Search Results (997)

Rapid rewarming is the most conventional and primary treatment for frostbite, yet effective adjunctive strategies remain absent. Conventional wound dressings, such as therapeutic hydrogels, tend to freeze and lack the necessary rewarming ability, rendering them unsuitable for direct application. Herein, we engineered an environmentally tolerant photothermal hydrogel, named 5A-Gel, featuring anti-swelling, anti-pressure, antioxidant, anti-freezing, and anti-drying capacities, for the treatment of frostbite. 5A-Gel was formed via dynamic crosslinking between gelatin and tea polyphenols in a glycerol/water solvent system. The incorporation of glycerol endowed the hydrogel with superior anti-swelling, anti-freezing, and anti-drying performance (remaining flexible at −20 °C and 37 °C for at least 60 days), along with concentration-dependent antioxidant activity due to tea polyphenols. Furthermore, 5A-Gel exhibited excellent photothermal effects, maintaining stable temperature and softness under 808 nm laser irradiation with robust cyclic durability. In addition, 5A-Gel showed slow degradability, excellent hemocompatibility, and favorable in vivo biosafety. Functionally, in a mouse frostbite wound model, photothermal rewarming therapy using 5A-Gel markedly expedited frostbite healing, promoting re-epithelialization, enhancing collagen deposition, alleviating inflammatory response, and stimulating neovascularization. Therefore, the as-prepared 5A-Gel serves as a competent therapeutic platform for in situ frostbite treatment and offers innovative principles for the rational engineering of high-performance hydrogel systems targeting frostbite tissue injuries. Full article

Polysaccharide-based hydrogels represent promising platforms for the development of bioactive wound dressings due to their biocompatibility, bioadhesive properties, and ability to maintain a moist environment at the wound interface. In this study, polymeric films were developed from natural polysaccharides incorporating olive mill wastewater (OMW) as a natural antibacterial agent. Chitosan (medium molecular weight), sodium alginate, sodium hyaluronate, and xanthan gum were selected to prepare hydrogel formulations either as single polymers or binary mixtures. Hydrogels were prepared by aqueous dispersion under magnetic stirring and subsequently converted into films using a solvent casting method. The resulting films were characterized in terms of rheological behavior, pH, morphology, thickness and water content. The obtained hydrogel films showed good casting ability, producing smooth and homogeneous matrices with adequate deformability and skin adhesion. Furthermore, they demonstrated a suitable capacity to absorb and retain water, mimicking the management of wound exudate. OMW was incorporated into the hydrogel formulations as a source of phenolic compounds with well-known antioxidant and antimicrobial properties. The presence of these bioactive compounds provides the films with potential antibacterial and antibiofilm activity against clinically relevant multidrug-resistant staphylococcal strains. These findings suggest that OMW-loaded polysaccharide hydrogels represent a promising and sustainable strategy for the development of antibacterial films for wound healing applications. Full article

Background: Thymoquinone (TQ), a bioactive compound derived from Nigella sativa L., exhibits promising antioxidant, anti-inflammatory, and wound-healing properties; however, its clinical application is limited by poor solubility and instability. Methods: In this study, three electrospun nanofiber systems based on different polymeric matrices, PVP (N1), PVP/HPβCD (N2), and PVP/PCL (N3), were developed as potential wound dressing materials for controlled TQ delivery. Results: All formulations produced uniform nanofibrous structures with TQ molecularly dispersed within the polymer matrix, as confirmed by SEM, XRPD, and FTIR analyses. The composition of the nanofibers significantly influenced their physicochemical and functional properties. The N2 system, containing hydroxypropyl-β-cyclodextrin (HPβCD), exhibited the smallest fiber diameter (~208 nm), the fastest drug release, and enhanced antioxidant and anti-inflammatory activity due to improved TQ solubility. In contrast, the N3 system, incorporating polycaprolactone (PCL), formed thicker fibers (~1089 nm) and demonstrated sustained release behavior, the highest mucoadhesion, and the most pronounced wound-healing effect (90% closure after 24 h). Stability studies revealed that HPβCD significantly improved TQ resistance to thermal, humidity, and photolytic degradation, whereas the PVP-based system without stabilizers showed the lowest stability. Principal component analysis (PCA) confirmed that nanofiber performance is governed by two key factors: drug availability and sustained release combined with bioadhesion. Importantly, wound-healing efficiency correlated more strongly with the latter. Conclusions: The results demonstrate that rational design of polymer composition enables modulation of TQ delivery and biological response. Among the tested systems, PVP/PCL nanofibers appear to be the most promising candidates for wound-dressing applications due to their ability to provide sustained drug release and enhance tissue regeneration. Full article

Multifunctional dressings capable of maintaining a moist environment, supporting tissue regeneration, and delivering bioactive compounds are increasingly being explored as promising strategies for burn wound management. In this study, alginate-based emulgel patches incorporating hydrophilic and lipophilic plant extracts were developed by extrusion-based 3D printing as potential topical systems for burn wound applications. The formulation included sodium alginate, hyaluronic acid, and hydroglyceric extracts of Calendula officinalis, Matricaria chamomilla, and Plantago major, as well as oily extracts of Hippophae rhamnoides and Hypericum perforatum. The emulgel was evaluated for pH, rheological behaviour, spreadability, physical stability, apparent hydrodynamic size distribution, zeta potential, total polyphenol content, and antioxidant activity. Following Ca²⁺-induced crosslinking, uniform and flexible 3D-printed patches were obtained and further characterised for pharmacotechnical, physicochemical, structural, functional, and biological properties. The emulgel exhibited suitable characteristics for extrusion-based printing, while the resulting patches showed good dimensional uniformity, flexibility, swelling capacity, water vapour transmission, and surface pH compatible with topical application. FTIR, DLS, SEM, and SEM–EDX analyses supported the formation of a Ca²⁺-crosslinked alginate network and confirmed the presence of structurally heterogeneous domains with homogeneous calcium distribution. The patches retained plant-derived bioactive compounds, with a total polyphenol content of 0.2878 ± 0.016 mg GAE/g hydrated patch, and showed improved antioxidant activity compared with the corresponding emulgel. In vitro release studies indicated the time-dependent diffusion of polyphenols over 24 h, with cumulative release reaching 64.42%. The patches also exhibited a water vapour transmission rate of 1270 ± 93 g/m²/24 h, indicating adequate moisture regulation. HaCaT cell viability remained above 90% at lower tested concentrations, demonstrating a favourable biocompatibility profile. Overall, the developed 3D-printed alginate emulgel patches represent promising multifunctional systems for potential burn wound management and warrant further preclinical investigation. Full article

The extracellular matrix (ECM) provides a dynamic microenvironment that regulates cell proliferation, migration, and tissue remodeling during wound healing. However, replicating the structural and functional complexity and ECM heterogeneity of native skin ECM remains challenging with conventional single-material hydrogels. Recent advances in multimaterial 3D bioprinting have enabled the spatial integration of diverse biomaterials within a single construct. Lignocellulose has attracted increasing attention as a promising biomaterial for recreating key structural features of the native ECM because of its fibrous architecture, mechanical strength, and biocompatibility. This review offers a comprehensive and integrated perspective on the use of lignocellulose-based multimaterial printing to recreate ECM-mimicking architectures, an underexplored area at the intersection of biomaterials and biofabrication. The roles of cellulose, hemicellulose, and lignin in printability, scaffold stability, porosity, bioactivity, and wound-healing performance are discussed. Representative studies have demonstrated that lignocellulose-based multimaterial bioinks provide porous architectures that support cell adhesion, proliferation, and tissue regeneration. These benefits are accompanied by improved mechanical performance, as cellulose nanofibers exhibit elastic moduli exceeding 100 GPa, and lignin-containing hydrogels have achieved compressive moduli of up to 135 kPa. Such mechanical advantages make lignocellulosic materials particularly attractive for fabricating ECM-mimicking scaffolds that require long-term structural integrity. Finally, key design considerations and current limitations associated with lignocellulose-based multimaterial bioprinting are critically discussed. A framework for the rational design of lignocellulose-based multimaterial bioinks is presented, together with future directions toward gradient and adaptive scaffolds, smart wound dressings, and advanced wound-healing applications. Full article

Diabetic wounds remain a major clinical challenge due to impaired healing associated with persistent inflammation, oxidative stress, and microvascular dysfunction. Plasma-based therapies have emerged as promising approaches for promoting tissue repair; however, comparative evidence regarding different plasma modalities remains limited. In this study, we evaluated and compared the effects of atmospheric pressure cold plasma (APCP) and plasma-activated water (PAW) on wound healing in a streptozotocin-induced diabetic rat model. Forty Wistar albino rats were randomly assigned to five groups: isotonic wet dressing, hydrocolloid dressing, APCP treatment, PAW application, and a non-diabetic control group. Wound healing was assessed using macroscopic evaluation, histopathological analysis, and biochemical measurements of systemic oxidative status. PAW treatment significantly accelerated wound closure during the early healing phase compared with conventional dressing methods (p < 0.05). Histological findings demonstrated enhanced re-epithelialization, increased collagen deposition, and improved follicular regeneration in the PAW group. Although total oxidant status (TOS) did not differ significantly among groups (p = 0.996), total antioxidant status (TAS) was significantly increased following PAW treatment (p < 0.05), indicating a more favorable systemic antioxidant profile. These findings suggest an association between improved wound healing and a more favorable systemic antioxidant profile following PAW treatment. However, because local wound-level redox parameters and molecular markers were not assessed, the contribution of redox-related mechanisms remains to be clarified. Moreover, PAW demonstrated superior therapeutic efficacy compared with direct plasma application, highlighting its potential as a non-invasive approach for diabetic wound management. Full article

Background: Interest in advanced wound dressings for clinical applications is increasing, with biopolymer-based formulations emerging as an effective strategy for wound management. Objectives: This study aimed to develop and characterize sponge-like biopolymeric matrices for the topical delivery of indomethacin as a model anti-inflammatory drug. Methods: Matrices were prepared by combining collagen and methylcellulose (MC) gels in varying ratios, followed by lyophilization. Physicochemical characterization included FT-IR, SEM, contact angle, and water absorption analysis. Biological evaluation involved enzymatic degradation, while biopharmaceutical and pharmacological assessments included in vitro drug release and in vivo testing in Wistar rats with experimentally induced burns. Results: FT-IR analysis confirmed that collagen’s triple-helical structure was preserved in the presence of MC and indomethacin for the samples with maximum 25% methylcellulose. SEM analysis revealed a microporous network with integrated cellulose fibers, where pore size decreased with higher MC content. Compressive strength measurements demonstrated enhanced mechanical resistance with increasing MC content, indicating improved structural stability of the matrices. Moreover, increased MC content led to higher contact angle values but maintained hydrophilicity, while formulations with up to 25% MC exhibited good absorption capacity and structural integrity. Enzymatic degradation studies confirmed that matrices with at least 75% collagen content maintained their structural integrity over time, favoring prolonged application and sustained drug delivery. In vitro drug release followed a biphasic profile, supporting rapid initial anti-inflammatory action followed by gradual release of the drug. In vivo animal studies demonstrated accelerated wound healing in treated rats for all tested matrices. Conclusions: Overall, the developed indomethacin-loaded biopolymeric matrices showed promising structural, functional, and therapeutic properties for effective wound treatment. Full article

Background/Objectives: Epidermolysis bullosa (EB) comprises a heterogeneous group of rare inherited skin-fragility disorders in which even minimal trauma can cause blistering, chronic wounds, scarring, and functional impairment. After surgical release of EB hand deformities, wound coverage is challenging because autologous split-thickness skin grafting creates an additional donor-site wound in already fragile tissue. This preliminary case series reports our single-center pediatric experience using intact fish skin grafting (iFSG) as an adjunct after EB hand surgery. Methods: We conducted an observational case series of five pediatric patients with dystrophic EB, including eight operated hands, treated between December 2022 and December 2025. iFSG was applied after the release of contractures and/or pseudosyndactyly. Primary outcomes were time to complete re-epithelialization, need for re-application, need for autologous grafting, and early complications. Secondary outcomes included dressing-related pain assessed with an age-appropriate visual analog scale during awake dressing care, dressing burden, and early recurrence signals. Results: The iFSG application was feasible in all cases. One localized second application was required, and no patient required autologous split-thickness skin grafting. Mean dressing-related pain was 1.6 on the visual analog scale, and mean time to complete re-epithelialization was 47.6 days. No allergic reactions occurred. Healing was slower in the two most severe bilateral mitten-hand cases, and one patient developed limited dorsal disepithelialization attributed to prolonged dressing contact on extremely fragile skin. One partial recurrence of pseudosyndactyly was observed during follow-up without the need for revision surgery. Conclusions: iFSG was feasible in this small preliminary pediatric dystrophic EB hand surgery series and may provide a biologically active scaffold that supports secondary closure while avoiding autologous donor-site creation. Because of the rarity of the disease, the limited sample size, the absence of a comparator group, and the limited follow-up, these findings should be interpreted cautiously. Larger multicenter studies with standardized functional, pain, recurrence, and caregiver-reported outcomes are needed to define the role of iFSG in EB hand reconstruction. ABILHAND-Kids was also administered to patients/caregivers and suggested encouraging perceived improvement in postoperative hand use and independence in daily activities. Full article

The application of silk sericin as a polymeric biomaterial has recently gained interest, although its film was found to be fragile, exhibiting brittleness when subjected to relatively slight stress, and it also displayed higher water solubility. This study focused on the enhanced physico-mechanical properties of the three films obtained by the crosslinking of sericin protein from three silkworm cocoons with poly (vinyl alcohol) (PVA) to reduce phase separation and solubilization of the films by promoting miscibility between sericin and PVA. The findings demonstrated how crosslinking with glutaraldehyde enhanced thermal stability and tensile strength and controlled the solubility of the three sericin–PVA films. The sericin from G. postica, G. rufobrunnea, and Argema mimosae is composed of serine, aspartic acid, and glutamic acid, which make up 80% of the total polar amino acids. X-ray diffraction (XRD) patterns showed that sericin–PVA films have semicrystalline features, representing amorphous and crystalline regions. The XRD results also indicated that the Saturniidae sericin–PVA film (Sat-SPF), Gonometa postica sericin–PVA film (GP-SPF), and Gonometa rufobrunnea sericin–PVA film (GR-SPF) have crystallinity percentages of 66.4%, 55.9%, and 17.7%, respectively. The moisture vapor transmission rate (MVTR) values observed in this study ranged from 991.2 to 5160 g/m²/24 h, indicating that these films can effectively regulate moisture levels in wounds. The swelling capacity of the three sericin–PVA composite films depends on the crosslinking density of their structures and was also found to be sensitive to the pH of the aqueous media, demonstrating their hydrophilic nature and potential use in drug delivery systems. The water vapor permeability of sericin–PVA films increased with higher environmental relative humidity (RH) and moisture content within the films. The elongation at break for GP-SPF (107.2% ± 3.1) and Sat-SPF (73.0% ± 4.1) was significantly higher than in GR-SPF (29.3% ± 2.3). However, their tensile strength and elastic modulus were lower than those of GR-SPF. These results show that the number of polar groups (amino and hydroxyl groups) from both sericin and PVA influences all the properties of the sericin–PVA composite films. The three sericin–PVA solutions were found to have antibacterial efficacy against three Gram-positive and one Gram-negative bacteria over 24 h. Scanning electron microscopy (SEM) images revealed a rough surface with a granular network pattern, which supports the potential use of sericin–PVA films for cell adhesion and proliferation, which are essential for biomedical wound dressing applications. Full article

Developing hydrogel dressings that simultaneously achieve robust wet tissue adhesion, mechanical stability, antibacterial activity, and oxidative stress regulation remains challenging. In this study, a dual-network poly (thioctic acid)/ammonium glycyrrhizinate (PTA/AG) hydrogel was developed through thermally induced ring-opening polymerization (ROP) of TA and sodium thioctate (TA-Na) to form a primary network, followed by the formation of an AG-driven secondary network during cooling. TA-Na improved the aqueous processability of TA, while the AG secondary network reinforced the stability of the PTA primary network. The resulting hydrogel exhibited a crossover strain of 454% and a wet adhesion strength of up to 16.37 kPa on porcine skin. In addition, the hydrogel showed strong antibacterial activity against S. aureus (>99%), high cytocompatibility (>95% cell viability), and effective free-radical-scavenging activity (>77% scavenging of both DPPH and ABTS radicals). Notably, the hydrogel exhibited effective intracellular antioxidant activity, reducing ROS levels to near those of the control group and increasing SOD activity by approximately 13-fold and the GSH/GSSG ratio by 97.83% relative to the H₂O₂ group. Overall, the PTA/AG hydrogel is a promising candidate for multifunctional wound dressing applications. Full article

This study investigates physicochemical, mechanical, and thermal effects of St. John’s wort (JW) oil on gelatin-based films for potential biomedical applications as there is limited research on gelatin biomaterials containing JW oil as sole bioactive component. Transparent films were fabricated at gelatin:JW oil ratios of 20:0, 20:1, 20:5 (w/w) designated as JW-0, JW-1, JW-2, respectively, via solution casting. Gas chromatography revealed that JW oil is rich in unsaturated fatty acids, predominantly linoleic and oleic acids, while FTIR confirmed their successful integration into the gelatin matrix through the fatty acid peak at 1743 cm⁻¹. Oil droplets, increasing with oil content was shown by SEM. JW oil improved water durability by reducing water aging by up to 8%. JW oil acted as a plasticizer, raising elongation at break (EAB) from 188% in JW-0 to 231% and 209% in JW-1 and JW-2, respectively. DSC indicated a higher T_max in JW-1 (116 °C) compared to JW-2 (110 °C), evidencing better thermal stability. In conclusion, JW oil can be effectively incorporated into gelatin as a single active component. Specifically, JW-1 formulation achieved an optimal balance between mechanical and structural integrity, flexibility, and thermal stability, underscoring its potential as a cost-effective, bioactive wound dressing material. Full article

Introduction: Chronic wounds and pathologic scars remain a persistent challenge in plastic surgery. Conventional treatments can be costly and inconsistent, prompting interest in regenerative approaches that utilize autologous tissue. Emulsified fat produces nanofat through mechanical processing and contains adipose-derived stem cells, stromal vascular fractions, extracellular matrix proteins, cytokines and growth factors. The purpose of this systematic review is to evaluate the use of autologous nanofat for wound healing and scar management, with emphasis on preparation techniques, treatment indications, and outcomes. Methods: A comprehensive PubMed search with no date restrictions was conducted in January 2026 using MeSH terms and keywords related to nanofat and wound-healing applications. Studies were screened independently by two reviewers using the Rayyan platform. Eligible studies evaluated nanofat for wound healing in human or animal subjects; non-English articles, studies not involving nanofat, editorials, and conference abstracts were excluded. The extracted data included study characteristics, participant numbers, treatment details, indications, adjunct therapies, follow-up duration, outcomes, and complications. Studies were grouped by clinical application, with individual reports included in multiple categories when relevant. Results: The search identified 53 records, of which 22 studies met the inclusion criteria after screening. These included 20 human and two animal studies spanning randomized controlled trials (n = 3), prospective trials (n = 6), retrospective analyses (n = 6), case series (n = 4), and case reports (n = 3). Mechanical emulsification was the predominant autologous nanofat preparation method (91%), often combined with filtration or centrifugation. Clinical indications in human studies were diverse, most commonly including scar treatment (n = 14) (acne, burns, depressed, and post-surgical), followed by chronic wounds (n = 3) and reconstructive applications (n = 3). Nanofat was administered via injection in 86% of studies (n = 19), typically using fine-gauge needles or microcannulas with intradermal or subdermal placement, while three studies used non-injection approaches such as topical, membrane, or dressing-based delivery. Scar or aesthetic parameters, measured using VSS, POSAS, physician grading, photography, pigmentation analysis, or clinical appearance, were evaluated in 73% of studies (n = 16), and all reported improvement in variables such as pigmentation, pliability, thickness, texture, or overall appearance. Wound-healing endpoints were assessed in 36% (n = 8), with 100% (n = 8) demonstrating accelerated healing, improved epithelialization, or defect closure. Patient-reported outcomes, including satisfaction or quality of life, were measured in 32% (n = 7), and all showed improvement. Objective imaging modalities (e.g., 3D imaging, ultrasound, angiography, digital analysis) were used in 23% (n = 5), each confirming structural or physiologic improvement. Histologic or biomolecular analyses were performed in 27% (n = 6) and uniformly demonstrated regenerative changes, such as increased angiogenesis, collagen remodeling, or growth factor expression. Treatment was well tolerated, with 77% of studies (n = 17) reporting minimal or no complications and only transient mild adverse effects, including mild pain, bruising, erythema, and edema. Conclusions: Current evidence suggests that autologous nanofat is a promising regenerative therapy for wound healing and scar modulation. Across diverse clinical applications, nanofat has been associated with improved tissue quality, enhanced healing, and favorable patient-reported outcomes, with minimal complications. The mechanical processing of autologous tissue may also involve fewer regulatory concerns compared with more extensively manipulated cellular products. Full article

With an increased number of chronic wounds and accidents worldwide, the need for advanced wound care approaches has been urgent. In this regard, sprayable hydrogel dressings have emerged as an innovative biomaterial due to their unique rheological properties, minimally invasive operation capabilities, excellent adaptability to irregular surfaces, and in situ rapid gelation. This review focused on elaborating the main materials used to construct sprayable hydrogels, including natural polymers and synthetic polymers, and discussing their respective molecular structures, physicochemical properties, advantages, and challenges in formulation design. This review also explored the properties of sprayable hydrogels, including sprayability, adhesion performance, mechanical strength, moisture absorption, breathability, biocompatibility, and degradability. The mechanisms of their controllable gelation through chemical crosslinking and physical crosslinking strategies were analyzed. Subsequently, the applications of sprayable hydrogels in wound areas, including diabetic wounds, infected wounds, postoperative adhesions, burn wounds, and joint wounds, were comprehensively reviewed. The challenges and future developments in wound healing were clarified to provide valuable references for promoting interdisciplinary research and the clinical translation of sprayable hydrogels. Full article

Wound healing is a complex physiological process involving multiple stages, including hemostasis, inflammation, proliferation, and remodeling, which imposes high demands on the functionality and adaptability of wound repair materials. Hydrogels, as a class of novel materials, have become ideal wound dressings due to their excellent biocompatibility, breathability, and conformability. Sodium alginate-based composite hydrogels offer advantages such as readily available raw materials and mild preparation conditions. They can also endow materials with properties including antibacterial, anti-inflammatory, hemostatic, and pro-angiogenic effects, meeting the application requirements for multifunctional and highly efficient wound dressings. As a result, they have attracted considerable attention in the field of wound repair. This article introduces the preparation methods of physically and chemically crosslinked sodium alginate-based composite hydrogels, as well as the drug release mechanisms from these hydrogels. It elaborates on their applications in wound dressings, discusses key challenges including difficulties in large-scale preparation, high barriers to clinical translation, insufficient long-term in vivo stability, and low integration of intelligent functions, and outlines future research directions in terms of large-scale fabrication, regulatory compliance, long-term safety, and intelligent design. This review aims to provide a theoretical basis for the development of novel sodium alginate-based composite hydrogels for wound dressings and to promote their clinical translation and practical application in this field. Full article

Modern wound care is challenged by the emergence of antibiotic-resistant bacterial strains, causing the need for advanced dressing materials that provide infection control while promoting healing. Although polyacrylamide (PAAm) hydrogels are widely investigated due to their biocompatibility, their lack of intrinsic antibacterial activity and poor mechanical properties restrict their clinical use. To overcome these limitations, this study proposes a natural–synthetic hydrogel that combines PAAm with TEMPO-oxidized cellulose nanofiber (TOCNF) functionalized silver nanoparticles (AgNPs). The synthesis is performed through the polymerization of the synthetic monomer in the presence of the TOCNF–AgNPs, the nanofibrillar cellulose simultaneously serving as a reducing and stabilizing agent for AgNPs, and as a plasticizer for the PAAm network. Morpho-structural analysis of the hybrid precursor (TOCNF–AgNPs) revealed two populations of AgNPs, offering a cumulative effect between rapid bacterial penetration and a prolonged ionic reservoir, while maintaining the stability of the system. The subsequent incorporation of the hybrid into PAAm matrix resulted in tunable swelling kinetics and mechanical properties. Wettability and surface stiffness improve with the increase in hybrid content. The antibacterial effect was confirmed by a colony-counting assay for formulations with higher AgNPs content, exhibiting inhibitory metabolic activity against several pathogenic strains. These results suggest that PAAm/TOCNF–AgNPs (PTA) nanocomposites represent a promising mechanically adaptive candidate for wound-care applications. Full article