic acid patch improve the regenerative properties of endothelial and dermal cells

Wound care management urgently needs the development of innovative smart wound dressings. The complexity of the wound often requires the use of personalized medication and the advent of three-dimensional (3D) bioprinting fits strongly with this need. In this view, in the present work a methacrylated hyaluronic acid (MeHA) bioink was tested for the fabrication of advanced smart patches as a delivery system of exosomes derived from human mesenchymal stem cells (hMSC-EXOs) suitable for wound healing purposes. MeHA patches were realized by 3D bioprinting technique and they were loaded with hMSC-EXOs. The 3D printed MeHA patches revealed improved mechanical performance, appropriate swelling ratio, extended degradation time, and suitable biocompatibility. Furthermore, MeHA patches loaded with hMSC-EXOs improved the proliferation, migration, angiogenic ability, and expression of specific markers related to wound healing process in human fibroblasts and human endothelial cells.

Preparation and Characterization of Eco-Friendly Transparent Antibacterial Starch/Polyvinyl Alcohol Materials for Use as Wound-Dressing

In this study, eco-friendly and transparent starch-based/polyvinyl alcohol/citric acid composite films are evaluated for their efficacy as wound dressing materials. The starch/polyvinyl alcohol (PVA) materials with added citric acid (0.46-1.83 wt%) and glycerol were made and handled based on the modified casting method. This new formulation decreases the amount of PVA used in the conventional preparation method. Citric acid ensures an appropriate antibacterial environment for wound-dressing materials. The mechanical, chemical, and surface morphological properties of such films were assessed and analyzed by tensile strength tests, UV-Vis spectrometry, swelling index, and scanning electron microscopy (SEM). Furthermore, the water vapor transmission (WVT) quantity was measured for an ideal wound-healing process to investigate an optimal moisture environment around the wound bed. Moreover, the pH level of the dressings was measured to examine the possibility of bacterial growth around these starch-based films. Additionally, the films' in-vitro antibacterial activities were studied against the two most common Gram-positive and Gram-negative bacteria (Escherichia coli and Staphylococcus aureus). The new starch-based dressings demonstrated suitable degradation, antibacterial activity, fluid absorption, and adequate mechanical strength, representing wound-dressing materials' vital features.

An Updated Account On Formulations And Strategies For The Treatment Of Burn Infection – A Review

Background:

Burn injury is considered one of the critical injuries of the skin. According to WHO (World Health Organization), approximately 3,00,000 deaths are caused each year mainly due to fire burns, with additional deaths attributed to heat and other causes of burn e.g., electric devices, chemical materials, radioactive rays, etc. More than 95% of burn injuries occur in developing countries.

Introduction:

Burn injuries have been a prominent topic of discussion in this present era of advancements. Burns are one of the common and devastating forms of trauma. Burn injuries are involved in causing severe damage to skin tissues and various other body parts triggered particularly by fire,blaze, or exposure to chemicals and heated substances. They leave a long-lasting negative impact on the patients in terms of their physical and mental health.

Method:

The various methods and bioactive hydrogels, a viable and widely utilised approach for treating chronic wounds remains a bottleneck. Many traditional approaches such as woven material, conventional antimicrobial agents, hydrogel sheets, creams are utilised in wound healing. Nowadays, lipid-based nanoparticles, nanofibres systems, and foam-based formulations heal the wound.

Result:

The prepared formulation shows wound healing activity when tested on rat model. The nanofibres containing SSD help in the burn-wound healing study on Male Sprague Dawley (SD) rats. The healing effect on rats was examined by western blot analysis, digital camera observation, and histological analyses.

Conclusion:

Burn is also considered the most grievous form of trauma. Nowadays, several large and foam-based formulations are used in wound healing, which heals the wound better than previously existing formulations and is less prone to secondary infection. Recently, nanofiber delivery has piqued the interest of academics over the years because of its excellent features, which include an extraordinarily high surface to volume ratio, a highly porous structure, and tiny pore size.

Recent Advances in Polysaccharide-Based Physical Hydrogels and Their Potential Applications for Biomedical and Wastewater Treatment

Polysaccharides have been widely employed to fabricate hydrogels owing to their intrinsic properties including biocompatibility, biodegradability, sustainability, and easy modification. However, a considerable amount of polysaccharide-based hydrogels are prepared by chemical crosslinking method using organic solvents or toxic crosslinkers. The presence of reaction by-products and residual toxic substances in the obtained materials cause a potential secondary pollution risk and thus severely limited their practical applications. In contrast, polysaccharide-based physical hydrogels are preferred over chemically derived hydrogels and can be used to address existing drawbacks of chemical hydrogels. The polysaccharide chains of such hydrogel are typically crosslinked by dynamic non-covalent bonds, and the co-existence of multiple physical interactions stabilize the hydrogel network. This review focuses on providing a detailed outlook for the design strategies and formation mechanisms of polysaccharide-based physical hydrogels as well as their specific applications in tissue engineering, drug delivery, wound healing, and wastewater treatment. The main preparation principles, future challenges, and potential improvements are also outlined. The authors hope that this review could provide valuable information for the rational fabrication of polysaccharide-based physical hydrogel. The specific research works listed in the review will provide a systematic and solid research basis for the reliable development of polysaccharide-based physical hydrogel. This article is protected by copyright. All rights reserved.

Mimic Pork Rinds from Plant-Based Gel: The Influence of Sweet Potato Starch and Konjac Glucomannan

This study investigated the effect of sweet potato starch (SPS) and konjac glucomannan (KGM) on the textural, color, sensory, rheological properties, and microstructures of plant-based pork rinds. Plant-based gels were prepared using mixtures of soy protein isolate (SPI), soy oil, and NaHCO₃ supplemented with different SPS and KGM concentrations. The texture profile analysis (TPA) results indicated that the hardness, cohesiveness, and chewiness of the samples improved significantly after appropriate SPS and KGM addition. The results obtained via a colorimeter showed no significant differences were found in lightness (L*) between the samples and natural pork rinds after adjusting the SPS and KGM concentrations. Furthermore, the rheological results showed that adding SPS and KGM increased both the storage modulus (G’) and loss modulus (G’’), indicating a firmer gel structure. The images obtained via scanning electron microscopy (SEM) showed that the SPS and KGM contributed to the formation of a more compact gel structure. A mathematical model allowed for a more objective sensory evaluation, with the 40% SPS samples and the 0.4% KGM samples being considered the most similar to natural pork rinds, which provided a comparable texture, appearance, and mouthfeel. This study proposed a possible schematic model for the gelling mechanism of plant-based pork rinds: the three-dimensional network structures of the samples may result from the interaction between SPS, SPI, and soybean oil, while the addition of KGM and NaHCO₃ enabled a more stable gel structure.

Burns in Israel: Etiologic, Demographic, and Clinical trends—A 9-Year Updated Comprehensive Study, 2004–2010 versus 2011–2019

Based on the Israeli National Trauma Registry (INTR) data, this study reports etiological, demographic, and clinical trends and includes all admissions to burn and trauma centers across Israel from 2011 to 2019 and compares these with 2004 to 2010 rates. From 2011 to 2019, 5,710 patients were admitted to burn centers across Israel. Children aged 0 to 1 years (25.9%), non-Jews (40.7%), and males (67.2%) remain the main groups of the burn casualties. Most of the casualties sustained 1 to 9% total body surface area (TBSA) burns with various depths. Scalds were less fatal than fire/flame-related casualties (<1 vs. 11.5%). Fewer surgical procedures were conducted for burns under 9% TBSA compared with greater TBSA. The percentage of TBSA and burn depth were found to be the most significant predictor of mortality among all age groups (>200 times increased risk with full-thickness burns >30% TBSA burn) and correlated with prolonged length of stay (>7 days).

Supramolecular Thermo-Contracting Adhesive Hydrogel with Self-Removability Simultaneously Enhancing Noninvasive Wound Closure and MRSA-Infected Wound Healing

Conventional wound closure and dressing are two crucial, time-consuming but isolated principles in wound care. Even though tissue adhesive opens a new era for wound closure, the method and biomaterial that can simultaneously achieve noninvasive wound closure and promote wound healing are highly appreciated. Herein, a novel supramolecular poly(N-isopropylacrylamide) hybrid hydrogel dressing composed of quaternized chitosan-graft-β-cyclodextrin, adenine, and polypyrrole nanotubes via host-guest interaction and hydrogen bonds is developed. The hydrogel demonstrates thermal contraction of 47% remaining area after 2 h at 37 ℃ and tissue adhesion of 5.74 kPa, which are essential for noninvasive wound closure, and multiple mechanical and biological properties including suitable mechanical properties, self-healing, on-demand removal, antioxidant, hemostasis, and photothermal/intrinsic antibacterial activity (higher 99% killing ratio within 5 min after irradiation). In both full-thickness skin incision and excision wound models, the hydrogel reveals significant wound closure after 24 h post-surgery. In acute and methicillin-resistant Staphylococcus aureus-infected wound and photothermal/intrinsic antibacterial activity assays, wounds treated with the hydrogel demonstrate enhanced wound healing with rapid wound closure rate, mild inflammatory response, advanced angiogenesis, and well-arranged collagen fibers. Altogether, the results indicate the hydrogel is promising in synchronously noninvasive wound closure and enhanced wound healing.

Nanoengineered therapeutic scaffolds for burn wound management

BACKGROUND

Wound healing is a complex process, and selecting an appropriate treatment is crucial and varies from one wound to another. Among injuries, burn wounds are more challenging to treat. Different dressings and scaffolds come into play when skin is injured. These scaffolds provide the optimum environment for wound healing. With the advancements of nanoengineering, scaffolds have been engineered to improve wound healing with lower fatality rates.

OBJECTIVES

Nanoengineered systems have emerged as one of the promising candidates for burn wound management. This review paper aims to provide an in-depth understanding of burn wounds and the role of nanoengineering in burn wound management. The advantages of nanoengineered scaffolds, their properties, and their proven effectiveness have been discussed. Nanoparticles and nanofibers-based nanoengineered therapeutic scaffolds provide optimum protection, infection management, and accelerated wound healing due to their unique characteristics. These scaffolds increase cell attachment and proliferation for desired results.

RESULTS

The literature review suggested that the utilization of nanoengineered scaffolds has accelerated burn wound healing. Nanofibers provide better cell attachment and proliferation among different nanoengineered scaffolds due to their 3D structure mimics the body's extracellular matrix.

CONCLUSION

With the application of these advanced nanoengineered scaffolds, better burn wound management is possible due to sustained drug delivery, better cell attachment, and an infection-free environment.

Hydrogels in Burn Wound Management-A Review

Inert hydrogels are of a great importance in burn first aid. Hydrogel dressings may be an alternative to cooling burn wounds with streaming water, especially in cases of mass casualty events, lack of clean water, hypothermia, or large extent of burns. Hydrogels that contain mostly water evacuate the heat cumulating in the skin by evaporation. They not only cool the burn wound, but also reduce pain and protect the wound area from contamination and further injuries. Hydrogels are ideally used during the first hours after injury, but as they do not have antimicrobial properties per se, they might not prevent wound infection. The hydrogel matrix enables incorporating active substances into the dressing. The active forms may contain ammonium salts, nanocrystal silver, zinc, growth factor, cytokines, or cells, as well as natural agents, such as honey or herbs. Active dressings may have antimicrobial activity or stimulate wound healing. Numerous experiments on animal models proved their safety and efficiency. Hydrogels are a new dressing type that are still in development.

Supramolecular Hydrogels Developed from Mafenide and Indomethacin as a Plausible Multidrug Self-Delivery System as Antibacterial and Anti-inflammatory Topical Gels

Following a structural rationale, a series of simple organic salts derived from mafenide (a drug for treating burn wounds) and n-alkyl carboxylic acids (Me-(CH₂)_n-COOH; n = 1-3, 10-15) and various nonsteroidal anti-inflammatory drugs (NSAIDs), namely, indomethacin (IND), diclofenac (DIC), meclofenamic acid (MEC), tolfenamic acid (TOL), and flufenamic acid (FLU) (designated as salts 1-14, respectively) were synthesized as potential hydrogelators. Gelation studies revealed that mafenide n-alkyl carboxylates with n = 11-14, i.e., salts 5-8, and the indomethacin salt of mafenide, i.e., salt 10, were hydrogelators. The corresponding hydrogels, namely, 5(HG)-8(HG) and 10(HG), were characterized by table-top and dynamic rheology and high-resolution transmission electron microscopy (HR-TEM). Single-crystal structures of the nongelator salts 1-3 and the gelator salt 10 were determined by X-ray diffraction. The results obtained from various studies, which included the solubility, biostability, biocompatibility (MTT assay), and anti-inflammatory (PGE₂ assay) response of salt 10, the antibacterial response (zone inhibition assay) of salt 10, its components, and 10(HG), and the release of salt 10 in vitro from the corresponding hydrogel bed to the bulk solvent at 37 °C in 24 h, suggested their plausible use in developing multidrug-derived topical hydrogels for self-delivery applications.