In Situ Synthesized Selenium Nanoparticles-Decorated Bacterial Cellulose/Gelatin Hydrogel with Enhanced Antibacterial, Antioxidant, and Anti-Inflammatory Capabilities for Facilitating Skin Wound Healing

A novel multifunctional self-assembled nanocellulose based scaffold for the healing of diabetic wounds

The healing of chronic diabetic wounds remains a key challenge due to its susceptibility to bacterial infection, the inflammatory wound microenvironment, and difficulty in angiogenesis. Herein, we devised a smart scaffold of nanocellulose with silk fibroin-loaded cerium oxide nanoparticles for the treatment of diabetic wounds. The smart scaffold dressing displays excellent porosity, water absorption, air permeability, water retention, controlled degradability, and antioxidant properties. In vitro experiments demonstrated that the scaffold was capable of promoting the degradation of the scaffolds through uncross linking and exhibited antibacterial activity against both Gram-positive (S. aureus) and Gram-negative (E. coli) bacteria. Furthermore, in vivo experiments showed that smart scaffold dressing can reduces inflammation at the wound site of diabetic mice and promote collagen deposition, angiogenesis and re-epithelialization during wound healing in diabetic mice, exhibiting favorable biocompatibility and biodegradability. Its efficacy surpassed that of the current commercially available membrane dressings (3 M dressings) and medical PELNAC dressings (Class III medical device). These findings suggest that the smart scaffold dressing is a promising and innovative dressing for the treatment of diabetic wounds.

Construction of AgNPs-loaded oriented hydrogel based on Periostracum Cicadae chitosan by electro-assembly for rapid hemostasis and wound healing

Oriented hydrogels have been recognized for their ability to promote cell proliferation and enhance wound repair. Chitosan, valued for its biocompatibility and biodegradability, is widely used in hydrogel preparation. However, chitosan derived from Periostracum Cicadae ("Chantui") has not been explored for creating antibacterial-oriented hydrogels. In this study, we successfully developed a Periostracum Cicadae chitosan-based oriented hydrogel (O-CH) using an electro-assembly method. The O-CH hydrogel exhibited superior hemostatic performance and mechanical strength, with stress levels 7.6 times higher than those of traditional alkali-neutralized hydrogels. Subsequently, silver nanoparticles (AgNPs) were formed in situ on the O-CH hydrogel without the need for additional reducing agents or stabilizers, yielding O-CH@Ag20, which exhibited excellent biocompatibility and enhanced antibacterial properties. In an S. aureus-infected full-thickness rat skin defect model, O-CH@Ag20 reduced bacterial counts at the wound site by 6-fold compared to the gauze group on day 3 and achieved a 97 % wound healing rate by day 10, versus 75 % in the gauze group. Histological analysis revealed that O-CH@Ag20 regulated angiogenesis, collagen deposition, and fibroblast differentiation into myofibroblasts, thereby accelerating wound contraction during remodeling. This study presents a novel approach to addressing clinical challenges in infected wound healing using Periostracum Cicadae chitosan-based antibacterial hydrogels.

Ultrasound-Driven Selenium Nanoparticles Realize Bone Defect Repair through Activating Selenoproteins to Regulate PI3K/AKT Signaling Pathway

Excessive and variable inflammation in bone defects is a key factor that impedes effective bone repair. Herein, an ultrasound-controlled composite hydrogel (LNT-SeNPs@Gel) integrating gelatin-methacryloyl and lentinan-decorated selenium nanoparticles (LNT-SeNPs) is developed, exhibiting strong antioxidant and anti-inflammatory properties to remodel the inflammatory microenvironment of bone defects. This hydrogel serves as a platform for integrating bifunctional ultrasound (ultrasound modulation, USc and ultrasound for repairing, USr), facilitating cascade treatment and reducing the overall treatment period. During the inflammatory phase of bone repair, USc remotely modulates the LNT-SeNPs@Gel hydrogel, regulating the release of LNT-SeNPs to inhibit the overproduction of reactive oxygen species (ROS) and inflammatory factors, ultimately remodeling the inflammatory microenvironment. Subsequently, USr could activate the phosphatidylinositol 3-kinase/protein kinase B (PI3K/AKT) signaling pathway regulated by selenoproteins to enhance the osteogenesis of MC3T3-E1 cells, thereby accelerating the bone repair process. Consequently, the combination of bifunctional ultrasound and LNT-SeNPs@Gel significantly improves bone repair outcomes and reduces the treatment period in rats. In conclusion, this study implies that the coordinated integration of the dual effects of ultrasound is a promising strategy for handling the complex and lengthy bone defects repair.

Construction and Performance Study of a Janus Dressing with Sustainable Drainage Function

In the field of wound exudate management, Janus dressings with unidirectional fluid transport capabilities have garnered extensive attention. However, the hydrophilic layer tends to be saturated during application, which often leads to significant declines in the drainage efficiency. To address this issue, this study constructed a Janus dressing with a hydrophilic-hydrophobic wettability gradient that could continuously evaporate the fluid in the hydrophilic layer. The hydrophilic nanofibers of poly(vinyl alcohol)-MXene (PVA-MXene) were deposited onto a hydrophobic nanofiber layer of polyurethane-MXene (PU-MXene) by sequential electrospinning to form a Janus dressing with asymmetric wettability. The dressing can enable unidirectional transport of exudate from the wound bed to the hydrophilic layer to effectively prevent the rewetting of the wound by the expelled biological fluid. The incorporation of MXene endows the dressing with photothermal responsiveness, allowing it to continuously expel exudate at a stable evaporation rate and maintain a moisture-unsaturated state. In addition, the photothermal effect imparts antibacterial activity to the dressing to prevent wound infections. In the application study using a rat wound infection model under NIR irradiation, the dressing demonstrated anti-inflammatory effects, promoted collagen deposition and angiogenesis, and thus significantly accelerated the wound healing process. Our study offered an innovative approach to the development of Janus structure dressings and provided an effective solution for wound exudate management.

Recent progress of multifunctional nanocellulose-based pharmaceutical materials: A review

In the pharmaceutical industry, ongoing research and development focus on discovering new drug formulations that align with regulatory approvals. Recently, innovative drug delivery systems have been used to maximize therapeutic efficacy with a precision of sustained drug delivery in the disease management system. Nanocellulose (NCs) synthesized from abundant cellulose, have attracted wide attention for potential pharmaceutical applications due to their unique properties, such as biocompatibility, high surface area-to-volume ratio, extensive drug loading and binding capacity, controlled drug release efficiency, strength, and availability with various treatments and modification ability. Nevertheless, research on nanocarriers (NCs) in the pharmaceutical field faces several limitations and challenges. Key areas requiring further exploration include chemical consumption, energy intensity, effluent management, recovery processes from acid hydrolysis, reaction times, ecotoxicology, and overall development progress. This overview provides the applications of emerging nanocellulose. It gives a clue on the synthesis of sustainable NCs related to their different sources, pre- and post-modifications of NCs, and key properties in pharmaceutical sectors. Furthermore, it gives an overview of the current advancements, life cycle analysis, biosafety, and key property performance with a summary of challenges and future perspectives.

Injectable carboxymethyl chitosan/konjac glucomannan/catechin hydrogel with free radical-scavenging, antimicrobial, and pro-healing abilities for infected wound repair

Wound management presents a significant clinical challenge, requiring advanced materials to support effective healing. This study reports the development of a multifunctional injectable hydrogel wound dressing (U-COC) composed of methacrylated carboxymethyl chitosan (CMCSMA), oxidized konjac glucomannan (OKGM), and (+)-catechin hydrate (CH). The formation of the U-COC hydrogel was driven by photo-initiated polymerization, dynamic reversible Schiff base bonds, and non-covalent forces (hydrogen bond interactions, π-π stacking, and hydrophobic interactions). The in vitro antioxidant and antimicrobial test results indicated that the U-COC hydrogel could effectively scavenge oxygen central free radical PTIO· (69.8 ± 0.3%) and nitrogen central free radical DPPH· (92.8 ± 0.7%), and exhibited excellent antimicrobial effects against E. coli (89.7 ± 3.9%) and S. aureus (91.4 ± 3.4%) due to the introduction of CH. Moreover, the as-designed hydrogel wound dressing was biosafe and biodegradable, demonstrating good adhesion, wound closure, self-healing properties, and shape adaptability. This hydrogel provided an advantageous microenvironment for cell proliferation, re-epithelialization, angiogenesis, collagen deposition, and tissue repair during infected wound healing. Therefore, the combination of CMCSMA, OKGM, and CH, along with the formation mechanism of the U-COC hydrogel, represents a novel advancement in wound management technology.

Selenium-Albumin Nanoaccelerator Hydrogel Promotes Wound Healing by Antibacterial, Anti-Inflammatory and Antioxidant along with Inhibits Scar Formation via Downregulating CD36

Wounds repairing after skin damage or diabetes remain a vast medical challenge, which often faces infection, inflammation, oxidative stress, and skin scarring. Herein, a multifunctional selenium-albumin nanoaccelerator hydrogel (H-Se NPs-Gel) is constructed based on the self-assembly of human serum albumin (HSA) with selenium nanoparticles (Se NPs) using carbomer as the carrier, it has remarkable antibacterial, anti-inflammatory, antioxidant and inhibits scarring properties than Se NPs for wound healing. Compared with Se NPs, H-Se NPs exhibit smaller particle sizes, exceptional stability, better antibacterial activity against common bacteria and MRSA, and superior antioxidant and anti-inflammatory capabilities in vitro without remarkable toxicity on skin cells. Importantly, it exhibits superior efficacy to Se NPs-Gel in accelerating the healing of full-thickness skin defects and diabetic wounds in mice. Interestingly, in a hypertrophic scar (HTS) model, H-Se NPs-Gel is more effective than Se NPs-Gel in inhibiting collagen formation to suppress scarring, which is mediated by the inhibition of CD36. The antagonistic effect of H-Se NPs on CD36 is also proved with the CD36 overexpression model. Furthermore, H-Se NPs-Gel demonstrates excellent safety in mice without systemic toxicity. H-Se NPs-Gel is an effective and safe therapy strategy for promoting wound healing and reducing scar formation in clinic.

Recent Trends in the Application of Cellulose-Based Hemostatic and Wound Healing Dressings

Rapid hemostasis and wound healing are crucial severe trauma treatment. Natural mechanisms often prove insufficient, spurring research for innovative biomaterials. This review focuses on cellulose-based materials, which are promising due to their absorbency, biocompatibility, and processability. The novelty lies in exploring how these materials promote clotting and tissue regeneration. They operate via extrinsic and intrinsic mechanisms. Extrinsically, they create a matrix at the wound to activate coagulation; intrinsically, they maintain clotting factors. Additionally, they aid healing through physical, chemical, and biological means, such as maintaining moisture, incorporating antimicrobial agents, and stimulating cell activity. The innovative fabrication strategies include material selection and chemical modification. Techniques like oxidation enhance performance. Structural engineering methods like freeze-drying and 3D printing optimize porosity and alignment. Cellulose-based dressings are versatile and effective in various forms. They address different wound needs and show benefits like rapid coagulation and tissue repair. This review also covers challenges and future trends, emphasizing the need to enhance mechanical properties and biodegradability. Further, new technologies offer potential improvements to the nanocomposites. Overall, continued research on cellulose-based dressing is vital, and unlocking their potential could revolutionize wound care, providing suitable solutions for trauma management.

Phycocyanin-based multifunctional hydrogel with self-healing, hemostatic, antioxidative, and antibacterial activity for wound healing

Hydrogels have gained significant attentions in the field of wound dressing since their resemblance to the extracellular matrix and excellent biocompatibility. Oxidative damage and bacterial infections resulting from an accumulation of reactive oxygen species (ROS) present significant challenges for chronic non-healing wounds. To address the issues of excessive ROS and bacterial infections during the wound healing process, we utilized C-phycocyanin, gelatin and silk fibroin as matrices to fabricate multifunctional hydrogels (PRG hydrogel), with rhein introduced as an antibacterial agent and tetracaine for pain relief. The hydrogel exhibited good stretchability, compressibility, and adhesion properties. Besides, the incorporation of dynamic covalent bonding endowed the hydrogels with good self-healing capabilities. The hydrogel exhibited good pro-coagulant hemostatic effects and favorable blood compatibility. Furthermore, the hydrogel possessed good antioxidant ability and can suppress S. aureus and P. aeruginosa. Additionally, the hydrogels showed high cytocompatibility and the rat trauma model further demonstrated that PRG-3 hydrogel could promote wound healing by reducing inflammation (TNF-α and IL-6) and accelerating collagen deposition and angiogenesis (CD31), which indicated that the hydrogel may as promise candidate for wound healing.

Bifunctional modified bacterial cellulose-based hydrogel through sequence-dependent crosslinking towards enhanced antibacterial and cutaneous wound healing

Chronic wounds caused by microbial infection have emerged as a major challenge on patients and medical health system. Bacterial cellulose (BC) characterized by its excellent biocompatibility and porous network, holds promise for addressing complex wound issues. However, lack of inherent antibacterial activity and cross-linking sites in the molecular network of BC have constrained its efficacy in hydrogel design and treatment of bacterial-infected wounds. Additionally, few studies have explored the effects of precursor crosslinking sequences on hydrogel processing. Herein, a quaternary ammonium and aldehyde-biofunctionalized bacterial cellulose (OQBC) was synthesized and utilized for the development of double network (DN) hydrogels, incorporating the crosslinking sequences of thiol-alginate (SASH) and carboxymethyl chitosan (CMCS). Firstly, OQBC was characterized with bifunctional groups, which endows its inherent antibacterial activity and gel-forming property. Subsequently, DN hydrogels formed through thiol-aldehyde addition and amino-aldehyde reactions showed favorable injectability and self-healing ability. The sequential crosslinking via Schiff-base and thiohemiacetal bonds endowed the hydrogels with distinct features, including degradation behavior, pH-responsive swelling, water retention, surface roughness, and cell behavior. With the increasing OQBC content into hydrogels, bacteriostatic rate exceeded 90 % without obvious cytotoxicity. Hydrogels also exhibited antioxidant and sustained drug release properties. Moreover, in infected skin thickness defect rats, the selected hydrogel enhanced wound repair and regeneration by inhibiting inflammation and promoting collagen deposition and angiogenesis. This design of sequence-dependent crosslinked antibacterial DN hydrogel offers a promising tool for the development of advanced materials to treat infected wounds.

On-demand imidazolidinyl urea-based tissue-like, self-healable, and antibacterial hydrogels for infectious wound care

Bacterial wound infections are a growing challenge in healthcare, posing severe risks like systemic infection, organ failure, and sepsis, with projections predicting over 10 million deaths annually by 2050. Antibacterial hydrogels, with adaptable extracellular matrix-like features, are emerging as promising solutions for treating infectious wounds. However, the antibacterial properties of most of these hydrogels are largely attributed to extrinsic agents, and their mechanisms of action remain poorly understood. Herein we introduce for the first time, modified imidazolidinyl urea (IU) as the polymeric backbone for developing tissue-like antibacterial hydrogels. As-designed hydrogels behave tissue-like mechanical features, outstanding antifreeze behavior, and rapid self-healing capabilities. Molecular dynamics (MD) simulation and density functional theory (DFT) calculation were employed to well-understand the extent of H-bonding and metal-ligand coordination to finetune hydrogels' properties. In vitro studies suggest good biocompatibility of hydrogels against mouse fibroblasts & human skin, lung, and red blood cells, with potential wound healing capacity. Additionally, the hydrogels exhibit good 3D printability and remarkable antibacterial activity, attributed to concentration dependent ROS generation, oxidative stress induction, and subsequent disruption of bacterial membrane. On top of that, in vitro biofilm studies confirmed that developed hydrogels are effective in preventing biofilm formation. Therefore, these tissue-mimetic hydrogels present a promising and effective platform for accelerating wound healing while simultaneously controlling bacterial infections, offering hope for the future of wound care.

Electricallymodified bacterial cellulose tailored with plant based green materials for infected wound healing applications

Effective treatment of infected wounds remains a challenge due to the rise of antibiotic-resistant microorganisms. The development of advanced materials with strong antimicrobial properties is necessary to address this issue. In this study, a unique composite of electrically modified bacterial cellulose (EBC) with allantoin (ABC) and zein was developed by dipping diffusion method. Morphological structural analysis revealed a uniform distribution of zein and aligned fibers, confirming the synthesis of the ABC-Zein composite. The formation of ABC-Zein was further confirmed by attenuated total reflection-Fourier transform infrared (ATR-FTIR), which displayed additional peaks corresponding to EBC, indicating the incorporation of zein into ABC. X-ray diffraction (XRD) analysis of ABC-Zein demonstrated a similar crystalline structure with EBC. The ABC-Zein showed mechanical integrity (tensile strength: 1.15 ± 0.21 MPa), thermal stability (degradation temperature: 290 °C), porous structure (porosity: 40.23 ± 0.21 %), and hydrophilic (water contact angle: 53.3 ± 5.3°) properties. Furthermore, the antimicrobial agent terpinen-4-ol (T4O), derived from tea tree oil, was incorporated into the ABC-Zein composite. Biological studies confirmed the antimicrobial efficacy (Staphylococcus aureus inhibition: 88.5 ± 7.19 %) and biocompatible (cell viability: 84.95 ± 5.6 %, hemolysis: 4.479 ± 0.39 %) nature of the T4O-ABC-Zein composite. The combined effects of the aligned fiber structure, zein protein, and antimicrobial T4O significantly enhanced infected wound healing by day 7, promoting inflammatory response, granular tissue formation, cell proliferation, and angiogenesis. By day 14, T4O-ABC-Zein facilitated complete wound healing, with reepithelization, collagen I deposition, and downregulation of CD 31, Ki67, and α-SMA. Overall, the innovative T4O-ABC-Zein composite, with an aligned fiber structure, improved biocompatibility, and antimicrobial properties, holds significant potential for the treatment of infected wounds.

Hydrogels and hydrogel-based drug delivery systems for promoting refractory wound healing: Applications and prospects

Refractory wounds represent a significant health concern that presents considerable challenges within clinical practice. The healing process of refractory wounds, which involves various cell types and biologically active molecules, is dynamically influenced by multiple factors, including diabetes, infections, and inflammation. Owing to their hydrophilicity, biocompatibility, and capacity for drug loading, hydrogels have emerged as promising and innovative biomaterials for enhancing wound healing. In recent decades, hydrogels with inherent therapeutic properties have been identified. Moreover, advanced hydrogel-based drug delivery systems have been developed to facilitate the sustained and controlled release of therapeutic agents at the site of refractory wounds. This review aims to summarize recent advancements and applications of hydrogels, including those with intrinsic therapeutic properties and hydrogel-based drug delivery systems, in the treatment of refractory wounds. Additionally, we discuss the limitations associated with hydrogel applications and propose future perspectives, which will lead to ongoing efforts to optimize hydrogels as ideal biomaterials for refractory wound healing.

Recent Trends in the Development and Application of Nano-Antioxidants for Skin-Related Disease

Skin is a vital barrier for the human body, protecting against external environmental influences and maintaining internal homeostasis. In addition, an imbalance of oxidative stress and antioxidant mechanisms can lead to skin-related diseases. Thus, for treating skin-related diseases, antioxidant therapy may be an important strategy to alleviate these symptoms. However, traditional drug therapies have limitations in treating these conditions, such as lack of lasting effect and insufficient skin permeability. Recently, nano-antioxidants, with their good permeability, sustained-release ability, multifunctionality, and other beneficial characteristics, have showed their advances in the exploration of skin-related diseases from research on safe therapies to clinical practice. Hereby, we review the latest research and advancements in nano-antioxidants for skin-related diseases. We categorize skin-related diseases into four main groups: skin inflammatory diseases, skin damage caused by ultraviolet rays, skin wound healing, and other skin-related conditions. Additionally, we summarize the prospects and potential future directions for nano-antioxidant drugs in treating skin-related diseases.

Copper doped carbon dots modified bacterial cellulose with enhanced antibacterial and immune regulatory functions for accelerating wound healing

The microenvironment of wound healing is susceptible to bacterial infection, chronic inflammation, oxidative stress, and inadequate angiogenesis, requiring the development of innovative wound dressings with antibacterial, anti-inflammatory, antioxidant, and angiogenic capabilities. This research crafted a new multifunctional bacterial cellulose composite membrane infused with copper-doped carbon dots (BC/Cu(II)-RCDs). Findings validated the successful loading of copper-doped carbon dots onto the BC membrane via hydrogen bonding interactions. Compared to the pure BC membrane, the BC/Cu(II)-RCDs composite membrane exhibited significantly enhanced hydrophilicity, tensile properties, and thermal stability. Diverse in vitro assays demonstrated excellent biocompatibility and antibacterial activity of BC/Cu(II)-RCDs composite membranes, alongside their ability to expedite the inflammatory phase and stimulate angiogenesis. In vivo trials corroborated the membrane's ability to foster epithelial regeneration, collagen deposition, and tissue regrowth in full-thickness skin wounds in rats while also curbing inflammation in infected full-thickness skin wounds. More importantly, the treatment of the BC/Cu(II)-RCDs composite membrane may result in the activation of VEGF and MAPK signaling proteins, which are key players in cell migration, angiogenesis, and skin tissue development. In essence, the developed BC/Cu(II)-RCDs composite membrane shows promise for treating infected wounds and serves as a viable alternative material for medicinal bandages.

Selenium Nanoparticles Suppressed Oxidative Stress and Promoted Tenocyte Marker Expression in Tendon-Derived Stem/Progenitor Cells

Traumatic tendon injuries generate reactive oxygen species and inflammation, which may account for slow or poor healing outcomes. Selenium is an essential trace element presented in selenoproteins, many of which are strong antioxidant enzymes. Selenium nanoparticles (SeNPs) have been reported to promote tissue repair due to their anti-oxidative, anti-inflammatory, anti-apoptotic, and differentiation-modulating properties. However, its effects on the functions of tendon-derived stem/progenitor cells (TDSCs) and tendon healing have not been reported. This study examined the effects of SeNPs on the functions of hydroperoxide (H2O2)-stimulated TDSCs. Rat patellar TDSCs were treated with H2O2 with or without SeNPs. The viability, marker of proliferation, oxidative stress, inflammation, apoptosis, and tenocyte marker expressions of H2O2-stimulated TDSCs after SeNPs treatment were assessed. Our results showed that SeNPs increased the viability and expression of the marker of proliferation of TDSCs exposed to H2O2, while concurrently reducing oxidative stress, inflammation, and apoptosis. Additionally, the expressions of tenocyte markers were significantly elevated in H2O2-treated TDSCs after treatment with SeNPs. Furthermore, the expressions of Sirt1 and Nrf2 also increased after SeNPs treatment in H2O2-stimulated TDSCs. In conclusion, SeNPs mitigated oxidative stress, inflammation, and apoptosis while enhancing the survival and expression of the marker of proliferation of TDSCs in an oxidative stress environment. Additionally, it promoted the fate of TDSCs towards the tenocyte lineage in the presence of such oxidative stress. The increased expressions of Sirt1 and Nrf2 likely mediated the anti-oxidative and anti-inflammatory effects of SeNPs. SeNPs hold promise as a novel intervention for promoting tendon healing.

Bacterial nanocelluloses as sustainable biomaterials for advanced wound healing and dressings

Wound healing remains a significant clinical challenge, calling for innovative approaches to expedite the recovery process and improve patient outcomes. Bacterial nanocelluloses (BNCs) have emerged as a promising solution in the field of wound healing and dressings due to their unique properties such as high crystallinity, mechanical strength, high purity, porosity, high water absorption capacity, biodegradability, biocompatibility, sustainability, and flexibility. BNC-based materials can be applied for the treatment of different types of wounds, from second-degree burns to skin tears, biopsy sites, and diabetic and ischemic wounds. BNC-based dressings have exceptional mechanical properties such as flexibility and strength, which ensure proper wound coverage and protection. The renewable nature, eco-friendly production process, longer lifespan, and potential for biodegradability of BNCs make them a more sustainable alternative to conventional wound care materials. This review aims to provide a detailed overview on the application of BNC-based composites for wound healing and dressings via highlighting their ability as a carrier for delivery of different types of antimicrobial compounds as well as their direct effect on the healing process. Besides, it mentions some of the in vivo and clinical studies using BNC-based dressings and describes challenges related to the application of these materials as well as their future directions.

Self-powered chitosan/graphene oxide hydrogel band-aids with bioadhesion for promoting infected wounds healing

Typical anti-infection strategies, such as antibiotics and other antibacterial nanomaterials, are effective in preventing bacterial infections during the wound healing process. Additionally, electrical stimulation (ES) can also inhibit bacterial growth and facilitate skin wound repair. However, self-powered and therapeutic wearable devices combining antibacterial materials with ES are still lacking. In this research, a bio-adhesive band-aid with antibacterial activity and piezoelectric properties made up of a chitosan/graphene oxide (CSGO) hydrogel matrix and a piezoelectric nanogenerator (PENG) patch based on electrospun polyvinylidene difluoride (PVDF) nanofibers is developed for promoting infected wounds healing. Specifically, self-adhesive CSGO hydrogels help the band-aid closely adhere to the wound site, and PVDF nanofibers convert biokinetic energy into electricity to provide real-time ES. The in vitro antibacterial test demonstrates that >99 % of S. aureus and E. coli are killed by the treatment of CSGO hydrogel and ES. Remarkably, in the rat model of infected wounds, the assembled band-aid consisting of a PENG of 2.25 cm2 can promote angiogenesis, collagen deposition, and re-epithelialization, greatly accelerating infected wounds healing in 21 days. This study offers a simple and practicable method for the design of wearable bioelectronics, indicating a promising future in personalized healthcare and clinical treatment.

Cellular and molecular roles of reactive oxygen species in wound healing

Wound healing is a highly coordinated spatiotemporal sequence of events involving several cell types and tissues. The process of wound healing requires strict regulation, and its disruption can lead to the formation of chronic wounds, which can have a significant impact on an individual's health as well as on worldwide healthcare expenditure. One essential aspect within the cellular and molecular regulation of wound healing pathogenesis is that of reactive oxygen species (ROS) and oxidative stress. Wounding significantly elevates levels of ROS, and an array of various reactive species are involved in modulating the wound healing process, such as through antimicrobial activities and signal transduction. However, as in many pathologies, ROS play an antagonistic pleiotropic role in wound healing, and can be a pathogenic factor in the formation of chronic wounds. Whilst advances in targeting ROS and oxidative stress have led to the development of novel pre-clinical therapeutic methods, due to the complex nature of ROS in wound healing, gaps in knowledge remain concerning the specific cellular and molecular functions of ROS in wound healing. In this review, we highlight current knowledge of these functions, and discuss the potential future direction of new studies, and how these pathways may be targeted in future pre-clinical studies.

Development of a cationic bacterial cellulose film loaded with anionic liposomes for prolonged release of oxacillin in wound dressing applications

Dressings should protect wounds, promote healing, absorb fluids, and maintain moisture. Bacterial cellulose is a biopolymer that stands out in biomaterials due to its high biocompatibility in several applications. In the area of dressings, it is already marketed as an alternative to traditional dressings. However, it lacks any intrinsic activity; among these, the need for antimicrobial activity in infected wounds stands out. We developed a cationic cellulose film by modifying cellulose with 1-(5-carboxypentyl)pyridin-1-ium bromide, enhancing its wettability (contact angle: 26.6°) and water retention capacity (2714.37 %). This modified film effectively retained oxacillin compared to the unmodified control. Liposomal encapsulation further prolonged oxacillin release up to 11 days. Both oxacillin-loaded films and liposomal formulations demonstrated antimicrobial activity against Staphylococcus aureus. Our findings demonstrate the potential of chemically modified cellulose as a platform for controlled anionic antibiotics and/or their formulations delivery in wound care.

Biological macromolecule-based hydrogels with antibacterial and antioxidant activities for wound dressing: A review

Because of the complex symptoms resulting from metabolic dysfunction in the wound microenvironment during bacterial infections, along with the necessity to combat free radicals, achieving prompt and thorough wound healing remains a significant medical challenge that has yet to be fully addressed. Moreover, the misuse of common antibiotics has contributed to the emergence of drug-resistant bacteria, underscoring the need for enhancements in the practical and commonly utilized approach to wound treatment. In this context, hydrogel dressings based on biological macromolecules with antibacterial and antioxidant properties present a promising new avenue for skin wound treatment due to their multifunctional characteristics. Despite the considerable potential of this innovative approach to wound care, comprehensive research on these multifunctional dressings is still insufficient. Consequently, the development of advanced biological macromolecule-based hydrogels, such as chitosan, alginate, cellulose, hyaluronic acid, and others, has been the primary focus of this study. These materials have been enriched with various antibacterial and antioxidant agents to confer multifunctional attributes for wound healing purposes. This review article aims to offer a comprehensive overview of the latest progress in this field, providing a critical theoretical basis for future advancements in the utilization of these advanced biological macromolecule-based hydrogels for wound healing.

Advances of biomacromolecule-based antibacterial hydrogels and their performance evaluation for wound healing: A review

Biomacromolecule hydrogels possess excellent mechanical properties and biocompatibility, but their inability to combat bacteria restricts their application in the biomedical field. With the increasing requirements and demands for hydrogel dressings, wound dressings with antibacterial properties of biomacromolecule hydrogels reinforced by adding antibacterial agents have attracted much attention, and related reviews are emerging. In this paper, the advances of biomacromolecule antibacterial hydrogels (including chitosan, sodium alginate, Hyaluronic acid, cellulose and gelatin) were first overviewed, and the antibacterial agents incorporated into hydrogels were classified (including metals and their derivatives, carbon-based materials, and native compounds). A series of performance evaluations of antibacterial hydrogels in the process of promoting wound healing were then reviewed, including basic properties (mechanical, rheological, injectable and self-healing, etc.), in vitro experiments (hemostasis, antibacterial, anti-inflammatory, anti-oxidation, biocompatibility) and in vivo experiments (in vivo model, histomorphology analysis, cytokines). Finally, the future development of biomacromolecule-based antibacterial hydrogels for wound healing is prospected. This work can provide a useful reference for researchers to prepare practical new wound hydrogel dressings.

Tunicate cellulose nanocrystals strengthened injectable stretchable hydrogel as multi-responsive enhanced antibacterial wound dressing for promoting diabetic wound healing

The intricate microenvironment of diabetic wounds characterized by hyperglycemia, intense oxidative stress, persistent bacterial infection and complex pH fluctuations hinders the healing process. Herein, an injectable multifunctional hydrogel (QPTx) was developed, which exhibited excellent mechanical performance and triple responsiveness to pH, temperature, and glucose due to dynamic covalent cross-linking involving dynamic Schiff base bonds and phenylboronate esters with phenylboronic-modified quaternized chitosan (QCS-PBA), polydopamine coated tunicate cellulose crystals (PDAn@TCNCs) and polyvinyl alcohol (PVA). Furthermore, the hydrogels can incorporate insulin (INS) drugs to adapt to the complex and variable wound environment in diabetic patients for on-demand drug release that promote diabetic wound healing. Based on various excellent properties of the colloidal materials, the hydrogels were evaluated for self-healing, rheological and mechanical properties, in vitro insulin response to pH/temperature/glucose release, antibacterial, antioxidant, tissue adhesion, coagulation, hemostasis in vivo and in vitro, and biocompatibility and biodegradability. By introducing PDAn@TCNCs particles, the hydrogel has photothermal antibacterial activity, enhanced adhesion and oxidation resistance. We further demonstrated that these hydrogel dressings significantly improved the healing process compared to commercial dressings (Tegaderm™) in full-layer skin defect models. All indicated that the glucose-responsive QPTx hydrogel platform has great potential for treating diabetic wounds.

The Role of Nanoparticles in Accelerating Tissue Recovery and Inflammation Control in Physiotherapy Practices

Physiotherapy has significantly evolved since its inception in the late 19th century, expanding into various specializations such as sports, neurology, and wound care. Its primary goal is to restore or enhance bodily functions through therapeutic interventions, aiding in conditions ranging from injuries to chronic pain. Tissue recovery, which involves repair and regeneration, is a critical aspect of physiotherapy. This natural process is influenced by factors like inflammation and injury severity. Nanotechnology, a relatively recent advancement, has transformed medicine, including wound care, through innovations in drug delivery, diagnostics, and anti-inflammatory treatments. Nanoparticles, owing to their small size and enhanced bioavailability, play a crucial role in improving drug delivery, increasing the efficacy of treatments, and promoting faster recovery. In the context of tissue healing, nanoparticles aid in cell proliferation, inflammation control, and scar reduction, among other therapeutic benefits. They are increasingly used in physiotherapy applications, to support tissue regeneration and inflammation management. This review examines the role of nanoparticles in physiotherapy, with a focus on their application in wound healing, muscle recovery, and inflammation control. It discusses various in-vitro and in-vivo studies that have explored the therapeutic potential of nanoparticles in these domains, providing insights into their mechanisms of action and effectiveness in promoting tissue regeneration and managing inflammation in physiotherapy settings.

Lysozyme-enhanced cellulose nanofiber, chitosan, and graphene oxide multifunctional nanocomposite for potential burn wound healing applications

The demand for advanced biomaterials in medical treatments is rapidly expanding. To address this demand, a nanocomposite of cellulose nanofiber (CNF) with chitosan (Ch) and graphene oxide (GO) was developed for burn wound treatment. The CNF-Ch-GO nanocomposites were characterized and their biological properties were evaluated. Microscopic images showed a uniform distribution of CNF, Ch, and GO with a porous structure. ATR-FTIR and XRD analyses confirmed the chemical structures, while a thermogravimetric study confirmed the stability of CNF-Ch-GO nanocomposite under a N2 atmosphere. The synthesized CNF-Ch-GO nanocomposite exhibited rapid absorption, absorbing 1781.7 ± 53.7 % PBS in 2 min. It demonstrated a Young's modulus of 11.90 ± 0.06 MPa in a hydrated condition, indicating its mechanical stability in water. Furthermore, it displayed excellent biocompatibility and hemocompatibility with 96.23 ± 12.21 % cell viability and 0.21 ± 0.08 % of hemolysis. Additionally, the blood clotting index of CNF-Ch-GO was comparable to that of standard dressing gauze. To enhance antimicrobial efficacy, CNF-Ch-GO was conjugated with lysozyme. This biotic and abiotic conjugation resulted in 92.17 % ± 3.02 % and 94.99 ± 2.1 % eradication of Escherichia coli and Staphylococcus aureus, respectively. The enhanced antimicrobial properties, biocompatibility, and mechanical stability of the superabsorbent CNF-Ch-GO nanocomposite indicate its significant potential for advanced burn wound healing applications.

Biosynthesis of positively charged bacterial cellulose hydrogel with antibacterial and anti-inflammatory function for efficient wound healing

In bacterial cellulose (BC)-based living materials, the effective and permanent incorporation of bactericidal agents into BC remains a persistent challenge. In this study, midazole quaternary ammonium salt was grafted onto a dispersion of bacterial cellulose, which was subsequently directly added to the fermentation medium of BC-producing bacteria to obtain BC-based hydrogel materials (BC/BC-[PQVI]Br) with inherent antibacterial properties. The BC/BC-[PQVI]Br hydrogel prepared in this study exhibits favorable tensile properties, with a maximum tensile stress of 970 KPa and water retention for up to 6 h. Moreover, it demonstrates acceptable antibacterial activity against S. aureus (93 %) and E. coli (71 %), respectively. Additionally, the hydrogel displays a high cell survival rate of 98 % after contact with NIH 3T3 cells, indicating its non-cytotoxic nature. Furthermore, the mouse wound experiment confirms the excellent wound healing effect of the hydrogel. This research presents an innovative approach towards developing environmentally friendly active wound dressings with microbial-derived antibacterial functionality.

Advancements of Biomacromolecular Hydrogel Applications in Food Nutrition and Health

Hydrogels exhibit remarkable degradability, biocompatibility and functionality, which position them as highly promising materials for applications within the food and pharmaceutical industries. Although many relevant studies on hydrogels have been reported in the chemical industry, materials, and other fields, there have been few reviews on their potential applications in food nutrition and human health. This study aims to address this gap by reviewing the functional properties of hydrogels and assessing their value in terms of food nutrition and human health. The use of hydrogels in preserving bioactive ingredients, food packaging and food distribution is delved into specifically in this review. Hydrogels can serve as cutting-edge materials for food packaging and delivery, ensuring the preservation of nutritional activity within food products, facilitating targeted delivery of bioactive compounds and regulating the digestion and absorption processes in the human body, thereby promoting human health. Moreover, hydrogels find applications in in vitro cell and tissue culture, human tissue repair, as well as chronic disease prevention and treatment. These broad applications have attracted great attention in the fields of human food nutrition and health. Ultimately, this paper serves as a valuable reference for further utilization and exploration of hydrogels in these respective fields.

Biotechnology in Food Packaging Using Bacterial Cellulose

Food packaging, which is typically made of paper/cardboard, glass, metal, and plastic, is essential for protecting and preserving food. However, the impact of conventional food packaging and especially the predominant use of plastics, due to their versatility and low cost, bring serious environmental and health problems such as pollution by micro and nanoplastics. In response to these challenges, biotechnology emerges as a new way for improving packaging by providing biopolymers as sustainable alternatives. In this context, bacterial cellulose (BC), a biodegradable and biocompatible material produced by bacteria, stands out for its mechanical resistance, food preservation capacity, and rapid degradation and is a promising solution for replacing plastics. However, despite its advantages, large-scale application still encounters technical and economic challenges. These include high costs compared to when conventional materials are used, difficulties in standardizing membrane production through microbial methods, and challenges in optimizing cultivation and production processes, so further studies are necessary to ensure food safety and industrial viability. Thus, this review provides an overview of the impacts of conventional packaging. It discusses the development of biodegradable packaging, highlighting BC as a promising biopolymer. Additionally, it explores biotechnological techniques for the development of innovative packaging through structural modifications of BC, as well as ways to optimize its production process. The study also emphasizes the importance of these solutions in promoting a circular economy within the food industry and reducing its environmental impact.

A Highly Stable, Multifunctional Janus Dressing for Treating Infected Wounds

The limited and unstable absorption of excess exudate is a major challenge during the healing of infected wounds. In this study, a highly stable, multifunctional Janus dressing with unidirectional exudate transfer capacity is fabricated based on a single poly(lactide caprolactone) (PLCL). The success of this method relies on an acid hydrolysis reaction that transforms PLCL fibers from hydrophobic to hydrophilic in situ. The resulting interfacial affinity between the hydrophilic/phobic PLCL fibers endows the Janus structure with excellent unidirectional liquid transfer and high structural stability against repeated stretching, bending, and twisting. Various other functions, including wound status detection, antibacterial, antioxidant, and anti-inflammatory properties, are also integrated into the dressing by incorporating phenol red and epigallocatechin gallate. An in vivo methicillin-resistant Staphylococcus aureus-infected wound model confirms that the Janus dressing, with the capability to remove exudate from the infected site, not only facilitates epithelialization and collagen deposition, but also ensures low inflammation and high angiogenesis, thus reaching an ideal closure rate up to 98.4% on day 14. The simple structure, multiple functions, and easy fabrication of the dressing may offer a promising strategy for treating chronic wounds, rooted in the challenges of bacterial infection, excessive exudate, and persistent inflammation.

Current progress of protein-based dressing for wound healing applications - A review

Protein-based wound dressings have garnered increasing interest in recent years owing to their distinct physical, chemical, and biological characteristics. The intricate molecular composition of proteins gives rise to unique characteristics, such as exceptional biocompatibility, biodegradability, and responsiveness, which contribute to the promotion of wound healing. Wound healing is an intricate and ongoing process influenced by multiple causes, and it consists of four distinct phases. Various treatments have been developed to repair different types of skin wounds, thanks to advancements in medical technology and the recognition of the diverse nature of wounds. This review has literature reviewed within the last 3-5 years-the recent progress and development of protein in wound dressings and the fundamental properties of an ideal wound dressing. Herein, the recent strides in protein-based state-of-the-art wound dressing emphasize the significant challenges and summarize future perspectives for wound healing applications.

Multifunctional Microneedle Patch with Diphlorethohydroxycarmalol for Potential Wound Dressing

BACKGROUND

Treatment of skin wounds with diverse pathological characteristics presents significant challenges due to the limited specific and efficacy of current wound healing approaches. Microneedle (MN) patches incorporating bioactive and stimulus materials have emerged as a promising strategy to overcome these limitations and integrating bioactive materials with anti-bacterial and anti-inflammatory properties for advanced wound dressing.

METHODS

We isolated diphlorethohydroxycarmalol (DPHC) from Ishige okamurae and assessed its anti-inflammatory and anti-bacterial effects on macrophages and its antibacterial activity against Cutibacterium acnes. Subsequently, we fabricated polylactic acid (PLA) MN patches containing DPHC at various concentrations (0-0.3%) (PDPHC MN patches) and evaluated their mechanical properties and biological effects using in vitro and in vivo models.

RESUTLS

Our findings demonstrated that DPHC effectively inhibited nitric oxide production in macrophages and exhibited rapid bactericidal activity against C. acnes. The PDPHC MN patches displayed potent antibacterial effects without cytotoxicity. Moreover, in 2,4-Dinitrochlorobenzene-stimulated mouse model, the PDPHC MN patches significantly suppressed inflammatory response and cutaneous lichenification.

CONCLUSION

The results suggest that the PDPHC MN patches holds promise as a multifunctional wound dressing for skin tissue engineering, offering antibacterial properties and anti-inflammatory properties to promote wound healing process.

Non-releasing poly (ionic liquid) based hydrogel accelerates diabetic wound healing

Persistent bacterial colonization, abnormal inflammatory responses, and impaired angiogenesis pose significant challenges to effective wound repair, particularly in diabetic wounds. Employing exogenous bioactive substances in wound dressings is a recognized approach to dynamically respond to the wound microenvironment and accelerate the repair process. However, this strategy can lead to the development of drug resistance and induce further tissue damage. To address these challenges, we are synthesizing a novel hydrogel for diabetic wound treatment using functional poly (ionic liquid) and modified dextran. The hydrogel is characterized by its excellent tissue adhesion, exceptional self-healing capacity, and substantial compressive deformation. It exhibits broad antibacterial activity, reduces the expression of pro-inflammatory cytokines and enhances the healing in diabetic wounds. Its efficacy is superior to that of the positive control group. This innovative non-releasing hydrogel presents as a promising alternative to conventional antibiotics, offering significant potential for the treatment and healing of diabetic chronic wounds.

Unveiling Green Synthesis and Biomedical Theranostic paradigms of Selenium Nanoparticles (SeNPs) - A state-of-the-art comprehensive update

The advancements in nanotechnology, pharmaceutical sciences, and healthcare are propelling the field of theranostics, which combines therapy and diagnostics, to new heights; emphasizing the emergence of selenium nanoparticles (SeNPs) as versatile theranostic agents. This comprehensive update offers a holistic perspective on recent developments in the synthesis and theranostic applications of SeNPs, underscoring their growing importance in nanotechnology and healthcare. SeNPs have shown significant potential in multiple domains, including antioxidant, anti-inflammatory, anticancer, antimicrobial, antidiabetic, wound healing, and cytoprotective therapies. The review highlights the adaptability and biocompatibility of SeNPs, which are crucial for advanced disease detection, monitoring, and personalized treatment. Special emphasis is placed on advancements in green synthesis techniques, underscoring their eco-friendly and cost-effective benefits in biosensing, diagnostics, imaging and therapeutic applications. Additionally, the appraisal scrutinizes the progressive trends in smart stimuli-responsive SeNPs, conferring their role in innovative solutions for disease management and diagnostics. Despite their promising therapeutic and prophylactic potential, SeNPs also present several challenges, particularly regarding toxicity concerns. These challenges and their implications for clinical translation are thoroughly explored, providing a balanced view of the current state and prospects of SeNPs in theranostic applications.

A Se Nanoparticle/MgFe-LDH Composite Nanosheet as a Multifunctional Platform for Osteosarcoma Eradication, Antibacterial and Bone Reconstruction

Despite advances in treating osteosarcoma, postoperative tumor recurrence, periprosthetic infection, and critical bone defects remain critical concerns. Herein, the growth of selenium nanoparticles (SeNPs) onto MgFe-LDH nanosheets (LDH) is reported to develop a multifunctional nanocomposite (LDH/Se) and further modification of the nanocomposite on a bioactive glass scaffold (BGS) to obtain a versatile platform (BGS@LDH/Se) for comprehensive postoperative osteosarcoma management. The uniform dispersion of negatively charged SeNPs on the LDH surface restrains toxicity-inducing aggregation and inactivation, thus enhancing superoxide dismutase (SOD) activation and superoxide anion radical (·O2 -)-H2O2 conversion. Meanwhile, Fe3+ within the LDH nanosheets can be reduced to Fe2+ by depleting glutathione (GSH) in the tumor microenvironments (TME), which can catalyze H2O2 into highly toxic reactive oxygen species. More importantly, incorporating SeNPs significantly promotes the anti-bacterial and osteogenic properties of BGS@LDH/Se. Thus, the developed BGS@LDH/Se platform can simultaneously inhibit tumor recurrence and periprosthetic infection as well as promote bone regeneration, thus holding great potential for postoperative "one-stop-shop" management of patients who need osteosarcoma resection and scaffold implantation.

Advancements in employing two-dimensional nanomaterials for enhancing skin wound healing: a review of current practice

The two-dimensional nanomaterials are characterized by their ultra-thin structure, diverse chemical functional groups, and remarkable anisotropic properties. Since its discovery in 2004, graphene has attracted significant scientific interest due to its potential applications in various fields, including electronics, energy systems, and biomedicine. In medicine, graphene is used for designing smart drug delivery systems, especially for antibiotics, and biosensing. Skin trauma is a prevalent dermatological condition that increasingly contributes to morbidities and mortalities, thus representing a significant health burden. During tissue damage, rapid skin repair is crucial to prevent blood loss and infection. Therefore, drugs used for skin trauma must possess antimicrobial and anti-inflammatory properties. Two-dimensional (2D) nanomaterials possess remarkable physical, chemical, optical, and biological characteristics due to their uniform shape, increased surface area, and surface charge. Graphene and its derivatives, transition-metal dichalcogenides (TMDs), black phosphorous (BP), hexagonal boron nitride (h-BN), MXene, and metal-organic frameworks (MOFs) are among the commonly used 2D nanomaterials. Moreover, they exhibit antibacterial and anti-inflammatory properties. This review presents a comprehensive discussion of the clinical approaches employed for wound healing treatment and explores the applications of commonly used 2D nanomaterials to enhance wound healing outcomes.

Robust Gradient Hydrogel-Loaded Nanofiber Fleshy Artificial Skin Via A Coupled Microfluidic Electrospinning-Reactive Coating Strategy

Skin regeneration attracts tremendous interest due to the important role of skin for human protection and beauty. Thus, methods allowing artificial skin to be carried out in a controllable fashion are potentially important for wound healing, which involves an intersection of materials, medicine, biology, and other disciplines. Herein, aiming at a new general methodology for fleshy materials, a new hydrogel-loaded hydrophobic-hydrophilic nanofiber fleshy artificial skin is designed and fabricated. The gradient hydrogel-loaded nanofiber artificial skin integrates both advantages of nanofiber and hydrogel, exhibiting fleshy feature (comparability to real skin in terms of appearance, texture, and function), excellent air permeability, compatibility, and good mechanical and antibacterial property. Interestingly, the efficient transport channels are formed throughout the hydrogel-loaded nanofiber structure, which is beneficial for water absorption and transfer. These advantages enable the establishment of a moist and favorable microenvironment; thus, greatly accelerating wound healing process. This work couples microfluidic electrospinning with reactive coating technique, which is in favor of material design and fabrication with controllable and uniform structures. The hydrogel-loaded nanofiber fleshy artificial skin shows comparability to real skin in terms of beauty, texture, and function, which would definitely provide new opportunities for the further optimization and upgrading of artificial skin.

Antibacterial polylysine-containing hydrogels for hemostatic and wound healing applications: preparation methods, current advances and future perspectives

The treatment of various types of wounds such as dermal wounds, multidrug resistant bacteria-infected wounds, and chronic diabetic wounds is one of the critical challenges facing healthcare systems. Delayed wound healing can impose a remarkable burden on patients and health care professionals. In this case, given their unique three-dimensional porous structure, biocompatibility, high hydrophilicity, capability to provide a moist environment while absorbing wound exudate, permeability to both gas and oxygen, and tunable mechanical properties, hydrogels with antibacterial function are one of the most promising candidates for wound healing applications. Polylysine is a cationic polymer with the advantages of inherent antibacterial properties, biodegradability, and biocompatibility. Therefore, its utilization to engineer antibacterial hydrogels for accelerating wound healing is of great interest. In this review, we initially discuss polylysine properties, and then focus on the most recent advances in polylysine-containing hydrogels (since 2016) prepared using various chemical and physical crosslinking methods for hemostasis and wound healing applications. Finally, the challenges and future directions in the engineering of these antibacterial hydrogels for wound healing are discussed.

Freeze-Dryable, Stable, and Click-Reactive Nanoparticles Composed of Cello-oligosaccharides for Biomolecular Sensing

Nanoparticles have been widely used as platforms for biomolecular sensing because of their high specific surface area and attractive properties depending on their constituents and structures. Nevertheless, it remains challenging to develop nanoparticulate sensing platforms that are easily storable without aggregation and conjugatable with various ligands in a simple manner. Herein, we demonstrate that nanoparticulate assemblies of cello-oligosaccharides with terminal azido groups are promising candidates. Azidated cello-oligosaccharides can be readily synthesized via the enzyme-catalyzed oligomerization reaction. This study characterized the assembled structures of azidated cello-oligosaccharides produced during the enzymatic synthesis and revealed that the terminal azidated cello-oligosaccharides formed rectangular nanosheet-shaped lamellar crystals. The azido groups located on the nanosheet surfaces were successfully exploited for antigen conjugation via the click chemistry. The resultant antigen-conjugated nanosheets allowed for the quantitative and specific detection of a corresponding antibody, even in 10% serum, owing to the antifouling properties of cello-oligosaccharide assemblies against proteins. It was found that the functionalized nanosheets were redispersible in water after freeze-drying. This remarkable characteristic is attributed to the well-hydrated saccharide residues on the nanosheet surfaces. Moreover, the antibody detection capability did not decline after the thermal treatment of the functionalized nanosheets in a freeze-dried state. Our findings contribute to developing convenient nanoparticulate biomolecular sensing platforms.

Highly elastic, fatigue-resistant, antibacterial, conductive, and nanocellulose-enhanced hydrogels with selenium nanoparticles loading as strain sensors

The fabrication of highly elastic, fatigue-resistant and conductive hydrogels with antibacterial properties is highly desirable in the field of wearable devices. However, it remains challenging to simultaneously realize the above properties within one hydrogel without compromising excellent sensing ability. Herein, we fabricated a highly elastic, fatigue-resistant, conductive, antibacterial and cellulose nanocrystal (CNC) enhanced hydrogel as a sensitive strain sensor by the synergistic effect of biosynthesized selenium nanoparticles (BioSeNPs), MXene and nanocellulose. The structure and potential mechanism to generate biologically synthesized SeNPs (BioSeNPs) were systematically investigated, and the role of protease A (PrA) in enhancing the adsorption between proteins and SeNPs was demonstrated. Additionally, owing to the incorporation of BioSeNPs, CNC and MXene, the synthesized hydrogels showed high elasticity, excellent fatigue resistance and antibacterial properties. More importantly, the sensitivity of hydrogels determined by the gauge factor was as high as 6.24 when a high strain was applied (400-700 %). This study provides a new horizon to synthesize high-performance antibacterial and conductive hydrogels for soft electronics applications.

The orchestration of sustained drug delivery by bacterial cellulose/gelatin nanocomposites reinforced with carboxylic carbon nanotubes

Recently, modifying bacterial cellulose (BC) by compositing it with other nano-biomaterials has become inevitable to achieve its desired properties in drug delivery. To address this, our study endeavors to utilize an in-situ fabrication method for the creation of a multifunctional BC/gelatin (BC/Gel) platform reinforced with carboxylic multi-walled carbon nanotubes (cMWCNTs) as a sustainable delivery model of biomolecules. Incipiently, cMWCNTs were loaded with human serum albumin (HSA) as a drug model, with an optimized nanoparticle-to-protein ratio of 1:5 and loading efficiency of 90.0 ± 1.0 % before incorporation into BC/Gel hydrogels. By comparison, nanocomposition improved the surface area and overall porosity of BC/Gel up to 58.0 ± 1.3 m2/g and 85.5 ± 1.1 %, respectively. Likewise, significant wettability of 44.0 ± 0.1° and dramatic biodegradation rate of 36.9 ± 1.2 % were other exceptionally gained attributes. Meanwhile, with a Zero-order kinetic mechanism, CNT-HSA integration facilitated the controlled release of 56.0 ± 0.9 % HSA over 7 days. Drug-loaded nanocomposites showcased >70 % viability during in vitro cellular trials using Human Foreskin Fibroblasts (HFF). Overall, BC/Gel/CNT-HSA nanocomposite exhibited favorable cell behavior, devoid of cytotoxic manifestations. Consequently, this BC-based nanocomposite scaffold implicates the premiere capability in the sustained delivery of an extended range of protein biomolecules, offering a promising therapeutic avenue for bolstering tissue regeneration.

Anti-Wound Dehiscence and Antibacterial Dressing with Highly Efficient Self-Healing Feature for Guided Bone Regeneration Wound Closure

Guided bone regeneration (GBR) is a well-established technique for preserving and enhancing alveolar ridge structures. Success in GBR relies on fulfilling the Primary wound closure, Angiogenesis, Space maintenance, and Stability (PASS) principles. Conventional methods, involving titanium meshes and sutures, have drawbacks, including the need for secondary removal and customization challenges. To address these issues, an innovative multifunctional GBR dressing (MGD) based on self-healing elastomer (PUIDS) is introduced. MGD provides sutureless wound closure, prevents food particle accumulation, and maintains a stable environment for bone growth. It offers biocompatibility, bactericidal properties, and effectiveness in an oral GBR model. In summary, MGD provides a reliable, stable osteogenic environment for GBR, aligning with PASS principles and promoting superior post-surgery bone regeneration.

A Photo-induced Cross-Linking Enhanced A and B Combined Multi-Functional Spray Hydrogel Instantly Protects and Promotes of Irregular Dynamic Wound Healing

Wounds in harsh environments can face long-term inflammation and persistent infection, which can slow healing. Wound spray is a product that can be rapidly applied to large and irregularly dynamic wounds, and can quickly form a protective film in situ to inhibit external environmental infection. In this study, a biodegradable A and B combined multi-functional spray hydrogel is developed with methacrylate-modified chitosan (CSMA1st) and ferulic acid (FA) as type A raw materials and oxidized Bletilla striata polysaccharide (OBSP) as type B raw materials. The precursor CSMA1st-FA/OBSP (CSOB-FA1st) hydrogel is formed by the self-cross-linking of dynamic Schiff base bonds, the CSMA-FA/OBSP (CSOB-FA) hydrogel is formed quickly after UV-vis light, so that the hydrogel fits with the wound. Rapid spraying and curing provide sufficient flexibility and rapidity for wounds and the hydrogel has good injectability, adhesive, and mechanical strength. In rats and miniature pigs, the A and B combined spray hydrogel can shrink wounds and promote healing of infected wounds, and promote the enrichment of fibrocyte populations. Therefore, the multifunctional spray hydrogel combined with A and B can protect irregular dynamic wounds, prevent wound infection and secondary injury, and be used for safe and effective wound treatment, which has a good prospect for development.

An antibacterial biologic patch based on bacterial cellulose for repair of infected hernias

Infection-associated complications and repair failures and antibiotic resistance have emerged as a formidable challenge in hernia repair surgery. Consequently, the development of antibiotic-free antibacterial patches for hernia repair has become an exigent clinical necessity. Herein, a GBC/Gel/LL37 biological patch (biopatch) with exceptional antibacterial properties is fabricated by grafting 2-Methacryloyloxyethyl trimethylammonium chloride (METAC), a unique quaternary ammonium salt with vinyl, onto bacterial cellulose (GBC), followed by compounding with gelatin (Gel) and LL37. The GBC/Gel/LL37 biopatch exhibits stable swelling capacity, remarkable mechanical properties, flexibility, and favorable biocompatibility. The synergistic effect of METAC and LL37 confers upon the GBC/Gel/LL37 biopatch excellent antibacterial efficacy against Staphylococcus aureus and Escherichia coli, effectively eliminating invading bacteria without the aid of exogenous antibiotics in vivo while significantly reducing local acute inflammation caused by infection. Furthermore, the practical efficacy of the GBC/Gel/LL37 biopatch is evaluated in an infected ventral hernia model, revealing that the GBC/Gel/LL37 biopatch can prevent the formation of visceral adhesions, facilitate the repair of infected ventral hernia, and effectively mitigate chronic inflammation. The prepared antibacterial GBC/Gel/LL37 biopatch is very effective in dealing with the risk of infection in hernia repair surgery and offers potential clinical opportunities for other soft injuries, exhibiting considerable clinical application prospects.

Stimuli‐Responsive Hydrogels for Antibacterial Applications

Hydrogels have emerged as promising candidates for biomedical applications, especially in the field of antibacterial therapeutics, due to their unique structural properties, highly tunable physicochemical properties, and excellent biocompatibility. The integration of stimuli-responsive functions into antibacterial hydrogels holds the potential to enhance their antibacterial properties and therapeutic efficacy, dynamically responding to different external or internal stimuli, such as pH, temperature, enzymes, and light. Therefore, this review describes the applications of hydrogel dressings responsive to different stimuli in antibacterial therapy. The collaborative interaction between stimuli-responsive hydrogels and antibacterial materials is discussed. This synergistic approach, in contrast to conventional antibacterial materials, not only amplifies the antibacterial effect but also alleviates adverse side effects and diminishes the incidence of multiple infections and drug resistance. The review provides a comprehensive overview of the current challenges and outlines future research directions for stimuli-responsive antibacterial hydrogels. It underscores the imperative for ongoing interdisciplinary research aimed at unraveling the mechanisms of wound healing. This understanding is crucial for optimizing the design and implementation of stimuli-responsive antibacterial hydrogels. Ultimately, this review aims to offer scientific guidance for the development and practical clinical application of stimuli-responsive antibacterial hydrogel dressings.

Biological scaffold as potential platforms for stem cells: Current development and applications in wound healing

Wound repair is a complex challenge for both clinical practitioners and researchers. Conventional approaches for wound repair have several limitations. Stem cell-based therapy has emerged as a novel strategy to address this issue, exhibiting significant potential for enhancing wound healing rates, improving wound quality, and promoting skin regeneration. However, the use of stem cells in skin regeneration presents several challenges. Recently, stem cells and biomaterials have been identified as crucial components of the wound-healing process. Combination therapy involving the development of biocompatible scaffolds, accompanying cells, multiple biological factors, and structures resembling the natural extracellular matrix (ECM) has gained considerable attention. Biological scaffolds encompass a range of biomaterials that serve as platforms for seeding stem cells, providing them with an environment conducive to growth, similar to that of the ECM. These scaffolds facilitate the delivery and application of stem cells for tissue regeneration and wound healing. This article provides a comprehensive review of the current developments and applications of biological scaffolds for stem cells in wound healing, emphasizing their capacity to facilitate stem cell adhesion, proliferation, differentiation, and paracrine functions. Additionally, we identify the pivotal characteristics of the scaffolds that contribute to enhanced cellular activity.

Nanocellulose-Based Hybrid Scaffolds for Skin and Bone Tissue Engineering: A 10-Year Overview

Cellulose, the most abundant polymer on Earth, has been widely utilized in its nanoform due to its excellent properties, finding applications across various scientific fields. As the demand for nanocellulose continues to rise and its ease of use becomes apparent, there has been a significant increase in research publications centered on this biomaterial. Nanocellulose, in its different forms, has shown tremendous promise as a tissue engineered scaffold for regeneration and repair. Particularly, nanocellulose-based composites and scaffolds have emerged as highly demanding materials for both soft and hard tissue engineering. Medical practitioners have traditionally relied on collagen and its analogue, gelatin, for treating tissue damage. However, the limited mechanical strength of these biopolymers restricts their direct use in various applications. This issue can be overcome by making hybrids of these biopolymers with nanocellulose. This review presents a comprehensive analysis of the recent and most relevant publications focusing on hybrid composites of collagen and gelatin with a specific emphasis on their combination with nanocellulose. While bone and skin tissue engineering represents two areas where a majority of researchers are concentrating their efforts, this review highlights the use of nanocellulose-based hybrids in these contexts.

KGRT peptide incorporated hydrogel with antibacterial activity for wound healing by optimizing cellular functions via ERK/eNOS signaling

Bacterial infected wounds, which is characterized by easy infection, multiple inflammation and slow healing, is a complex symptom, resulting from metabolic disorder of the wound microenvironment. In this study, a series of self-healing double-network hydrogels based on KGRT peptide (Lys-Gly-Arg-Thr) with antibacterial, anti-inflammatory and optimizing cellular functions were designed to promote the healing of infected wounds with full-thickness skin defects. Moreover, the dextran hydrogelintroduces a large number of side chains, which are entangled with each other in the Schiff base network to form an interpenetrating structure. The hydrogel might regulate cell metabolism, differentiation and vascular endothelial growth factor (VEGF) function. Importantly, both in vitro and in vivo data showed that hydrogel not only has good antibacterial properties (99.8 %), but also can eradicate bacterial biofilm, effectively reduce inflammation (down-regulated IL-1β, TNF-α and ROS) and accelerate chronic wound healing process by speeding-up wound closure, increasing granulation tissue thickness, collagen deposition, angiogenesis (up-regulated CD31). The hydrogel could up-regulate mRNA expression of PI3K, AKT, ERK, eNOS, HIF-1α and VEGF, which were correlated with wound healing. Consistently, the hydrogel could promote infected wounds healing and inhibit inflammation through ERK/eNOS signaling pathway. Collectively, hydrogel has excellent clinical application potential for promoting infected wound healing.

Influence of chitosan and hydroxyethyl cellulose modifications towards the design of cross-linked double networks hydrogel for diabetic wound healing

The wound dressings' lack of antioxidant and antibacterial properties, and delayed wound healing limit their use in wound treatment and management. Recent advances in dressing materials are aimed at improving the limitations discussed above. Therefore, the aim of this study includes the preparation and characterization of oxidized hydroxyethyl cellulose (OHEC) and ferulic acid-grafted chitosan (CS-FA) hydrogel loaded with green synthesized selenium nanoparticles (Se NPs) (OHEC-CS-FA-Se NPs named as nanohydrogel) for diabetic wound healing. The structure and properties of the hydrogel was characterized by FTIR, FE-SEM, HR-TEM, EDAX, UV-Vis spectrophotometry, XRD, DLS, zeta potential and rheological studies. The findings of these experiments demonstrate that nanohydrogel possesses a variety of outstanding qualities, including an optimal gel time, good swelling characteristics, a fair water retention rate, a good degradation rate, and strong mechanical stability. Nanohydrogel has been shown to have a synergistic impact by significantly increasing antioxidant activity by scavenging ABTS and DPPH radicals. The nanohydrogel's strong biocompatibility was confirmed by cytocompatibility testing using L929 mouse fibroblast cells. In addition, the wound healing potential of nanohydrogel was tested on L929 cells by an in vitro scratch assay and the nanohydrogel showed a wound closure rate of 100 % after 12 h. In addition to this study, nanohydrogel has demonstrated significant antimicrobial properties against human and wound infection causing pathogens such as Bacillus subtilis, methicillin-resistant Staphylococcus aureus (MRSA), Escherichia coli, and Pseudomonas aeruginosa. In the animal model, almost complete diabetic wound healing was achieved on day 14 after application of the nanohydrogel. The results obtained indicate that the multifunctional bioactive nature of OHEC-CS-FA-Se NPs showed exceptional antioxidant and antibacterial potential for the treatment of infected and chronic wounds.