Hyaluronic acid-based dual network hydrogel with sustained release of platelet-rich plasma as a diabetic wound dressing

Biomaterial-based drug delivery strategies for oral mucosa

Drug therapy is a key field in modern medicine, and the optimization of its delivery method is crucial. Traditional methods are inherently limited by first-pass effects, high-risk adverse reactions, and patient compliance challenges, which significantly restrict the effectiveness and application potential of drugs. Oral mucosal drug delivery has become a minimally invasive and effective drug delivery strategy. The unique anatomical structure of the oral mucosa facilitates the rapid absorption of drugs into the systemic circulation, thus producing rapid therapeutic effects. However, a complex oral microenvironment and mucosal barrier impede drug absorption. Biomaterials have become an important driving force for the innovative development of oral medicine, owing to their unique and excellent properties. They are widely used for preventing, diagnosing, treating, and rehabilitating oral diseases. This review explores recent advancements in biomaterial-enabled oral mucosal drug delivery systems, analyzing key physiological factors and absorption barriers that impact therapeutic outcomes. Focusing on innovative material engineering strategies highlights significant progress in extending drug residence time and improving delivery precision within the oral cavity. Furthermore, the study identifies critical challenges in translating these advancements from research to clinical practice, emphasizing the need for solutions to bridge this gap.

Dual network construction strategy of starch and calcium alginate to prepare tapioca pearls with efficiently embedded gamma-aminobutyric acid

The supplementation of gamma aminobutyric acid (GABA) through food matrices such as tapioca pearls has gained consumer acceptance due to better palatability and digestive release. However, GABA can leak from the pearls during the cooking process. This study proposes a simple and cost-effective one-pot method where sodium alginate and calcium lactate are directly added to the tapioca starch matrix to form dual networks, reducing the cooking leakage rate from 36.27 % to 15.52 %. Furthermore, this method extends the sustained release time of GABA in the digestive tract. The microstructural analysis indicates that during the cooking process, sodium alginate and calcium lactate interact to form a calcium alginate gel network, which effectively fills the voids within the starch gel matrix, thereby reducing the leakage of small GABA molecules. This study also examined the effects of calcium alginate networks on starch matrix and the interactions between these two networks. The starch‑calcium alginate dual network reduced GABA leakage during the cooking process in tapioca pearls, while improving its sustained release during digestion. The present work provides a new approach to improving encapsulation and digestive release of small molecules and water-soluble nutrients.

Application of Platelet-Rich Plasma-Based Scaffolds in Soft and Hard Tissue Regeneration

Platelet-rich plasma (PRP) is a blood product with higher platelet concentrations than whole blood, offering controlled delivery of growth factors (GFs) for regenerative medicine. PRP plays pivotal roles in tissue restoration mechanisms, including angiogenesis, fibroblast proliferation, and extracellular matrix development, making it applicable across various regenerative medicine treatments. Despite promising results in different tissue injuries, challenges such as short half-life and rapid deactivation by proteases persist. To address these challenges, biomaterial-based delivery scaffolds, such as sponges or hydrogels, have been investigated. Current studies exhibit that PRP-loaded scaffolds fix these issues due to the sustained release of GFs. In this regard, given the widespread application of PRP in clinical studies, the use of PRP-loaded scaffolds has drawn significant consideration in tissue engineering (TE). Therefore, this review briefly introduces PRP as a rich origin of GFs, its classification, and preparation methods and discusses PRP applications in regenerative medicine. This study also emphasizes and reviews the latest research on the using scaffolds for PRP delivery in diverse fields of TE, including skin, bone, and cartilage repair.

State-of-the-art in natural hydrogel-based wound dressings: Design, functionalization, and fabrication approaches

Natural hydrogel-based wound dressings, synthesized from biopolymers such as chitosan, sodium alginate, and cellulose, are gaining recognition in wound care due to their ability to promote healing through biocompatibility, moisture retention, and biodegradability. These materials foster an ideal healing environment by supporting cell proliferation and tissue regeneration while providing a protective barrier against infection. For chronic or infected wounds, enhancing the therapeutic performance of these hydrogels is essential. This review critically evaluates advanced functionalization strategies, including chemical modifications to optimize hydrogel properties, the incorporation of bioactive agents like growth factors and antimicrobial compounds, and the development of stimuli-responsive hydrogels that adjust to environmental cues such as pH, temperature, and enzymatic activity. Furthermore, fabrication techniques-such as solution casting, freeze-drying, electrospinning, and 3D printing-are discussed for their potential to generate tailored dressings with specific mechanical properties and bioactive capabilities. By highlighting key innovations and challenges, this review provides a comprehensive roadmap for the design, functionalization, and fabrication of natural hydrogel-based wound dressings, identifying critical areas for future research and development.

Hyaluronic acid modified chuanxiong oil liposomes as a novel therapeutic agent for photoaging prevention

The gradual increase in ultraviolet B (UVB) health hazards to human skin, coupled with the irritation associated with existing sunscreen products, underscores the critical need for the development of natural sunscreens to combat UVB-induced photoaging. Chuanxiong oil (CXO) and hyaluronic acid (HA) possess excellent antioxidant and anti-apoptotic properties, which are closely linked to the mechanisms of photoaging. In this study, a composite nano-system (HA-CXO-Lip) comprising chuanxiong oil (CXO) and hyaluronic acid (HA) was initially fabricated. Subsequently, both in vitro HaCaT cell models and in vivo murine photoaging models were established to systematically evaluate the therapeutic efficacy and mechanistic actions of HA-CXO-Lip against photoaging under controlled experimental conditions. The investigation encompassed comprehensive assessments of its pharmacological effects and underlying molecular mechanisms through multimodal experimental approaches. Vitro experiments showed HA-CXO-Lip significantly reduced intracellular reactive oxygen species (ROS) levels and senescence-associated β-galactosidase (SA-β-Gal) activity. Furthermore, HA-CXO-Lip restored the levels of antioxidant enzymes, including superoxide dismutase (SOD), glutathione peroxidase (GSH-Px), catalase (CAT), and hydroxyproline (HYP), while also decreasing the levels of lipid metabolites such as 4-hydroxynonenal (4-HNE) and malondialdehyde (MDA). These findings indicate that HA-CXO-Lip effectively inhibits excessive oxidative stress. Additionally, HA-CXO-Lip inhibited apoptosis by reducing Bax levels and enhancing Bcl-2 expression in HaCaT cells. In vivo studies demonstrated that HA-CXO-Lip significantly reduced UVB irradiation-induced erythema and epidermal thickening in the backs of mice. It restored the orderly arrangement of collagen fibers and inhibited the activation of the core senescence pathway, AKT/mTOR, along with the downstream expression of matrix metalloproteinase 9 (MMP9), resulting in a decrease in collagen I disassembly. Additionally, HA-CXO-Lip was shown to significantly decrease the number of apoptotic cells, as indicated by the expression of the apoptosis marker cleaved cysteine aspartic protease-3 (C-Caspase-3) and the surface type I transmembrane glycoprotein (CD44), thereby further inhibiting apoptosis. The findings of this study suggest that HA-CXO-Lip can exert anti-photoaging effects through its antioxidant and anti-apoptotic properties, highlighting the synergistic efficacy of CXO and HA, which holds promise for the prevention and treatment of photoaging.

E-PL/MnO2 nanozymes/gellan gum/hyaluronic acid-based multifunctional hydrogel to promote diabetic wound healing

The development of multifunctional hydrogels, especially hydrogels with antibacterial and antioxidant properties, plays a crucial role in the effective healing of diabetic wounds. This work proposed a novel composite hydrogel with the oxidized gellan gum (O-GG) and hyaluronic acid (HA) as the hydrogel matrix, and the crosslinking was realized via the Ca2+. ε-polylysine/MnO2 nanozymes (EM) offered antioxidant and antibacterial properties to the corresponding composite hydrogels. The results verified that the O-GG/HA@EM hydrogel exhibited excellent cytocompatibility and injectability. The CCK-8 data indicated that the proliferation rate of mouse fibroblasts reached 314.58 % after three days of coculture with the hydrogel. The hydrogel effectively alleviated oxidative stress and hypoxic microenvironments in wounds, inhibited bacterial infection, and promoted angiogenesis, thereby significantly accelerating the healing process of diabetic wounds. Data from a mouse diabetic wound model revealed that the wound closure rate in the sample group reached 92.4 % after 14 days. This composite hydrogel provides a novel and effective solution for the treatment of chronic diabetic wounds.

Hyaluronic acid/ε-polylysine hydrogel enriched with Saussurea involucrata polysaccharide for improved skin dryness induced by ultraviolet radiation

Ultraviolet B (UVB) radiation exposure is a major contributor to skin photoaging, ultimately resulting in dryness. Conventional treatments for this condition frequently exhibit limited efficacy due to poor skin penetration and are associated with significant side effects. Saussurea involucrate polysaccharide (SIP) has been shown to alleviate photoaging-induced dry skin; however, its effectiveness is limited due to low drug utilization and the need for frequent dosing. In this study, we developed hyaluronic acid (HA) and ε-polylysine (ε-PLL) hydrogels designed to enhance skin hydration and enable sustained drug release. The optimal formulation, designated A5E3, contained 5 % HA plus 3 % ε-PLL. The sustained release of SIP from A5E3 demonstrated superior therapeutic effects in a mouse model of skin photoaging, including reduced inflammation and apoptosis, as well as enhanced keratinocyte differentiation and lipid production. The A5E3 hydrogel not only enhanced the drug utilization of SIP but also provided a sustained moisturizing environment, promoting faster skin repair. These findings support the development of skincare products with superior moisturizing and reparative properties, underscoring the potential of hydrogels as effective carriers for treating UVB-induced skin dryness and damage.

Development of hyaluronic acid-based hydrogels for chronic diabetic wound healing: A review

This research delves into the advancements in chronic skin wound treatment, with a particular focus on diabetic foot ulcers, utilizing hyaluronic acid (HA)-based hydrogels. Hyaluronic acid, an integral component of the skin's extracellular matrix, plays a crucial role in process such as inflammation, angiogenesis, and tissue regeneration. Due to their three-dimensional network structure, biocompatibility, hydrophilicity, and gas exchange capabilities, HA-based hydrogels are considered highly suitable for promoting wound healing. Nonetheless, pure HA hydrogels exhibit limitations including insufficient mechanical strength and rapid release of encapsulated substances. To address these limitations, the incorporation of bioactive materials such as chitosan and collagen was investigated. This combination not only optimized mechanical strength and degradation rates but also enhanced antibacterial and anti-inflammatory properties. Furthermore, responsive hydrogel dressings were developed to adapt to the specific characteristics of the diabetic wound microenvironment, enabling on-demand drug release. These advancements present new perspectives for the treatment of diabetic foot ulcers.

Blood Plasma, Fibrinogen or Fibrin Biomaterial for the Manufacturing of Skin Tissue-Engineered Products and Other Dermatological Treatments: A Systematic Review

The use of blood plasma, fibrinogen or fibrin, a natural biomaterial, has been widely studied for the development of different skin tissue-engineered products and other dermatological treatments. This systematic review reports the preclinical and clinical studies which use it alone or combined with other biomaterials and/or cells for the treatment of several dermatological conditions. Following the PRISMA 2020 Guidelines, 147 preclinical studies have revealed that the use of this biomaterial as a wound dressing or as a monolayer (one cell type) skin substitute are the preferred strategies, mainly for the treatment of excisional or surgical wounds. Moreover, blood plasma is mainly used alone although its combination with other biomaterials such as agarose, polyethylene glycol or collagen has also been reported to increase its wound healing potential. However, most of the 17 clinical reviewed evaluated its use for the treatment of severely burned patients as a wound dressing or bilayer (two cell types) skin substitute. Although the number of preclinical studies evaluating the use of blood plasma as a dermatological treatment has increased during the last fifteen years, this has not been correlated with a wide variety of clinical studies. Its safety and wound healing potential have been proved; however, the lack of a standard model and the presence of several approaches have meant that its translation to a clinical environment is still limited. A higher number of clinical studies should be carried out in the coming years to set a standard wound healing strategy for each dermatological disease.

Injectable Silver Nanoparticle-Based Hydrogel Dressings with Rapid Shape Adaptability and Antimicrobial Activity

Burns and scalds often result in deep wounds that challenge adequate debridement and inflammation control using traditional sheet-like hydrogel dressings. Herein, we developed an antibacterial, injectable, and self-healing hydrogel (ADCM@Ag) by employing carboxymethyl chitosan (CMCS) for in situ green reduction of silver ions and utilizing a spontaneous Schiff base reaction with aldehyde-functionalized dextran (AD). SEM analysis revealed a porous structure within the hydrogel. Swelling and enzymatic degradation assays demonstrated that ADCM@Ag hydrogel possesses excellent fluid absorption capacity and biodegradability. Mechanical tests indicated good mechanical properties, allowing the hydrogel to withstand external forces when applied to animal wounds. The hydrogel exhibited good injectability, shape adaptability, and self-healing capability. Cell experiments showed that the ADCM@Ag hydrogel avoided the cytotoxicity caused by high concentrations of silver ions and had good cell compatibility. Antimicrobial assays showed that ADCM@Ag exhibited potent bactericidal effects against Gram-negative and Gram-positive bacteria, achieving at least 85% killing efficacy. Collectively, ADCM@Ag hydrogel has good potential for wound dressing applications.

Current trends in the design and fabrication of PRP-based scaffolds for tissue engineering and regenerative medicine

Blood-derived biomaterials with high platelet content have recently emerged as attractive products for tissue engineering and regenerative medicine (TERM). Platelet-derived bioactive molecules have been shown to play a role in wound healing and tissue regeneration processes by promoting collagen synthesis, angiogenesis, cell proliferation, migration, and differentiation. Given their regenerative potential, platelet-rich blood derivatives have become a promising treatment option for use in a variety of conditions. Platelet-Rich Plasma (PRP), one of the platelet-rich blood derivatives, is a platelet concentrate suspended in a small volume of blood plasma obtained from whole blood. Due to its potential clinical benefits, PRP is widely used alone or in combination with various biomaterials/scaffolds in different fields of medicine and has shown promising results in wound healing. The recent growing interest in the development of PRP-based scaffolds also reveals new perspectives on the use of PRP or platelet lysate in TERM. This topical review contains a comprehensive summary of recent trends in the fabrication of PRP-based scaffolds that can deliver growth factors, serve as mechanical support for cells, and have therapeutic or regenerative properties. The article briefly focuses on diverse PRP-based constructs using PRP as a scaffolding material, their current fabrication approaches as well as the challenges encountered and provides a selection of existing strategies and new insights.

Recent advances in bioactive wound dressings

Traditional wound dressings, despite their widespread use, face limitations, such as poor infection control and insufficient healing promotion. To address these challenges, bioactive materials have emerged as a promising solution in wound care. This comprehensive review explores the latest developments in wound healing technologies, starting with an overview of the importance of effective wound management, emphasising the need for advanced bioactive wound dressings. The review further explores various bioactive materials, defining their characteristics. It covers a wide range of natural and synthetic biopolymers used to develop bioactive wound dressings. Next, the paper discusses the incorporation of bioactive agents into wound dressings, including antimicrobial and anti-inflammatory agents, alongside regenerative components like growth factors, platelet-rich plasma, platelet-rich fibrin and stem cells. The review also covers fabrication techniques for bioactive wound dressings, highlighting techniques like electrospinning, which facilitated the production of nanofibre-based dressings with controlled porosity, the sol-gel method for developing bioactive glass-based dressings, and 3D bioprinting for customised, patient-specific dressings. The review concludes by addressing the challenges and future perspectives in bioactive wound dressing development. It includes regulatory considerations, clinical efficacy, patient care protocol integration and wound healing progress monitoring. Furthermore, the review considers emerging trends such as smart materials, sensors and personalised medicine approaches, offering insights into the future direction of bioactive wound dressing research.

Licochalcone A loaded multifunctional chitosan hyaluronic acid hydrogel with antibacterial and inflammatory regulating effects to promote wound healing

The wound healing process is characterized by persistent infection and long-term inflammation. The licochalcone A (LicA) has the potential for skin wound healing and needs a good drug-loading platform to apply its antibacterial and anti-inflammatory effects. In this study, the LicA@chitosan (CS) -hyaluronic acid (HA) hydrogel with antibacterial and anti-inflammatory was developed for wound healing in mice. The SEM displayed that the hydrogel had an obvious porous structure and was very suitable to be used as a delivery carrier for LicA. The FTIR results suggested that the LicA can be effectively loaded in the CS-HA hydrogel. Variable strain scanning, frequency scanning and temperature scanning indicated that the LicA@CS-HA hydrogel can maintain the gel state. The LicA@CS-HA hydrogel had good biological safety, can inhibit the activity of Escherichia coli and Staphylococcus aureus, and can release LicA stably. The LicA@CS-HA hydrogel also has good adhesion and hemostatic properties. Finally, the LicA@CS-HA hydrogel significantly accelerated wound healing in mice skin injury model, and reduced inflammation and orderly collagen deposition were observed by HE and Masson staining. The immunohistochemistry indicated that the LicA@CS-HA hydrogel induced the positive expression of CD31, VEGF, and HIF-1α promoted neovascularization. The LicA@CS-HA hydrogel also down-regulated the expression of M1 macrophage markers CD86, IL-6, and TNF-α, and increased the expression of M2 macrophage markers CD206, IL-4, and IL-10 proteins. The molecular docking demonstrated that the target proteins had better binding activity to LicA. Collectively, the LicA@CS-HA hydrogel has broad application prospects in promoting wound healing.

Injectable and self-healable hydrogel based on pullulan polysaccharide loading platelet-rich plasma and metal-phenol network nanoparticles for infectious wound healing

Due to elevated glucose levels, oxidative stress, weakened immune function, and delayed angiogenesis, diabetic wounds are difficult to heal. However, current dressings often do not successfully achieve the desired therapeutic outcome for diabetic wounds. Platelet rich plasma (PRP) is widely used in the treatment of diabetic wounds. Even so, the sudden release of growth factors or proteins in PRP frequently hampers the therapeutic efficacy. Therefore, it is of considerable clinical value to achieve long-term release of active molecules in PRP and to create more effective diabetic wound dressings. Here, PRP was combined with pullulan polysaccharide derivatives (OPD) and polylysine derivatives (EPL-BA) to form a multifunctional hydrogel backbone. Tea polyphenols (TP), gallic acid (GA), and metal ions (Cu2+) were utilized to prepare metal-phenol network nanoparticles (TGMPN) which were encapsulated in the hydrogel system. The EPL-BA/OPD/PRP/TGMPN (EOPM) composite hydrogel showed injectable and self-healing properties. The hydrogel system could effectively remove reactive oxygen species (ROS) and showed excellent antibacterial properties against different bacteria. The results showed that EOPM hydrogel was effective in reducing the inflammatory response and promoting the regeneration of blood vessels and neoplastic tissues, thus greatly accelerating the repair of infected wounds.

Injectable GelMA Hydrogel Microspheres with Sustained Release of Platelet-Rich Plasma for the Treatment of Thin Endometrium

Platelet-rich plasma (PRP) intrauterine infusion has been demonstrated to be effective in treating thin endometrium and achieving pregnancy. However, the rapid release of growth factors limits its effectiveness in clinical applications, and thus, multiple intrauterine infusions are often required to achieve therapeutic efficacy. In this study, a GelMA hydrogel microsphere biomaterial is developed using droplet microfluidics to modify the delivery mode of PRP and thus prolong its duration of action. Its biocompatibility is confirmed through both in vivo and in vitro studies. Cell experiments show that PRP-loaded microspheres significantly enhance cell proliferation, migration, and angiogenesis. In vivo experiments show that the effects of PRP-loaded microspheres on repairing the endometrium and restoring fertility in mice could achieve the impact of triple PRP intrauterine infusions. Further mechanistic investigations reveal that PRP could facilitate endometrial repair by regulating the expression of E2Fs, a group of transcription factors. This study demonstrates that hydrogel microspheres could modify the delivery of PRP and prolong its duration of action, enabling endometrial repair and functional reconstruction. This design avoids repeated intrauterine injections of PRP in the clinic, reduces the number of patient visits, and provides a new avenue for clinical treatment of thin endometrium.

Polyphenol-mediated hyaluronic acid/tannic acid hydrogel with short gelation time and high adhesion strength for accelerating wound healing

Wound healing is a complex process involving a complicated interplay between numerous cell types and vascular systems. Hyaluronic acid (HA)-based hydrogel facilitates wound healing, and is involved in all processes. However, slow gelation speed and weak adhesion strength limit its ability to form a stable physical barrier quickly. Herein, we propose a HA-based composite hydrogel as the wound dressing based on oxidative coupling reaction. Tannic acid and dopamine-coated carbon particles (DCPs) containing abundant phenolic hydroxyl groups are incorporated into the HA-based hydrogel for increasing the number of crosslinking sites of oxidative coupling of the hydrogel and enhancing adhesion through the formation of covalent bonds and hydrogen bonds between hydrogel and wound sites. The composite hydrogel exhibits short gelation time (<6 s) and high adhesion strength (>8.1 kPa), which are superior to the references and commercial products of its kind. The in vitro experiments demonstrate that the hydrogel has low hemolytic reaction, negligible cytotoxicity, and the ability to promote fibroblast proliferation and migration. The in vivo full-thickness skin defect model experiments demonstrate that the hydrogel can accelerate wound healing under mild photothermal stimulation of DCPs by reducing inflammation, relieving tissue hypoxia, and promoting angiogenesis and epithelialization.

Developing fibrin-based biomaterials/scaffolds in tissue engineering

Tissue engineering technology has advanced rapidly in recent years, offering opportunities to construct biologically active tissues or organ substitutes to repair or even enhance the functions of diseased tissues and organs. Tissue-engineered scaffolds rebuild the extracellular microenvironment by mimicking the extracellular matrix. Fibrin-based scaffolds possess numerous advantages, including hemostasis, high biocompatibility, and good degradability. Fibrin scaffolds provide an initial matrix that facilitates cell migration, differentiation, proliferation, and adhesion, and also play a critical role in cell-matrix interactions. Fibrin scaffolds are now widely recognized as a key component in tissue engineering, where they can facilitate tissue and organ defect repair. This review introduces the properties of fibrin, including its composition, structure, and biology. In addition, the modification and cross-linking modes of fibrin are discussed, along with various forms commonly used in tissue engineering. We also describe the biofunctionalization of fibrin. This review provides a detailed overview of the use and applications of fibrin in skin, bone, and nervous tissues, and provides novel insights into future research directions for clinical treatment.

Application of autologous platelet-rich gel formed by calcium gluconate combined with hormone therapy for endometrial repair after hysteroscopic transcervical resection of adhesion surgery and successful pregnancy: case report and literature review

Introduction

Intrauterine adhesion (IUA), a common gynecological disease, is mainly caused by traumatic or infectious factors that lead to basal endometrial layer physiological repair disorders. IUA is mostly treated via hysteroscopic transcervical resection of adhesion and although it can restore uterine cavity shape, its endometrial repair effectiveness is limited. The figures showed that after surgery, patients with IUA have a high recurrence rate. Therefore, quick endometrial damage repair is key to successful treatment.

Case presentation

A 34-year-old patient visited our hospital after experiencing amenorrhea for 4 months following an induced abortion and had a fertility requirement. Based on the American Fertility Society intrauterine scores, the patient was diagnosed with moderate IUA. She underwent transcervical resection of adhesion, followed by autologous platelet-rich gel intrauterine perfusion and periodic estrogen-progesterone treatment for three menstrual cycles. No complications developed during treatment and the patient's endometrium was significantly repaired, with successful pregnancy being achieved.

Conclusion

Autologous platelet-rich gel promoted endometrial repair and acted as a mechanical barrier to prevent intrauterine adhesion. This approach May offer new insights into IUA treatment.

Locationally activated PRP via an injectable dual-network hydrogel for endometrial regeneration

Enhancing the effectiveness of platelet-rich plasma (PRP) for endometrial regeneration is challenging, due to its limited mechanical properties and burst release of growth factors. Here, we proposed an injectable interpenetrating dual-network hydrogel that can locationally activate PRP within the uterine cavity, sustained release growth factors and further address the insufficient therapeutic efficacy. Locational activation of PRP is achieved using the dual-network hydrogel. The phenylboronic acid (PBA) modified methacrylated hyaluronic acid (HAMA) dispersion chelates Ca2+ by carboxy groups and polyphenol groups, and in situ crosslinked with PRP-loaded polyvinyl alcohol (PVA) dispersion by dynamic borate ester bonds thus establishing the soft hydrogel. Subsequently, in situ photo-crosslinking technology is employed to enhance the mechanical performance of hydrogels by initiating free radical polymerization of carbon-carbon double bonds to form a dense network. The PRP-hydrogel significantly promoted the endometrial cell proliferation, exhibited strong pro-angiogenic effects, and down-regulated the expression of collagen deposition genes by inhibiting the TGF-β1-SMAD2/3 pathway in vitro. In vivo experiments using a rat intrauterine adhesion (IUA) model showed that the PRP-hydrogel significantly promoted endometrial regeneration and restored uterine functionality. Furthermore, rats treated with the PRP-hydrogel displayed an increase in the number of embryos, litter size, and birth rate, which was similar to normal rats. Overall, this injectable interpenetrating dual-network hydrogel, capable of locational activation of PRP, suggests a new therapeutic approach for endometrial repair.

Copper Ion-Inspired Dual Controllable Drug Release Hydrogels for Wound Management: Driven by Hydrogen Bonds

Bacterial infections and inflammation progression yield huge trouble for the management of serious skin wounds and burns. However, some hydrogel dressing exhibit poor wound-healing capabilities. Additionally, little information is given on the molecular theory of hydrogel gelation mechanisms and drug release performance from drug-polymer network in the water environment. Herein, cationic guar gum (CG) is first mixed with dipotassium glycyrrhizinate (DG), and then crosslinked Cu2+ to strengthen the mechanical strength followed by encapsulating mussel adhesive protein (MAP) as composite dressings. Intriguingly, CG-Cu2+ 0.5-DG10 possessed proper rheological properties and mechanical strength predominantly driven by strong CG-H2O-Cu2+ and Cu2+-CG hydrogen bonding interaction. Weak DG-CG hydrogen bonding only controlled DG release in the initial 4 h, while strong hydrogen bonding is the main force regulating the sustained release of Cu2+ within 48 h. The incorporation of MAP further loosened the tight crosslinking of CG-Cu2+ 0.5-DG10. The screened CG-Cu2+ 0.5-DG10/MAP possessed excellent self-healing, injectability, antibacterial, anti-inflammatory, cell proliferation-promotion activities with high biocompatibility. Therefore, CG-Cu2+ 0.5-DG10/MAP hydrogel expedited wound closure on S. aureus-infected full-thickness skin wound model and lowered necrosis progression to the unburned interspaces on a rat burn model. The results highlight the promising translational potential of Cu2+-inspired hydrogels for the management of burns and infected wounds.

Multifunctional hydrogels based on photothermal therapy: A prospective platform for the postoperative management of melanoma

Preventing the recurrence of melanoma after surgery and accelerating wound healing are among the most challenging aspects of melanoma management. Photothermal therapy has been widely used to treat tumors and bacterial infections and promote wound healing. Owing to its efficacy and specificity, it may be used for postoperative management of tumors. However, its use is limited by the uncontrollable distribution of photosensitizers and the likelihood of damage to the surrounding normal tissue. Hydrogels provide a moist environment with strong biocompatibility and adhesion for wound healing owing to their highly hydrophilic three-dimensional network structure. In addition, these materials serve as excellent drug carriers for tumor treatment and wound healing. It is possible to combine the advantages of both of these agents through different loading modalities to provide a powerful platform for the prevention of tumor recurrence and wound healing. This review summarizes the design strategies, research progress and mechanism of action of hydrogels used in photothermal therapy and discusses their role in preventing tumor recurrence and accelerating wound healing. These findings provide valuable insights into the postoperative management of melanoma and may guide the development of promising multifunctional hydrogels for photothermal therapy.

Harnessing the potential of hydrogels for advanced therapeutic applications: current achievements and future directions

The applications of hydrogels have expanded significantly due to their versatile, highly tunable properties and breakthroughs in biomaterial technologies. In this review, we cover the major achievements and the potential of hydrogels in therapeutic applications, focusing primarily on two areas: emerging cell-based therapies and promising non-cell therapeutic modalities. Within the context of cell therapy, we discuss the capacity of hydrogels to overcome the existing translational challenges faced by mainstream cell therapy paradigms, provide a detailed discussion on the advantages and principal design considerations of hydrogels for boosting the efficacy of cell therapy, as well as list specific examples of their applications in different disease scenarios. We then explore the potential of hydrogels in drug delivery, physical intervention therapies, and other non-cell therapeutic areas (e.g., bioadhesives, artificial tissues, and biosensors), emphasizing their utility beyond mere delivery vehicles. Additionally, we complement our discussion on the latest progress and challenges in the clinical application of hydrogels and outline future research directions, particularly in terms of integration with advanced biomanufacturing technologies. This review aims to present a comprehensive view and critical insights into the design and selection of hydrogels for both cell therapy and non-cell therapies, tailored to meet the therapeutic requirements of diverse diseases and situations.

A natural hydrogel complex improves intervertebral disc degeneration by correcting fatty acid metabolism and inhibiting nucleus pulposus cell pyroptosis

The degeneration of intervertebral discs is strongly associated with the occurrence of pyroptosis in nucleus pulposus (NP) cells. This pyroptosis is characterized by abnormal metabolism of fatty acids in the degenerative pathological state, which is further exacerbated by the inflammatory microenvironment and degradation of the extracellular matrix. In order to address this issue, we have developed a fibrin hydrogel complex (FG@PEV). This intricate formulation amalgamates the beneficial attributes of platelet extravasation vesicles, contributing to tissue repair and regeneration. Furthermore, this complex showcases exceptional stability, gradual-release capabilities, and a high degree of biocompatibility. In order to substantiate the biological significance of FG@PEV in intervertebral disc degeneration (IVDD), we conducted a comprehensive investigation into its potential mechanism of action through the integration of RNA-seq sequencing and metabolomics analysis. Furthermore, these findings were subsequently validated through experimentation in both in vivo and in vitro models. The experimental results revealed that the FG@PEV intervention possesses the capability to reshape the inflammatory microenvironment within the disc. It also addresses the irregularities in fatty acid metabolism of nucleus pulposus cells, consequently hindering cellular pyroptosis and slowing down disc degeneration through the regulation of extracellular matrix synthesis and degradation. As a result, this injectable gel system represents a promising and innovative therapeutic approach for mitigating disc degeneration.

Biomimetic design of platelet-rich plasma controlled release bacterial cellulose/hydroxyapatite composite hydrogel for bone tissue engineering

Bacterial cellulose (BC) hydrogel is renowned in the field of tissue engineering for its high biocompatibility, excellent mechanical strength, and eco-friendliness. Herein, we present a biomimetic mineralization method for preparing BC/hydroxyapatite (HAP) composite hydrogel scaffolds with different mineralization time and ion concentration of the mineralized solution. Spherical HAP reinforcement enhanced bone mineralization, thereby imparting increased bioactivity to BC matrix materials. Subsequently, platelet-rich plasma (PRP) was introduced into the scaffold. The PRP-loaded hydrogel enhanced the release of growth factors, which promoted cell adhesion, growth, and bone healing. After 3 weeks of MC3T3-E1 cell-induced osteogenesis, PRP positively affected cell differentiation in BC/HAP@PRP scaffolds. Overall, these scaffolds exhibited excellent biocompatibility, mineralized nodule formation, and controlled release in vitro, demonstrating great potential for application in bone tissue repair.

Multifunctional polypeptide-based hydrogel bio-adhesives with pro-healing activities and their working principles

Wound healing is a complex physiological process involving hemostasis, inflammation, proliferation, and tissue remodeling. Therefore, there is an urgent need for suitable wound dressings for effective and systematical wound management. Polypeptide-based hydrogel bio-adhesives offer unique advantages and are ideal candidates. However, comprehensive reviews on polypeptide-based hydrogel bio-adhesives for wound healing are still lacking. In this review, the physiological mechanisms and evaluation parameters of wound healing were first described in detail. Then, the working principles of hydrogel bio-adhesives were summarized. Recent advances made in multifunctional polypeptide-based hydrogel bio-adhesives involving gelatin, silk fibroin, fibrin, keratin, poly-γ-glutamic acid, ɛ-poly-lysine, serum albumin, and elastin with pro-healing activities in wound healing and tissue repair were reviewed. Finally, the current status, challenges, developments, and future trends of polypeptide-based hydrogel bio-adhesives were discussed, hoping that further developments would be stimulated to meet the growing needs of their clinical applications.

Polyhydroxy structure orchestrates the intrinsic antibacterial property of acrylamide hydrogel as a versatile wound-healing dressing

Hydrogel is considered as a promising candidate for wound dressing due to its tissue-like flexibility, good mechanical properties and biocompatibility. However, traditional hydrogel dressings often fail to fulfill satisfied mechanical, antibacterial, and biocompatibility properties simultaneously, due to the insufficient intrinsic bactericidal efficacy and the addition of external antimicrobial agents. In this paper, hydroxyl-contained acrylamide monomers, N-Methylolacrylamide (NMA) and N-[Tris (hydroxymethyl)methyl] acrylamide (THMA), are employed to prepare a series of polyacrylamide hydrogel dressings xNMA-yTHMA, where x and y represent the mass fractions of NMA and THMA in the hydrogels. We have elucidated that the abundance of hydroxyl groups determines the antibacterial effect of the hydrogels. Particularly, hydrogel 35NMA-5THMA exhibits excellent mechanical properties, with high tensile strength of 259 kPa and large tensile strain of 1737%. Furthermore, the hydrogel dressing 35NMA-5THMA demonstrates remarkable inherent antibacterial without exogenous antimicrobial agents owing to the existence of abundant hydroxyl groups. Besides, hydrogel dressing 35NMA-5THMA possesses excellent biocompatibility, in view of marginal cytotoxicity, low hemolysis ratio, and negligible inflammatory response and organ toxicity to mice during treatment. Encouragingly, hydrogel 35NMA-5THMA drastically promote the healing of bacteria-infected wound in mice. This study has revealed the importance of polyhydroxyl in the antibacterial efficiency of hydrogels and provided a simplified strategy to design wound healing dressings with translational potential.

ROS/pH dual responsive PRP-loaded multifunctional chitosan hydrogels with controlled release of growth factors for skin wound healing

Platelet-rich plasma (PRP) contains a variety of growth factors (GFs) and has been used in the treatment of a variety of diseases, including skin lesions. In particular, PRP with low immunogenicity will be more widely used. However, the explosive release of GFs limits its further application. In order to achieve controlled release of GFs, a multifunctional and reactive oxygen species (ROS)/pH dual responsive hydrogel was developed to load PRP derived from human cord blood for the treatment of skin wound healing. Based on the hydrogen bond and Schiff base interaction, carboxymethyl chitosan (CMCS), oxidized dextran (Odex) and oligomeric procyanidins (OPC) were crosslinked to form CMCS/Odex/OPC/PRP hydrogel with good injectability, self-healing, adhesion, ROS scavenging, antibacterial activity, controlled and sustained release of GFs. In vitro cell experiments suggested that this hydrogel possessed excellent biocompatibility and could promote the proliferation and migration of L929. In vivo healing of full-layer skin wounds further indicated that the prepared hydrogel could regulate inflammation and promote epithelialization, collagen deposition, and angiogenesis. In summary, this present study demonstrates that CMCS/Odex/OPC/PRP hydrogel may serve as a promising multifunctional dressing for skin wound healing.

Recent advances in biopolymer-based hydrogels and their potential biomedical applications

Hydrogels are three-dimensional networks of polymer chains containing large amounts of water in their structure. Hydrogels have received significant attention in biomedical applications owing to their attractive physicochemical properties, including flexibility, softness, biodegradability, and biocompatibility. Different natural and synthetic polymers have been intensely explored in developing hydrogels for the desired applications. Biopolymers-based hydrogels have advantages over synthetic polymers regarding improved cellular activity and weak immune response. These properties can be further improved by grafting with other polymers or adding nanomaterials, and they structurally mimic the living tissue environments, which opens their broad applicability. The hydrogels can be physically or chemically cross-linked depending on the structure. The use of different biopolymers-based hydrogels in biomedical applications has been reviewed and discussed earlier. However, no report is still available to comprehensively introduce the synthesis, advantages, disadvantages, and biomedical applications of biopolymers-based hydrogels from the material point of view. Herein, we systematically overview different synthesis methods of hydrogels and provide a holistic approach to biopolymers-based hydrogels for biomedical applications, especially in bone regeneration, wound healing, drug delivery, bioimaging, and therapy. The current challenges and prospects of biopolymers-based hydrogels are highlighted rationally, giving an insight into the progress of these hydrogels and their practical applications.

Advances in preparation and application of antibacterial hydrogels

Bacterial infections, especially those caused by drug-resistant bacteria, have seriously threatened human life and health. There is urgent to develop new antibacterial agents to reduce the problem of antibiotics. Biomedical materials with good antimicrobial properties have been widely used in antibacterial applications. Among them, hydrogels have become the focus of research in the field of biomedical materials due to their unique three-dimensional network structure, high hydrophilicity, and good biocompatibility. In this review, the latest research progresses about hydrogels in recent years were summarized, mainly including the preparation methods of hydrogels and their antibacterial applications. According to their different antibacterial mechanisms, several representative antibacterial hydrogels were introduced, such as antibiotics loaded hydrogels, antibiotic-free hydrogels including metal-based hydrogels, antibacterial peptide and antibacterial polymers, stimuli-responsive smart hydrogels, and light-mediated hydrogels. In addition, we also discussed the applications and challenges of antibacterial hydrogels in biomedicine, which are expected to provide new directions and ideas for the application of hydrogels in clinical antibacterial therapy.

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.