Biomedical materials for wound dressing: recent advances and applications

Therapeutic effects of OXY- ExoAloe in diabetic wound injury

Delayed wound healing are common complications for diabetic patients. In light of chronic hypoxia's delay in wound healing, it is hypothesized that providing a better oxygen environment at the wound site will promote diabetic wound healing. OXY-ExoAloe is an innovative and effective therapy prepared from exosome-like vesicles of aloe vera gel, ginger juice and neem fruit sap. A combination of three herbal, oxygen-delivering and medicinally valued plants was standardized to determine if the combination had the desired effect. Interestingly, when we used OXY-ExoAloe at a particular ratio on a diabetic wound, the herbal therapy speeded up wound healing by reducing swelling, and the severity of the wound. Further, our data suggests that OXY-ExoAloe promoted wound healing by increasing wound oxygenation, reducing inflammation, cytokine production, and matrix remodeling. It is also safe and effective, with no reported side effects.

Review on application of herbal extracts in biomacromolecules-based nanofibers as wound dressings and skin tissue engineering

The skin, which covers an area of 2 square meters of an adult human, accounts for about 15 % of the total body weight and is the body's largest organ. It protects internal organs from external physical, chemical, and biological attacks, prevents excess water loss from the body, and plays a role in thermoregulation. The skin is constantly exposed to various damages so that wounds can be acute or chronic. Although wound healing includes hemostasis, inflammatory, proliferation, and remodeling, chronic wounds face different treatment problems due to the prolonged inflammatory phase. Herbal extracts such as Nigella Sativa, curcumin, chamomile, neem, nettle, etc., with varying properties, including antibacterial, antioxidant, anti-inflammatory, antifungal, and anticancer, are used for wound healing. Due to their instability, herbal extracts are loaded in wound dressings to facilitate skin wounds. To promote skin wounds, skin tissue engineering was developed using polymers, bioactive molecules, and biomaterials in wound dressing. Conventional wound dressings, such as bandages, gauzes, and films, can't efficiently respond to wound healing. Adhesion to the wounds can worsen the wound conditions, increase inflammation, and cause pain while removing the scars. Ideal wound dressings have good biocompatibility, moisture retention, appropriate mechanical properties, and non-adherent and proper exudate management. Therefore, by electrospinning for wound healing applications, natural and synthesis polymers are utilized to fabricate nanofibers with high porosity, high surface area, and suitable mechanical and physical properties. This review explains the application of different herbal extracts with different chemical structures in nanofibrous webs used for wound care.

Chitosan microflower-embedded gelatin sponges for advanced wound management and hemostatic applications

The study explored the antimicrobial, antibiofilm, and hemostatic properties of chitosan microflowers (CMF) in sponge form. The main objective was to enhance the preparation of CMF by employing varying quantities of calcium chloride (CaCl2) and tripolyphosphate (TPP). CMF was then combined with gelatin (GE) in different proportions to produce three sponge samples: CMF0@GE, CMF1@GE, and CMF2@GE. The CMF had a morphology like that of a flower and produced surfaces with a porous sponge-like structure. The antibacterial activity, as determined by the zone of inhibition (ZOI), increased with greater doses of CMF. Among the tested samples, CMF2@GE had the greatest activity against Pseudomonas aeruginosa, Klebsiella pneumoniae, Staphylococcus aureus, and Enterococcus faecium. CMF2@GE successfully suppressed biofilm formation, decreased clotting time to an average of 212.67 s, and exhibited excellent biocompatibility by preserving over 90 % viability of human skin fibroblast cells at dosages below 100 μg/mL. The results indicated that gelatin sponges filled with CMF have considerable promise as flexible medical instruments for wound healing and infection control.

Developmental prospects of carrageenan-based wound dressing films: Unveiling techno-functional properties and freeze-drying technology for the development of absorbent films - A review

This review explores the intricate wound healing process, emphasizing the critical role of dressing material selection, particularly for chronic wounds with high exudate levels. The aim is to tailor biodegradable dressings for comprehensive healing, focusing on maximizing moisture retention, a vital element for adequate recovery. Researchers are designing advanced wound dressings that enhance techno-functional and bioactive properties, minimizing healing time and ensuring cost-effective care. The study delves into wound dressing materials, highlighting carrageenan biocomposites superior attributes and potential in advancing wound care. Carrageenan's versatility in various biomedical applications demonstrates its potential for tissue repair, bone regeneration, and drug delivery. Ongoing research explores synergistic effects by combining carrageenan with other novel materials, aiming for complete biocompatibility. As innovative solutions emerge, carrageenan-based wound-healing medical devices are poised for global accessibility, addressing challenges associated with the complex wound-healing process. The exceptional physico-mechanical properties of carrageenan make it well-suited for highly exudating wounds, offering a promising avenue to revolutionize wound care through freeze-drying techniques. This thorough approach to evaluating the wound healing effectiveness of carrageenan-based films, particularly emphasizing the development potential of lyophilized films, has the potential to significantly improve the quality of life for patients receiving wound healing treatments.

Loading of bacterial cellulose dressing with frutalin, a lectin from Artocarpus incisa L

Bacterial cellulose (BC), produced by bacterial fermentation, is a high-purity material. BC can be oxidized (BCOXI), providing aldehyde groups for covalent bonds with drugs. Frutalin (FTL) is a lectin capable of modulating cell proliferation and remodeling, which accelerates wound healing. This study aimed to develop an FTL-incorporated dressing based on BC, and to evaluate its physicochemical properties and biological activity in vitro. An experimental design was employed to maximize FTL loading yield onto the BC and BCOXI, where independent variables were FTL concentration, temperature and immobilization time. BCOXI-FTL 1 (44.96 % ± 1.34) had the highest incorporation yield (IY) at the experimental conditions: 6 h, 5 °C, 20 μg mL-1. The second highest yield was BCOXI-FTL 6 (23.28 % ± 1.43) using 24 h, 5 °C, 100 μg mL-1. Similarly, the same reaction parameters provided higher immobilization yields for native bacterial cellulose: BC-FTL 6 (16.91 % ± 1.05) and BC-FTL 1 (21.71 % ± 1.57). Purified FTL displayed no cytotoxicity to fibroblast cells (<50 μg mL-1 concentration) during 24 h. Furthermore, BCOXI-FTL and BC-FTL were non-cytotoxic during 24 h and stimulated fibroblast migration. BCOXI-FTL demonstrated neutrophil activation in vitro similar to FTL. These promising results indicate that the bacterial cellulose matrices containing FTL at low concentrations, could be used as an innovative biomaterial for developing wound dressings.

Innovative approaches to wound healing: insights into interactive dressings and future directions

The objective of this review is to provide an up-to-date and all-encompassing account of the recent advancements in the domain of interactive wound dressings. Considering the gap between the achieved and desired clinical outcomes with currently available or under-study wound healing therapies, newer more specific options based on the wound type and healing phase are reviewed. Starting from the comprehensive description of the wound healing process, a detailed classification of wound dressings is presented. Subsequently, we present an elaborate and significant discussion describing interactive (unconventional) wound dressings. Latter includes biopolymer-based, bioactive-containing and biosensor-based smart dressings, which are discussed in separate sections together with their applications and limitations. Moreover, recent (2-5 years) clinical trials, patents on unconventional dressings, marketed products, and other information on advanced wound care designs and techniques are discussed. Subsequently, the future research direction is highlighted, describing peptides, proteins, and human amniotic membranes as potential wound dressings. Finally, we conclude that this field needs further development and offers scope for integrating information on the healing process with newer technologies.

Effect of the molar mass of chitosan and film casting solvents on the properties of chitosan films loaded with Mentha spicata essential oil for potential application as wound dressing

Chitosan based films endowed with antibacterial features have witnessed remarkable progress as potential wound dressings. The current study aimed at appraising the effects of the molar mass of chitosan (MM) and the film casting acids on the properties of unplasticized chitosan films and plasticized MSO-embedded chitosan films in order to provide best suited film formulation as a potential candidate for wound dressing application. The prepared films were functionally characterized in terms of their qualitative assessment, thickness, density, swelling behavior, water vapor barrier, mechanical and antibacterial properties. Overall, all chitosan films displayed thickness lower than the human dermis even though thicker and denser films were produced with lactic acid. Assessment of the swelling behavior revealed that only high molar mass (HMM) chitosan films may be regarded as absorbent dressings. Moreover, unplasticized HMM lactate (HMM-LA) films furnished lower stiffness and higher percent strain break as compared to acetate films, due to the plasticizing effect of the remaining lactic acid as alluded by the FTIR analysis. Meanwhile, they provided suitable level of moisture and indicated substantial antibacterial activity against S. aureus and E. coli, the most commonly opportunistic bacteria found in infected skin wound. Plasticized chitosan films doped with MSO were significantly thicker and more permeable to water compared to unplasticized films. Furthermore, MSO significantly potentiate the antibacterial effect of chitosan-based films. Therefore, plasticized HMM-LA/MSO chitosan film flashing good swelling behavior, adequate WVTR and WVP, suitable mechanical properties and antibacterial performances substantiated to be a promising antibacterial dressing material for moderately exuding wounds.

Advances of antimicrobial dressings loaded with antimicrobial agents in infected wounds

Wound healing is a complex process that is critical for maintaining the barrier function of the skin. However, when a large quantity of microorganisms invade damaged skin for an extended period, they can cause local and systemic inflammatory responses. If left untreated, this condition may lead to chronic infected wounds. Infected wounds significantly escalate wound management costs worldwide and impose a substantial burden on patients and healthcare systems. Recent clinical trial results suggest that the utilization of effective antimicrobial wound dressing could represent the simplest and most cost-effective strategy for treating infected wounds, but there has hitherto been no comprehensive evaluation reported on the efficacy of antimicrobial wound dressings in promoting wound healing. Therefore, this review aims to systematically summarize the various types of antimicrobial wound dressings and the current research on antimicrobial agents, thereby providing new insights for the innovative treatment of infected wounds.

Functional network copolymeric hydrogels derived from moringa gum: Physiochemical, drug delivery and biomedical properties

The article explores the synthesis of network hydrogels derived from moringa gum (MG) through a grafting reaction with poly (vinylsulfonic acid) and carbopol. These hydrogels are designed for use in drug delivery (DD) and wound hydrogels dressing (HYDR) applications. The copolymers were characterized by FESEM, EDX, AFM, FTIR, 13C NMR, XRD and DSC. Tetracycline release from hydrogel occurred gradually with a non-Fickian diffusion and was best described by the Hixson-Crowell kinetic model in artificial wound fluid. The HYDR demonstrated compatibility with blood, exhibited antioxidant properties and possessed tensile strength, in addition to their mucoadhesive characteristics. The copolymer dressings absorbed approximately 7 g of simulated fluid. The copolymers exhibited significant antioxidant activity, measuring at 84 % free radicals scavenging, during DPPH assay. These dressings demonstrated permeability to H2O and O2,. The hydrogel alone did not reveal antibacterial activities; however, when combined with antibiotic drug tetracycline, the dressings revealed notable antibacterial activities against Staphylococcus aureus, Pseudomonas aeruginosa and Escherichia coli. The observed biomedical properties suggested that these hydrogels could serve as promising materials for drug delivery HYDR applications.

Films based on TEMPO-oxidized chitosan nanoparticles: Obtaining and potential application as wound dressings

A series of novel films based on TEMPO-oxidized chitosan nanoparticles were prepared by casting method. Fourier transform infrared spectroscopy (FTIR) was employed to ascertain the chemical structure of TEMPO-oxidized chitosan. The surface morphology of the TEMPO-oxidized chitosan nanoparticles was analyzed by atomic force microscopy (AFM). The physicochemical (area density, thickness, iodine sorption, roughness), functional (moisture sorption, liquid absorption capacity, weight loss upon contact with the liquid, and water vapor transmission rate), antibacterial, and antioxidant properties of films based on TEMPO-oxidized chitosan nanoparticles were also investigated. The physicochemical properties of the films varied widely: area density ranged from 77.83 ± 0.06 to184.46 ± 0.05 mg/cm2, thickness varied between 80.5 ± 1.6 and 200.5 ± 1.6 μm, iodine sorption spanned from 333.7 ± 2.1 to166.4 ± 2.2 mg I2/g, and roughness ranged from 4.1 ± 0.2 to 5.6 ± 0.3 nm. Similarly, the functional properties also varied significantly: moisture sorption ranged from 4.76 ± 0.03 to 9.62 ± 0.11 %, liquid absorption capacity was between 129.04 ± 0.24 and 159.33 ± 0.73 % after 24 h, weight loss upon contact with the liquid varied between 31.06 ± 0.35 and 45.88 ± 0.58 % after 24 h and water vapor transmission rate ranged from 1220.10 ± 2.91to1407.77 ± 5.22 g/m2 day. Despite the wide variations in physicochemical and functional properties, all films showed maximum bacterial reduction of Staphylococcus aureus and Escherichia coli, although they exhibited low antioxidant activity. The results suggest that the films could be effectively utilized as antibacterial wound dressings.

The role of glycerol in manufacturing freeze-dried chitosan and cellulose foams for mechanically stable scaffolds in skin tissue engineering

Various strategies have extensively explored enhancing the physical and biological properties of chitosan and cellulose scaffolds for skin tissue engineering. This study presents a straightforward method involving the addition of glycerol into highly porous structures of two polysaccharide complexes: chitosan/carboxymethyl cellulose (Chit/CMC) and chitosan/oxidized cellulose (Chit/OC); during a one-step freeze-drying process. Adding glycerol, especially to Chit/CMC, significantly increased stability, prevented degradation, and improved mechanical strength by nearly 50%. Importantly, after 21 days of incubation in enzymatic medium Chit/CMC scaffold has almost completely decomposed, while foams reinforced with glycerol exhibited only 40% mass loss. It is possible due to differences in multivalent cations and polymer chain contraction, resulting in varied hydrogen bonding and, consequently, distinct physicochemical outcomes. Additionally, the scaffolds with glycerol improved the cellular activities resulting in over 40% higher proliferation of fibroblast after 21 days of incubation. It was achieved by imparting water resistance to the highly absorbent material and aiding in achieving a balance between hydrophilic and hydrophobic properties. This study clearly indicates the possible elimination of additional crosslinkers and multiple fabrication steps that can reduce the cost of scaffold production for skin tissue engineering applications while tailoring mechanical strength and degradation.

Mechanism and application of fibrous proteins in diabetic wound healing: a literature review

Diabetic wounds are more complex than normal chronic wounds because of factors such as hypoxia, reduced local angiogenesis, and prolonged inflammation phase. Fibrous proteins, including collagen, fibrin, laminin, fibronectin, elastin etc., possess excellent inherent properties that make them highly advantageous in the area of wound healing. Accumulating evidence suggests that they contribute to the healing process of diabetic wounds by facilitating the repair and remodel of extracellular matrix, stimulating the development of vascular and granulation tissue, and so on. However, there is currently a lack of a comprehensive review of the application of these proteins in diabetes wounds. An overview of fibrous protein characteristics and the alterations linked to diabetic wounds is given in this article's initial section. Next is a summary of the advanced applications of fibrous proteins in the last five years, including acellular dermal matrix, hydrogel, foam, scaffold, and electrospun nanofibrous membrane. These dressings have the ability to actively promote healing in addition to just covering wounds compared to traditional wound dressings like gauze or bandage. Research on fibrous proteins and their role in diabetic wound healing may result in novel therapeutic modalities that lower the incidence of diabetic wounds and thereby enhance the health of diabetic patients.

Antimicrobial peptide-fibrin glue mixture for treatment of methicillin-resistant Staphylococcus aureus-infected wounds

Aim: This study was conducted to investigate the effect of fibrin glue-CM11 antibacterial peptide mixture (FG-P) on the healing of infected wounds in vivo. Materials & methods: We formulated a mixture of FG-P and evaluated its antimicrobial activity in vitro against multidrug-resistant (MDR) bacteria involved in wound infection as well as its healing effect on wound infected by methicillin-resistant S. aureus (MRSA) in vivo. Results: The peptide had an MIC of 8 μg/ml against all bacteria isolates. Growth inhibition zones were evident for FG-P compared with FG. The in vivo study showed that the FG-P could be significantly effective in healing the MRSA-infected wound. Conclusion: The use of FG-P mixture is a very suitable option for treating infected wounds.

A Double Network Composite Hydrogel with Self-Regulating Cu2+/Luteolin Release and Mechanical Modulation for Enhanced Wound Healing

Designing adaptive and smart hydrogel wound dressings to meet specific needs across different stages of wound healing is crucial. Here, we present a composite hydrogel, GSC/PBE@Lut, that offers self-regulating release of cupric ions and luteolin and modulates mechanical properties to promote chronic wound healing. The double network hydrogel, GSC, is fabricated through photo-cross-linking of gelatin methacrylate, followed by Cu2+-alginate coordination cross-linking. On one hand, GSC allows for rapid Cu2+ release to eliminate bacteria in the acidic pH environment during inflammation and reduces the hydrogel's mechanical strength to minimize tissue trauma during early dressing changes. On the other hand, GSC enables slow Cu2+ release during the proliferation stage, promoting angiogenesis and biocompatibility. Furthermore, the inclusion of pH- and reactive oxygen species (ROS)-responsive luteolin nanoparticles (PBE@Lut) in the hydrogel matrix allows for controlled release of luteolin, offering antioxidant and anti-inflammatory effects and promoting anti-inflammatory macrophage polarization. In a murine model of Staphylococcus aureus infected wounds, GSC/PBE@Lut demonstrates exceptional therapeutic benefits in antibacterial, anti-inflammatory, angiogenic, and tissue regeneration. Overall, our results suggest that smart hydrogels with controlled bioactive agent release and mechanical modulation present a promising solution for treating chronic wounds.

Development and Investigation of an Innovative 3D Biohybrid Based on Collagen and Silk Sericin Enriched with Flavonoids for Potential Wound Healing Applications

Skin tissue injuries necessitate particular care due to associated complex healing mechanisms. Current investigations in the domain of tissue engineering and regenerative medicine are focused on obtaining novel scaffolds adapted as potential delivery systems to restore lost tissue functions and properties. In this study, we describe the fabrication and evaluation of a novel 3D scaffold structure based on collagen and silk sericin (CollSS) enriched with microcapsules containing natural compounds, curcumin (C), and/or quercetin (Q). These 3D composites were characterized by FT-IR spectroscopy, water uptake, in vitro collagenase degradation, and SEM microscopy. Furthermore, they were biologically evaluated in terms of biocompatibility, cell adhesion, anti-inflammatory, and antioxidant properties. All tested materials indicated an overall suitable biocompatibility, with the best results obtained for the one containing both flavonoids. This study suggests the cumulative beneficial effect of C and Q, encapsulated in the same composite, as a potential non-invasive therapeutic strategy for skin tissue regeneration in patients suffering from chronic wounds.

Albumin-Based Hydrogel Films Covalently Cross-Linked with Oxidized Gellan with Encapsulated Curcumin for Biomedical Applications

Bovine serum albumin (BSA) hydrogels are non-immunogenic, low-cost, biocompatible, and biodegradable. In order to avoid toxic cross-linking agents, gellan was oxidized with NaIO4 to obtain new functional groups like dialdehydes for protein-based hydrogel cross-linking. The formed dialdehyde groups were highlighted with FT-IR and NMR spectroscopy. This paper aims to investigate hydrogel films for biomedical applications obtained by cross-linking BSA with oxidized gellan (OxG) containing immobilized β-cyclodextrin-curcumin inclusion complex (β-CD-Curc) The β-CD-Curc improved the bioavailability and solubility of Curc and was prepared at a molar ratio of 2:1. The film's structure and morphology were evaluated using FT-IR spectroscopy and SEM. The swelling degree (Q%) values of hydrogel films depend on hydrophilicity and pH, with higher values at pH = 7.4. Additionally, the conversion index of -NH2 groups into Schiff bases increases with an increase in OxG amount. The polymeric matrix provides protection for Curc, is non-cytotoxic, and enhances antioxidant activity. At pH = 5.5, the skin permeability and release efficiency of encapsulated curcumin were higher than at pH = 7.4 because of the interaction of free aldehyde and carboxylic groups from hydrogels with amine groups from proteins present in the skin membrane, resulting in a better film adhesion and more efficient curcumin release.

Biomineral-Based Composite Materials in Regenerative Medicine

Regenerative medicine aims to address substantial defects by amplifying the body's natural regenerative abilities and preserving the health of tissues and organs. To achieve these goals, materials that can provide the spatial and biological support for cell proliferation and differentiation, as well as the micro-environment essential for the intended tissue, are needed. Scaffolds such as polymers and metallic materials provide three-dimensional structures for cells to attach to and grow in defects. These materials have limitations in terms of mechanical properties or biocompatibility. In contrast, biominerals are formed by living organisms through biomineralization, which also includes minerals created by replicating this process. Incorporating biominerals into conventional materials allows for enhanced strength, durability, and biocompatibility. Specifically, biominerals can improve the bond between the implant and tissue by mimicking the micro-environment. This enhances cell differentiation and tissue regeneration. Furthermore, biomineral composites have wound healing and antimicrobial properties, which can aid in wound repair. Additionally, biominerals can be engineered as drug carriers, which can efficiently deliver drugs to their intended targets, minimizing side effects and increasing therapeutic efficacy. This article examines the role of biominerals and their composite materials in regenerative medicine applications and discusses their properties, synthesis methods, and potential uses.

A bacterial cellulose/polyvinyl alcohol/nitro graphene oxide double layer network hydrogel efficiency antibacterial and promotes wound healing

In this study, graphene oxide (GO) was chemically modified utilizing concentrated nitric acid to produce a nitrated graphene oxide derivative (NGO) with enhanced oxidation level, improved dispersibility, and increased antibacterial activity. A double-layer composite hydrogel material (BC/PVA/NGO) with a core-shell structure was fabricated by utilizing bacterial cellulose (BC) and polyvinyl alcohol (PVA) binary composite hydrogel scaffold as the inner network template, and hydrophilic polymer (PVA) loaded with antibacterial material (NGO) as the outer network. The fabrication process involved physical crosslinking based on repeated freezing and thawing. The resulting BC/PVA/NGO hydrogel exhibited a porous structure, favorable mechanical properties, antibacterial efficacy, and biocompatibility. Subsequently, the performance of BC/PVA/NGO hydrogel in promoting wound healing was evaluated using a mouse skin injury model. The findings demonstrated that the BC/PVA/NGO hydrogel treatment group facilitated improved wound healing in the mouse skin injury model compared to the control group and the BC/PVA group. This enhanced wound healing capability was attributed primarily to the excellent antibacterial and tissue repair properties of the BC/PVA/NGO hydrogel.

Metal-ion-controlled hydrogel dressing with enhanced adhesive and antibacterial properties for accelerated wound healing

In order to improve the wound repair environment, this research has successfully developed a new multifunctional hydrogel dressing, which has strong adaptability and can accelerate wound healing. Pioneering the development of metal-ion-controlled hydrogel dressings, this research integrates dopamine and imidazole double crosslinked networks with metal-ion coordination. The resulting hydrogel dressing exhibits a notable antibacterial effect and exceptional mechanical properties, withstanding pressures of up to 12 kPa, tensions of 25 kPa, and maintaining skin adhesion at 6 kPa. Furthermore, the dressing can self-heal within only 7-8 s post-injection. Impressively, the hydrogel achieves complete biodegradation within a short timeframe (37 h). Notably, the use of various metal ions facilitates painless peeling during the degradation period, perfectly aligning with the requirements of an ideal wound dressing. This study has made significant progress in the fields of trauma repair and materials, providing strong solutions for dealing with harsh post-traumatic environments.

Preparation and characterization of PVA/chitosan nanofibers loaded with Dragon's blood or poly helixan as wound dressings

Nanofibers have been investigated in regenerative medicine. Dragon's blood (DB)- and poly helixan PF (PHPF) are natural materials used in cosmetics. Herein, we generated DB- and PHPF-loaded polyvinyl alcohol/chitosan (PVA/CS/DB and PVA/CS/PHPF, respectively) nanofibers. PVA/CS/DB and PVA/CS/PHPF nanofibers had an average diameter of 547.5 ± 17.13 and 521 ± 24.67 nm, respectively as assessed by SEM, and a degradation rate of 43.1 and 47.6 % after 14 days, respectively. PVA/CS/DB and PVA/CS/PHPF nanofibers had a hemolysis rate of 0.10 and 0.39 %, respectively, and a water vapor transmission rate of ∼2200 g.m-2.day-1. These nanofibers exhibited favorable antimicrobial activity against Escherichia coli, Pseudomonas aeruginosa, Staphylococcus aureus, and Bacillus subtilis in vitro. PVA/CS/DB and PVA/CS/PHPF nanofibers demonstrated a sustained release of 77.91 and 76.55 % over 72 h. PVA/CS/DB and PVA/CS/PHPF nanofibers had a high rate of cytocompatibility and significantly improved the viability of NIH/3T3 cells as compared with free drugs or unloaded nanofibers. Histological inspection via H&E and Verhoeff's staining demonstrated PVA/CS/DB and PVA/CS/PHPF nanofibers enhanced the wound healing and damaged tissue recovery of unsplinted wound models by promoting epithelial layer formation, collagen deposition, and enhancing the presence of fibroblasts. Conclusively, PVA/CS/DB and PVA/CS/PHPF can be introduced as potential wound dressing candidates with favorable properties.

Advanced Dressings for Chronic Wound Management

Wound healing, particularly for chronic wounds, presents a considerable difficulty due to differences in biochemical and cellular processes that occur in different types of wounds. Recent technological breakthroughs have notably advanced the understanding of diagnostic and therapeutic approaches to wound healing. The evolution in wound care has seen a transition from traditional textile dressings to a variety of advanced alternatives, including self-healing hydrogels, hydrofibers, foams, hydrocolloids, environment responsive dressings, growth factor-based therapy, bioengineered skin substitutes, and stem cell and gene therapy. Technological advancements, such as 3D printing and electronic skin (e-skin) therapy, contribute to the customization of wound healing. Despite these advancements, effectively managing chronic wounds remains challenging. This necessitates the development of treatments that consider performance, risk-benefit balance, and cost-effectiveness. This review discusses innovative strategies for the healing of chronic wounds. Incorporating biomarkers into advanced dressings, coupled with corresponding biosensors and drug delivery formulations, enables the theranostic approach to the treatment of chronic wounds. Furthermore, integrating advanced dressings with power sources and user interfaces like near-field communication, radio frequency identification, and Bluetooth enhances real-time monitoring and on-demand drug delivery. It also provides a thorough evaluation of the advantages, patient compliance, costs, and durability of advanced dressings, emphasizing smart formulations and their preparation methods.

Design and Synthesis of Biomedical Polymer Materials

Due to their biocompatibility and non-toxic nature, biomedical polymer materials have found widespread applications and significantly propelled the progress of the biomedical field [...].

Biomimetic Materials for Skin Tissue Regeneration and Electronic Skin

Biomimetic materials have become a promising alternative in the field of tissue engineering and regenerative medicine to address critical challenges in wound healing and skin regeneration. Skin-mimetic materials have enormous potential to improve wound healing outcomes and enable innovative diagnostic and sensor applications. Human skin, with its complex structure and diverse functions, serves as an excellent model for designing biomaterials. Creating effective wound coverings requires mimicking the unique extracellular matrix composition, mechanical properties, and biochemical cues. Additionally, integrating electronic functionality into these materials presents exciting possibilities for real-time monitoring, diagnostics, and personalized healthcare. This review examines biomimetic skin materials and their role in regenerative wound healing, as well as their integration with electronic skin technologies. It discusses recent advances, challenges, and future directions in this rapidly evolving field.

An injectable sequential dual-crosslinking catechol-functionalized hyaluronic acid hydrogel for enhanced regeneration of full-thickness burn injury

Severe burn injuries with massive dermal loss are often underestimated despite their significant impact on morbidity and mortality. Resembling the natural extracellular matrix (ECM), hyaluronic acid (HA)-based dressings have been extensively explored as suitable candidates for burn wound treatment. However, native HA hydrogel's limitations, such as low mechanical strength, rapid degradation, and uncontrollable drug delivery, hinder its efficacy, especially for full-thickness burns requiring injectable hydrogels with robust antibacterial and angiogenic capabilities. Herein, we present a novel multifunctional sequential dual-curing hydrogel system, combining hyperbranched poly(DMA-DMAPMA-PEGDA) (DDP) polymer with thiolated hyaluronic acid (HA-SH). The DDP copolymer, featuring multi-vinyls and catechol functionalities, facilitates two curing reactions taking place sequentially with HA-SH under physiological conditions, balancing convenient injection with the mechanical strength essential for effective wound management. Furthermore, the resulting DDP/HA hydrogels demonstrate enhanced therapeutic attributes, including intrinsic angiogenic and antimicrobial effects, setting them as promising dressing options for deep burn wound therapy.

Multihydrogen Bond Modulated Polyzwitterionic Removable Adhesive Hydrogel with Antibacterial and Hemostatic Function for Wound Healing

Wound management is a major challenge worldwide, placing a huge financial burden on the government of every nation. Wound dressings that can protect wounds, accelerate healing, prevent infection, and avoid secondary damage continue to be a major focus of research in the health care and clinical communities. Herein, a novel zwitterionic polymer (LST) hydrogel incorporated with [2-(methacryloyloxy) ethyl] dimethyl-(3-sulfopropyl) ammonium hydroxide (SBMA), mussel-inspired N-[tris(hydroxymethyl)methyl] acrylamide (THMA), and lithium magnesium salt was prepared for functional wound dressings. The incorporation of the THMA monomer containing three hydroxyl groups gives the hydrogel suitable adhesion properties (∼6.0 KPa). This allows the LST zwitterionic hydrogels to bind well to the skin, which not only protects the wound and ensures its therapeutic efficacy but also allows for painless removal and reduced patient pain. Zwitterionic sulfobetaine units of SBMA provide antimicrobial and mechanical properties. The chemical structure and microscopic morphology of LST zwitterionic hydrogels were systematically studied, along with their swelling ratio, adhesion, and mechanical properties. The results showed that the LST zwitterionic hydrogels had a uniform and compact porous structure with the highest swelling and mechanical strain of 1607% and 1068.74%, respectively. The antibacterial rate of LST zwitterionic hydrogels was as high as 99.49%, and the hemostatic effect was about 1.5 times that of the commercial gelatin hemostatic sponges group. In further studies, a full-thickness mouse skin model was selected to evaluate the wound healing performance. Wounds covered by LST zwitterionic hydrogels had a complete epithelial reformation and new connective tissue, and its vascular regenerative capacity was increased to about 2.4 times that of the commercial group, and the wound could completely heal within 12-13 days. This study provides significant advances in the design and construction of multifunctional zwitterionic hydrogel adhesives and wound dressings.

Recent advances in harnessing biological macromolecules for wound management: A review

Wound dressings (WDs) are an essential component of wound management and serve as an artificial barrier to isolate the injured site from the external environment, thereby helping to prevent exogenous infections and supporting healing. However, maintaining a moist wound environment, providing protection from infection, good biocompatibility, and allowing for gas exchange, remain a challenge in device design. Functional wound dressings (FWDs) prepared from hybrid biological macromolecule-based materials can enhance efficacy of these systems for skin wound management. This review aims to provide an overview of the state-of-the-art FWDs within the field of wound management, with a specific focus on hybrid biomaterials, techniques, and applications developed over the past five years. In addition, we highlight the incorporation of biological macromolecules in WDs, the emergence of smart WDs, and discuss the existing challenges and future prospects for the development of advanced WDs.

Pharmaceutical Applications of Biomass Polymers: Review of Current Research and Perspectives

Polymers derived from natural biomass have emerged as a valuable resource in the field of biomedicine due to their versatility. Polysaccharides, peptides, proteins, and lignin have demonstrated promising results in various applications, including drug delivery design. However, several challenges need to be addressed to realize the full potential of these polymers. The current paper provides a comprehensive overview of the latest research and perspectives in this area, with a particular focus on developing effective methods and efficient drug delivery systems. This review aims to offer insights into the opportunities and challenges associated with the use of natural polymers in biomedicine and to provide a roadmap for future research in this field.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

Carboxymethyl cellulose-agarose hydrogel in poly(3-hydroxybutyrate-co-3-hydroxyvalerate) nanofibers: A novel tissue engineered skin graft

Healing chronic and critical-sized full-thickness wounds is a major challenge in the healthcare sector. Scaffolds prepared using electrospinning and hydrogels serve as effective treatment options for wound healing by mimicking the native skin microenvironment. Combining synthetic nanofibers with tunable hydrogel properties can effectively overcome limitations in skin scaffolds made only with nanofibers or hydrogels. In this study, a biocompatible hybrid scaffold was developed for wound healing applications using poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) nanofibers embedded with hydrogel made of 2 % carboxymethyl cellulose (CMC) blended with 1 % agarose. Hybrid scaffolds, characterized for surface morphology, swellability, porosity, and degradation, were found to be suitable for wound healing. Furthermore, the incorporation of CMC-agarose hydrogel into nanofibers significantly enhanced their mechanical strength compared to PHBV nanofibers alone (p < 0.05). Extract cytotoxicity and direct cytotoxicity tests showed that the hybrid scaffolds developed in this study are cytocompatible (>75 % viability). Furthermore, human adult dermal fibroblasts (HDFa) and human adult immortalized keratinocytes (HaCaT) adhesion, viability, and proliferation studies revealed that the hybrid scaffolds exhibited a significant increase in cell proliferation over time, similar to PHBV nanofibers. Finally, the developed hybrid scaffolds were evaluated in rat full-thickness wounds, demonstrating their ability to promote full-thickness wound healing with reepithelialization and epidermis closure.

A tough, antibacterial and antioxidant hydrogel dressing accelerates wound healing and suppresses hypertrophic scar formation in infected wounds

Wound management is an important issue that places enormous pressure on the physical and mental health of patients, especially in cases of infection, where the increased inflammatory response could lead to severe hypertrophic scars (HSs). In this study, a hydrogel dressing was developed by combining the high strength and toughness, swelling resistance, antibacterial and antioxidant capabilities. The hydrogel matrix was composed of a double network of polyvinyl alcohol (PVA) and agarose with excellent mechanical properties. Hyperbranched polylysine (HBPL), a highly effective antibacterial cationic polymer, and tannic acid (TA), a strong antioxidant molecule, were added to the hydrogel as functional components. Examination of antibacterial and antioxidant properties of the hydrogel confirmed the full play of the efficacy of HBPL and TA. In the in vivo studies of methicillin-resistant Staphylococcus aureus (MRSA) infection, the hydrogel had shown obvious promotion of wound healing, and more profoundly, significant suppression of scar formation. Due to the common raw materials and simple preparation methods, this hydrogel can be mass produced and used for accelerating wound healing while preventing HSs in infected wounds.

Film dressings from Thai mango seed kernel extracts versus nanocrystalline silver dressings in antibacterial properties

Introduction: The extract from the Mango Seed Kernel (MSK) has been documented to exhibit antibacterial activity against Gram-positive and Gram-negative bacteria, including Staphylococcus aureus and Pseudomonas aeruginosa. This suggests that biomaterials containing MSK extract could be a viable alternative to conventional wound treatments, such as nanocrystalline silver dressings. Despite this potential, there is a notable gap in the literature regarding comparing the antibacterial effectiveness of MSK film dressings with nanocrystalline silver dressings. This study aimed to develop film dressings containing MSK extract and evaluate their antibacterial properties compared to nanocrystalline silver dressings. Additionally, the study aimed to assess other vital physical properties of these dressings critical for effective wound care. Materials and methods: We prepared MSK film dressings from two cultivars of mango from Thailand, 'Chokanan' and 'Namdokmai'. The inhibition-zone method was employed to determine the antibacterial property. The morphology and chemical characterization of the prepared MSK film dressings were examined with scanning electron microscopy (SEM) and Fourier-Transform Infrared Spectroscopy (FTIR), respectively. The absorption of pseudo-wound exudate and water vapor transmission rate (WVTR) of film dressings were evaluated. Results: The results showed that 40% of MSKC film dressing had the highest inhibition zone (20.00 ± 0.00 mm against S. aureus and 17.00 ± 1.00 mm against P. aeruginosa) and 20%, 30%, and 40% of MSKC and MSKN film dressings had inhibition zones similar to nanocrystalline silver dressing for both S. aureus and P. aeruginosa (p > 0.05). In addition, all concentrations of the MSK film dressings had low absorption capacity, and Chokanan MSK (MSKC) film dressings had a higher WVTR than Namdokmai MSK (MSKN) film dressings. Conclusion: 20%, 30%, and 40% of MSK film dressing is nearly as effective as nanocrystalline silver dressing. Therefore, it has the potential to be an alternative antibacterial dressing and is suitable for wounds with low exudate levels.

Scrutinizing the effect of rGO-cuttlefish bone hydroxyapatite composite infused carrageenan membrane towards wound reconstruction

Carrageenan is an emerging biopolymer for wound healing and regenerative applications. In this study, reduced graphene oxide (rGO) and hydroxyapatite (HAp) nano-composites infused carrageenan bioactive membrane was fabricated. Here, hydroxyapatite was synthesized from cuttlefish bone (CF-HAp) and its properties were compared with that of chemically synthesized HAp. Crystalline Ca5(PO4)3(OH) and Ca3(PO4)2) phases were obtained in cuttlefish bone derived HAp. Reduced graphene oxide was synthesized and composites were prepared with chemical HAp and CF-HAp. FT-IR spectral analysis showed the imprints of hydroxyapatite on the membrane and also nano-structured particles were evident through morphological estimations that confirm the distribution of nano-particles on the carrageenan membrane. Nano-particulates infused carrageenan membrane showed the maximum tensile strength, in which graphene incorporated carrageenan bioactive membrane showed highest stability of 15.26 MPa. The contact angle of chemical HAp infused carrageenan membrane (CAR-HAp) showed more hydrophilic in nature (48.63° ± 7.47°) compared to control (61.77° ± 1.28°). Bio-compatibility features enunciate the optimal compatibility of fabricated bioactive membrane with fibroblast cell line; simultaneously, CAR-rGO-CF-HAp showed tremendous wound healing behavior with zebrafish model. Hence, fabricated bioactive membrane with the infusion of rGO- hydroxyapatite derived from cuttlefish bone was found to be a versatile biopolymer membrane for wound healing application.

Oncological Surgical Wound Care: A Comparison of Theruptor NXT Non-adherent Dressing and the Current Standard of Care

Background Oncological surgeries pose an elevated risk of surgical site infections (SSIs) due to their complexity and various associated treatments, impacting patient outcomes and healthcare costs. This has prompted a focus on advanced wound dressings that provide microbial protection, exudate absorption, and improved product performance, enhancing patient satisfaction. Our study aimed to compare the efficacy and safety of Theruptor NXT with the current standard of care (SOC) practice involving cotton/povidone/micropore dressings in the postoperative wound management of oncological surgeries. Methodology A total of 102 patients who underwent oncological surgeries in the Department of Surgical Oncology, Vydehi Institute of Medical Sciences and Research Centre, Bengaluru, India between May and September 2023 were randomized to Theruptor NXT and SOC dressing groups (51 patients each). The incidence of SSIs, wound pain score, cosmetic appearance of the wound, and adverse events were assessed in the two groups at various intervals, i.e., post-surgery day 2 ± 1, day of discharge, and post-surgery day 30 ± 7. Further, the subject satisfaction and product usage were evaluated on post-surgery day 2 ± 1. Results The baseline characteristics were found to be comparable in both groups, i.e., Theruptor NXT and SOC groups. Further, the SSI rates, scar outcomes, and physiological parameters were also similar between the Theruptor NXT and SOC groups, indicating a similar safety profile of both dressings (p > 0.05). However, the product usage assessment revealed statistically significant differences, favoring Theruptor NXT in terms of superior ease of application, stretchability, exudate management, breathability, and non-adherence properties (p < 0.05). Conclusions Our findings suggest that Theruptor NXT wound dressing is a promising, effective, and user-friendly alternative to SOC wound dressing in diverse clinical settings.

Highly Absorbent Egg White/Carbomer-940 Hydrofilm as a Potential Diabetic Wound Dressing

Diabetic foot ulcer (DFU) is the most critical problem in diabetic patients. Managing exudate in this kind of wound presents significant challenges in clinics. Advanced wound dressings serve as the most effective approach to managing DFU. Herein, a highly absorbent hydrofilm is presented through a combination of egg white (EW) and Carbomer-940, benefiting from the bioactivity of the EW component and superabsorption capacity of Carbomer-940. The crystallinity of samples rises due to the presence of Carbomer-940. Regarding the high water absorption capacity of Carbomer-940, the swelling ratio and water-holding capacity of samples are also improved via its incorporation of up to 1005%. In contrast, the transmission of water vapor and in vitro degradation rate decreases as Carbomer-940 powers the crystallinity of hydrofilms. Carbomer-940 incorporation in the EW structure accelerates protein release during the time, while this acceleration is partially compensated by the crystallization effect. The cell viability assay demonstrates no toxicity as well as high human foreskin fibroblast cell proliferation for the hybrid hydrofilm sample, where the cell migration is positively affected in the presence of the bioactive components extracted from the dressing. Taken together, the optimized hybrid hydrofilm could be suggested as a promising wound dressing for managing DFUs.

Fabrication of a core-shell nanofibrous wound dressing with an antioxidant effect on skin injury

Oxidative stress is one of the obstacles preventing wound regeneration, especially for chronic wounds. Herein, designing a wound dressing with an anti-oxidant function holds great appeal for enhancing wound regeneration. In this study, a biocompatible and degradable nanofiber with a core-shell structure was fabricated via coaxial electrospinning, in which polycaprolactone (PCL) was applied as the core structure, while the shell was composed of a mixture of silk fibroin (SF) and tocopherol acetate (TA). The electrospun PST nanofibers were proven to have a network structure with significantly enhanced mechanical properties. The PSTs exhibited a diameter distribution with an average of 321 ± 134 nm, and the water contact angle of their surface is 124 ± 2°. The PSTs also exhibited good tissue compatibility, which can promote the adhesion and proliferation of L929 cells. Besides, the dissolution of silk fibroin encourages the release of TA, which could play a synergistic effect and regulate the oxidative stress effect in the damaged area, for it promotes the adhesion and proliferation of skin fibroblasts (L929), reduces the cytotoxicity of hydrogen peroxide to cells, and lowers the level of reactive oxygen species. The animal experiment indicated that the PSTs would promote the reconstruction of skin. These nanofibers are expected to repair skin ulcers related to diabetes.

Recent Developments in 3D-(Bio)printed Hydrogels as Wound Dressings

Wound healing is a physiological process occurring after the onset of a skin lesion aiming to reconstruct the dermal barrier between the external environment and the body. Depending on the nature and duration of the healing process, wounds are classified as acute (e.g., trauma, surgical wounds) and chronic (e.g., diabetic ulcers) wounds. The latter take several months to heal or do not heal (non-healing chronic wounds), are usually prone to microbial infection and represent an important source of morbidity since they affect millions of people worldwide. Typical wound treatments comprise surgical (e.g., debridement, skin grafts/flaps) and non-surgical (e.g., topical formulations, wound dressings) methods. Modern experimental approaches include among others three dimensional (3D)-(bio)printed wound dressings. The present paper reviews recently developed 3D (bio)printed hydrogels for wound healing applications, especially focusing on the results of their in vitro and in vivo assessment. The advanced hydrogel constructs were printed using different types of bioinks (e.g., natural and/or synthetic polymers and their mixtures with biological materials) and printing methods (e.g., extrusion, digital light processing, coaxial microfluidic bioprinting, etc.) and incorporated various bioactive agents (e.g., growth factors, antibiotics, antibacterial agents, nanoparticles, etc.) and/or cells (e.g., dermal fibroblasts, keratinocytes, mesenchymal stem cells, endothelial cells, etc.).

Development of nanocomposites based on chitosan/reduced graphene oxide for wound healing application

Nanocomposites containing different effective materials have various effects, such as antioxidant, and anti-inflammatory activity, which are desirable for wound dressing. Herein, nanocomposites based on chitosan/reduced graphene oxide (CS/rGO) containing curcumin (CS/rGO/Cur), curcumin and papain (CS/rGO/Cur/Pa), curcumin, papain, and collagen peptide (CS/rGO/CP/Cur/Pa), prepared using ionic gelation method and characterized by Fourier Transform Infrared (FTIR), Differential Light Scattering (DLS), X-ray diffraction (XRD), and Scanning Electron Microscope (SEM). Subsequently, the nanocomposite's potential for wound healing was studied through parameters such as porosity, swelling, degradability, anti-inflammatory, antioxidant, antibacterial, cell viability, and in-vivo. The results of FTIR, XRD, SEM, and DLS showed that the nanocomposites synthesized properly with an almost spherical morphology, an average diameter of below 100 nm (mostly 40-85 nm), and a hydrodynamic diameter of 455-616 nm. The various tests demonstrated the nanocomposite's effectiveness in wound healing. The results showed that CS/rGO/CP/Cur/Pa increased the anti-inflammatory and cell viability up to 99.7 % and 395 %, respectively, which is higher than others. Animal tests on rats showed that CS/rGO/CP/Cur/Pa accelerated the wound healing rate up to 70 %. In conclusion, the results showed that the nanocomposites based on CS/rGO significantly improve wound healing, and the presence of collagen peptides boost their wound healing potency.

In Situ Formation of Hydrogel Wound Dressing Based on Carboxymethyl Chitin/Tannic Acid for Promoting Skin Wound Healing

Triggering the healing process of drug-resistant bacteria-infected wounds has attracted great attention due to global morbidity that may induce gangrene, amputation, and even death. Here, a chitin derivative, carboxymethyl chitosan (CMC), tannic acid (TA), and Cu2+ were used for hydrogel engineering. Using sodium bicarbonate as the neutralizer and reductant, hydrogen bonds between CMC and TA and in situ Cu(OH)2 generation via ion coordination force between Cu2+ and TA facilitated the synthesis of CMC/TA/Cu hydrogel. Cu2+ and TA release, cytotoxicity, in vitro cell migration, angiogenesis, and antidrug-resistant bacteria were measured. Besides, wound closure was evaluated in vivo using the methicillin-resistant Staphylococcus aureus (MRSA)-infected excisional dermal wound mouse model. Negligible toxicity was observed both in vitro and in vivo. Dermal cell migration and angiogenesis were significantly enhanced. In vivo, the CMC/TA/Cu hydrogel induced effective re-epithelialization, collagen deposition, inflammatory alleviation, and MRSA inhibition during wound repair in mice. All these results confirmed that the CMC/TA/Cu hydrogel is a promising novel dressing for chronic wound healing in clinic.

Advancements and applications of upconversion nanoparticles in wound dressings

Wound healing is a complex process that requires effective management to prevent infections and promote efficient tissue regeneration. In recent years, upconversion nanoparticles (UCNPs) have emerged as promising materials for wound dressing applications due to their unique optical properties and potential therapeutic functionalities. These nanoparticles possess enhanced antibacterial properties when functionalized with antibacterial agents, helping to prevent infections, a common complication in wound healing. They can serve as carriers for controlled drug delivery, enabling targeted release of therapeutic agents to the wound site, allowing for tailored treatment and optimal healing conditions. These nanoparticles possess the ability to convert near-infrared (NIR) light into the visible and/or ultraviolet (UV) regions, making them suitable for therapeutic (photothermal therapy and photodynamic therapy) and diagnostic applications. In the context of wound healing, these nanoparticles can be combined with other materials such as hydrogels, fibers, metal-organic frameworks (MOFs), graphene oxide, etc., to enhance the healing process and prevent the growth of microbial infections. Notably, UCNPs can act as sensors for real-time monitoring of the wound healing progress, providing valuable feedback to healthcare professionals. Despite their potential, the use of UCNPs in wound dressing applications faces several challenges. Ensuring the stability and biocompatibility of UCNPs under physiological conditions is crucial for their effective integration into dressings. Comprehensive safety and efficacy evaluations are necessary to understand potential risks and optimize UCNP-based dressings. Scalability and cost-effectiveness of UCNP synthesis and manufacturing processes are important considerations for practical applications. In addition, efficient incorporation of UCNPs into dressings, achieving uniform distribution, poses an important challenge that needs to be addressed. Future research should prioritize addressing concerns regarding stability and biocompatibility, efficient integration into dressings, rigorous safety evaluation, scalability, and cost-effectiveness. The purpose of this review is to critically evaluate the advantages, challenges, and key properties of UCNPs in wound dressing applications to provide insights into their potential as innovative solutions for enhancing wound healing outcomes. We have provided a detailed description of various types of smart wound dressings, focusing on the synthesis and biomedical applications of UCNPs, specifically their utilization in different types of wound dressings.

Use of over-the-counter mouthwashes as an additional measure in individual oral prophylaxis on adults with plaque-induced gingivitis: a double-blind, parallel, randomized controlled trial

BACKGROUND

Plaque-induced gingivitis is a chronic inflammatory condition characterized by complete reversibility of tissue damage once the periodontal biofilm has been disorganised. The aim of this study was to evaluate the efficacy of two commercially available mouthwashes (MWs) versus a chlorhexidine (CHX) 0.12% MW in reducing gingival bleeding (GB) in adults with plaque-induced gingivitis.

METHODS

The present study was a double-blind, parallel, randomized controlled trial involving 6492 gingival sites (i.e. 39 subjects × 28 teeth × 6 sites/tooth) aged 18-75 years. During a 2-week period, subjects were randomized to receive MWs: a control CHX 0.12% MW (group C, 1818 sites); a MW test containing CHX 0.09% + Citrox®/P complex (group CX, 2628 sites); a MW test based on natural compounds (group P, 2016 sites). GB was assessed at the inclusion visit (T0) and after 2 weeks of MW use (T1). Analyses of GB were compared between groups and then restricted to subjects with bleeding sites between 10 and 30% (moderate gingivitis) or ≥ 30% (severe gingivitis) at T0. Pairwise comparisons were made between groups and logistic regression was used to identify correlates of GB (T1).

RESULTS

For total bleeding site analysis, GB reduction between T0 and T1 ranged from 23% (C), 26% (CX) and 36% (P), respectively (all p < 0.05). Multiple comparison between groups showed that group C was significantly less effective (p < 0.05) than groups CX and P. Splitting the analysis, in patients with severe gingivitis (≥ 30% bleeding sites at T0), all MWs had a positive effect on GB with a reduction at T1 of 36% (C), 33% (CX) and 42% (P), respectively. While GB reduction between T0 and T1, was significant for all groups, the comparison among groups showed no significant difference between group C and CX, whereas the improvement was significant for group P. On the other hand, in adults with moderate gingivitis (< 30% bleeding sites at T0), only CX and P had a positive effect on GB reduction at T1(9% in CX and 2% in P, respectively), although the differences between the three groups were not significant.

CONCLUSION

The daily use of MWs with natural components (groups P and CX) for 2 weeks should be considered positively as an adjunct to individual oral prophylaxis to reduce GB compared to the control MW containing CHX 0.12% (group C) in healthy adults with plaque-induced gingivitis. For subjects with severe gingivitis, it is advisable to first use natural MW (P) and then MW based on CHX 0.09% with natural components (CX), compared to MW with CHX 0.12% (C). For adults with moderate gingivitis, P and CX can be advisable, even if no definitive recommendations can be drawn.

TRIAL REGISTRATION

ACTRN12622000215729, 07/02/2022.

Stimuli-responsive polysaccharide-based smart hydrogels for diabetic wound healing: Design aspects, preparation methods and regulatory perspectives

Diabetes adversely affects wound-healing responses, leading to the development of chronic infected wounds. Such wound microenvironment is characterized by hyperglycaemia, hyperinflammation, hypoxia, variable pH, upregulation of matrix metalloproteinases, oxidative stress, and bacterial colonization. These pathological conditions pose challenges for the effective wound healing. Therefore, there is a paradigm shift in diabetic wound care management wherein abnormal pathological conditions of the wound microenvironment is used as a trigger for controlling the drug release or to improve properties of wound dressings. Hydrogels composed of natural polysaccharides showed tremendous potential as wound dressings as well as stimuli-responsive materials due to their unique properties such as biocompatibility, biodegradability, hydrophilicity, porosity, stimuli-responsiveness etc. Hence, polysaccharide-based hydrogels have emerged as advanced healthcare materials for diabetic wounds. In this review, we presented important aspects for the design of hydrogel-based wound dressings with an emphasis on biocompatibility, biodegradability, entrapment of therapeutic agents, moisturizing ability, swelling, and mechanical properties. Further, various crosslinking methods that enable desirable properties and stimuli responsiveness to the hydrogels have been mentioned. Subsequently, state-of-the-art developments in mono- and multi- stimuli-responsive hydrogels have been presented along with the case studies. Finally regulatory perspectives, challenges for the clinical translation and future prospects have been discussed.

Degradable Polymeric Bio(nano)materials and Their Biomedical Applications: A Comprehensive Overview and Recent Updates

Degradable polymers (both biomacromolecules and several synthetic polymers) for biomedical applications have been promising very much in the recent past due to their low cost, biocompatibility, flexibility, and minimal side effects. Here, we present an overview with updated information on natural and synthetic degradable polymers where a brief account on different polysaccharides, proteins, and synthetic polymers viz. polyesters/polyamino acids/polyanhydrides/polyphosphazenes/polyurethanes relevant to biomedical applications has been provided. The various approaches for the transformation of these polymers by physical/chemical means viz. cross-linking, as polyblends, nanocomposites/hybrid composites, interpenetrating complexes, interpolymer/polyion complexes, functionalization, polymer conjugates, and block and graft copolymers, are described. The degradation mechanism, drug loading profiles, and toxicological aspects of polymeric nanoparticles formed are also defined. Biomedical applications of these degradable polymer-based biomaterials in and as wound dressing/healing, biosensors, drug delivery systems, tissue engineering, and regenerative medicine, etc., are highlighted. In addition, the use of such nano systems to solve current drug delivery problems is briefly reviewed.

Biogenic Vaterite Calcium Carbonate-Silver/Poly(Vinyl Alcohol) Film for Wound Dressing

Vaterite, a spherical polymorph of CaCO3, shows potential as a carrier for the stable and controlled release of silver nanoparticles (AgNPs), preventing their aggregation or loss of efficacy during application. Furthermore, the embedding of CaCO3-Ag in a poly(vinyl alcohol) (PVA) matrix helps effectively encapsulate and protect the CaCO3-Ag microspheres and provides mechanical stability for better contact with the wound surface. This article focuses on the fabrication of an antimicrobial and biocompatible absorbent film embedded with precipitated biogenic vaterite CaCO3-Ag microspheres. The impact of vaterite CaCO3-Ag on the physical, chemical, nanomechanical, biocompatibility, and antimicrobial properties of the PVA films was investigated. The morphology study revealed a bilayer film structure with an inactive and active surface containing homogeneously distributed vaterite CaCO3-Ag. The X-ray photoelectron spectroscopy (XPS) analysis of the spin-orbit splitting in the Ag 3d5/2 and Ag 3d3/2 peaks indicated the presence of both metallic and ionic states of silver in vaterite CaCO3-Ag prior to its incorporation into the PVA polymer matrix. However, upon embedding in the PVA matrix, a subsequent transformation to solely ionic states was observed. The nanomechanical properties of PVA improved, and the reduced modulus and hardness increased to 14.62 ± 5.23 and 0.64 ± 0.29 GPa, respectively. The films demonstrate a significant activity toward Gram-negative Escherichia coli bacteria. The release of AgNPs was studied in both open and closed systems at pH 6, mimicking the pH environment of the wound, and it demonstrated a dependency on the type of capping agent used for synthesis and loading of AgNPs. The results further revealed the biocompatibility of the prepared films with human dermal fibroblast cells at a concentration of ≤5 mg/mL, making them applicable and functional for wound dressing applications.

Chitosan bioactive glass scaffolds for in vivo subcutaneous implantation, toxicity assessment, and diabetic wound healing upon animal model

This study aims to develop chitosan-bioactive glass (BG) scaffolds for diabetic wound healing, toxicity valuation, and subcutaneous implantation in animals for biocompatibility assessment. The scaffolds were prepared by lyophilization technique. In specific BG without sodium (Na), composited with chitosan for better biological activities. The equipped scaffolds were studied for their physiochemical, biological, in vitro and in vivo performances. The chitosan and chitosan-BG (Na free) scaffolds show reliable biocompatibility, cytocompatibility, anti-oxidant, and tissue regeneration. The biocompatibility, toxicity assessments, and diabetic skin wound healing experiments were examined through in vivo studies using Sprague Dawley rats. The extracted tissue samples were analyzed using hematoxylin-eosin- (H and E) and Masson's trichrome staining. Further, tissue excised after scaffold implantation declared non-toxic, non-allergic, and anti-inflammatory nature of chitosan scaffolds. Moreover, the total ribonucleic acid (RNA) expression levels were measured using reverse transcription-polymerase chain reaction (RT-PCR) for the scaffolds against vascular endothelial growth factor (VEGF), and collagen type one (Col-1) primers. Admirably, the scaffolds achieved the best level of skin wound healing via tissue regeneration by increasing epithetical cell formation and collagen deposition. Thus, the biocompatibility, non-toxicity, anti-inflammatory, and wound healing efficiency proved that the chitosan-BG (Na free) scaffold can be readily substantial for wound healing.

Recent progress in polysaccharide and polypeptide based modern moisture-retentive wound dressings

Wounds were considered as defects in the tissues of the human skin and wound healing is said to be a tedious process as there are possibilities of infection or inflammation due to microorganisms. Modern moisture-retentive wound dressing (MMRWD) is opening a new window toward wound therapy. It comprises different types of wound dressing that has classified based on their functionality. Selective polysaccharide-polypeptide fiber composite materials such as hydrogels, hydrocolloids, hydro fibers, transparent-film dressing, and alginate dressing are discussed in this review as a type of MMRWD. The highlight of this polysaccharide and polypeptide based MMRWD is that it supports and enhances the healing of different types of wounds by moisture absorption thus preventing infection. This study has given enlightenment on the application of selected polysaccharide and polypeptide based MMRWD that enhances wound healing actions still it has been observed that the composite wound healing dressing is more effective than the single one. The nano-sized materials (synthetic nano drugs and phyto drugs) were found to increase the efficiency of healing action while coated in the wound dressing material. Future research is required to find out more possibilities of the different composite types of wound dressing in the healing action.

Biomolecules based hydrogels and their potential biomedical applications: A comprehensive review

The need for biocompatible drug carriers has been significantly increased from the past few years. Researchers show great interest in the development of more versatile and sophisticated biomaterials based drug carriers. Hydrogels are beneficial drug carriers and easily release the controlled amount of drug at target site due to its tunable structure. The hydrogels made-up of potent biological macromolecules including collagen, gelatin, fibrin, elastin, fibroin, chitosan, starch, alginate, agarose and carrageenan have been proven as versatile biomaterials. These are three-dimensional polymeric networks, synthesized by crosslinking of hydrophilic polymers. The biological macromolecules based hydrogels containing therapeutic substances are used in a wide range of biomedical applications including wound healing, tissue engineering, cosmetics and contact lenses. However, many aspects related to hydrogels such as the mechanism of cross-linking and molecular entanglement are not clear. So, there is a need to do more research and exploration toward the extensive and cost-effective use of hydrogels. The present review article elaborately discusses the biomolecules based hydrogels and their possible biomedical applications in different fields.

Organic and Biogenic Nanocarriers as Bio-Friendly Systems for Bioactive Compounds' Delivery: State-of-the Art and Challenges

"Green" strategies to build up novel organic nanocarriers with bioperformance are modern trends in nanotechnology. In this way, the valorization of bio-wastes and the use of living systems to develop multifunctional organic and biogenic nanocarriers (OBNs) have revolutionized the nanotechnological and biomedical fields. This paper is a comprehensive review related to OBNs for bioactives' delivery, providing an overview of the reports on the past two decades. In the first part, several classes of bioactive compounds and their therapeutic role are briefly presented. A broad section is dedicated to the main categories of organic and biogenic nanocarriers. The major challenges regarding the eco-design and the fate of OBNs are suggested to overcome some toxicity-related drawbacks. Future directions and opportunities, and finding "green" solutions for solving the problems related to nanocarriers, are outlined in the final of this paper. We believe that through this review, we will capture the attention of the readers and will open new perspectives for new solutions/ideas for the discovery of more efficient and "green" ways in developing novel bioperformant nanocarriers for transporting bioactive agents.

Bioactive Composite Cryogels Based on Poly (Vinyl Alcohol) and a Polymacrolactone as Tissue Engineering Scaffolds: In Vitro and In Vivo Studies

In light of the increasing resistance of pathogenic microorganisms to the action of antibiotics, essential oils extracted from plants with therapeutic activity provide a significant alternative to obtaining dressings for the treatment of skin wounds. The encapsulation of essential oils in an amphiphilic gel network allows better dispersion and preservation of hydrophobic bioactive substances while promoting their prolonged release. In this study, we focused on the development of a poly (vinyl alcohol) (PVA)/poly (ethylene brassylate-co-squaric acid) (PEBSA) platform embedded with thymol (Thy), and α-tocopherol (α-Tcp) as a co-drug structure with prospective use for the treatment and healing of skin wounds. The new complex bioactive system was prepared through repeated freeze-thaw processes. The influence of the composition on surface topography, hydrophilic/hydrophobic character, and in vitro interaction with simulated body fluids was evidenced. BALB/3T3 fibroblast cell culture demonstrated the cryogel scaffolds' cytocompatibility. Tests on Wistar rats confirmed their biocompatibility, integration with host tissue, and the absence of inflammatory processes. The bioactive compound significantly enhanced the healing process of full-thickness excision wounds in a rat model. Further investigations on in vivo infection models would assess the potential of the PVA/PEBSA platform with dual bioactive activity for clinical antimicrobial and wound healing therapy.

Fish Scale Gelatin Nanofibers with Helichrysum italicum and Lavandula latifolia Essential Oils for Bioactive Wound-Healing Dressings

Essential oils are valuable alternatives to synthetic antibiotics that have the potential to avoid the pathogen resistance side effects generated by leather. Helichrysum italicum and Lavandula latifolia essential oils combined with fish scale gelatin were electrospun using a coaxial technique to design new bioactive materials for skin wound dressings fabrication. Fish scale gelatins were extracted from carp fish scales using two variants of the same method, with and without ethylenediaminetetraacetic acid (EDTA). Both variants showed very good electrospinning properties when dissolved in acetic acid solvent. Fish scale gelatin nanofibers with Helichrysum italicum and Lavandula latifolia essential oil emulsions ensured low microbial load (under 100 CFU/g of total number of aerobic microorganisms and total number of yeasts and filamentous fungi) and the absence of Staphylococcus aureus ATCC 6538, Escherichia coli ATCC 10536, and Candida albicans ATCC 1023 as compared to fish scale gelatin without essential oils, which recommends them for pharmaceutical or topical applications. A scratch-test performed on human dermal fibroblasts proved that the biomaterials contributing to the wound healing process included fish scale gelatin nanofibers without EDTA (0.5% and 1%), fish scale gelatin nanofibers without EDTA and Lavandula latifolia essential oil emulsion (1%), fish scale gelatin nanofibers with EDTA (0.6%), and fish scale gelatin nanofibers with EDTA with Helichrysum italicum essential oil emulsion (1% and 2%).

Multifunctional Hydrogels Based on Cellulose and Modified Lignin for Advanced Wounds Management

Considering the complex process of wound healing, it is expected that an optimal wound dressing should be able to overcome the multiple obstacles that can be encountered in the wound healing process. An ideal dressing should be biocompatible, biodegradable and able to maintain moisture, as well as allow the removal of exudate, have antibacterial properties, protect the wound from pathogens and promote wound healing. Starting from this desideratum, we intended to design a multifunctional hydrogel that would present good biocompatibility, the ability to provide a favorable environment for wound healing, antibacterial properties, and also, the capacity to release drugs in a controlled manner. In the preparation of hydrogels, two natural polymers were used, cellulose (C) and chemically modified lignin (LE), which were chemically cross-linked in the presence of epichlorohydrin. The structural and morphological characterization of CLE hydrogels was performed by ATR-FTIR spectroscopy and scanning electron microscopy (SEM), respectively. In addition, the degree of swelling of CLE hydrogels, the incorporation/release kinetics of procaine hydrochloride (PrHy), and their cytotoxicity and antibacterial properties were investigated. The rheological characterization, mechanical properties and mucoadhesion assessment completed the study of CLE hydrogels. The obtained results show that CLE hydrogels have an increased degree of swelling compared to cellulose-based hydrogel, a better capacity to encapsulate PrHy and to control the release of the drug, as well as antibacterial properties and improved mucoadhesion. All these characteristics highlight that the addition of LE to the cellulose matrix has a positive impact on the properties of CLE hydrogels, confirming that these hydrogels can be considered as potential candidates for applications as oral wound dressings.