Wound Dressings Research Articles

Construction of acidic microenvironment by Cu-TCPP nanozyme composited deprotonatable polymeric nanofibers for efficient antibacterial activity

The issue of bacterial resistance caused by conventional antibiotics has emerged as a major challenge in clinical treatment. Nanozymes, based on catalysis and devoid of bacterial resistance, provide a novel approach to eradicating bacteria. However, the practical potential of these nanozymes is limited by their low and readily pH-affected catalytic activity. Herein, the enzyme activity was optimized starting from the synthesis of nanozyme and the selection of carboxylate-containing polymers for the matrix. Specifically, various copper-tetrakis (4-carboxyphenyl) porphyrin (Cu-TCPP) were initially synthesized employing three copper sources, and among them, Cu-TCPP derived from Cu2O with higher catalytic activity was preferred. Subsequently, Cu-TCPP composite fibrous membranes were further obtained by electrospinning from their blend solutions with different polymers with distinct deprotonation capabilities. Thus, an acidic microenvironment conducive to the exertion of enzyme activity was constructed. The fabricated composite nanofibrous membrane could dissociate hydrogen ions to construct a localized acidic microenvironment even under weakly alkaline conditions, thereby enhancing the enzyme activity and improving the antibacterial effect. Further in vivo experiments demonstrated its favorable antibacterial ability and accelerated wound healing effect. The enhancement strategy of enzyme activity in this study brings inspiration for the design of nanozyme composited wound dressings and holds significant potential for clinical antibacterial applications

In vitro Analysis of XLAsp-P2 Peptide Loaded Cellulose Acetate Nanofiber for Wound Healing.

Recently, nanofiber-based wound dressings are currently a viable strategy to expedite the healing of wounds by providing a suitable microenvironment for tissue growth with active ingredients. This research study subjects the development of electrospun cellulose acetate (CA) nanofibers loaded with the XLAsp-P2, an antimicrobial peptide (AMP) that holds great potential for enhanced wound healing as a therapeutic agent. The synthesized XLAsp-P2-loaded CA nanofibers were fabricated via three loading percentages, 0.1 %, 0.2 %, and 0.3 % w/w, and characterized and evaluated their antimicrobial potential with MTT assay and Agar overlay methods as an alternative strategy. FT-IR analysis confirmed the compatibility of the peptide loaded CA nanocomposite, showing distinct peaks corresponding to the constituent materials. Scanning electron microscopy (SEM) analysis was employed to characterize the morphology of electrospun peptide CA nanocomposites and illustrate the fiber's size at the nanoscale. The in vitro release study during the 24 hrs, 87 % of the peptide was released which was approximately 5.2 mg; which was closer matched to the square root model of Higuchi at room temperature. MTT assay presented sensitive results towards Gram-positive bacteria compared to Gram Negative bacteria; which corresponded to the inhibition zones of the Agar overlay method proving that Escherichia coli (ATCC 25922) 17.66 ± 0.38 mm and Pseudomonas aeruginosa (ATCC 27853) 17.44 ± 0.38 mm exhibited moderate susceptibility, while Staphylococcus aureus (ATCC 25923)19.89 ± 0.69 mm and Bacillus cereus (ATCC 11778) 23.00 ± 0.33 mm showed promising responses. Collectively, The study's findings indicate that the XLAsp-P2 incorporated CA mat possesses an opportunity to function as an efficient platform for delivering therapeutic peptides.

One-step construction of silver nanoparticles immersed hydrogels by triple-helix β-glucans and the application in infectious wound healing

Hydrogels composed of polysaccharides and silver nanoparticles (AgNPs) are widely recognized for their application in wound dressings, particularly for healing wounds prone to infection. Traditional methods for preparing AgNP-immersed hydrogels are often complex, costly, and may lead to sustained cytotoxicity. To address these challenges, we developed a biocompatible, one-step green reduction strategy to generate AgNPs within hydrogels using a triple-helix β-glucan (PCPA) derived from Poria cocos, a renowned Chinese traditional herb. PCPA serves as a reducing agent, converting silver ions into AgNPs while its triple-helix conformation prevents AgNP aggregation. The resulting hydrogel (PAg-G) is injectable and contains uniformly distributed AgNPs. PAg-G exhibits broad-spectrum antimicrobial activity and enhanced bioactivity. The in vivo studies on S.aureus-infected SD rats demonstrated that PAg-G accelerates wound healing within 12 days by down-regulating inflammatory factors such as IL-6 and TNF-α, and up-regulating VEGF and CD31 expression, promoting neovascularization in wound tissues. This innovative one-step construction of AgNP-immersed hydrogels offers a promising approach for the development of antimicrobial hydrogels, especially for treating bacterial-infected wounds.

Effect of Bioplastic Material on Adhesion, Growth, and Proliferative Activity of Human Fibroblasts When Incubated in Solutions Mimic the Acidity of Wound an Acute and Chronic Inflammation.

: The aim of this study was to characterize the effect of bioplastic material based on collagen, hyaluronic acid, and elastin on the viability and proliferative activity of human fibroblasts in conditions simulating the acidity of acute and chronic wounds. : Bioplastic material was made according to the method described in RF patent no.2722744. Adhesive properties and proliferative activity of human fibroblasts were assessed visually using fluorescent microscopy. The number of apoptotic and necrotic cells was assessed by flow cytometry (BD FACSCanto II) using the commercial FITC Annexin V Apoptosis Detection Kit I (BD Pharmingen). The strength, Young's modulus, and elasticity of the gels were determined on a TA.XT-plus texture analyzer (Stable Micro Systems, Great Britain). : Using the methods of luminescent microscopy and flow cytometry, we found that the cell viability (namely, adhesive properties and proliferative activity) decreases after incubation on condition mimic of physiological acidosis. We found that bioplastic material contributes to the preservation of adhesive properties, viability, and proliferative activity of fibroblasts in physiological acidosis conditions. The results obtained indicate that bioplastic material based on soluble dermis components can be used as a biologically active component of wound dressings to increase the effectiveness of reparative regeneration, especially in cases of excessive acute inflammation.

Enhancement of antibacterial activity in electrospun fibrous membranes based on quaternized chitosan with caffeic acid and berberine chloride for wound dressing applications.

Electrospun nanofibers made from chitosan are promising materials for surgical wound dressings due to their non-toxicity and biocompatibility. However, the antibacterial activity of chitosan is limited by its poor water solubility under physiological conditions. This study addresses this issue by producing electrospun nanofibers mainly from natural compounds, including chitosan and quaternized chitosan, which enhance both its solubility for electrospinning and the antibacterial activity of the resulting electrospun nanofibers. Additionally, antimicrobial agents like caffeic acid or berberine chloride were incorporated. The glutaraldehyde-treated nanofibers showed improved mechanical properties, with an average tensile strength exceeding 2.7 MPa, comparable to other chitosan-based wound dressings. They also demonstrated enhanced water stability, retaining over 50% of their original weight after one week in phosphate-buffered saline (PBS) at 37 °C. The morphology and performance of these nanofibers were thoroughly examined and discussed. Furthermore, these membranes displayed rapid drug release, indicating potential for inhibiting bacterial growth. Antibacterial assays revealed that S2-CX nanofibers containing caffeic acid were most effective against E. coli and S. aureus, reducing their survival rates to nearly 0%. Similarly, berberine chloride-containing S4-BX nanofibers reduced the survival rates of E. coli and S. aureus to 19.82% and 0%, respectively. These findings suggest that electrospun membranes incorporating chitosan and caffeic acid hold significant potential for use in antibacterial wound dressings and drug delivery applications.

Material Technologies for Improved Diabetic Foot Ulcer (DFU) Treatment: A Questionnaire Study of Healthcare Professionals’ Needs

Background/Objectives: Diabetic foot ulcers (DFUs) are a common and severe complication of diabetic patients, with significant global prevalence and associated health burdens, including high recurrence rates, lower-limb amputations, and substantial associated economic costs. This study aimed to understand the user needs of healthcare professionals treating diabetic foot ulcers for newly developed material technologies. Methods: An open-ended questionnaire was used to identify user needs, identify the limitations of current treatments, and determine the specific requirements for ideal treatment. This information was used to develop a list of key considerations for creating innovative material technologies to improve diabetic wound treatment results. Results: Most respondents indicated that they followed published treatment guidelines for DFUs but noted that treatment often required a case-specific approach. Antibiotics and surgical debridement were commonly used for infection control. The participants showed a strong preference for wound dressings with lasting antibacterial properties. Respondents identified ideal properties for new products, including ease of use, enhanced antibacterial properties, affordability, and targeted biological activity. The respondents also highlighted the importance of a holistic approach to DFU management, integrating product development with comprehensive care strategies and patient education. Conclusions: This study highlights the complexity of DFU care, emphasizing that no single product can address all treatment needs. Future materials could focus on combination therapies and specific use cases. Additionally, understanding global variations in treatment practices and educating users on the proper application of newly developed material technologies is crucial for improving the management of DFUs and patient outcomes.

Physically Cross-Linked PVA Hydrogels as Potential Wound Dressings: How Freezing Conditions and Formulation Composition Define Cryogel Structure and Performance

Objectives: Hydrogels produced using the freeze–thaw method have demonstrated significant potential for wound management applications. However, their production requires precise control over critical factors including freezing temperature and the choice of matrix-forming excipients, for which no consensus on the optimal conditions currently exists. This study aimed to address this gap by evaluating the effects of the above-mentioned variables on cryogel performance. Methods: Mechanical properties, absorption capacity, and microstructure were assessed alongside advanced analyses using differential scanning calorimetry (DSC) and low-field nuclear magnetic resonance relaxometry (LF TD NMR). Results: The results demonstrated that fully hydrolyzed polyvinyl alcohol (PVA) with a molecular weight above 61,000 g/mol is essential for producing high-performance cryogels. Among the tested formulations, an 8% (w/w) PVA56–98 solution (Mw~195,000; DH = 98.0–98.8%) with 10% (w/w) propylene glycol (PG) provided the best balance of stretchability, durability, and low adhesion. Notably, while −25 °C is often used for cryogel preparation, freezing the gel precursor at −80 °C yielded superior results, producing materials with more open, interconnected structures and enhanced mechanical strength and elasticity—deviating from conventional practices. Conclusions: The designed cryogel prototypes exhibited functional properties comparable to or even surpassing commercial wound dressings, except for absorption capacity, which remained lower. Despite this, the cryogel prototypes demonstrated potential as wound dressings, particularly for use in dry or minimally exuding wounds. All in all, this study provides a comprehensive analysis of the physicochemical and functional properties of PVA cryogels, establishing a strong foundation for the development of advanced wound dressing systems.

Defining critical quality attributes and composition parameters for burn wound dressings: Antibiotic-anesthetic films as a model

The management of wounds primarily revolves around pain relief, effective infection control and the promotion of tissue regeneration to prevent complications like chronic skin wounds. While polymeric bioactive films are innovative alternatives to conventional wound dressings, there exists a dearth of guidance regarding their quality control. This underscores the imperative need to establish precise critical quality attributes, a task undertaken within this study using an antibiotic-anesthetic film as a model. The aim was to establish the influence of critical composition and process parameters and optimize the formula.First, the quality target product profile was defined, and critical quality attributes were identified. Our material selection included ciprofloxacin hydrochloride (an antimicrobial), lidocaine hydrochloride (an anesthetic), as well as excipients, such as sodium alginate, sodium hyaluronate, carbomer and glycerol. The critical components were identified through a risk assessment matrix, and their influence on film composition was determined by experimental verification using Design-Expert® software. A full factorial design was employed to assess the effects of sodium hyaluronate, carbomer and glycerol (as independent variables) on transparency, homogeneity, folding capacity and handling. Following this, an optimized formulation was achieved and subjected to further characterization.These optimized antibiotic-anesthetic films exhibited uniform micro-distribution of components, ensuring dosage uniformity. Both ciprofloxacin hydrochloride and lidocaine hydrochloride displayed sustained release profiles, suggesting potential therapeutic benefits for skin wounds. Furthermore, the resistance and elongation properties were similar to those of human skin.Utilizing a QbD approach, we successfully developed an optimized antibiotic-anesthetic film that adhered to the essential critical quality attributes. This films exhibits potential utility as a wound dressing. The findings presented in this study establish a fundamental framework for delineating the critical quality attributes of dressing films and refining their formulation to optimize wound treatment.

Guar gum and gelatin-based hydrogel wound dressing loaded calcium-containing nanoparticles: Simpler preparation, faster hemostasis and faster pro-wound healing properties

In this work, we prepared a novel calcium-containing nanoparticles (CaNPs) and added it to a hydrogel composed of guar gum (GG) and gelatin (Gel) as a backbone to prepare a novel hydrogel (GG@Gel-Ca) with rapid hemostasis, antibacterial effect and wound healing promotion. We conducted a series of test to characterize the structure and properties of CaNPs and GG@Gel-Ca hydrogel. The results showed that CaNPs had been successfully prepared and had regular morphology, and the GG@Gel-Ca hydrogel had good swelling ability, good antibacterial ability and excellent hemocompatibility/hemostasis and perfect cytocompatibility. Animal experiments also showed that GG@Gel-Ca hydrogel was able to achieve rapid hemostasis in the rat liver hemostasis model and it could also accelerate wound healing in S. aureus infections. In summary, we developed an innovative and practical method to prepare a gentle hydrogel, employing two natural polysaccharides that remained unmodified and untreated with chemicals. By incorporating the prepared calcium nanoparticles into this hydrogel, we successfully achieved effective hemostasis. Therefore, the GG@Gel-Ca hydrogel has the potential for application as hemostatic wound dressings with antibacterial properties and good wound healing.

Graphene-Based Wound Dressings for Wound Healing: Mechanism, Technical Analysis, and Application Status.

The development of novel wound dressings is critical in medical care. Graphene and its derivatives possess excellent biomedical properties, making them highly suitable for various applications in medical dressings. This review provides a comprehensive technical analysis and the current application status of graphene-based medical dressings. Initially, we discuss the chemical structure and the fabrication method of graphene and its derivatives. We then provide a detailed summary of the mechanisms by which graphene materials promote wound repair across the four stages of wound healing. Subsequently, we categorize the types of graphene-based wound dressings and analyze corresponding characteristics. Finally, we analyze the challenges encountered at present and propose solutions regarding future development trends. This paper aims to serve as a reference for further research in skin tissue engineering and the development of innovative graphene-based medical dressings.

Copper oxide/biopolymer nanocomposites: synthesis and applications, a comprehensive review

Copper oxide particles have a significant role in various fields due to their many properties like special shape, size, and high surface area. Due to their rarity and unique characteristics, such as their large surface area, paramagnetic nature, and ease of separation, Copper oxide nanoparticles have received the greatest attention. Chitosan, Guar Gum, Tamarind, Alginate, starch, cellulose, polysaccharide, etc. are examples of natural biopolymers that have proven to be excellent hosts for the creation of CuO nanoparticles. Long-established fabrication techniques for biopolymer-based CuO nanocomposites include co-precipitations, green synthesis, Solvent Casting Method, Alco thermal method, and Sol-Gel methods. Excellent biological characteristics of Copper oxide/biopolymer nanocomposites include their potent antibacterial activity against a variety of diseases as well as bacteria that are resistant to antibiotics. These characteristics have sparked the creation of numerous strategies with direct biological applications, including customized surfaces with antimicrobial effects, wound dressings, and modified textiles. This study aims to provide the very first biopolymer CuO nanoparticles to be reported in the previous ten years as well as its appealing methodology in diverse applications.

Synthesis and characterization of novel electrospun nanofibers based on taro starch: influence of solvent and isolation agent on morphology and diameter

AbstractThe utilization of natural polymers in producing electrospun nanofibers has received significant attention due to their biocompatibility, sustainability and diverse range of applications. This research focuses on synthesizing electrospun nanofibers derived from taro starch isolated from tubers. The investigation utilized SEM to examine the structure and size of the electrospun nanofibers. Formic acid and dimethyl sulfoxide solvents were tested to determine the most efficient solvent system for synthesizing taro starch nanofibers. The results demonstrated that the taro starch nanofibers can be effectively synthesized when using formic acid as the primary solvent. The study also investigated the impact of altering the volumetric ratio of formic acid to water on nanofiber morphology and size, finding that a lower formic acid fraction produced smooth fibers while a higher fraction resulted in fused fibers. The electrospinnability was further evaluated by comparing the effects of different isolation agents—distilled water and sodium metabisulfite—during the isolation process. The isolation agent significantly affected the fiber diameter, with notable differences observed in the smoothness of taro starch nanofibers at starch solution concentrations of 13, 15 and 17 wt%. Overall, the results of the study showed that the formation of taro starch fibers was influenced by the type of solvent, the volume fraction of the solvent to water, and the starch isolation agent. Successful fabrication of nanofibers from taro starch and its optimization parameters can contribute to the development of environmentally friendly nanofiber materials and offer a variety of applications in biomedicine, food and environmental engineering, such as tissue engineering, wound dressing, drug delivery, functional food delivery and food packaging. © 2024 Society of Chemical Industry.

Alginate-chitosan hydrogel formulations for VEGFA expressed baculovirus delivery promoting angiogenesis for wound healing and revascularization

Abstract Background Baculoviruses, engineered to express growth factors, offer a promising avenue for short-term gene therapy, such as wound dressings, due to their safety and specificity. Encapsulation in natural polymers like alginate and chitosan addresses limitations like serum inactivation and fragility, while promoting sustained delivery and shielding from immune inactivation. Wound healing involves complex processes that can be enhanced by maintaining an antimicrobial, moist environment, which promotes cell migration and angiogenesis. Vascular endothelial cell growth factor A (VEGFA) is known to be one of the most potent pro-angiogenic factors and plays a key role in wound healing. Purpose This investigation seeks to enhance wound healing and angiogenesis, support the revascularization process, and provide anti-inflammatory and anti-microbial effects. Additionally, it aims to assess the preclinical efficacy and safety of the approach. Methods Ionic cross-linking was used for virus encapsulation under aseptic conditions. The capsules were assessed for their surface morphology, particle size, zeta potential, and in vitro release profile. Additionally, their therapeutic potential was studied using cell lines. The efficacy of hydrogel delivery of VEGFA-expressing baculoviruses in promoting cell migration and angiogenesis for wound healing applications was investigated on Human Umbilical Vein Endothelial Cells (HUVECs). Hydrogel morphology, swelling, and encapsulation efficiency were evaluated, along with endothelial tube formation assays and hemocompatibility studies on HUVECs. Results Encapsulation of baculovirus expressing the VEGFA gene in alginate and chitosan–alginate hydrogels achieve a high encapsulation efficiency of 99.9%. This allows for prolonged virus delivery and an increased therapeutic window. The encapsulated baculovirus maintains activity and is released over eight days, with a transduction efficiency of over 40%. This promotes tube formation, cell proliferation, and cell migration for angiogenesis, particularly beneficial for chronic wound-healing applications. The hydrogels also prevented E. coli and C. albicans growth directly below and inhibited C. albicans growth surrounding the alginate–chitosan hydrogels. The hydrogels demonstrated no cytotoxicity and good blood compatibility. Conclusion This proof of concept underscores the potential of encapsulated baculovirus delivery systems for various gene therapy applications including cardiovascular tissue regeneration and revascularization.

Commentary Innovations in Tissue Regeneration and Wound Healing: A Comparative Study of Nigeria and South Africa

Tissue regeneration and wound healing represent critical areas in medical science, with significant advance-ments in recent years. These fields involve restoring damaged tissues and promoting recovery, which are essential for improv-ing patient outcomes and quality of life. Innovations such as biomaterials, stem cell therapy, advanced wound dressings, and regenerative medicine have significantly impacted these areas. This study provides a comparative analysis of innovations in tissue regeneration and wound healing in Nigeria and South Africa. The focus includes technological advancements, research contributions, and statistical data to highlight progress and challenges in both countries. Data from various healthcare institu-tions, research publications, and government reports form the basis of this analysis.Additionally, surgical innovations that minimize wound occurrence and improve wound healing, such as mini-mally invasive surgery, negative pressure wound therapy (NPWT), and the use of advanced suture materials, are transforming clinical outcomes in both Nigeria and South Africa. Minimally invasive techniques reduce tissue damage, leading to smaller wounds and faster recovery. NPWT has proven effective in managing chronic wounds and reducing infection rates, while an-timicrobial and absorbable sutures have lowered complications related to wound closure. Cold plasma therapy and stem cell applications are also emerging as promising approaches for chronic wound care and tissue regeneration. These innovations, coupled with the efforts in regenerative medicine and biomaterials, are providing both nations with effective tools to manage wound healing more efficiently. This comparative study aims to shed light on the current state of tissue regeneration and wound healing in these nations, offering insights into the advancements made, the effectiveness of various approaches, and the potential future devel-opments in this vital medical field.

Hydrogen‐Bonded Organic Frameworks as a Carrier for Nanodrugs with Host–Guest Interaction for Smart Wound Dressing Applications

AbstractThis study introduces surface modification to conventional dressings utilizing adducts of a hydrogen‐bonded organic framework (HOF) with curcumin, curcumin–silver, curcumin‐zinc oxide nanoparticles, and citric acid drugs. Accordingly, eight HOF‐AMs and dressings modified with them were studied. The synthesized structures underwent characterization using various methods, including IR, 1H NMR, XRD, FE‐SEM, and EDX. FE‐SEM results show that the hexagonal morphology is maintained along with the crystal growth in the form of hexagonal tubes. In order to confirm the nanoscale nature of the structures, TEM analysis was conducted specifically for curcumin‐Ag nanoparticles and curcumin–ZnO nanoparticles which confirms the particle size smaller than 50 nm. Knowing the sensitivity of the release of the incorporated substances to temperature and pH, the controlled release of the drugs at two different temperatures (37 °C and 40 °C) and pH levels of 5.5, 7.4, and 9 at the modified dressings was investigated. Investigating the release of HOF‐AMs particles and modified dressings indicates that these products in both cases provide the possibility of drug release in alkaline and acidic pHs. Also, the results showed that increasing the temperature increases the release of curcumin particles in all its types. The modified dressings showed a loading capacity of more than 50 mg g−1.

Emerging Technological Advancement for Chronic Wound Treatment and Their Role in Accelerating Wound Healing.

Chronic wounds are a major healthcare burden and may severely affect the social, mental, and economic status of the patients. Any impairment in wound healing stages due to underlying factors leads to a prolonged healing time and subsequently to chronic wounds. Traditional approaches for the treatment of chronic wounds include dressing free local therapy, dressing therapy, and tissue engineering based scaffold therapies. However, traditional therapies need improvisation and have been advanced through breakthrough technologies. The present review spans traditional therapies and further gives an extensive account of advancements in the treatment of chronic wounds. Cutting edge technologies, such as 3D printing, which includes inkjet printing, fused deposition modeling, digital light processing, extrusion-based printing, microneedle array-based therapies, gene therapy, which includes microRNAs (miRNAs) therapy, and smart wound dressings for real time monitoring of wound conditions through assessment of pH, temperature, oxygen, moisture, metabolites, and their use for planning of better treatment strategies have been discussed in detail. The review further gives the future direction of treatments that will aid in lowering the healthcare burden caused due to chronic wounds.

Inclusion of Reduced Graphene Oxide to Silk Fibroin Hydrogels Improve the Conductive, Swelling and Wound Healing Capacity

AbstractDeveloping dressing for wound dressings represents a significant challenge for the scientific community. In this study, a conductive hydrogel was synthesized to promote the wound‐healing process. This hydrogel is composed of silk fibroin (SF), reduced graphene oxide (rGO), and glycerol (G). The impact of modifying the SF:rGO ratio, and the G content (%), on the physicochemical and biological properties. The hydrogels were characterized using FT‐IR, SEM, XRD, TGA, swelling, mechanical resistance, and conductivity. The cytotoxicity of the materials and their wound‐healing capacity in human fibroblasts were also determined. Chemical analysis revealed that the gelation of SF occurs due to the formation of β sheet structures, which was confirmed by the shift from amide I to amide II. An Increase in the SF:rGO ratio favored swelling behavior, although increasing G reduced this effect. The swelling of the hydrogel followed a Fick diffusion mechanism. Furthermore, the increase in the SF:rGO ratio and the percentage G improved the conductivity of the materials. The hydrogels were found to be non‐cytotoxic to human fibroblasts, and those containing rGO exhibited superior wound healing capacity compared to the positive control cell culture medium. Therefore, SF:rGO hydrogels could be considered promising candidates for wound dressing.

Evaluation effect of alginate hydrogel containing losartan on wound healing and gene expression.

Skin tissue engineering has become an increasingly popular alternative to conventional treatments for skin injuries. Hydrogels, owing to their advantages have become the ideal option for wound dressing, and they are extensively employed in a mixture of different drugs to accelerate wound healing. Sodium alginate is a readily available natural polymer with advantages such as bio-compatibility and a non-toxicological nature that is commonly used in hydrogel form for medical applications such as wound repair and drug delivery in skin regenerative medicine. Losartan is a medicine called angiotensin receptor blocker (ARB) that can prevent fibrosis by inhibiting AT1R (angiotensin II type 1 receptor). In this research, for the first time, three-dimensional scaffolds based on cross-linked alginate hydrogel with CaCl2 containing different concentrations of losartan for slow drug release and exudate absorption were prepared and characterized as wound dressing. Alginate hydrogel was mixed with 10, 1, 0.1, and 0.01mg/mL of losartan, and their properties such as morphology, chemical structure, water uptake properties, biodegradability, stability assay, rheology, blood compatibility, and cellular response were evaluated. In addition, the therapeutic efficiency of the developed hydrogels was then assessed in an in vitro wound healing model and with a gene expression. The results revealed that the hydrogel produced was very porous (porosity of 47.37 ± 3.76µm) with interconnected pores and biodegradable (weight loss percentage of 60.93 ± 4.51% over 14days). All hydrogel formulations have stability under various conditions. The use of CaCl2 as a cross-linker led to an increase in the viscosity of alginate hydrogels. An in vitro cell growth study revealed that no cytotoxicity was observed at the suggested dosage of the hydrogel. Increases in Losartan dosage, however, caused hemolysis. In vivo study in adult male rats with a full-thickness model showed greater than 80% improvement of the primary wound region after 2weeks of treatment with alginate hydrogel containing 0.1mg/mL Losartan. RT-PCR and immunohistochemistry analysis showed a decrease in expression level of TGF-β1 and VEGF in treatment groups. Histological analysis demonstrated that the alginate hydrogel containing Losartan can be effective in wound repair by decreasing the size of the scar and tissue remodeling, as evidenced by future in vivo studies.

Zwitterionic Polymers for Biomedical Applications: Antimicrobial and Antifouling Strategies toward Implantable Medical Devices and Drug Delivery.

Poly(ethylene glycol) (PEG) is extensively utilized in biomedical applications due to its biocompatibility; however, its thermal instability and susceptibility to oxidative degradation significantly constrain its long-term effectiveness. Zwitterionic polymers, characterized by their distinctive structure, enhanced stability, and superior biocompatibility, offer a more advantageous alternative. These polymers exhibit super hydrophilicity, resist nonspecific protein adsorption, and maintain stability in biological environments due to their charge-neutral ionic nature. Zwitterionic polymers enhance anticancer drug delivery by precisely targeting tumor cells and facilitating an efficient drug release. Their inherent antifouling properties and prolonged circulation within the bloodstream render them highly suitable for redox-sensitive drug carriers, thereby augmenting the antitumor efficacy. Moreover, zwitterionic polymers markedly mitigate biofouling in implants, biosensors, and wound dressings, thereby improving both their functionality and their therapeutic outcomes. These advantages arise from the formation of robust hydration layers, which significantly enhance the hemocompatibility and inhibit the adhesion of proteins, platelets, and bacteria. Zwitterionic polymers, including sulfobetaine (SB), phosphorylcholine (PC), and carboxybetaine (CB), are increasingly employed in blood-contacting devices and as effective coating materials for implantable devices. This mini-review paper aims to explore the recent diverse biomedical applications of zwitterionic polymers and highlight their advantageous properties compared with unmodified polymers. We will cover their use in drug delivery systems, tumor targeting nanocarriers, antibiofouling and antibacterial activities in implantable devices, tissue engineering, and diagnostic devices, demonstrating how their unique properties can translate into different applications. Through this exploration, this Perspective will display the potential of zwitterionic polymers as innovative polymer materials in the field of biomedical engineering and beyond.

Synthesis and Characterization of Carboxymethyl Chitosan/Polyvinyl Alcohol Containing Zinc Oxide Nanoparticles as Hydrogel Wound Dressing

Synthesis and Characterization of Carboxymethyl Chitosan/Polyvinyl Alcohol Containing Zinc Oxide Nanoparticles as Hydrogel Wound Dressing