Chitosan/PVA hydrogels incorporated with green synthesized cerium oxide nanoparticles for wound healing applications

Synthesis of bimetallic oxides (SrO-CoO) nanoparticles decorated polyacrylamide hydrogels for controlled drug release and wound healing applications

Hydrogels are polymeric structures characterized by their three-dimensional nature, insolubility in aqueous media, and remarkable ability to absorb significant amounts of water. Owing to their exceptional biocompatibility with living tissues, hydrogels find extensive use in various biomedical applications. Guggul gum grafted polyacrylamide hydrogels (SG) were prepared and green synthesized SrO, CoO and SrO-CoO nanoparticles (NPs) were incorporated with hydrogels (SrG, CoG, Sr-CoG) respectively. The fabricated hydrogels were characterized by various analytical techniques such as FTIR, XRD and SEM. XRD results confirmed the presence of Sr and Co metal nanoparticles in the fabricated hydrogels matrix, SrG pattern showed diffraction peaks at 2θ = 30°, 36.59°, 44.11°, 50.22° and 62.20° while CoG peaks appeared at 2θ = 36.59°, 42.32°, 61.18°, 74.05° and 77.08°. SG, SrG, CoG and Sr-CoG hydrogels showed 11%, 32%, 23% and 45% radical scavenging activity respectively as compared to standard BHT (Butylated hydroxyl toluene). In vitro drug release tests results showed that SG, SrG, CoG and Sr-CoG exhibited 21%, 16%, 13% and 10% sustained release of naproxen respectively. The results revealed that SrO and CoO nanoparticles dopped hydrogels possessed good wound healing potential as compared to conventional hydrogels, which provides great potential in clinical treatment for wounds.

Biogenesis of bacterial cellulose/xanthan/CeO2NPs composite films for active food packaging

The increasing significance of biopolymer-based food packaging can be attributed to its biodegradability and independence from petroleum-derived materials. Concurrently, metal oxide nanoparticles (NPs) have gained prominence as effective antimicrobial agents against both wild-type and antibiotic-resistant microbes. In this study, cerium oxide or ceria, CeO2, nanoparticles with an average diameter of 50 nm were synthesized via a green method utilizing Vibrio sp. VLC cell lysate supernatant. The synthesized CeO2 NPs displayed remarkable antimicrobial properties, inhibiting the growth of Escherichia coli and Staphylococcus aureus by 93.7 % and 98 %, respectively. To enhance the potential of bacterial cellulose (BC) for advanced applications, we developed a BC/xanthan/CeO2 nanocomposite using both ex situ and in situ techniques. The integration of CeO2 NPs within the nanocomposite structure not only improved the inherent properties of BC, but also rendered it suitable for use in active food packaging systems. The nanocomposite exhibited no significant cytotoxicity on the human dermal fibroblast (HDF) cells, confirming its safety. Nanocomposites containing biogenically synthesized CeO2 NPs demonstrated exceptional efficacy for reducing microbial contamination. Bread samples coated with nanocomposite films displayed no signs of microbial growth. These results support the application of BC/xanthan/CeO2 nanocomposites as suitable and effective coating materials for antimicrobial food packaging applications.

Advances in sustainable food packaging applications of chitosan/polyvinyl alcohol blend films

Researchers are addressing environmental concerns related to petroleum-based plastic packaging by exploring biopolymers from natural sources, chemical synthesis, and microbial fermentation. Despite the potential of individual biopolymers, they often exhibit limitations like low water resistance and poor mechanical properties. Blending polymers emerges as a promising strategy to overcome these challenges, creating films with enhanced performance. This review focuses on recent advancements in chitosan/polyvinyl alcohol (PVA) blend food packaging films. It covers molecular structure, properties, strategies for performance improvement, and applications in food preservation. The blend's excellent compatibility and intermolecular interactions make it a promising candidate for biodegradable films. Future research should explore large-scale thermoplastic technologies and investigate the incorporation of additives like natural extracts and nanoparticles to enhance film properties. Chitosan/PVA blend films offer a sustainable alternative to petroleum-based plastic packaging, with potential applications in practical food preservation.

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

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

Electrospun nanofibers synthesized from polymers incorporated with bioactive compounds for wound healing

The development of innovative wound dressing materials is crucial for effective wound care. It's an active area of research driven by a better understanding of chronic wound pathogenesis. Addressing wound care properly is a clinical challenge, but there is a growing demand for advancements in this field. The synergy of medicinal plants and nanotechnology offers a promising approach to expedite the healing process for both acute and chronic wounds by facilitating the appropriate progression through various healing phases. Metal nanoparticles play an increasingly pivotal role in promoting efficient wound healing and preventing secondary bacterial infections. Their small size and high surface area facilitate enhanced biological interaction and penetration at the wound site. Specifically designed for topical drug delivery, these nanoparticles enable the sustained release of therapeutic molecules, such as growth factors and antibiotics. This targeted approach ensures optimal cell-to-cell interactions, proliferation, and vascularization, fostering effective and controlled wound healing. Nanoscale scaffolds have significant attention due to their attractive properties, including delivery capacity, high porosity and high surface area. They mimic the Extracellular matrix (ECM) and hence biocompatible. In response to the alarming rise of antibiotic-resistant, biohybrid nanofibrous wound dressings are gradually replacing conventional antibiotic delivery systems. This emerging class of wound dressings comprises biopolymeric nanofibers with inherent antibacterial properties, nature-derived compounds, and biofunctional agents. Nanotechnology, diminutive nanomaterials, nanoscaffolds, nanofibers, and biomaterials are harnessed for targeted drug delivery aimed at wound healing. This review article discusses the effects of nanofibrous scaffolds loaded with nanoparticles on wound healing, including biological (in vivo and in vitro) and mechanical outcomes.

Classification and application of metal-based nanoantioxidants in medicine and healthcare

Antioxidants play an important role in the prevention of oxidative stress and have been widely used in medicine and healthcare. However, natural antioxidants have several limitations such as low stability, difficult long-term storage, and high cost of large-scale production. Along with significant advances in nanotechnology, nanomaterials have emerged as a promising solution to improve the limitations of natural antioxidants because of their high stability, easy storage, time effectiveness, and low cost. Among various types of nanomaterials exhibiting antioxidant activity, metal-based nanoantioxidants show excellent reactivity because of the presence of an unpaired electron in their atomic structure. In this review, we summarize some novel metal-based nanoantioxidants and classify them into two main categories, namely chain-breaking and preventive antioxidant nanomaterials. In addition, the applications of antioxidant nanomaterials in medicine and healthcare are also discussed. This review provides a deeper understanding of the mechanisms of metal-based nanoantioxidants and a guideline for using these nanomaterials in medicine and healthcare.

Metal-based nanoparticles: an alternative treatment for biofilm infection in hard-to-heal wounds

Metal-based nanoparticles (MNPs) are promoted as effective compounds in the treatment of bacterial infections and as possible alternatives to antibiotics. These MNPs are known to affect a broad spectrum of microorganisms using a multitude of strategies, including the induction of reactive oxygen species and interaction with the inner structures of the bacterial cells. The aim of this review was to summarise the latest studies about the effect of metal-based nanoparticles on pathogenic bacterial biofilm formed in wounds, using the examples of Gram-positive bacterium Staphylococcus aureus and Gram-negative bacterium Pseudomonas aeruginosa, as well as provide an overview of possible clinical applications.

Sustainable whey proteins-nanostructured zinc oxide-based films for the treatment of chronic wounds: New insights from biopharmaceutical studies

Chronic wounds represent silent epidemic affecting a large portion of the world population, especially the elders; in this context, the development of advanced bioactive dressings is imperative to accelerate wound healing process, while contrasting or preventing infections. The aim of the present work was to provide a deep characterization of the functional and biopharmaceutical properties of a sustainable thin and flexible films, composed of whey proteins alone (WPI) and added with nanostructured zinc oxide (WPZ) and intended for the management of chronic wounds. The potential of whey proteins-based films as wound dressings has been confirmed by their wettability, hydration properties, elastic behavior upon hydration, biodegradation propensity and, when added with nanostructured zinc oxide, antibacterial efficacy against both Gram-positive and Gram-negative pathogens, i.e. Staphylococcus aureus and Escherichia coli. In-vitro experiments, performed on normal human dermal fibroblasts, confirmed film cytocompatibility, also revealing the possible role of Zn2+ ions in promoting fibroblast proliferation. Finally, in-vivo studies on rat model confirmed film suitability to act as wound dressing, since able to ensure a regular healing process while providing effective protection from infections. In particular, both films WPI and WPZ are responsible for the formation in the wound bed of a continuous collagen layer similar to that of healthy skin.

Improving the optical, thermal, mechanical, electrical properties and antibacterial activity of PVA-chitosan by biosynthesized Ag nanoparticles: Eco-friendly nanocomposites for food packaging applications

In this study, nanocomposite films were produced by blending polyvinyl alcohol (PVA) and chitosan (Cs) polymers with 70 % PVA and 30 % Cs, incorporating silver nanoparticles (Ag NPs) via a solution-casting method. The research aims to investigate the impact of the biosynthesized Ag NPs by Chenopodium murale leaf extract on optical, morphological, mechanical, thermal, electrical, and antibacterial properties. XRD analysis showed a decrease in crystallinity degree with Ag NPs addition. TEM revealed Ag NPs in cubic and spherical shapes with an average size of 23.4 nm. SEM and AFM indicated surface morphology changes. FT-IR spectra showed interaction between Ag ions and the blend. The energy gap decreased with increasing Ag NPs concentration. TGA exhibited enhanced thermal stability. Mechanical properties improved significantly. AC electrical conductivity and dielectric parameters were studied. Antibacterial activity against Gram-positive and Gram-negative bacteria was observed. Overall, PVA/Cs-Ag NPs films show promise for food packaging and optoelectronic applications.

Diabetic wound healing function of PCL/cellulose acetate nanofiber engineered with chitosan/cerium oxide nanoparticles

The use of cerium oxide nanoparticles (CeO2NPs) in diabetic wound repair substances has shown promising results. Therefore, the study was conducted to introduce a novel nano-based wound dressing containing chitosan nanoparticles encapsulated with green synthesized cerium oxide nanoparticles using Thymus vulgaris extract (CeO2-CSNPs). The physical properties and structure of the nanoparticles were analyzed using XRD, DLS, FESEM and FTIR techniques. The electrospun PCL/cellulose acetate-based nanofiber was prepared and CeO2-CSNPs were integrated on the PCL/CA membrane by electrospraying. The physicochemical properties, morphology and biological characteristics of the electrospun nanocomposite were evaluated. The results showed that the nanocomposite with 0.1 % CeO2-CSNPs exhibited high antibacterial performance against S. aureus (<58.59 µg/mL). The PCL/CA/CeO2-CSNPs nanofiber showed significant antioxidant activity up to 89.59 %, cell viability improvement, and cell migration promotion up to 90.3 % after 48 h. The in vivo diabetic wound healing experiment revealed that PCL/CA/CeO2-CSNPs nanofibers can significantly increase the repair rate of diabetic wounds by up to 95.47 % after 15 days. The results of this research suggest that PCL/CA nanofiber mats functionalized with CeO2-CSNPs have the potential to be highly effective in treating diabetes-related wounds.

Hydrogels in Cutaneous Wound Healing: Insights into Characterization, Properties, Formulation and Therapeutic Potential

Hydrogels are polymeric materials that possess a set of characteristics meeting various requirements of an ideal wound dressing, making them promising for wound care. These features include, among others, the ability to absorb and retain large amounts of water and the capacity to closely mimic native structures, such as the extracellular matrix, facilitating various cellular processes like proliferation and differentiation. The polymers used in hydrogel formulations exhibit a broad spectrum of properties, allowing them to be classified into two main categories: natural polymers like collagen and chitosan, and synthetic polymers such as polyurethane and polyethylene glycol. This review offers a comprehensive overview and critical analysis of the key polymers that can constitute hydrogels, beginning with a brief contextualization of the polymers. It delves into their function, origin, and chemical structure, highlighting key sources of extraction and obtaining. Additionally, this review encompasses the main intrinsic properties of these polymers and their roles in the wound healing process, accompanied, whenever available, by explanations of the underlying mechanisms of action. It also addresses limitations and describes some studies on the effectiveness of isolated polymers in promoting skin regeneration and wound healing. Subsequently, we briefly discuss some application strategies of hydrogels derived from their intrinsic potential to promote the wound healing process. This can be achieved due to their role in the stimulation of angiogenesis, for example, or through the incorporation of substances like growth factors or drugs, such as antimicrobials, imparting new properties to the hydrogels. In addition to substance incorporation, the potential of hydrogels is also related to their ability to serve as a three-dimensional matrix for cell culture, whether it involves loading cells into the hydrogel or recruiting cells to the wound site, where they proliferate on the scaffold to form new tissue. The latter strategy presupposes the incorporation of biosensors into the hydrogel for real-time monitoring of wound conditions, such as temperature and pH. Future prospects are then ultimately addressed. As far as we are aware, this manuscript represents the first comprehensive approach that brings together and critically analyzes fundamental aspects of both natural and synthetic polymers constituting hydrogels in the context of cutaneous wound healing. It will serve as a foundational point for future studies, aiming to contribute to the development of an effective and environmentally friendly dressing for wounds.

Facile process ofHibiscusmucilage polymer formulation usingHibiscus rosa-sinensisleaves to treat second-degree burn and excision wounds

Mucilage is a sticky substance found in various plants and microorganisms and is made up of proteins and polysaccharides. Mucilage fromHibiscus rosa sinensisisis a complex polysaccharide traditionally used to treat different skin diseases. In our study, we fabricated mucilage polymer fromHibiscus rosa sinensisleaves and evaluated its potential application in second-degree burns and excision wounds. The physical properties of Hibiscus mucilage (HM) polymer were demonstrated by using Ultraviolet-visible absorption spectroscopy, x-ray diffraction, Fourier transform infrared spectroscopy, dynamic light scattering, Scanning electron microscopy, Brunauer-Emmett-Tellerand, Swelling ratio. The human cell lines WI-38, and HaCaT have been used forin-vitroexperiments like MTT, scratch wound, BrdU, ROS scavenging assays, and western blot analysis. The results of the MTT, scratch-wound, and BrdU assay indicated that the HM polymer is nontoxic in nature and also enhances both the properties of cellular migration and proliferation, respectively. On the other hand, the result of the ROS scavenging assay suggested that HM polymer enhances the antioxidant activity of cells while the western blot analysis designated that the HM polymer treatment caused downregulation of the pro-inflammatory cytokine IFN-γand upregulation of the pAkt (Serine 473) protein, and TGF-β1 signaling pathway. Therefore, allin-vitroexperimental studies recommended that HM polymer is biocompatible and has antioxidant and anti-inflammatory effects. In thein vivoexperiment, second-degree burns and excision wounds were created on the dorsal surface of male BALB/c mice. After the sixth day of HM polymer treatment have developed new tissue, hair follicles, blood vessels,α-SMA, and Collagen type-1 fiber on the burn and excision wound area while the 11th day of HM polymer treatment cured the wound area significantly. Therefore, it could be contemplated that HM polymer is a potential agent for treating different wounds in the near future.

CeO2 Nanoparticles to Promote Wound Healing: A Systematic Review

Cerium (Ce) is a hot topic in the field of materials research due to its electronic layer structure and the unique antioxidant abilities of its oxide (CeO2 ). Cerium oxide nanoparticles (CeO2 NPs) demonstrate their potential as an antioxidant and antibacterial agent. Current research focuses on whether they can be used to promote wound healing and in what manner. This article provides a systematic review of the various forms of CeO2 NPs that are used in wound-healing materials over the past decade, as well as the effectiveness demonstrated by in vivo and in vitro experiments, with a focus on the relationship between concentration and effectiveness. CeO2 NPs are expected to become effective ingredients in dressings that require antibacterial, antioxidant, and wound healing promoting properties. This article serves as a reference for further research and clinical applications of nano-sized CeO2 in wound healing.

Construction methods and biomedical applications of PVA-based hydrogels

Polyvinyl alcohol (PVA) hydrogel is favored by researchers due to its good biocompatibility, high mechanical strength, low friction coefficient, and suitable water content. The widely distributed hydroxyl side chains on the PVA molecule allow the hydrogels to be branched with various functional groups. By improving the synthesis method and changing the hydrogel structure, PVA-based hydrogels can obtain excellent cytocompatibility, flexibility, electrical conductivity, viscoelasticity, and antimicrobial properties, representing a good candidate for articular cartilage restoration, electronic skin, wound dressing, and other fields. This review introduces various preparation methods of PVA-based hydrogels and their wide applications in the biomedical field.

The Recent Progress of the Cellulose-Based Antibacterial Hydrogel

Cellulose-based antibacterial hydrogel has good biocompatibility, antibacterial performance, biodegradability, and other characteristics. It can be very compatible with human tissues and degradation, while its good water absorption and moisturizing properties can effectively absorb wound exudates, keep the wound moist, and promote wound healing. In this paper, the structural properties, and physical and chemical cross-linking preparation methods of cellulose-based antibacterial hydrogels were discussed in detail, and the application of cellulose-based hydrogels in the antibacterial field was deeply studied. In general, cellulose-based antibacterial hydrogels, as a new type of biomaterial, have shown good potential in antimicrobial properties and have been widely used. However, there are still some challenges, such as optimizing the preparation process and performance parameters, improving the antibacterial and physical properties, broadening the application range, and evaluating safety. However, with the deepening of research and technological progress, it is believed that cellulose-based antibacterial hydrogels will be applied and developed in more fields in the future.

Marine-derived polysaccharides and their therapeutic potential in wound healing application - A review

Polysaccharides originating from marine sources have been studied as potential material for use in wound dressings because of their desirable characteristics of biocompatibility, biodegradability, and low toxicity. Marine-derived polysaccharides used as wound dressing, provide several benefits such as promoting wound healing by providing a moist environment that facilitates cell migration and proliferation. They can also act as a barrier against external contaminants and provide a protective layer to prevent further damage to the wound. Research studies have shown that marine-derived polysaccharides can be used to develop different types of wound dressings such as hydrogels, films, and fibres. These dressings can be personalised to meet specific requirements based on the type and severity of the wound. For instance, hydrogels can be used for deep wounds to provide a moist environment, while films can be used for superficial wounds to provide a protective barrier. Additionally, these polysaccharides can be modified to improve their properties, such as enhancing their mechanical strength or increasing their ability to release bioactive molecules that can promote wound healing. Overall, marine-derived polysaccharides show great promise for developing effective and safe wound dressings for various wound types.

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

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

Cerium oxide nanoparticles: Synthesis methods and applications in wound healing

Wound care and treatment can be critical from a clinical standpoint. While different strategies for the management and treatment of skin wounds have been developed, the limitations inherent in the current approaches necessitate the development of more effective alternative strategies. Advances in tissue engineering have resulted in the development of novel promising approaches for accelerating wound healing. The use of various biomaterials capable of accelerating the regeneration of damaged tissue is critical in tissue engineering. In this regard, cerium oxide nanoparticles (CeO2 NPs) have recently received much attention because of their excellent biological properties, such as antibacterial, anti-inflammatory, antioxidant, and angiogenic features. The incorporation of CeO2 NPs into various polymer-based scaffolds developed for wound healing applications has led to accelerated wound healing due to the presence of CeO2 NPs. This paper discusses the structure and functions of the skin, the wound healing process, different methods for the synthesis of CeO2 NPs, the biological properties of CeO2 NPs, the role of CeO2 NPs in wound healing, the use of scaffolds containing CeO2 NPs for wound healing applications, and the potential toxicity of CeO2 NPs.

Amygdalin/chitosan-polyvinyl alcohol/cerium-tannic acid hydrogel as biodegradable long-time implant for cancer recurrence care applications: An in vitro study

Cancer recurrence following surgery is a serious and worrying problem for the patient. Common treatment strategies, such as chemotherapy, radiotherapy, and surgery, are restricted because of low uptake of the drugs, poor pharmacokinetic properties, and toxicity issues for healthy tissues. The development of engineering platforms for improving the postoperative treatment of cancer can help solve this problem. In this study, the ceria-tannic acid nanoparticles (CeTA-NPs) were successfully synthesized and characterized. Chitosan-polyvinyl/alcohol (CS-PVA) hydrogels containing CeTA NPs (CS-PVA/CeTA) and amygdalin as an anticancer substance were fabricated using freeze-thaw and immersion-drying techniques. The swelling and degradation behaviors, antibacterial activity, and biocompatibility of as-prepared hydrogel were done. The apoptotic effects of amygdalin/CS-PVA/CeTA hydrogel were evaluated by flow cytometry technique on a human colorectal cancer (SW-480) cell line. The CeTA-NPs were investigated as antibacterial and cross-linker agents for greater stability of the hydrogel network. The CS-PVA/CeTA hydrogel demonstrated good safety and antibacterial activity. The results of swelling and biodegradation suggest that CS-PVA/CeTA hydrogels can inspire long-time application. The anticancer effects of the amygdalin/CS-PVA/CeTA hydrogel were confirmed by apoptosis results. Hence, amygdalin/CS-PVA/CeTA hydrogel can be a promising candidate for long-time biomedical application.

Chitosan-based emulgel and xerogel film containing Thymus pubescens essential oil as a potential wound dressing

Controlling the wound exudates accompanied by microbial wound infections has still remained as one the most challenging clinical issues. Herein, a chitosan/gelatin/polyvinyl alcohol xerogel film containing Thymus pubescens essential oil is fabricated for antimicrobial wound dressing application. The chemical and physical characteristics of the devised formulation is characterized by Fourier transform infrared spectroscopy, scanning electron microscopy, atomic force microscope, and tensile tests. Moreover, swelling capability, water vapour transmission rate, water contact angle, solubility, moisture content, and release properties are also studied. The antimicrobial and antibiofilm tests are performed using the broth microdilution and XTT assay, respectively. The produced formulation shows excellent antimicrobial efficacy against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa and Candida species. It is also demonstrated that the obtained film can reduce (∼80 %) Candida albicans biofilm formation, and its biocompatibility is confirmed with MTT (∼100 %) and hemolysis tests. The antimicrobial activity can be correlated to the microbial membrane attraction for Candida albicans cells, illustrated by flow cytometry. This proposed film with appropriate mechanical strength, high swelling capacity in different pH values (∼200-700 %), controlled release property, and antimicrobial and antioxidant activities as well as biocompatibility can be used as a promising candidate for antimicrobial wound dressing applications.

Recent Advances on Cerium Oxide-Based Biomaterials: Toward the Next Generation of Intelligent Theranostics Platforms

Disease or organ damage due to unhealthy living habits, or accidents, is inevitable. Discovering an efficient strategy to address these problems is urgently needed in the clinic. In recent years, the biological applications of nanotechnology have received extensive attention. Among them, as a widely used rare earth oxide, cerium oxide (CeO2 ) has shown good application prospects in biomedical fields due to its attractive physical and chemical properties. Here, the enzyme-like mechanism of CeO2 is elucidated, and the latest research progress in the biomedical field is reviewed. At the nanoscale, Ce ions in CeO2 can be reversibly converted between +3 and +4. The conversion process is accompanied by the generation and elimination of oxygen vacancies, which give CeO2 the performance of dual redox properties. This property facilitates nano-CeO2 to catalyze the scavenging of excess free radicals in organisms, hence providing a possibility for the treatment of oxidative stress diseases such as diabetic foot, arthritis, degenerative neurological diseases, and cancer. In addition, relying on its excellent catalytic properties, customizable life-signaling factor detectors based on electrochemical techniques are developed. At the end of this review, an outlook on the opportunities and challenges of CeO2 in various fields is provided.

TiO2, CeO2, and TiO2-CeO2 nanoparticles incorporated 2.5D chitosan hydrogels: Gelation behavior and cytocompatibility

In this study, gelation behavior and cytocompatibility of 2.5D chitosan hydrogels were investigated in the presence of TiO2, CeO2 and TiO2-CeO2 composite nanoparticles. Chemical co-precipitation method was used for nanoparticle synthesis and they were heat treated at 600 °C and 700 °C. Gelation of the chitosan solutions was carried out at 37 °C in the presence of glycerol phosphate and genipin as crosslinkers. The gelation time of chitosan was decreased by all of the nanoparticles whereas its elastic modulus was increased by nanoparticles addition. Chitosan solutions containing CeO2 or TiO2-CeO2 nanoparticles showed faster gel formation compared to chitosan solutions containing only TiO2 nanoparticles. CeO2@700 °C nanoparticles decreased the gelation time by 46% and increased elastic modulus by 14%. Average pore diameter of the hydrogel decreased from 127 ± 62 μm to 77 ± 33 μm, water uptake decreased 21% and thermal stability increased in the presence of CeO2@700 °C nanoparticles compared to chitosan hydrogel. Cell viability results indicated that chitosan hydrogels with or without nanoparticles created 2.5D environment supporting cellular proliferation approximately 1.5 times more than TCPS due to their high porous surfaces. Immunofluorescence images were also supported cell viability results. Therefore, CeO2 or TiO2-CeO2 composite nanoparticles incorporated 2.5D chitosan hydrogels may be alternative tissue engineering materials with their fast gelation, ease of use, low cost, light transparency, and cytocompatibility.

Electrospun polyvinyl alcohol-chitosan dressing stimulates infected diabetic wound healing with combined reactive oxygen species scavenging and antibacterial abilities

Diabetic wounds (DW) are constantly challenged by excessive reactive oxygen species (ROS) accumulation and susceptibility to bacterial contamination. Therefore, the elimination of ROS in the immediate vicinity and the eradication of local bacteria are critical to stimulating the efficient healing of diabetic wounds. In the current study, we encapsulated mupirocin (MP) and cerium oxide nanoparticles (CeNPs) into a polyvinyl alcohol/chitosan (PVA/CS) polymer, and then a PVA/chitosan nanofiber membrane wound dressing was fabricated using electrostatic spinning, which is a simple and efficient method for fabricating membrane materials. The PVA/chitosan nanofiber dressing provided a controlled release of MP, which produced rapid and long-lasting bactericidal activity against both methicillin-sensitive S. aureus (MSSA) and methicillin-resistant S. aureus (MRSA) strains. Simultaneously, the CeNPs embedded in the membrane exhibited the desired ROS scavenging capacity to maintain the local ROS at a normal physiological level. Moreover, the biocompatibility of the multifunctional dressing was evaluated both in vitro and in vivo. Taken together, PVA-CS-CeNPs-MP integrated the desirable features of a wound dressing, including rapid and broad-spectrum antimicrobial and ROS scavenging activities, easy application, and good biocompatibility. The results validated the effectiveness of our PVA/chitosan nanofiber dressing, highlighting its promising translational potential in the treatment of diabetic wounds.

Development of Composite Sponge Scaffolds Based on Carrageenan (CRG) and Cerium Oxide Nanoparticles (CeO2 NPs) for Hemostatic Applications

In this study, a novel absorbable hemostatic agent was developed using carrageenan (CRG) as a natural polymer and cerium oxide nanoparticles (CeO2 NPs). CRG-CeO2-0.5 and CRG-CeO2-1 composites were prepared by compositing CeO2 to CRG + CeO2 at a weight ratio of 0.5:100 and 1:100, respectively. The physicochemical and structural properties of these compounds were studied and compared with pristine CRG. Upon incorporation of CeO2 nanoparticles into the CRG matrix, significant reductions in hydrogel degradation were observed. In addition, it was noted that CRG-CeO2 exhibited better antibacterial and hemostatic properties than CRG hydrogel without CeO2 NPs. The biocompatibility of the materials was tested using the NIH 3T3 cell line, and all samples were found to be nontoxic. Particularly, CRG-CeO2-1 demonstrated superior hemostatic effects, biocompatibility, and a lower degradation rate since more CeO2 NPs were present in the CRG matrix. Therefore, CRG-CeO2-1 has the potential to be used as a hemostatic agent and wound dressing.

A calcium peroxide incorporated oxygen releasing chitosan-PVA patch for Diabetic wound healing

Impaired wound healing is a major healthcare problem in patients with diabetes often resulting in gangrene, microbial infection and amputation of affected limb. The delay or absence in healing process arises from several abnormalities, among them chronic hypoxia is a major concern due to its associated issues such as lack of collagen deposition, epithelization, fibroplasia, angiogenesis, and resistance to infections at the wound site. To address hypoxia, delivery of oxygen at the wound site through oxygen releasing agents have been proven to be effective therapeutics. Several oxygen releasing nanoparticles such as Sodium Percarbonate (SPC), Calcium Peroxide (CPO), Hydrogen Peroxide, Magnesium Peroxide (MPO) have been investigated in wound healing application. However, the uncontrolled/burst release of these nanotherapeutic agents and its accompanied cytotoxicity pose a barrier in expediting the healing process. In this study, a Chitosan-Polyvinyl alcohol (CS-PVA) based hydrogel containing oxygen releasing nanoparticle, calcium peroxide (CPO) was constructed to provide a slow and sustained delivery of oxygen for at least 5 days. In-vitro cell culture studies with this material using fibroblast and endothelial cell line exhibited improved biocompatibility, cell viability and enhanced proliferation in comparison with the control group. Additionally, cell migration study using scratch assay method showed superior cell migration ability of our proposed materials. Furthermore, In vivo study using diabetic rat model showed accelerated wound closure rate compared to untreated control wounds.

Applications of drug delivery systems, organic, and inorganic nanomaterials in wound healing

The skin is known to be the largest organ in the human body, while also being exposed to environmental elements. This indicates that skin is highly susceptible to physical infliction, as well as damage resulting from medical conditions such as obesity and diabetes. The wound management costs in hospitals and clinics are expected to rise globally over the coming years, which provides pressure for more wound healing aids readily available in the market. Recently, nanomaterials have been gaining traction for their potential applications in various fields, including wound healing. Here, we discuss various inorganic nanoparticles such as silver, titanium dioxide, copper oxide, cerium oxide, MXenes, PLGA, PEG, and silica nanoparticles with their respective roles in improving wound healing progression. In addition, organic nanomaterials for wound healing such as collagen, chitosan, curcumin, dendrimers, graphene and its derivative graphene oxide were also further discussed. Various forms of nanoparticle drug delivery systems like nanohydrogels, nanoliposomes, nanofilms, and nanoemulsions were discussed in their function to deliver therapeutic agents to wound sites in a controlled manner.

Structural and functional insights in polysaccharides coated cerium oxide nanoparticles and their potential biomedical applications: A review

Cerium oxide nanoparticles have now significant presence in biomedical fields due to their wide applications; however, challenges regarding their safety and biocompatibility persist. Polysaccharides based biopolymers have inherent hydroxyl and carboxyl groups, enabling them to govern the surface functionalization of cerium oxide nanoparticles, hence their chemical and physical characteristics. Because of this, polysaccharides such as dextran, alginate, pullulan, chitosan, polylactic acid, starch, and pectin are practical substitutes for the conventional coatings used to synthesize cerium oxide nanoparticles. This review discusses the effect of biopolymer coatings on the properties of cerium oxide nanoparticles, such as size, stability, aggregation, and biocompatibility. Additionally, it also summarises various biomedical applications of polysaccharides coated cerium oxide nanoparticles, such as in bone tissue regeneration, liver inflammation, wound healing, and antibacterial and anticancer activities. Biocompatible cerium oxide nanoparticles will surely improve their applications in the biomedical field.

Wound healing strategies based on nanoparticles incorporated in hydrogel wound patches

The intricate, tightly controlled mechanism of wound healing that is a vital physiological mechanism is essential to maintaining the skin's natural barrier function. Numerous studies have focused on wound healing as it is a massive burden on the healthcare system. Wound repair is a complicated process with various cell types and microenvironment conditions. In wound healing studies, novel therapeutic approaches have been proposed to deliver an effective treatment. Nanoparticle-based materials are preferred due to their antibacterial activity, biocompatibility, and increased mechanical strength in wound healing. They can be divided into six main groups: metal NPs, ceramic NPs, polymer NPs, self-assembled NPs, composite NPs, and nanoparticle-loaded hydrogels. Each group shows several advantages and disadvantages, and which material will be used depends on the type, depth, and area of the wound. Better wound care/healing techniques are now possible, thanks to the development of wound healing strategies based on these materials, which mimic the extracellular matrix (ECM) microenvironment of the wound. Bearing this in mind, here we reviewed current studies on which NPs have been used in wound healing and how this strategy has become a key biotechnological procedure to treat skin infections and wounds.

A comprehensive review of chitosan applications in paper science and technologies

Using environmentally friendly biomaterials in different aspects of human life has been considered extensively. In this respect, different biomaterials have been identified and different applications have been found for them. Currently, chitosan, the well-known derivative of the second most abundant polysaccharide in the nature (i.e., chitin), has been receiving a lot of attention. This unique biomaterial can be defined as a renewable, high cationic charge density, antibacterial, biodegradable, biocompatible, non-toxic biomaterial with high compatibility with cellulose structure, where it can be used in different applications. This review takes a deep and comprehensive look at chitosan and its derivative applications in different aspects of papermaking.

Graphene quantum dots-hybrid hydrogel as an avant-garde biomimetic scaffold for diabetic wound healing

In the age of fathoming biomedical predicaments, ardently emerged the field of materiobiology to effectively counter the archetypal and outdated therapies. Correspondingly, the subpar activity of the over-the-counter wound dressing pharmaceuticals have been dominated with the implementation of biocompatible, water-retaining exotic hydrogels to facilitate accelerated diabetic wound healing. Considering a strategy to develop a pragmatic biomimetic scaffold having the ability of dynamic wound healing with diminutive inflammation, we investigated the creation of graphene quantum dot (GQD)-polyacrylic acid (PAA) hybrid hydrogel. We observe appropriate percentage of GQD incorporation in PAA to demonstrate lower pro-inflammatory cytokines, interleukin (IL-6), and tumour necrosis factor (TNF-α) along with higher anti-inflammatory (IL-10) expressions in contrast to natural and standard controls. Likewise, histological examinations corresponding to the in-vitro and in-vivo toxicological analysis of GQD-PAA manifested to be a non-toxic, biocompatible saviour of diabetic wounds. This hybrid hydrogel reports the quickest diabetic wound healing of 13 days. Additionally, the hybrid hydrogel also demonstrates salient antibacterial activity against E. coli. We explore a multifaceted mechanistic approach attributed by the hybrid framework as an avant-garde solution in materiobiology and diabetic wound healing nexus. We believe the GQD-hybrid hydrogel reveals an advancement that could portray a new horizon against diabetic wounds.

Transforming Wound Management: Nanomaterials and Their Clinical Impact

Wound healing is a complex process that can be further complicated in chronic wounds, leading to prolonged healing times, high healthcare costs, and potential patient morbidity. Nanotechnology has shown great promise in developing advanced wound dressings that promote wound healing and prevent infection. The review article presents a comprehensive search strategy that was applied to four databases, namely Scopus, Web of Science, PubMed, and Google Scholar, using specific keywords and inclusion/exclusion criteria to select a representative sample of 164 research articles published between 2001 and 2023. This review article provides an updated overview of the different types of nanomaterials used in wound dressings, including nanofibers, nanocomposites, silver-based nanoparticles, lipid nanoparticles, and polymeric nanoparticles. Several recent studies have shown the potential benefits of using nanomaterials in wound care, including the use of hydrogel/nano silver-based dressings in treating diabetic foot wounds, the use of copper oxide-infused dressings in difficult-to-treat wounds, and the use of chitosan nanofiber mats in burn dressings. Overall, developing nanomaterials in wound care has complemented nanotechnology in drug delivery systems, providing biocompatible and biodegradable nanomaterials that enhance wound healing and provide sustained drug release. Wound dressings are an effective and convenient method of wound care that can prevent wound contamination, support the injured area, control hemorrhaging, and reduce pain and inflammation. This review article provides valuable insights into the potential role of individual nanoformulations used in wound dressings in promoting wound healing and preventing infections, and serves as an excellent resource for clinicians, researchers, and patients seeking improved healing outcomes.

A Brief Review on Cerium Oxide (CeO2NPs)-Based Scaffolds: Recent Advances in Wound Healing Applications

The process of wound healing is complex and involves the interaction of multiple cells, each with a distinct role in the inflammatory, proliferative, and remodeling phases. Chronic, nonhealing wounds may result from reduced fibroblast proliferation, angiogenesis, and cellular immunity, often associated with diabetes, hypertension, vascular deficits, immunological inadequacies, and chronic renal disease. Various strategies and methodologies have been explored to develop nanomaterials for wound-healing treatment. Several nanoparticles such as gold, silver, cerium oxide and zinc possess antibacterial properties, stability, and a high surface area that promotes efficient wound healing. In this review article, we investigate the effectiveness of cerium oxide nanoparticles (CeO₂NPs) in wound healing-particularly the effects of reducing inflammation, enhancing hemostasis and proliferation, and scavenging reactive oxygen species. The mechanism enables CeO₂NPs to reduce inflammation, modulate the immunological system, and promote angiogenesis and tissue regeneration. In addition, we investigate the efficacy of cerium oxide-based scaffolds in various wound-healing applications for creating a favorable wound-healing environment. Cerium oxide nanoparticles (CeO₂NPs) exhibit antioxidant, anti-inflammatory, and regenerative characteristics, enabling them to be ideal wound healing material. Investigations have shown that CeO₂NPs can stimulate wound closure, tissue regeneration, and scar reduction. CeO₂NPs may also reduce bacterial infections and boost wound-site immunity. However, additional study is needed to determine the safety and efficacy of CeO₂NPs in wound healing and their long-term impacts on human health and the environment. The review reveals that CeO₂NPs have promising wound-healing properties, but further study is needed to understand their mechanisms of action and ensure their safety and efficacy.

Quaternary ammonium salt-modified isabgol scaffold as an antibacterial dressing to improve wound healing

Chronic wounds require suitable treatment and management strategies for proper healing. Among other causes, infection delays the healing of wounds and increases the risk of wound-related complications. In this study, an inherently antibacterial and biocompatible wound dressing is developed to enhance the healing. Chemical modification of a natural polysaccharide, Isabgol with epoxypropyltrimethylammonium chloride, renders antibacterial activity to the material. This is the first report of such chemical modification of this polymer for biomedical applications. The modified material is freeze-dried to obtain porous scaffolds. ¹³C NMR and FTIR analysis confirmed the modification of the Isabgol polymer chains with EPTMAC. SEM analysis confirmed the porous structure of the scaffold that would allow the exchange of gases and nutrients through the matrix. The material can swell up to 17 times its initial weight, allowing it to absorb wound exudates and maintain a moist environment at the wound site. Thermogravimetric analysis and compression testing showed that the scaffold has suitable thermal and mechanical properties. The material is antibacterial and can potentially prevent infections at the wound site. In vitro studies have confirmed that these scaffolds are cytocompatible and hemocompatible. These properties indicate that the EPTMAC-modified Isabgol scaffolds would be suitable for wound dressing applications.

Biocomposite films based on chitosan and cerium oxide nanoparticles with promising regenerative potential

Polymeric nanocomposite materials have great potential in the development of tissue-engineered scaffolds because they affect the structure and properties of polymeric materials and regulate cell proliferation and differentiation. In this work, cerium oxide nanoparticles (CeONPs) were incorporated into a chitosan (CS) film to improve the proliferation of multipotent mesenchymal stem cells (MSCs). The citrate-stabilized CeONPs with a negative ζ-potential (-25.0 mV) were precoated with CS to obtain positively charged particles (+20.3 mV) and to prevent their aggregation in the composite solution. The composite CS-CeONP films were prepared in the salt and basic forms using a dry-cast process. The films obtained in both forms were characterized by a uniform distribution of CeONPs. The incorporation of CeONPs into the salt form of CS increased the stiffness of the CS-CeONP film, while the subsequent conversion of the film to the basic form resulted in a decrease in both the Young's modulus and the yield stress. The redox activity (Ce⁴⁺ ⇌ Ce³⁺) of cerium oxide in the CS-CeONP film was confirmed by thermal oxidative degradation. In vitro culture of MSCs showed that the CS-CeONP film has good biocompatibility, and in vivo experiments demonstrated its substantial regenerative potential.

Fabrication of chitosan-MnO2‑iridium/nanoceria supported nanoparticles: Catalytic and anti-radical activities

Chitosan capped MnO₂‑iridium nanoparticles supported on nanoceria (Ch-MnO₂-Ir/CeO₂) were fabricated by using combination of colloidal solution and metal displacement galvanic methods. The oxidative degradation of acid orange 7 in aqueous solution by activated persulfate with the as-prepared nanoparticles was studied. The resulting Ch-MnO₂-Ir/CeO₂ with S₂O₈^2-, 80 % degraded 70.06 mg/L of acid orange 7 within 100 min, while at the same time, Ch-Ir, Ch-MnO₂, and Ch-Ir-MnO₂ remained inactive. CeO₂ increased the surface of the catalyst, and also improved the reactive oxygen species site of Ch-Ir-MnO₂ through the activation of S₂O₈^2- with CeO₂. The reversible redox cycle reaction, Ce (III) ↔ Ce (IV) and strong synergistic effect of MnO₂-Ir are responsible for the remarkable catalytic performance of Ch-MnO₂-Ir/CeO₂/S₂O₈^2- system. The degradation of acid orange 7 could be significantly retarded with inorganic (NO₃^- < Cl^- < SO₄^2- < H₂PO₄^- < HCO₃^-) and organic scavengers (ethanol < tertiary butanol < benzoquinone < phenol). Ch-MnO₂-Ir/CeO₂ exhibited excellent stability and reusability. Anti-radical activity of chitosan and Ch-MnO₂-Ir/CeO₂ was evaluated with 2,2-diphenyl-1-picrylhydrazyl (DPPH) free radical. The free radical properties increase with concentration of chitosan and Ch-MnO₂-Ir/CeO₂.

In-vivo processing of nanoassemblies: a neglected framework for recycling to bypass nanotoxicological therapeutics

The proof-of-concept of nanomaterials (NMs) in the fields of imaging, diagnosis, treatment, and theranostics shows the importance in biopharmaceuticals development due to structural orientation, on-targeting, and long-term stability. However, biotransformation of NMs and their modified form in human body via recyclable techniques are not explored owing to tiny structures and cytotoxic effects. Recycling of NMs offers advantages of dose reduction, re-utilization of the administered therapeutics providing secondary release, and decrease in nanotoxicity in human body. Therefore, approaches like in-vivo re-processing and bio-recycling are essential to overcome nanocargo system-associated toxicities such as hepatotoxicity, nephrotoxicity, neurotoxicity, and lung toxicity. After 3-5 stages of recycling process of some NMs of gold, lipid, iron oxide, polymer, silver, and graphene in spleen, kidney, and Kupffer's cells retain biological efficiency in the body. Thus, substantial attention towards recyclability and reusability of NMs for sustainable development necessitates further advancement in healthcare for effective therapy. This review article outlines biotransformation of engineered NMs as a valuable source of drug carriers and biocatalyst with critical strategies like pH modification, flocculation, or magnetization for recovery of NMs in the body. Furthermore, this article summarizes the challenges of recycled NMs and advances in integrated technologies such as artificial intelligence, machine learning, in-silico assay, etc. Therefore, potential contribution of NM's life-cycle in the recovery of nanosystems for futuristic developments require consideration in site-specific delivery, reduction of dose, remodeling in breast cancer therapy, wound healing action, antibacterial effect, and for bioremediation to develop ideal nanotherapeutics.

A nanofiber-hydrogel composite from green synthesized AgNPs embedded to PEBAX/PVA hydrogel and PA/Pistacia atlantica gum nanofiber for wound dressing

A polyamide/Pistacia atlantica (P.a) gum nanofiber, fabricated by electrospinning method, was coated on a layer of PEBAX/PVA hydrogel embedded with green synthesized Ag nanoparticles (AgNPs) and the prepared nanofiber-hydrogel composite was assessed for wound dressing application. The AgNPs were characterized using ultraviolet-visible (UV-Vis), Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), transmission electron microscopy (TEM), and Zeta potential analysis. The PEBAX/PVA/Ag hydrogel, prepared using solution casting method, displayed strong mechanical properties as Young's modulus and the elongation at break for the hydrogel containing AgNPs increased by 12 % and 96 %, respectively. The PEBAX/PVA/Ag hydrogel showed a high antimicrobial activity towards the E. coli (22.8 mm) with no cytotoxicity. The effect of adding the P.a gum on the properties of polyamide nanofiber was investigated using FTIR, SEM, and tensile tests. Samples were assessed by swelling, degradation, and water vapor transfer measurements. Very fine and continuous fibers with average diameters of ≤200 nm were observed by SEM analysis due to the addition of the P.a gum. The result of tensile test indicated that the addition of P.a gum improves the mechanical properties of nanofibers. The physical properties and biocompatibility of the two layers were shown to be complementary when combined.

Curative Effects of Copper Iodide Embedded on Gallic Acid Incorporated in a Poly(vinyl alcohol) (PVA) Liquid Bandage

In daily life, people are often receiving minor cuts due to carelessness, leaving wounds on the skin. If wound healing is interrupted and the healing process does not finish, pathogens can easily enter wounds and cause infection. Liquid bandages are a fast and convenient way to help stop the bleeding of superficial wounds. Moreover, antibacterial agents in liquid bandages can promote wound restoration and fight bacteria. Herein, a poly(vinyl alcohol) (PVA) liquid bandage incorporating copper iodide nanoparticles (CuI NPs) was developed. CuI NPs were synthesized through green synthesis using gallic acid (GA) as a reducing and capping agent. The sizes of the CuI NPs, which were dependent on the concentration of GA, were 41.45, 43.51 and 49.71 nm, with the concentrations of gallic acid being 0, 2.5 mM and 5.0 mM, respectively. CuI NPs were analyzed using FTIR, XRD and SEM and tested for peroxidase-like properties and antibacterial activity. Then, PVA liquid bandages were formulated with different concentrations of stock CuI suspension. The results revealed that PVA liquid bandages incorporating 0.190% CuI synthesized with 5.0 mM of GA can kill bacteria within 24 h and have no harmful effects on human fibroblast cells.

The fabrication and evaluation of silver nanoparticle-based keratin scaffolds

The biotoxicity caused by focus releasing of Ag, which associated with the Ag loading mode, is a problematic issue that need to be solved for practical utilization of the keratin based wound dressing. In this study, keratin/AgNPs blend scaffolds (Ker/Ag) and keratin scaffolds with AgNPs attached on the scaffold's wall surface (Ag@Ker) were prepared. Structure and physical properties of the scaffolds were tested and investigated. In comparison to the Ag@Ker scaffolds, the Ker/Ag scaffolds with uniform dispersion of AgNPs have larger tensile strength and slower degradation rate. Both kind of scaffolds present excellent antibacterial property with 10 μg mL^-1 AgNPs addition, while the Ker/Ag displayed a linear Ag releasing ratio in the first 5-7 days, which is beneficial for obtaining a continuous antibacterial property and avoiding the biotoxicity caused by focus release of Ag. Correspondingly, cytotoxicity assay further reveals that the continuously slow release of Ag of the Ker/Ag scaffolds accelerated the proliferation of cell. Infectious animal models and histological studies showed that the Ker/Ag scaffolds can effectively inhibit the inflammatory response and accelerate epithelialization. Thus, it can be concluded that the Ker/Ag scaffolds with uniform dispersion of AgNPs are more attractive as wound repair materials.

Bacterial Cellulose Composites with Polysaccharides Filled with Nanosized Cerium Oxide: Characterization and Cytocompatibility Assessment

A new biocompatible nanocomposite film material for cell engineering and other biomedical applications has been prepared. It is based on the composition of natural polysaccharides filled with cerium oxide nanoparticles (CeONPs). The preparative procedure consists of successive impregnations of pressed bacterial cellulose (BC) with a sodium alginate (ALG) solution containing nanoparticles of citrate-stabilized cerium oxide and a chitosan (CS) solution. The presence of CeONPs in the polysaccharide composite matrix and the interaction of the nanoparticles with the polymer, confirmed by IR spectroscopy, change the network architecture of the composite. This leads to noticeable changes in a number of properties of the material in comparison with those of the matrix's polysaccharide composition, viz., an increase in mechanical stiffness, a decrease in the degree of planar orientation of BC macrochains, an increase in hydrophilicity, and the shift of the processes of thermo-oxidative destruction of the material to a low-temperature region. The latter effect is considered to be caused by the redox activity of cerium oxide (reversible transitions between the states Ce⁴⁺ and Ce³⁺) in thermally stimulated processes in the nanocomposite films. In the equilibrium swollen state, the material retains a mechanical strength at the level of ~2 MPa. The results of in vitro tests (cultivation of multipotent mesenchymal stem cells) have demonstrated the good biocompatibility of the BC-ALG(CeONP)-CS film as cell proliferation scaffolds.

Development of Antimicrobial nanocomposite scaffolds via Loading CZTSe Quantum Dots for wound dressing applications

The antimicrobial properties of scaffolds designed for use in wound healing are accepted as an important factor in the healing process to accelerate the wound healing process without causing inflammation. For this purpose, Chitosan-PVA composite membranes loaded with Cu2ZnSnSe4 quantum dots (CZTSe QDs) as an antibacterial and cytocompatible biomaterial to regulate the wound healing process were produced. CZTSe QDs particles were synthesized under hydrothermal conditions. Polymer-based nanocomposites with different concentrations of the synthesized nanoparticles were produced by the solvent casting method. After detailed physicochemical and morphological characterizations of CZTSe QDs and composite membranes, antibacterial activities and cell viability were extensively investigated against gram-positive and gram-negative bacterial and yeast strains, and L929 mouse fibroblast cells lines, respectively. The results show that the preparation of composite scaffolds at a QDs concentration of 3.3 % by weight has the best antimicrobial activity. Composite scaffold membranes, which can be obtained as a result of an easy production process, are thought to have great potential applications in tissue engineering as wound dressing material due to their high mechanical properties, wettability, strong antibacterial properties and non-toxicity.

Multifunctional mesoporous silica-cerium oxide nanozymes facilitate miR129 delivery for high-quality healing of radiation-induced skin injury

Radiation-induced skin injury (RISI) is an important challenge for clinical treatments. The main causes of RISI include hypoxia in the wound microenvironment, reactive oxygen species (ROS) activation, and downregulation of DNA repair proteins. Here, a multiple radioresistance strategy was designed for microRNA therapy and attenuating hypoxia. A novel mesoporous silica (MS) firmly anchored and dispersed cerium (IV) oxide (CeO₂) nanoparticles to form MS-CeO₂ nanocomposites, which exhibit superior activity in inhibiting radiation-induced ROS and HIF-1α activation and ultimately promote RISI wound healing. The miR129 serum concentrations in patients can promote radioresistance by directly targeting RAD17 and regulating the Chk2 pathway. Subsequently, MS-CeO₂ nanocomposites with miR129 were conjugated with iRGD-grafted polyoxyethylene glycol (short for nano-miR129), which increased the stability and antibacterial character, efficiently delivered miR129 to wound blood capillaries, and exhibited low toxicity. Notably, nano-miR129 promoted radioresistance and enhanced anti-ROS therapeutic efficacy in a subcutaneous RISI mouse model. Overall, this MS-CeO₂ nanozyme and miR129-based multiresistance radiotherapy protection strategy provided a promising therapeutic approach for RISI.

Significance of Capping Agents of Colloidal Nanoparticles from the Perspective of Drug and Gene Delivery, Bioimaging, and Biosensing: An Insight

The over-growth and coagulation of nanoparticles is prevented using capping agents by the production of stearic effect that plays a pivotal role in stabilizing the interface. This strategy of coating the nanoparticles’ surface with capping agents is an emerging trend in assembling multipurpose nanoparticles that is beneficial for improving their physicochemical and biological behavior. The enhancement of reactivity and negligible toxicity is the outcome. In this review article, an attempt has been made to introduce the significance of different capping agents in the preparation of nanoparticles. Most importantly, we have highlighted the recent progress, existing roadblocks, and upcoming opportunities of using surface modified nanoparticles in nanomedicine from the drug and gene delivery, bioimaging, and biosensing perspectives.

Synthesis and Processing of Dynamic Covalently Crosslinked Polydextran/Carbon Dot Nanocomposite Hydrogels with Tailorable Microstructures and Properties

Using functionalized nanoparticles to crosslink hydrophilic polymers is a growing theme of directly constructing nanocomposite (NC) hydrogels. Employing dynamic covalent chemistry at the nanoparticle-polymer interface is particularly attractive due to the spontaneous formation and reversible manner of dynamic covalent bonds. However, the structure and property modulation of the dynamic covalently crosslinked NC hydrogels has not been thoroughly discussed. Here, we fabricated NC hydrogels by using amine-functionalized carbon dots (CDs) to crosslink polydextran aldehyde (PDA) polymers through imine bond formation. The role of PDA with different oxidation degrees (i.e., PDA10, PDA30, and PDA50) in affecting the microstructures and properties of PDA@CD hydrogels was systematically investigated, showing that the PDA50@CD hydrogel presented the densest structure and the highest mechanical strength among the three PDA@CD hydrogels. The pH-responsiveness, 3D printing, electrospinning, and biocompatibility of PDA@CD hydrogels were also demonstrated, showing the great promise of using PDA@CD hydrogels for applications in biomedicine and biofabrication.