Sodium alginate hydrogel containing platelet-rich plasma for wound healing

Carboxymethyl cellulose/sodium alginate hydrogel with anti-inflammatory capabilities for accelerated wound healing; In vitro and in vivo study

Recently, managing the chronic skin wounds has become increasingly challenging for healthcare professionals due to the intricate orchestration of cellular and molecular processes involved that lead to the uncontrollable inflammatory reactions which hinder the healing process. Therefore, different types of wound dressings with immunomodulatory properties have been developed in recent years to effectively regulate the immune responses, enhance angiogenesis, promote re-epithelialization, and accelerate the wound healing process. This study aims to develop a new type of immunomodulatory wound dressing utilizing carboxymethyl cellulose (CMC)/sodium alginate (Alg)-simvastatin (SIM) to simultaneously enhance the inflammatory responses and the wound healing ratio. The CMC/Alg-SIM hydrogels exhibited appropriate swelling ratio, water vapor transmission rate, and desirable degradation rate, depending on the SIM content. The fabricated dressing showed sustained release of SIM (during 5 days) that improved the proliferation of skin cells. According to the in vitro findings, the CMC/Alg-SIM hydrogel exhibited controlled pro-inflammatory responses (decreased 2.5- and 1.6-times IL-6 and TNF-α, respectively) and improved secretion of anti-inflammatory cytokines (increased 1.5- and 1.3-times IL-10 and TGF-β, respectively) in comparison with CMC/Alg. Furthermore, the CMC/Alg-SIM hydrogel facilitated rapid wound healing in the rat model with a full-thickness skin defect. After 14 days post-surgery, the wound healing ratio in the CMC/Alg hydrogel group (∼93%) was significantly greater than the control group (∼58%). Therefore, the engineered CMC/Alg-SIM hydrogel with desired immunomodulatory properties possesses the potential to enhance and accelerate skin regeneration for the management of chronic wound healing.

Emerging trends and challenges in polysaccharide derived materials for wound care applications: A review

Polysaccharides are favourable and promising biopolymers for wound care applications due to their abundant natural availability, low cost and excellent biocompatibility. They possess different functional groups, such as carboxylic, hydroxyl and amino, and can easily be modified to obtain the desirable properties and various forms. This review systematically analyses the recent progress in polysaccharides derived materials for wound care applications, emphasizing the most commonly used cellulose, chitosan, alginate, starch, dextran and hyaluronic acid derived materials. The distinctive attributes of each polysaccharide derived wound care material are discussed in detail, along with their different forms, i.e., films, membranes, sponges, nanoemulsions, nanofibers, scaffolds, nanocomposites and hydrogels. The processing methods to develop polysaccharides derived wound care materials are also summarized. In the end, challenges related to polysaccharides derived materials in wound care management are listed, and suggestions are given to expand their utilization in the future to compete with conventional wound healing materials.

Recent research advances in polysaccharide-based hemostatic materials: A review

Massive bleeding resulting from civil and martial accidents can often lead to shock or even death, highlighting the critical need for the development of rapid and efficient hemostatic materials. While various types of hemostatic materials are currently utilized in clinical practice, they often come with limitations such as poor biocompatibility, toxicity, and biodegradability. Polysaccharides, such as alginate (AG), chitosan (CS), cellulose, starch, hyaluronic acid (HA), and dextran, have exhibit excellent biocompatibility and in vivo biodegradability. Their degradation products are non-toxic to surrounding tissues and can be absorbed by the body. As a result, polysaccharides have been extensively utilized in the development of hemostatic materials and have gained significant attention in the field of in vivo hemostasis. This review offers an overview of the different forms, hemostatic mechanisms, and specific applications of polysaccharides. Additionally, it discusses the future opportunities and challenges associated with polysaccharide-based hemostats.

Advances of biological macromolecules hemostatic materials: A review

Achieving hemostasis is a necessary intervention to rapidly and effectively control bleeding. Conventional hemostatic materials currently used in clinical practice may aggravate the damage at the bleeding site due to factors such as poor adhesion and poor adaptation. Compared to most traditional hemostatic materials, polymer-based hemostatic materials have better biocompatibility and offer several advantages. They provide a more effective method of stopping bleeding and avoiding additional damage to the body in case of excessive blood loss. Various hemostatic materials with greater functionality have been developed in recent years for different organs using diverse design strategies. This article reviews the latest advances in the development of polymeric hemostatic materials. We introduce the coagulation cascade reaction after bleeding and then discuss the hemostatic mechanisms and advantages and disadvantages of various polymer materials, including natural, synthetic, and composite polymer hemostatic materials. We further focus on the design strategies, properties, and characterization of hemostatic materials, along with their applications in different organs. Finally, challenges and prospects for the application of hemostatic polymeric materials are summarized and discussed. We believe that this review can provide a reference for related research on hemostatic materials, contributing to the further development of polymer hemostatic materials.

Mussel-inspired tissue adhesive composite hydrogel with photothermal and antioxidant properties prepared from pectin for burn wound healing

Biodegradable self-healing hydrogels with antibacterial property attracted growing attentions in biomedication as wound dressings since they can prevent bacterial infection and promote wound healing process. In this research, a biodegradable self-healing hydrogel with ROS scavenging performance and enhanced tissue adhesion was fabricated from dopamine grafted oxidized pectin (OPD) and naphthoate hydrazide terminated PEO (PEO NH). At the same time, Fe3+ ions were incorporated to endow the hydrogel with near-infrared (NIR) triggered photothermal property to obtain antibacterial activity. The composite hydrogel showed good hemostasis performance based on mussel inspired tissue adhesion with biocompatibility well preserved. As expected, the composition of FeCl3 improved conductivity and endowed photothermal property to the hydrogel. The in vivo wound repairing experiment revealed the 808 nm NIR light triggered photothermal behavior of the hydrogel reduced the inflammation response and promoted wound repairing rate. As a result, this composite FeCl3/hydrogel shows great potential to be an excellent wound dressing for the treatment of infection prong wounds with NIR triggers.

Enhanced wound regeneration by PGS/PLA fiber dressing containing platelet-rich plasma: an in vitro study

Novel wound dressings with therapeutic effects are being continually designed to improve the wound healing process. In this study, the structural, chemical, physical, and biological properties of an electrospun poly glycerol sebacate/poly lactide acid/platelet-rich plasma (PGS/PLA-PRP) nanofibers were evaluated to determine its impacts on in vitro wound healing. Results revealed desirable cell viability in the Fibroblast (L929) and macrophage (RAW-264.7) cell lines as well as human umbilical vein endothelial cells (HUVEC). Cell migration was evident in the scratch assay (L929 cell line) so that it promoted scratch contraction to accelerate in vitro wound healing. Moreover, addition of PRP to the fiber structure led to enhanced collagen deposition (~ 2 times) in comparison with PGS/PLA scaffolds. While by addition PRP to PGS/PLA fibers not only decreased the expression levels of pro-inflammatory cytokines (IL-6 and TNF-α) in RAW-264.7 cells but also led to significantly increased levels of cytokine (IL-10) and the growth factor (TGF-β), which are related to the anti-inflammatory phase (M2 phenotype). Finally, PGS/PLA-PRP was found to induce a significant level of angiogenesis by forming branching points, loops, and tubes. Based on the results obtained, the PGS/PLA-PRP dressing developed might be a promising evolution in skin tissue engineering ensuring improved wound healing and tissue regeneration.

Progress in the Preparation and Application of Inulin-Based Hydrogels

Inulin, a natural polysaccharide, has emerged as a promising precursor for the preparation of hydrogels due to its biocompatibility, biodegradability, and structural versatility. This review provides a comprehensive overview of the recent progress in the preparation, characterization, and diverse applications of inulin-based hydrogels. Different synthesis strategies, including physical methods (thermal induction and non-thermal induction), chemical methods (free-radical polymerization and chemical crosslinking), and enzymatic approaches, are discussed in detail. The unique properties of inulin-based hydrogels, such as stimuli-responsiveness, antibacterial activity, and their potential as fat replacers, are highlighted. Special emphasis is given to their promising applications in drug delivery systems, especially for colon-targeted delivery, due to the selective degradation of inulin via colonic microflora. The ability to incorporate both hydrophilic and hydrophobic drugs further expands their therapeutic potential. In addition, the applications of inulin-based hydrogels in responsive materials, the food industry, wound dressings, and tissue engineering are discussed. While significant progress has been achieved, challenges and prospects in optimizing synthesis, improving mechanical properties, and exploring new functionalities are discussed. Overall, this review highlights the remarkable properties of inulin-based hydrogels as a promising class of biomaterials with immense potential in the biomedical, pharmaceutical, and materials science fields.

Bioarchitectural Design of Bioactive Biopolymers: Structure-Function Paradigm for Diabetic Wound Healing

Chronic wounds such as diabetic ulcers are a major complication in diabetes caused by hyperglycemia, prolonged inflammation, high oxidative stress, and bacterial bioburden. Bioactive biopolymers have been found to have a biological response in wound tissue microenvironments and are used for developing advanced tissue engineering strategies to enhance wound healing. These biopolymers possess innate bioactivity and are biodegradable, with favourable mechanical properties. However, their bioactivity is highly dependent on their structural properties, which need to be carefully considered while developing wound healing strategies. Biopolymers such as alginate, chitosan, hyaluronic acid, and collagen have previously been used in wound healing solutions but the modulation of structural/physico-chemical properties for differential bioactivity have not been the prime focus. Factors such as molecular weight, degree of polymerization, amino acid sequences, and hierarchical structures can have a spectrum of immunomodulatory, anti-bacterial, and anti-oxidant properties that could determine the fate of the wound. The current narrative review addresses the structure-function relationship in bioactive biopolymers for promoting healing in chronic wounds with emphasis on diabetic ulcers. This review highlights the need for characterization of the biopolymers under research while designing biomaterials to maximize the inherent bioactive potency for better tissue regeneration outcomes, especially in the context of diabetic ulcers.

Fabrication of yeast β-glucan/sodium alginate/γ-polyglutamic acid composite particles for hemostasis and wound healing

Particles with a porous structure can lead to quick hemostasis and provide a good matrix for cell proliferation during wound healing. Recently, many particle-based wound healing materials have been clinically applied. However, these products show good hemostatic ability but with poor wound healing ability. To solve this problem, this study fabricated APGG composite particles using yeast β-glucan (obtained from Saccharomyces cerevisiae), sodium alginate, and γ-polyglutamic acid as the starting materials. The structure of yeast β-glucan was modified with many carboxymethyl groups to obtain carboxymethylated β-glucan, which could coordinate with Ca2+ ions to form a crosslinked structure. A morphology study indicated that the APGG particles showed an irregular spheroidal structure with a low density (<0.1 g cm-3) and high porosity (>40%). An in vitro study revealed that the particles exhibited a low BCI value, low hemolysis ratio, and good cytocompatibility against L929 cells. The APGG particles could quickly stop bleeding in a mouse liver injury model and exhibited better hemostatic ability than the commercially available product Celox. Furthermore, the APGG particles could accelerate the healing of non-infected wounds, and the expression levels of CD31, α-SMA, and VEGF related to angiogenesis were significantly enhanced.

Essential elements for spatiotemporal delivery of growth factors within bio-scaffolds: A comprehensive strategy for enhanced tissue regeneration

The precise delivery of growth factors (GFs) in regenerative medicine is crucial for effective tissue regeneration and wound repair. However, challenges in achieving controlled release, such as limited half-life, potential overdosing risks, and delivery control complexities, currently hinder their clinical implementation. Despite the plethora of studies endeavoring to accomplish effective loading and gradual release of GFs through diverse delivery methods, the nuanced control of spatial and temporal delivery still needs to be elucidated. In response to this pressing clinical imperative, our review predominantly focuses on explaining the prevalent strategies employed for spatiotemporal delivery of GFs over the past five years. This review will systematically summarize critical aspects of spatiotemporal GFs delivery, including judicious bio-scaffold selection, innovative loading techniques, optimization of GFs activity retention, and stimulating responsive release mechanisms. It aims to identify the persisting challenges in spatiotemporal GFs delivery strategies and offer an insightful outlook on their future development. The ultimate objective is to provide an invaluable reference for advancing regenerative medicine and tissue engineering applications.

Developing natural polymers for skin wound healing

Natural polymers are complex organic molecules that occur in the natural environment and have not been subjected to artificial synthesis. They are frequently encountered in various creatures, including mammals, plants, and microbes. The aforementioned polymers are commonly derived from renewable sources, possess a notable level of compatibility with living organisms, and have a limited adverse effect on the environment. As a result, they hold considerable significance in the development of sustainable and environmentally friendly goods. In recent times, there has been notable advancement in the investigation of the potential uses of natural polymers in the field of biomedicine, specifically in relation to natural biomaterials that exhibit antibacterial and antioxidant characteristics. This review provides a comprehensive overview of prevalent natural polymers utilized in the biomedical domain throughout the preceding two decades. In this paper, we present a comprehensive examination of the components and typical methods for the preparation of biomaterials based on natural polymers. Furthermore, we summarize the application of natural polymer materials in each stage of skin wound repair. Finally, we present key findings and insights into the limitations of current natural polymers and elucidate the prospects for their future development in this field.

Engineering a self-healing grafted chitosan-sodium alginate based hydrogel with potential keratinocyte cell migration property and inhibitory effect against fluconazole resistance Candida albicans biofilm

Biofilms developed by microorganisms cause an extremely severe clinical problem that leads to drug failure. Bioactive polymeric hydrogels display potential for controlling the formation of microorganism-based biofilms, but their rapid biodegradability in these biofilm sites is still a major challenge. To overcome this, chitosan (CS), a natural functional biomaterial, has been used because of its effective penetrability in the cell wall of microorganisms; however, its fast biodegradability has restricted its further use. Hence, in this study, to improve the stability of CS and increase its penetration retention inside a biofilm, grafted CS was prepared and then crosslinked with sodium alginate (SA) to synthesize CS-poly(MA-co-AA)SA hydrogel via a free radical grafting method, therefore enhancing its antibiofilm efficiency against biofilms. The prepared hydrogel demonstrated excellent effectiveness against (≥90 % inhibition) biofilms of Candida albicans. Additionally, in vitro and in vivo safety assays established that the prepared hydrogel can be used in a biofilm microenvironment and might reduce drug resistance burden owing to its long-term antibiofilm effect and improved CS stability at the biofilm site. Furthermore, in vitro wound healing outcomes of hydrogel indicated its potential application for chronic wound treatment. This research opens a new advanced strategy for biofilm-associated infection treatment, including wound treatment.

Hydrogel-Based Skin Regeneration

The skin is subject to damage from the surrounding environment. The repair of skin wounds can be very challenging due to several factors such as severe injuries, concomitant infections, or comorbidities such as diabetes. Different drugs and wound dressings have been used to treat skin wounds. Tissue engineering, a novel therapeutic approach, revolutionized the treatment and regeneration of challenging tissue damage. This field includes the use of synthetic and natural biomaterials that support the growth of tissues or organs outside the body. Accordingly, the demand for polymer-based therapeutic strategies for skin tissue defects is significantly increasing. Among the various 3D scaffolds used in tissue engineering, hydrogel scaffolds have gained special significance due to their unique properties such as natural mimicry of the extracellular matrix (ECM), moisture retention, porosity, biocompatibility, biodegradability, and biocompatibility properties. First, this article delineates the process of wound healing and conventional methods of treating wounds. It then presents an examination of the structure and manufacturing methods of hydrogels, followed by an analysis of their crucial characteristics in healing skin wounds and the most recent advancements in using hydrogel dressings for this purpose. Finally, it discusses the potential future advancements in hydrogel materials within the realm of wound healing.

Multifunctional hydrogel bioscaffolds based on polysaccharide to promote wound healing: A review

Various types of skin wounds pose challenges in terms of healing and susceptibility to infection, which can have a significant impact on physical and mental well-being, and in severe cases, may result in amputation. Conventional wound dressings often fail to provide optimal support for these wounds, thereby impeding the healing process. As a result, there has been considerable interest in the development of multifunctional polymer matrix hydrogel scaffolds for wound healing. This review offers a comprehensive review of the characteristics of polysaccharide-based hydrogel scaffolds, as well as their applications in different types of wounds. Additionally, it evaluates the advantages and disadvantages associated with various types of multifunctional polymer and polysaccharide-based hydrogel scaffolds. The objective is to provide a theoretical foundation for the utilization of multifunctional hydrogel scaffolds in promoting wound healing.

Fabrication and investigation of a pentamerous composite based on calix[4]arene functionalized graphene oxide grafted with silk fibroin, cobalt ferrite, and alginate

This paper presents a new scaffold made from graphene oxide nanosheets, calix[4]arene supramolecules, silk fibroin proteins, cobalt ferrite nanoparticles, and alginate hydrogel (GO-CX[4]/SF/CoFe2O4/Alg). After preparing the composite, we conducted various analyses to examine its structure. These analyses included FTIR, XRD, SEM, EDS, VSM, DLS, and zeta potential tests. Additionally, we performed tests to evaluate the swelling ratio, rheological properties, and compressive mechanical strength of the material. The biological capability of the composite was tested through biocompatiblity, anticancer, hemolysis, antibacterial anti-biofilm assays. Besides, the rheological properties and swelling behaviour of the composite were studied. The results showed that the scaffold is biocompatible with Hu02 cells and the cell viability percentages of 85.23 %, 82.78 %, and 80.18 % for were acquired for 24, 48, and 72 h, respectively. In contrast, the cell viability percentage of BT549 cancer cells were obtained 65.79 %, 60.45 % and 58.16 % for same period which confirmed notable anticancer activity of the product composite. Moreover, a significant antibacterial growth inhibition against E. coli and S. aureus species highlights its potential as an effective antibacterial agent. Furthermore, the observed minimal hemolytic effect (6.56 %) and strong inhibition of P. aeruginosa biofilm formation with a low OD value (0.24) indicate notable hemocompatibility and antibacterial activity.

Development and Analysis of Silver Nitroprusside Nanoparticle-Incorporated Sodium Alginate Films for Banana Browning Prevention

Banana (Musa acuminate) has been popular among consumers worldwide due to its rich nutrients and minerals. However, bananas are highly susceptible to the physical and biological factors that lead to postharvest loss during transportation and storage. In this work, novel sodium alginate (SA) films incorporated with silver nitroprusside nanoparticles (AgNNPs) were prepared to extend the shelf life of bananas through antibacterial and antioxidant coating. The results exhibited that AgNNPs were cubical and that their size was <500 nm, with metal composition being Ag and Fe. Additionally, the incorporation of AgNNPs in the SA film was seen in FE-SEM and zeta analysis, with an average size of about 365.6 nm. Furthermore, the functional and crystalline properties of AgNNPs were assessed through FTIR and XRD. Transmittance testing of the SA-AgNNPs films confirmed they have good UV barrier properties. SA-AgNNPs films exhibited excellent high antibacterial activity against foodborne pathogens including L. monocytogenes, S. enterica, and E. coli at the concentration of 500 µg/mL. Moreover, during the storage of bananas, SA-AgNNPs nanocomposite coatings act as a barrier to microbial contamination and slow down the ripening of bananas. As a result, compared with SA-coated and uncoated bananas, SA-AgNNPs-coated bananas exhibited the lowest weight loss and lowest total bacterial colonies, thus greatly extending their shelf life. Particularly when coated with SA-AgNNPs films, total bacterial colonies (TBC) in the banana peel and pulp were as low as 1.13 × 103 and 51 CUF/g on the ninth day of storage, respectively. Our work offers an efficient strategy to improve the quality of bananas during the postharvest period, with extensive applications in fruit preservation and food packing.

Structure-activity relationships of bioactive polysaccharides extracted from macroalgae towards biomedical application: A review

Macroalgae are valuable and structurally diverse sources of bioactive compounds among marine resources. The cell walls of macroalgae are rich in polysaccharides which exhibit a wide range of biological activities, such as anticoagulant, antioxidant, antiviral, anti-inflammatory, immunomodulatory, and antitumor activities. Macroalgae polysaccharides (MPs) have been recognized as one of the most promising candidates in the biomedical field. However, the structure-activity relationships of bioactive polysaccharides extracted from macroalgae are complex and influenced by various factors. A clear understanding of these relationships is indeed critical in developing effective biomedical applications with MPs. In line with these challenges and knowledge gaps, this paper summarized the structural characteristics of marine MPs from different sources and relevant functional and bioactive properties and particularly highlighted those essential effects of the structure-bioactivity relationships presented in biomedical applications. This review not only focused on elucidating a particular action mechanism of MPs, but also intended to identify a novel or potential application of these valued compounds in the biomedical field in terms of their structural characteristics. In the last, the challenges and prospects of MPs in structure-bioactivity elucidation were further discussed and predicted, where they were emphasized on exploring modern biotechnology approaches potentially applied to expand their promising biomedical applications.

Progress in injectable hydrogels for the treatment of incompressible bleeding: an update

Uncontrollable haemorrhage from deep, noncompressible wounds remains a persistent and intractable challenge, accounting for a very high proportion of deaths in both war and disaster situations. Recently, injectable hydrogels have been increasingly studied as potential haemostatic materials, highlighting their enormous potential for the management of noncompressible haemorrhages. In this review, we summarize haemostatic mechanisms, commonly used clinical haemostatic methods, and the research progress on injectable haemostatic hydrogels. We emphasize the current status of injectable hydrogels as haemostatic materials, including their physical and chemical properties, design strategy, haemostatic mechanisms, and application in various types of wounds. We discuss the advantages and disadvantages of injectable hydrogels as haemostatic materials, as well as the opportunities and challenges involved. Finally, we propose cutting-edge research avenues to address these challenges and opportunities, including the combination of injectable hydrogels with advanced materials and innovative strategies to increase their biocompatibility and tune their degradation profile. Surface modifications for promoting cell adhesion and proliferation, as well as the delivery of growth factors or other biologics for optimal wound healing, are also suggested. We believe that this paper will inform researchers about the current status of the use of injectable haemostatic hydrogels for noncompressible haemorrhage and spark new ideas for those striving to propel this field forward.

Hydrogels and Wound Healing: Current and Future Prospects

The care and rehabilitation of acute and chronic wounds have a significant social and economic impact on patients and global health. This burden is primarily due to the adverse effects of infections, prolonged recovery, and the associated treatment costs. Chronic wounds can be treated with a variety of approaches, which include surgery, negative pressure wound therapy, wound dressings, and hyperbaric oxygen therapy. However, each of these strategies has an array of limitations. The existing dry wound dressings lack functionality in promoting wound healing and exacerbating pain by adhering to the wound. Hydrogels, which are commonly polymer-based and swell in water, have been proposed as potential remedies due to their ability to provide a moist environment that facilitates wound healing. Their unique composition enables them to absorb wound exudates, exhibit shape adaptability, and be modified to incorporate active compounds such as growth factors and antibacterial compounds. This review provides an updated discussion of the leading natural and synthetic hydrogels utilized in wound healing, details the latest advancements in hydrogel technology, and explores alternate approaches in this field. Search engines Scopus, PubMed, Science Direct, and Web of Science were utilized to review the advances in hydrogel applications over the last fifteen years.

Preparation of pH-responsive oxidized regenerated cellulose hydrogels compounded with nano-ZnO/chitosan/aminocyclodextrin ibuprofen complex for wound dressing

Recently, using oxidized regenerated cellulose (ORC) to build a hydrogel system on promoting healing in wounds has a fast-growing market. However, it remains a challenge to improve the degree of oxidation of regenerated cellulose (RC) and to prepare matrices that are uniquely responsive to the wound environment. Herein, highly oxidized aldehyde-based cellulose from porous RC was prepared by NaBH4-HCl swelling and then NaIO4 oxidation pathway. Chitosan (CS), ethylenediamine-cyclodextrin (EDA-CD) along with ORC have been used to construct hydrogel matrices that are pH-responsive and capable of controlled drug release for use as future wound dressings. And zinc oxide nanoparticles (ZnO NPs) with antimicrobial effect and ibuprofen (IBU) with analgesic effect were piggybacked into the hydrogel system. XRD was used to study the presence of ZnO. SEM was used to observe the surface structure of the prepared hydrogel. TEM was used to observe the particle size of the ZnO NPs. Meanwhile, the oxidation conditions of the ORC were explored. Furthermore, the mechanical, swelling, water retention, cytotoxicity, bacterial inhibition properties and treatment effect, which are closely related to the application of wound dressing, were carefully researched. The unique characteristics of prepared hydrogel, including pH-responsive degradability and sustained release properties of IBU, were also investigated.

Montmorillonite-Sodium Alginate Oral Colon-Targeting Microcapsule Design for WGX-50 Encapsulation and Controlled Release in Gastro-Intestinal Tract

The montmorillonite-sodium alginate (MMT-SA) colon-targeting microcapsules have been designed as a WGX-50 encapsulation and controlled release vehicle used in oral administration. The MMT-SA microcapsule was formed from a cross-linking reaction, and the stable micropore in the microcapsule changed with a different MMT-SA mixed mass ratio. The MMT-SA microcapsule has a reinforced micropore structure and an enhanced swell-dissolution in SIF and SCF with alkaline environment, which is attributed to the incorporated MMT. The MMT-SA microcapsule exhibited a high WGX-50 encapsulation rate up to 98.81 ± 0.31% and an obvious WGX-50 controlled release in the simulated digestive fluid in vitro. The WGX-50 loaded with MMT-SA microcapsule showed a weak minimizing drug loss in SGF (Simulated Gastric Fluid) with an acidic environment, while it showed a strong maximizing drug release in SIF (Simulated Intestinal Fluid) and SCF (Simulated Colonic Fluid) with an alkaline environment. These features make the MMT-SA microcapsule a nominated vehicle for colon disease treatment used in oral administration.

Smart Responsive and Controlled-Release Hydrogels for Chronic Wound Treatment

Chronic wounds are a major health challenge that require new treatment strategies. Hydrogels are promising drug delivery systems for chronic wound healing because of their biocompatibility, hydration, and flexibility. However, conventional hydrogels cannot adapt to the dynamic and complex wound environment, which involves low pH, high levels of reactive oxygen species, and specific enzyme expression. Therefore, smart responsive hydrogels that can sense and respond to these stimuli are needed. Crucially, smart responsive hydrogels can modulate drug release and eliminate pathological factors by changing their properties or structures in response to internal or external stimuli, such as pH, enzymes, light, and electricity. These stimuli can also be used to trigger antibacterial responses, angiogenesis, and cell proliferation to enhance wound healing. In this review, we introduce the synthesis and principles of smart responsive hydrogels, describe their design and applications for chronic wound healing, and discuss their future development directions. We hope that this review will inspire the development of smart responsive hydrogels for chronic wound healing.

Exploring the therapeutic potential of recombinant human lysozyme: a review on wound management system with antibacterial

Lysozyme, a natural antibacterial enzyme protein, possesses the ability to dissolve the cell walls of Gram-positive bacteria, demonstrating broad-spectrum antibacterial activity. Despite its significant potential in treating wound infections and promoting wound healing, its widespread clinical application has yet to be realized. Current research is primarily focused on carrier-based delivery systems for lysozyme. In this review, we discuss four delivery systems that can be employed for lysozyme in wound healing treatment, specifically hydrogels, nanofilms, electrospun fibrous membranes, and modified-lysozyme composite systems. These systems not only enhance the stability of lysozyme but also enable its controlled and sustained release at wound sites, potentially overcoming some of the challenges associated with its direct application. Lastly, we delve into the perspectives and challenges related to the use of these delivery systems, hoping to spur further research and innovation in this promising field.

Hydrogel-Based Therapeutics for Pancreatic Ductal Adenocarcinoma Treatment

Pancreatic ductal adenocarcinoma (PDAC), one of the deadliest malignancies worldwide, is characteristic of the tumor microenvironments (TME) comprising numerous fibroblasts and immunosuppressive cells. Conventional therapies for PDAC are often restricted by limited drug delivery efficiency, immunosuppressive TME, and adverse effects. Thus, effective and safe therapeutics are urgently required for PDAC treatment. In recent years, hydrogels, with their excellent biocompatibility, high drug load capacity, and sustainable release profiles, have been developed as effective drug-delivery systems, offering potential therapeutic options for PDAC. This review summarizes the distinctive features of the immunosuppressive TME of PDAC and discusses the application of hydrogel-based therapies in PDAC, with a focus on how these hydrogels remodel the TME and deliver different types of cargoes in a controlled manner. Furthermore, we also discuss potential drug candidates and the challenges and prospects for hydrogel-based therapeutics for PDAC. By providing a comprehensive overview of hydrogel-based therapeutics for PDAC treatment, this review seeks to serve as a reference for researchers and clinicians involved in developing therapeutic strategies targeting the PDAC microenvironment.

Bioinspired Platelet-Anchored Electrospun Meshes for Tight Inflammation Manipulation and Chronic Diabetic Wound Healing

Tight manipulation of the initial leukocytes infiltration and macrophages plasticity toward the M2 phenotype remain a challenge for diabetic wound healing. Inspired by the platelet function and platelet-macrophage interaction, a platelet-anchored polylactic acid-b-polyethylene glycol-b-polylactic acid (PLA-PEG-PLA) electrospun dressing is developed for inflammatory modulation and diabetic wounds healing acceleration. PLA-PEG-PLA electrospun meshes encapsulated with thymosin β4 (Tβ4) and CaCl2 is fabricated with electrospinning, followed by immersion of electrospun mesh in platelet-rich plasma to firmly anchor the platelets. It is demonstrated that the anchored platelets on electrospun mesh can enhance the initial macrophage recruitment and control the Tβ4 release from electrospun meshes to facilitate the macrophages polarization to the M2 phenotype. The inflammatory regulation promotes the expression of vascular endothelial growth factor and the migration of vascular endothelial cells for angiogenesis, resulting in accelerated diabetic wounds healing. Therefore, this work paved a new way to design platelet-inspired electrospun meshes for inflammation manipulation and diabetic wound healing.

Injectable hydrogel for sustained delivery of progranulin derivative Atsttrin in treating diabetic fracture healing

Hydrogels with long-term storage stability, controllable sustained-release properties, and biocompatibility have been garnering attention as carriers for drug/growth factor delivery in tissue engineering applications. Chitosan (CS)/Graphene Oxide (GO)/Hydroxyethyl cellulose (HEC)/β-glycerol phosphate (β-GP) hydrogel is capable of forming a 3D gel network at physiological temperature (37 °C), rendering it an excellent candidate for use as an injectable biomaterial. This work focused on an injectable thermo-responsive CS/GO/HEC/β-GP hydrogel, which was designed to deliver Atsttrin, an engineered derivative of a known chondrogenic and anti-inflammatory growth factor-like molecule progranulin. The combination of the CS/GO/HEC/β-GP hydrogel and Atsttrin provides a unique biochemical and biomechanical environment to enhance fracture healing. CS/GO/HEC/β-GP hydrogels with increased amounts of GO exhibited rapid sol-gel transition, higher viscosity, and sustained release of Atsttrin. In addition, these hydrogels exhibited a porous interconnected structure. The combination of Atsttrin and hydrogel successfully promoted chondrogenesis and osteogenesis of bone marrow mesenchymal stem cells (bmMSCs) in vitro. Furthermore, the work also presented in vivo evidence that injection of Atsttrin-loaded CS/GO/HEC/β-GP hydrogel stimulated diabetic fracture healing by simultaneously inhibiting inflammatory and stimulating cartilage regeneration and endochondral bone formation signaling pathways. Collectively, the developed injectable thermo-responsive CS/GO/HEC/βG-P hydrogel yielded to be minimally invasive, as well as capable of prolonged and sustained delivery of Atsttrin, for therapeutic application in impaired fracture healing, particularly diabetic fracture healing.

Electroactive Hydrogels with Photothermal/Photodynamic Effects for Effective Wound Healing Assisted by Polydopamine-Modified Graphene Oxide

Antibacterial hydrogel wound dressings have attracted considerable attention in recent years. However, bacterial infections can occur at any point during the wound-healing process. There is a demand for hydrogels that possess on-demand antibacterial and excellent wound repair properties. Herein, we report a near-infrared (NIR)-light-responsive indocyanine green (ICG)-loaded polydopamine (PDA)-mediated graphene oxide (PGO) and amorphous calcium phosphate (CaP)-incorporated poly(vinyl alcohol) (PVA) hydrogel using a mussel-inspired approach. PGO was reduced by PDA, which endowed the hydrogel with electroactivity and provided abundant sites for loading ICG. Amorphous CaP was formed in situ in the PVA hydrogel to enhance its mechanical properties and biocompatibility. Taking advantage of the high photothermal and photodynamic efficiency of ICG-PGO, the ICG-PGO-CaP-PVA hydrogel exhibited fascinating on-demand antibacterial activity through NIR light irradiation. Moreover, the thermally induced gel-sol conversion of PVA accelerated the release of Ca ions and allowed the hydrogel to adapt to irregular wounds. Meanwhile, PGO endows the hydrogel with conductivity and cell affinity, which facilitate endogenous electrical signal transfer to control cell behavior. In vitro and in vivo studies demonstrated that the ICG-PGO-CaP-PVA hydrogel exhibited a strong tissue repair activity under NIR light irradiation. This mussel-inspired strategy offers a novel way to design hydrogel dressings for wound healing.

Engineering a platelet-rich plasma-based multifunctional injectable hydrogel with photothermal, antibacterial, and antioxidant properties for skin regeneration

Wound healing remains a significant challenge worldwide, necessitating the development of new wound dressings to aid in the healing process. This study presents a novel photothermally active hydrogel that contains platelet-rich plasma (PRP) for infected wound healing. The hydrogel was formed in a one pot synthesis approach by mixing alginate (Alg), gelatin (GT), polydopamine (PDA), and PRP, followed by the addition of CaCl2 as a cross-linker to prepare a multifunctional hydrogel (AGC-PRP-PDA). The hydrogel exhibited improved strength and good swelling properties. PDA nanoparticles (NPs) within the hydrogel endowed them with high photothermal properties and excellent antibacterial and antioxidant activities. Moreover, the hydrogels sustained the release of growth factors due to their ability to protect PRP. The hydrogels also exhibited good hemocompatibility and cytocompatibility, as well as high hemostatic properties. In animal experiments, the injectable hydrogels effectively filled irregular wounds and promoted infected wound healing by accelerating re-epithelialization, facilitating collagen deposition, and enhancing angiogenesis. The study also indicated that near-infrared light improved the healing process. Overall, these hydrogels with antibacterial, antioxidant, and hemostatic properties, as well as sustained growth factor release, show significant potential for skin regeneration in full-thickness, bacteria-infected wounds.

Oral hydrogel nanoemulsion co-delivery system treats inflammatory bowel disease via anti-inflammatory and promoting intestinal mucosa repair

BACKGROUND

Due to oral nano-delivery systems for the treatment of inflammatory bowel disease (IBD) are often failed to accumulated to the colonic site and could not achieve controlled drug release, it's urgent to develop a microenvironment responsive drug delivery to improve therapy efficacy. Inflammation at the IBD site is mainly mediated by macrophages, which are the key effector cells. Excessive inflammation leads to oxidative stress and intestinal mucosal damage. The use of curcumin (CUR) and emodin (EMO) together for the treatment of IBD is promising due to their respective anti-inflammatory and intestinal mucosal repair effects. In view of the pH gradient environment of gastrointestinal tract, here we prepared pH-responsive sodium alginate (SA) hydrogel-coated nanoemulsions to co-deliver CUR and EMO (CUR/EMO NE@SA) to achieve controlled drug release and specifically target macrophages of the colon.

RESULTS

In this study, a pH-responsive CUR/EMO NE@SA was successfully developed, in which the CUR/EMO NE was loaded by chitosan and further crosslinked with sodium alginate. CUR/EMO NE@SA had a pH-responsive property and could achieve controlled drug release in the colon. The preparation could significantly alleviate and improve the colon inflammatory microenvironment by decreasing TNF-α and IL-6 expression, increasing IL-10 expression, scavenging reactive oxygen species in macrophages, and by ameliorating the restoration of intestinal mucosal tight junction protein expression. Furthermore, we revealed the molecular mechanism of the preparation for IBD treatment, which might due to the CUR and EMO synergic inhibition of NF-κB to improve the pro-inflammatory microenvironment. Our study provides a new IBD therapy strategy via synergically inhibiting inflammatory, repairing mucosal and clearing ROS by pH-sensitive hydrogel-encapsulated nanoemulsion drug delivery system, which might be developed for other chronic inflammatory disease treatment.

CONCLUSIONS

It's suggested that pH-sensitive hydrogel-coated nanoemulsion-based codelivery systems are a promising combinatorial platform in IBD.

Carboxymethyl Chitosan/Sodium Alginate/Chitosan Quaternary Ammonium Salt Composite Hydrogel Supported 3J for the Treatment of Oral Ulcer

Oral ulcer is a common inflammatory disease of oral mucosa, causing severe burning pain and great inconvenience to daily life. In this study, compound 3J with anti-inflammatory activity was synthesized beforehand. Following that, an intelligent composite hydrogel supported 3J was designed with sodium alginate, carboxymethyl chitosan, and chitosan quaternary ammonium salt as the skeleton, and its therapeutic effect on the rat oral ulcer model was investigated. The results show that the composite hydrogel has a dense honeycomb structure, which is conducive to drug loading and wound ventilation, and has biodegradability. It has certain antibacterial effects and good anti-inflammatory activity. When loaded with 3J, it reduced levels of TNF-α and IL-6 in inflammatory cells by up to 50.0%. It has excellent swelling and water retention properties, with a swelling rate of up to 765.0% in a pH 8.5 environment. The existence of a large number of quaternary ammonium groups, carboxyl groups, and hydroxyl groups makes it show obvious differences in swelling in different pH environments, which proves that it has double pH sensitivity. It is beneficial to adapt to the highly dynamic changes of the oral environment. Compared with single hydrogel or drug treatment, the drug-loaded hydrogel has a better effect on the treatment of oral ulcers.

In situ forming alginate/gelatin hybrid hydrogels containing doxorubicin loaded chitosan/AuNPs nanogels for the local therapy of breast cancer

In this study, pH-sensitive in situ gelling hydrogels based on oxidized alginate and gelatin-containing doxorubicin (DOX) loaded chitosan/gold nanoparticles (CS/AuNPs) nanogels were fabricated via Schiff-base bond formation. The obtained CS/AuNPs nanogels indicated a size distribution of about 209 nm with a zeta potential of +19.2 mV and an encapsulation efficiency of around 72.6 % for DOX. The study of the rheological properties of hydrogels showed that the value of G' is higher than G″ for all hydrogels, which confirms the elastic behavior of hydrogels in the applied frequency range. The rheological and texture analysis demonstrated the higher mechanical properties of hydrogels containing β-GP and CS/AuNPs nanogels. The release profile of DOX after 48 h indicates the 99 % and 73 % release amount at pH = 5.8 and pH = 7.4, respectively. MTT cytotoxicity study showed that the prepared hydrogels are cytocompatible on MCF-7 cells. By the Live/Dead assay, it was demonstrated that the cultured cells on DOX-free hydrogels were almost alive in the presence of CS/AuNPs nanogels. However, the hydrogel-containing drug and free DOX in the same concentration caused high death of MCF-7 cells as expected, which showed the potential of the developed hydrogels for application in the local treatment of breast cancer.

Fumaria officinalis-loaded chitosan nanoparticles dispersed in an alginate hydrogel promote diabetic wounds healing by upregulating VEGF, TGF-β, and b-FGF genes: A preclinical investigation

Diabetic wounds may become chronic if left untreated. In the current study, a potential wound dressing was developed by incorporating fumaria officinalis extract-loaded chitosan nanoparticles (FOE-CHNPs) into calcium alginate hydrogel. The produced hydrogel was evaluated regarding its microarchitecture, cytotoxicity, cell migration activity, cytoprotective potential, porosity, in vitro anti-inflammatory activity, and drug release profile. Then, the healing function of FOE-CHNPs/calcium alginate hydrogel was compared with a marketed wound care product in a rat model of diabetic wound. In vitro study showed that the hydrogel system promoted skin cells viability and migration. In vivo wound healing assay showed that the animals treated with the FOE-CHNPs/calcium alginate hydrogel had comparable wound healing potential with the GranuGEL® as the marketed wound care hydrogel. Gene expression studies showed that FOE-CHNPs/calcium alginate hydrogel upregulated the tissue expression levels of collagen type 1, collagen type 2, VEGF, b-FGF and TGF-B genes. This preclinical research, suggests potential use of FOE-loaded calcium alginate hydrogel system in treating diabetic wounds in the clinic.

Lignin-Cobalt Nano-Enabled Poly(pseudo)rotaxane Supramolecular Hydrogel for Treating Chronic Wounds

Chronic wounds (CWs) are a growing issue for the health care system. Their treatment requires a synergic approach to reduce both inflammation and the bacterial burden. In this work, a promising system for treating CWs was developed, comprising cobalt-lignin nanoparticles (NPs) embedded in a supramolecular (SM) hydrogel. First, NPs were obtained through cobalt reduction with phenolated lignin, and their antibacterial properties were tested against both Gram-negative and Gram-positive strains. The anti-inflammatory capacity of the NPs was proven through their ability to inhibit myeloperoxidase (MPO) and matrix metalloproteases (MMPs), which are enzymes involved in the inflammatory process and wound chronicity. Then, the NPs were loaded in an SM hydrogel based on a blend of α-cyclodextrin and custom-made poly(ether urethane)s. The nano-enabled hydrogel showed injectability, self-healing properties, and linear release of the loaded cargo. Moreover, the SM hydrogel's characteristics were optimized to absorb proteins when in contact with liquid, suggesting its capacity to uptake harmful enzymes from the wound exudate. These results render the developed multifunctional SM material an interesting candidate for the management of CWs.

Biomedical Applications of Electrets: Recent Advance and Future Perspectives

Recently, electrical stimulation, as a non-pharmacological physical stimulus, has been widely exploited in biomedical and clinical applications due to its ability to significantly enhance cell proliferation and differentiation. As a kind of dielectric material with permanent polarization characteristics, electrets have demonstrated tremendous potential in this field owing to their merits of low cost, stable performance, and excellent biocompatibility. This review provides a comprehensive summary of the recent advances in electrets and their biomedical applications. We first provide a brief introduction to the development of electrets, as well as typical materials and fabrication methods. Subsequently, we systematically describe the recent advances of electrets in biomedical applications, including bone regeneration, wound healing, nerve regeneration, drug delivery, and wearable electronics. Finally, the present challenges and opportunities have also been discussed in this emerging field. This review is anticipated to provide state-of-the-art insights on the electrical stimulation-related applications of electrets.

Development of an All-Marine 3D Printed Bioactive Hydrogel Dressing for Treatment of Hard-to-Heal Wounds

Current standard wound care involves dressings that provide moisture and protection; however, dressings providing active healing are still scarce and expensive. We aimed to develop an ecologically sustainable 3D printed bioactive hydrogel-based topical wound dressing targeting healing of hard-to-heal wounds, such as chronic or burn wounds, which are low on exudate. To this end, we developed a formulation composed of renewable marine components; purified extract from unfertilized salmon roe (heat-treated X, HTX), alginate from brown seaweed, and nanocellulose from tunicates. HTX is believed to facilitate the wound healing process. The components were successfully formulated into a 3D printable ink that was used to create a hydrogel lattice structure. The 3D printed hydrogel showed a HTX release profile enhancing pro-collagen I alpha 1 production in cell culture with potential of promoting wound closure rates. The dressing has recently been tested on burn wounds in Göttingen minipigs and shows accelerated wound closure and reduced inflammation. This paper describes the dressings development, mechanical properties, bioactivity, and safety.

Safety and Performance of Hemostatic Powders

Background

Hemorrhage, a sudden and severe leakage of blood due to the disruption of blood vessels, is one of the most common causes of death from injuries worldwide. Severe bleeding accounts for more than 35% of pre-hospital deaths and about 40% of deaths recorded within 24 hours of injury. One of the methods for achieving homeostasis is the use of hemostatic powders. This study compares the basic safety and performance of the most popular hemostatic powders.

Methods

Basic safety of commercially available products were evaluated using MTT, MEM elution assay, and endotoxin testing. The in vitro performance was evaluated using water absorption capacity, water absorption rate, and adhesion strength assays.

Results

4Seal, Starsil, and 4DryField extracts did not cause cytotoxicity in MTT and MEM elution assays. PerClot and SuperClot extracts demonstrated cytotoxic potential in MTT assay, while Arista extract was cytotoxic in both MEM elution and MTT assays. 4Seal has the lowest endotoxin contamination, followed by PerClot, 4DryField, SuperClot, Arista, and Starsil. 4Seal and Starsil showed significantly highest WAR among the tested samples, followed by 4DryField, Arista, PerClot, and SuperClot. Adhesion force is highest for 4Seal, followed by Starsil, PerClot, 4DryField Arista, and SuperClot.

Conclusion

4Seal is the most versatile in terms of safety and functional properties compared to 4DryField, Arista, PerClot, Starsil, and SuperClot.

Hydrogel-Based Biomaterial as a Scaffold for Gingival Regeneration: A Systematic Review of In Vitro Studies

BACKGROUND

Hydrogel is considered a promising scaffold biomaterial for gingival regeneration. In vitro experiments were carried out to test new potential biomaterials for future clinical practice. The systematic review of such in vitro studies could synthesize evidence of the characteristics of the developing biomaterials. This systematic review aimed to identify and synthesize in vitro studies that assessed the hydrogel scaffold for gingival regeneration.

METHODS

Data on experimental studies on the physical and biological properties of hydrogel were synthesized. A systematic review of the PubMed, Embase, ScienceDirect, and Scopus databases was conducted according to the Preferred Reporting System for Systematic Reviews and Meta-Analyses (PRISMA) 2020 statement guidelines. In total, 12 original articles on the physical and biological properties of hydrogels for gingival regeneration, published in the last 10 years, were identified.

RESULTS

One study only performed physical property analyses, two studies only performed biological property analyses, and nine studies performed both physical and biological property analyses. The incorporation of various natural polymers such as collagen, chitosan, and hyaluronic acids improved the biomaterial characteristics. The use of synthetic polymers faced some drawbacks in their physical and biological properties. Peptides, such as growth factors and arginine-glycine-aspartic acid (RGD), can be used to enhance cell adhesion and migration. Based on the available primary studies, all studies successfully present the potential of hydrogel characteristics in vitro and highlight the essential biomaterial properties for future periodontal regenerative treatment.

Efficacy of Flowable Collagen Hemostat Evaluated in Preclinical Models of Liver Injury and Spinal Cord Exposure

Introduction

Excessive bleeding in trauma and surgical settings leads to increased operative time, reoperation rates, and overall healthcare costs. A wide range of hemostatic agents have been developed to control bleeding that can vary considerably in type of hemostatic action, ease of application, cost, risk of infection, and dependence on patient coagulation. Microfibrillar collagen-based hemostatic materials (MCH) have yielded beneficial results in a variety of applications.

Methods

A new flowable collagen product, containing a modified MCH flour, but in a more convenient flowable delivery system, was evaluated for hemostatic efficacy in preclinical models of solid organ injury and spinal cord exposure. The primary objective of this study was to compare the hemostatic potential and local tissue responses to this novel, flowable collagen-based hemostatic agent to the original flour formulation to confirm that the new method of delivery did not interfere with the hemostatic properties of the MCH flour.

Results

When observed visually, the flowable MCH flour mixed with saline (FL) provided more precise application and uniform coverage to injured tissues compared to the dry MCH flour alone (F₀). All of the treatments (FL, F₀, and gauze) exhibited comparable Lewis bleed grade at all three time points evaluated in the capsular resection liver injury model (bleed grade: 1.0-1.3; p> 0.05 in all cases). FL and F₀ exhibited comparable 100% acute hemostatic efficacy and similar long-term histomorphological properties (up to 120 days) in a capsular resection liver injury in pigs, while gauze resulted in significantly lower rates of acute hemostatic efficacy (8-42%, p<0.05 in all cases). In an ovine model of dorsal laminectomy and durotomy, FL and F₀ again exhibited comparable results without any neurological effects.

Conclusion

Flowable microfibrillar collagen was shown to yield favorable short- and long-term outcomes in two representative applications where hemostatic efficacy is critical to surgical success.

Preparation of Biocompatible Manganese Selenium-Based Nanoparticles with Antioxidant and Catalytic Functions

The specificity of the tumor microenvironment (TME) severely limits the effectiveness of tumor treatment. In this study, we prepared a composite nanoparticle of manganese dioxide and selenite by a one-step redox method, and their stability under physiological conditions was improved with a bovine serum protein modification to obtain MnO₂/Se-BSA nanoparticles (SMB NPs). In the SMB NPs, manganese dioxide and selenite endowed the SMB NPs with acid-responsive and catalytic, and antioxidant properties, respectively. The weak acid response, catalytic activity, and antioxidant properties of composite nanoparticles were verified experimentally. Moreover, in an in vitro hemolysis assay, different concentrations of nanoparticles were incubated with mouse erythrocytes, and the hemolysis ratio was less than 5%. In the cell safety assay, the cell survival ratio was as high as 95.97% after the co-culture with L929 cells at different concentrations for 24 h. In addition, the good biosafety of composite nanoparticles was verified at the animal level. Thus, this study helps to design high-performance and comprehensive therapeutic reagents that are responsive to the hypoxia, weak acidity, hydrogen peroxide overexpression nature of TME and overcome the limitations of TME.

Preparation and Characterization of Biocompatible Iron/Zirconium/Polydopamine/Carboxymethyl Chitosan Hydrogel with Fenton Catalytic Properties and Photothermal Efficacy

In recent years, multifunctional hydrogel nanoplatforms for the synergistic treatment of tumors have received a great deal of attention. Here, we prepared an iron/zirconium/polydopamine/carboxymethyl chitosan hydrogel with Fenton and photothermal effects, promising for future use in the field of synergistic therapy and prevention of tumor recurrence. The iron (Fe)-zirconium (Zr)@ polydopamine (PDA) nanoparticles were synthesized by a simple one-pot hydrothermal method using iron (III) chloride hexahydrate (FeCl₃•6H₂O), zirconium tetrachloride (ZrCl₄), and dopamine, followed by activation of the carboxyl group of carboxymethyl chitosan (CMCS) using 1-(3-Dimethylaminopropyl)-3-ethylcarbodiimide hydrochloride (EDC)/N(4)-hydroxycytidine (NHS). Finally, the Fe-Zr@PDA nanoparticles and the activated CMCS were mixed to form a hydrogel. On the one side, Fe ions can use hydrogen peroxide (H₂O₂) which is rich in the tumor microenvironment (TME) to produce toxic hydroxyl radicals (•OH) and kill tumor cells, and Zr can also enhance the Fenton effect; on the other side, the excellent photothermal conversion efficiency of the incorporated PDA is used to kill tumor cells under the irradiation of near-infrared light. The ability of Fe-Zr@PDA@CMCS hydrogel to produce •OH and the ability of photothermal conversion were verified in vitro, and swelling and degradation experiments confirmed the effective release and good degradation of this hydrogel in an acidic environment. The multifunctional hydrogel is biologically safe at both cellular and animal levels. Therefore, this hydrogel has a wide range of applications in the synergistic treatment of tumors and the prevention of recurrence.

Development and In Vitro Analysis of Layer-by-Layer Assembled Membranes for Potential Wound Dressing: Electrospun Curcumin/Gelatin as Middle Layer and Gentamicin/Polyvinyl Alcohol as Outer Layers

Nanofibrous membranes made of hydrogels have high specific surface areas and are suitable as drug carriers. Multilayer membranes fabricated by continuous electrospinning could delay drug release by increasing diffusion pathways, which is beneficial for long-term wound care. In this experiment, polyvinyl alcohol (PVA) and gelatin were used as membrane substrates, and a sandwich PVA/gelatin/PVA structure of layer-by-layer membranes was prepared by electrospinning under different drug loading concentrations and spinning times. The outer layers on both sides were citric-acid-crosslinked PVA membranes loaded with gentamicin as an electrospinning solution, and the middle layer was a curcumin-loaded gelatin membrane for the study of release behavior, antibacterial activity, and biocompatibility. According to the in vitro release results, the multilayer membrane could release curcumin slowly; the release amount was about 55% less than that of the single layer within 4 days. Most of the prepared membranes showed no significant degradation during immersion, and the phosphonate-buffered saline absorption rate of the multilayer membrane was about five to six times its weight. The results of the antibacterial test showed that the multilayer membrane loaded with gentamicin had a good inhibitory effect on Staphylococcus aureus and Escherichia coli. In addition, the layer-by-layer assembled membrane was non-cytotoxic but detrimental to cell attachment at all gentamicin-carrying concentrations. This feature could be used as a wound dressing to reduce secondary damage to the wound when changing the dressing. This multilayer wound dressing could be applied to wounds in the future to reduce the risk of bacterial infection and help wounds heal.

An injectable hydrogel based on Bi2Se3 nanosheets and hyaluronic acid for chemo-photothermal synergistic therapy

To resolve poor accumulation caused by systemic administration, injectable and responsive hydrogels are the prospective drug delivery systems for localized tumor treatment, owning to negligible invasiveness and accurate administration. Herein, an injectable hydrogel, based on dopamine (DA) crosslinked hyaluronic acid and Bi₂Se₃ nanosheets (NSs) loading with doxorubicin (DOX) coated with polydopamine (Bi₂Se₃-DOX@PDA), was developed for synergistic chem-photothermal cancer therapy. The ultrathin functional Bi₂Se₃-DOX@PDA NSs could be responsive to the weak acidic condition and photothermal effect under NIR laser irradiation, achieving controlled release of DOX. Moreover, nanocomposite hydrogel based on hyaluronic acid matrix could be precisely administrated through intratumoral injection since its injectability and self-healing capacity, remaining at injected sites for at least 12 days. Furthermore, the excellent therapeutics effect of Bi₂Se₃-DOX@PDA nanocomposite hydrogel was demonstrated on 4 T1 xenograft tumor with outstanding injectability and negligible systemic side-effect. In short, the construction of Bi₂Se₃-DOX@PDA nanocomposite hydrogel paves a prospective path for local treatment of cancers.

Rapidly degrading and mussel-inspired multifunctional carboxymethyl chitosan/montmorillonite hydrogel for wound hemostasis

The conventional method of using montmorillonite hemostatic materials affects the hemostatic effect due to easy dislodgement on the wound surface. In this paper, a multifunctional bio-hemostatic hydrogel (CODM) was prepared based on hydrogen bonding and Schiff base bonding using modified alginate, polyvinylpyrrolidone (PVP), and carboxymethyl chitosan. The amino group-modified montmorillonite was uniformly dispersed in the hydrogel by its amido bond formation with the carboxyl groups of carboxymethyl chitosan and oxidized alginate. The catechol group, -CHO, and PVP can form hydrogen bonds with the tissue surface to afford the firm tissue adhesion to afford the wound hemostatic. The addition of montmorillonite-NH₂ further improves the hemostatic ability, making it even better than commercial hemostatic materials. Moreover, the photothermal conversion ability (derived from the polydopamine) was synergized with the phenolic hydroxyl group, quinone group, and the protonated amino group to effectively kill the bacteria in vitro and in vivo. Based on its in vitro and in vivo biosafety and satisfactory degradation ratio anti-inflammatory, antibacterial, and hemostatic properties, the CODM hydrogel holds promising potential for emergency hemostasis and intelligent wound management.

Regenerated silk fibroin based on small aperture scaffolds and marginal sealing hydrogel for osteochondral defect repair

BACKGROUND

Osteochondral defects pose an enormous challenge without satisfactory repair strategy to date. In particular, the lateral integration of neo-cartilage into the surrounding native cartilage is a difficult and inadequately addressed problem determining tissue repair's success.

METHODS

Regenerated silk fibroin (RSF) based on small aperture scaffolds was prepared with n-butanol innovatively. Then, the rabbit knee chondrocytes and bone mesenchymal stem cells (BMSCs) were cultured on RSF scaffolds, and after induction of chondrogenic differentiation, cell-scaffold complexes strengthened by a 14 wt% RSF solution were prepared for in vivo experiments.

RESULTS

A porous scaffold and an RSF sealant exhibiting biocompatibility and excellent adhesive properties are developed and confirmed to promote chondrocyte migration and differentiation. Thus, osteochondral repair and superior horizontal integration are achieved in vivo with this composite.

CONCLUSIONS

Overall, the new approach of marginal sealing around the RSF scaffolds exhibits preeminent repair results, confirming the ability of this novel graft to facilitate simultaneous regeneration of cartilage-subchondral bone.

Exploring the Potential of Royal-Jelly-Incorporated Hydrogel Dressings as Innovative Wound Care Materials

The development of multifunctional dressing materials with beneficial properties for wound healing has become a recent focus of research. Many studies are being conducted to incorporate active substances into dressings to positively impact wound healing processes. Researchers have investigated various natural additives, including plant extracts and apiproducts such as royal jelly, to enhance the properties of dressings. In this study, polyvinylpyrrolidone (PVP)-based hydrogel dressings modified with royal jelly were developed and analyzed for their sorption ability, wettability, surface morphology, degradation, and mechanical properties. The results showed that the royal jelly and crosslinking agent content had an impact on the physicochemical properties of the hydrogels and their potential for use as innovative dressing materials. This study investigated the swelling behavior, surface morphology, and mechanical properties of hydrogel materials containing royal jelly. The majority of the tested materials showed a gradual increase in swelling ratio with time. The pH of the incubated fluids varied depending on the type of fluid used, with distilled water having the greatest decrease in pH due to the release of organic acids from the royal jelly. The hydrogel samples had a relatively homogeneous surface, and no dependence between composition and surface morphology was observed. Natural additives like royal jelly can modify the mechanical properties of hydrogels, increasing their elongation percentage while decreasing their tensile strength. These findings suggest possible future applications in various fields requiring high flexibility and elasticity.

Optimization of sodium alginate-galactoxyloglucan blended hydrogel beads through ionotropic gelation method

Hydrogels are 3D crosslinking networks of hydrophilic biopolymers which can able to absorb and retain large amount of water. In this present study, the Sodium alginate (SA)- Galactoxyloglucan (GXG) blended hydrogel beads were prepared and optimized through two level optimization steps. Alginates and xyloglucan are the cell wall polysaccharides biopolymers obtained from the plant sources, Sargassum sp. and Tamarindus indica L. respectively. The extracted biopolymers were confirmed and characterized by UV-Spectroscopy, FT-IR, NMR and TGA analysis. Based on the hydrophilicity, non-toxicity and biocompatibility, SA-GXG hydrogel were prepared and optimized through two-level optimization steps. The optimized hydrogel bead formulation was characterized through FT-IR, TGA and SEM analysis. From the obtained result, it is found that the polymeric formulation GXG (2 % w/v)-SA (1.5 % w/v), cross-linker (CaCl₂) concentration at 0.1 M and the cross-linking time at 15 Min showed significant swelling index. The optimized hydrogel beads are porous and show good swelling capacity and thermal stability. The optimized protocol of hydrogel beads may be useful in designing hydrogel beads for specific applications in agricultural, Biomedical and remediation sectors.

Advances in Functional Hydrogel Wound Dressings: A Review

One of the most advanced, promising, and commercially viable research issues in the world of hydrogel dressing is gaining functionality to achieve improved therapeutic impact or even intelligent wound repair. In addition to the merits of ordinary hydrogel dressings, functional hydrogel dressings can adjust their chemical/physical properties to satisfy different wound types, carry out the corresponding reactions to actively create a healing environment conducive to wound repair, and can also control drug release to provide a long-lasting benefit. Although a lot of in-depth research has been conducted over the last few decades, very few studies have been properly summarized. In order to give researchers a basic blueprint for designing functional hydrogel dressings and to motivate them to develop ever-more intelligent wound dressings, we summarized the development of functional hydrogel dressings in recent years, as well as the current situation and future trends, in light of their preparation mechanisms and functional effects.

Design and characterization of adipose-derived mesenchymal stem cell loaded alginate/pullulan/hyaluronic acid hydrogel scaffold for wound healing applications

Recently, significant attention has been focused on the progression of skin equivalents to facilitate faster wound healing and thereby skin restoration. The main aim of this study was the design and characterization of a novel polysaccharide-based hydrogel scaffold by using alginate, pullulan, and hyaluronic acid polymers to provide an appropriate microenvironment to deliver Adipose-derived mesenchymal Stem Cells (ASC) in order to promote wound healing in an animal model. Characterization of synthesized hydrogel was done by using a field emission scanning electron microscope (FE-SEM), Fourier Transform-Infrared spectroscopy (FT-IR), and Differential Scanning Calorimetry (DSC). Also, contact angle analysis, the swelling and mechanical tests were performed. As a result of in vitro studies, cells can be attached, alive, and migrate through the prepared hydrogel scaffold. Finally, the therapeutic effect of the cell-seeded hydrogels was tested in the full-thickness animal wound model. Based on obtained results, the hydrogel-ASC treatment improved the healing process and accelerated wound closure.

pH-Sensitive Degradable Oxalic Acid Crosslinked Hyperbranched Polyglycerol Hydrogel for Controlled Drug Release

pH-sensitive degradable hydrogels are smart materials that can cleave covalent bonds upon pH variation, leading to their degradation. Their development led to many applications for drug delivery, where drugs can be released in a pH-dependent manner. Crosslinking hyperbranched polyglycerol (HPG), a biocompatible building block bearing high end-group functionality, using oxalic acid (OA), a diacid that can be synthesized from CO2 and form highly activated ester bonds, can generate this type of smart hydrogel. Aiming to understand the process of developing this novel material and its drug release for oral administration, its formation was studied by varying reactant stoichiometry, concentration and cure procedure and temperature; it was characterized regarding gel percent (%gel), swelling degree (%S), FTIR and thermal behavior; impregnated using ibuprofen, as a model drug, and a release study was carried out at pH 2 and 7. Hydrogel formation was evidenced by its insolubility, FTIR spectra and an increase in Td and Tg; a pre-cure step was shown to be crucial for its formation and an increase in the concentration of the reactants led to higher %gel and lower %S. The impregnation resulted in a matrix-encapsulated system; and the ibuprofen release was negligible at pH 2 but completed at pH 7 due to the hydrolysis of the matrix. A pH-sensitive degradable HPG-OA hydrogel was obtained and it can largely be beneficial in controlled drug release applications.