Antibacterial nano cerium oxide/chitosan/cellulose acetate composite films as potential wound dressing

Advances in the preparation and application of cellulose-based antimicrobial materials: A review

The rise of polymer materials in modern life has drawn attention to renewable, easily biodegradable, environmentally-friendly bio-based polymers. Notably, significant research has been dedicated to creating green antimicrobial functional materials for the biomedical field using natural polymer materials. Cellulose is a rich natural biomass organic polymer material. Given its favorable attributes like film-forming capability, biodegradability, and biocompatibility, it is extensively employed to tackle a wide range of challenges confronting humanity today. However, its inherent drawbacks, such as insolubility in water and most organic solvents, hygroscopic nature, difficulty in melting, and limited antimicrobial properties, continue to pose challenges for realizing the high-value applications of cellulose. Achieving multifunctionality and more efficient application of cellulose still poses major challenges. In this regard, the current development status of cellulose materials was reviewed, covering the classification, preparation methods, and application status of cellulose-based antimicrobial materials. The application value of cellulose-based antimicrobial materials in biomedicine, textiles, food packaging, cosmetics and wastewater treatment was summarised. Finally, insights were provided into the developing prospects of cellulose-based antimicrobial materials were provided.

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.

Effective antibacterial agents in modern wound dressings: a review

Wound infections are a significant concern in healthcare, leading to long healing times. Traditional approaches for managing wound infections rely heavily on systemic antibiotics, which are associated with the emergence of antibiotic-resistant bacteria. Therefore, the development of alternative antibacterial materials for wound care has gained considerable attention. In today's world, new generations of wound dressing are commonly used to heal wounds. These new dressings keep the wound and the area around it moist to improve wound healing. However, this moist environment can also foster an environment that is favorable for the growth of bacteria. Excessive antibiotic use poses a significant threat to human health and causes bacterial resistance, so new-generation wound dressings must be designed and developed to reduce the risk of infection. Wound dressings using antimicrobial compounds minimize wound bacterial colonization, making them the best way to avoid open wound infection. We aim to provide readers with a comprehensive understanding of the latest advancements in antibacterial materials for wound management.

Preparation and characterization of chitosan/polyvinyl alcohol antibacterial sponge materials

This study utilized the freeze-drying method to create a chitosan (CS) and polyvinyl alcohol (PVA) sponge. To enhance its antibacterial properties, curcumin and nano silver (Cur@Ag) were added for synergistic antibacterial. After adding curcumin and nano silver, the mechanical properties of the composite sponge dressing (CS-PVA-Cur@Ag) were improved. The porosity of the composite sponge dressing was closed to 80%, which was helpful for drug release, and it had good water absorption and water retention rate. The nano silver diameter was 50-80 nm, which was optimal for killing bacteria. Antibacterial tests usedEscherichia coliandStaphylococcus aureusdemonstrated that little nano silver was required to eliminate bacteria. Finally, in the rat full-thickness skin wound model, the composite sponge dressing can promote wound healing in a short time. In summary, CS-PVA-Cur@Ag wound dressing could protect from bacterial infection and accelerate wound healing. Thus, it had high potential application value for wound dressing.

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.

Coaxial nanofibers encapsulated with Ampelopsis brevipedunculata extract and green synthesized AgNPs for wound repair

Silver nanoparticles (AgNPs) synthesized from Aloe vera extract exhibited a pronounced antibacterial effect, while the Ampelopsis brevipedunculata extract (ABE) showcased a high antioxidant capacity for wound healing. Spherical AgNPs with a particle size of 28.82 nm crystallized in a face-centered-cubic lattice. AgNPs/polyvinyl alcohol (PVA) and ABE/polycaprolactone (PCL) underwent electrospinning to produce coaxial and electrosprayed nanofibers, respectively. The developed coaxial nanofibers demonstrated a strain of 159%, a Young's modulus of elasticity of 7080.14 kPa, a 3.9-fold swelling ratio, a water contact angle of 38.91°, characteristic hydrophilicity, and an adequate water vapor transmission rate of 2272 g/m2/day. ABE exhibited no cytotoxicity to L929 cells and induced a twofold increase in the cell migration rate. Upon applying the developed coaxial nanofiber on an in vivo rat model with a 9 mm wound diameter, the wound rapidly and completely healed within 10 days, with a healing speed 60% greater than that of the control group. Histopathological analysis revealed that the coaxial group did not exhibit inflammation, showed complete epithelization, and featured a well-arranged deposition of collagen on the 10th day.

Cellulose Acetate-Based Wound Dressings Loaded with Bioactive Agents: Potential Scaffolds for Wound Dressing and Skin Regeneration

Wound healing and skin regeneration are major challenges in chronic wounds. Among the types of wound dressing products currently available in the market, each wound dressing material is designed for a specific wound type. Some of these products suffer from various shortcomings, such as poor antibacterial efficacy and mechanical performance, inability to provide a moist environment, poor permeability to oxygen and capability to induce cell migration and proliferation during the wound healing process. Hydrogels and nanofibers are widely reported wound dressings that have demonstrated promising capability to overcome these shortcomings. Cellulose acetate is a semisynthetic polymer that has attracted great attention in the fabrication of hydrogels and nanofibers. Loading bioactive agents such as antibiotics, essential oils, metallic nanoparticles, plant extracts, and honey into cellulose acetate-based nanofibers and hydrogels enhanced their biological effects, including antibacterial, antioxidant, and wound healing. This review reports cellulose acetate-based hydrogels and nanofibers loaded with bioactive agents for wound dressing and skin regeneration.

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.

Chitosan Hydrogels Crosslinked with Oxidized Sucrose for Antimicrobial Applications

Oxidized sucrose (OS) reacts with amino-group-containing polysaccharides, including chitosan, without catalyst, resulting in hydrogels entirely composed of carbohydrates. The presence of imine bonds with low structural stabilities and unreacted aldehydes in the structures of these hydrogels hinder their application as biomaterials. Therefore, herein, the chitosan hydrogels (CTSGs) obtained after the crosslinking of chitosan with OS were reduced using sodium borohydride to convert imine bonds to secondary amines and aldehydes to alcohols. The structures of CTSGs were comprehensively characterized using Fourier transform infrared and 13C nuclear magnetic resonance spectroscopies, and the results implied that the degree of crosslinking (CR) depended on the OS feed amount used during CTSG preparation. The properties of CTSGs were significantly dependent on CR; with an increase in CR, the thermal stabilities and dynamic moduli of CTSGs increased, whereas their swelling properties decreased. CTSGs exhibited antimicrobial properties against the gram-negative bacterium Escherichia coli, and their performances were also dependent on CR. The results indicated the potentials of CTSGs completely based on carbohydrates as antimicrobial hydrogels for various medical and pharmaceutical applications. We believe that this study will contribute to the development of hydrogels for application in the food, medical, and pharmaceutical fields.

Electrospun PVA Fibers for Drug Delivery: A Review

Innovation in biomedical science is always a field of interest for researchers. Drug delivery, being one of the key areas of biomedical science, has gained considerable significance. The utilization of simple yet effective techniques such as electrospinning has undergone significant development in the field of drug delivery. Various polymers such as PEG (polyethylene glycol), PLGA (Poly(lactic-co-glycolic acid)), PLA(Polylactic acid), and PCA (poly(methacrylate citric acid)) have been utilized to prepare electrospinning-based drug delivery systems (DDSs). Polyvinyl alcohol (PVA) has recently gained attention because of its biocompatibility, biodegradability, non-toxicity, and ideal mechanical properties as these are the key factors in developing DDSs. Moreover, it has shown promising results in developing DDSs individually and when combined with natural and synthetic polymers such as chitosan and polycaprolactone (PCL). Considering the outstanding properties of PVA, the aim of this review paper was therefore to summarize these recent advances by highlighting the potential of electrospun PVA for drug delivery systems.

Polymer-Based Hydrogel Loaded with Honey in Drug Delivery System for Wound Healing Applications

Excellent wound dressings should have crucial components, including high porosity, non-toxicity, high water absorption, and the ability to retain a humid environment in the wound area and facilitate wound healing. Unfortunately, current wound dressings hamper the healing process, with poor antibacterial, anti-inflammatory, and antioxidant activity, frequent dressing changes, low biodegradability, and poor mechanical properties. Hydrogels are crosslinked polymer chains with three-dimensional (3D) networks that have been applicable as wound dressings. They could retain a humid environment on the wound site, provide a protective barrier against pathogenic infections, and provide pain relief. Hydrogel can be obtained from natural, synthetic, or hybrid polymers. Honey is a natural substance that has demonstrated several therapeutic efficacies, including anti-inflammatory, antibacterial, and antioxidant activity, which makes it beneficial for wound treatment. Honey-based hydrogel wound dressings demonstrated excellent characteristics, including good biodegradability and biocompatibility, stimulated cell proliferation and reepithelization, inhibited bacterial growth, and accelerated wound healing. This review aimed to demonstrate the potential of honey-based hydrogel in wound healing applications and complement the studies accessible regarding implementing honey-based hydrogel dressing for wound healing.

PGS/Gelatin Nanocomposite Electrospun Wound Dressing

Infectious diabetic wounds can result in severe injuries or even death. Biocompatible wound dressings offer one of the best ways to treat these wounds, but creating a dressing with a suitable hydrophilicity and biodegradation rate can be challenging. To address this issue, we used the electrospinning method to create a wound dressing composed of poly(glycerol sebacate) (PGS) and gelatin (Gel). We dissolved the PGS and Gel in acetic acid (75 v/v%) and added EDC/NHS solution as a crosslinking agent. Our measurements revealed that the scaffolds' fiber diameter ranged from 180.2 to 370.6 nm, and all the scaffolds had porosity percentages above 70%, making them suitable for wound healing applications. Additionally, we observed a significant decrease (p < 0.05) in the contact angle from 110.8° ± 4.3° for PGS to 54.9° ± 2.1° for PGS/Gel scaffolds, indicating an improvement in hydrophilicity of the blend scaffold. Furthermore, our cell viability evaluations demonstrated a significant increase (p < 0.05) in cultured cell growth and proliferation on the scaffolds during the culture time. Our findings suggest that the PGS/Gel scaffold has potential for wound healing applications.

Comparative physical, antioxidant, and antimicrobial properties of films prepared by dissolving chitosan in bioactive vinegar varieties

Solvent casting following the dissolution of chitosan in aqueous acetic acid is the most widely used method for preparing chitosan films. In this study, an economical and practical way is proposed to improve the physicochemical properties of chitosan films by using vinegar varieties both as solvents and as bioactive additives to improve the properties of the films. Chitosan films were prepared by dissolving chitosan in pomegranate, grape, apple, and hawthorn vinegar. Vinegar contains bioactive phenolics and different organic acids together with acetic acid, depending on the main raw material from which it is obtained. The films' mechanical, optical properties, antioxidant and antimicrobial activities were compared with each other and with the chitosan film prepared by dissolving chitosan in acetic acid. The antioxidant and antimicrobial properties of chitosan films prepared with vinegar increased. The use of vinegar as a solvent increased the UV light barrier properties of the films. Improved antimicrobial, antioxidant, optical, and elastic properties of films prepared by dissolving chitosan in vinegar varieties are promising in applications of these films as potential and economic food packaging materials.

Removal of fluoride ions from water by cerium-carboxymethyl cellulose beads doped with CeO2 nanoparticles

A novel adsorbent for fluoride ions (F^-) removal was prepared from cerium ion cross-linked carboxymethyl cellulose (CMC) biopolymer beads loaded with CeO₂ nanoparticles (NPs). The characterization of the beads was performed by swelling experiments, scanning electron microscopy and Fourier transforms infrared spectroscopy. The adsorption of fluoride ions from aqueous solutions was carried out with both cerium ion cross-linked CMC beads (CMCCe) and CeO₂-NPs added beads (CeO₂-CMC-Ce) in a batch system. Optimized adsorption conditions were obtained by testing the parameters such as pH, contact time, adsorbent dose, and shaking rate at 25 °C. The adsorption process is well described by the Langmuir isotherm and pseudo-second-order kinetics. The maximum adsorption capacity was found as 105 and 312 mg/g F^- for CMC-Ce and CeO₂-CMC-Ce beads, respectively. Reusability studies showed that, the adsorbent beads have exhibited excellent sustainable properties up to 9 cycle usage. This study suggests that, CMC-Ce composite with CeO₂ nanoparticles is a very effective adsorbent in removing fluoride from water.

Efficient Photocatalytic Degradation of Methylene Blue Dye from Aqueous Solution with Cerium Oxide Nanoparticles and Graphene Oxide-Doped Polyacrylamide

A cerium oxide nanoparticles (CeO₂-NPs)/graphene oxide (GO)/polyacrylamide (PAM) ternary composite was synthesized through free-radical polymerization of acrylamide in the presence of CeO₂ nanoparticles and GO in an aqueous system. The synthesized composite material was characterized by X-ray diffraction (XRD), Fourier transform infrared (FTIR) spectroscopy, scanning electron microscopy (SEM), and energy-dispersive X-ray (EDX) spectroscopy techniques and applied for the photocatalytic degradation of methylene blue (MB) dye from an aqueous solution. Tauc's model for direct transition was used to model for the optical band gap. The key operating parameters such as the amounts of CeO₂-NPs and GO, pH, initial MB concentration, type of light irradiation, and contact time have been optimized to achieve the highest MB degradation percentage. The photocatalysis process was pH-dependent, and the optimum pH value was found to be 12.0. Under UV-A light, 90% dye degradation occurred in 90 min. The degradation of MB was also specified in terms of total organic carbon (TOC) and chemical oxygen demand (COD). Free-radical capture experiments were also performed to determine the role of radical species during the photocatalytic oxidation process. The photocatalytic process showed that the equilibrium data is in good agreement with the Langmuir-Hinshelwood kinetic model. A rate constant of 0.0259 min^-1 was obtained. The hydrogel was also tested to assess its reusability, which is an important key factor in practical wastewater treatment. The photocatalytic activity only decreased to 75% after nine uses.

Polymer-Based Nanostructures for Pancreatic Beta-Cell Imaging and Non-Invasive Treatment of Diabetes

Diabetes poses major economic, social, and public health challenges in all countries worldwide. Besides cardiovascular disease and microangiopathy, diabetes is a leading cause of foot ulcers and lower limb amputations. With the continued rise of diabetes prevalence, it is expected that the future burden of diabetes complications, early mortality, and disabilities will increase. The diabetes epidemic is partly caused by the current lack of clinical imaging diagnostic tools, the timely monitoring of insulin secretion and insulin-expressing cell mass (beta (β)-cells), and the lack of patients' adherence to treatment, because some drugs are not tolerated or invasively administrated. In addition to this, there is a lack of efficient topical treatment capable of stopping the progression of disabilities, in particular for treating foot ulcers. In this context, polymer-based nanostructures garnered significant interest due to their tunable physicochemical characteristics, rich diversity, and biocompatibility. This review article emphasizes the last advances and discusses the prospects in the use of polymeric materials as nanocarriers for β-cell imaging and non-invasive drug delivery of insulin and antidiabetic drugs in the management of blood glucose and foot ulcers.

Development and Characterization of Electrospun Poly(3-hydroxybutyrate-co-3-hydroxyvalerate) Biopapers Containing Cerium Oxide Nanoparticles for Active Food Packaging Applications

Food quality is mainly affected by oxygen through oxidative reactions and the proliferation of microorganisms, generating changes in its taste, odor, and color. The work presented here describes the generation and further characterization of films with active oxygen scavenging properties made of poly(3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) loaded with cerium oxide nanoparticles (CeO₂NPs) obtained by electrospinning coupled to a subsequent annealing process, which could be used as coating or interlayer in a multilayer concept for food packaging applications. The aim of this work is to explore the capacities of these novel biopolymeric composites in terms of O₂ scavenging capacity, as well as antioxidant, antimicrobial, barrier, thermal, and mechanical properties. To obtain such biopapers, different ratios of CeO₂NPs were incorporated into a PHBV solution with hexadecyltrimethylammonium bromide (CTAB) as a surfactant. The produced films were analyzed in terms of antioxidant, thermal, antioxidant, antimicrobial, optical, morphological and barrier properties, and oxygen scavenging activity. According to the results, the nanofiller showed some reduction of the thermal stability of the biopolyester but exhibited antimicrobial and antioxidant properties. In terms of passive barrier properties, the CeO₂NPs decreased the permeability to water vapor but increased the limonene and oxygen permeability of the biopolymer matrix slightly. Nevertheless, the oxygen scavenging activity of the nanocomposites showed significant results and improved further by incorporating the surfactant CTAB. The PHBV nanocomposite biopapers developed in this study appear as very interesting constituents for the potential design of new active organic recyclable packaging materials.

Wound healing and antibacterial capability of electrospun polyurethane nanofibers incorporating Calendula officinalis and Propolis extracts

In order to produce a healing accelerator antibacterial wound dressing, different electrospun polyurethane (PU)-based nanofibers inclusive Calendula officinalis and Propolis ethanolic extracts were fabricated. The measurement of minimum inhibitory concentrations (MIC) against Methicillin-resistant Staphylococcus aureus (MRSA) determined the concentrations of incorporating extracts. Then the morphological properties of the produced polyurethane (PU), polyurethane/C. officinalis (PU/CO), polyurethane/Propolis (PU/PR), polyurethane/C. officinalis/Propolis (PU/CO/PR) were analyzed by scanning electron microscopy (SEM). The physicochemical features and biological characteristics of the fabricated nanofibers were evaluated. Subsequently, the antibacterial and wound-healing efficiency of electrospun wound dressings were tested under in vivo situation. The electrospun PU/CO/PR nanofiber illustrated the most degree of antibacterial, antioxidant, and cell proliferation efficiencies. In vivo examination and histological analysis confirmed significant improvement in the complete, well-organized wound-healing process in MRSA-infected wounds treated with PU/CO/PR. These outcomes described PU/CO/PR electrospun nanofibers as a wound dressing that can significantly facilitate wound healing with notable antibacterial, antioxidant, and cell proliferation properties.

Cellulose-Acetate-Based Films Modified with Ag2O and ZnS as Nanocomposites for Highly Controlling Biological Behavior for Wound Healing Applications

For wound healing, functional films with certain physicochemical and biological properties are needed. Thus, the current work aimed to fabricate multifunctional materials comprising metal oxide nanoparticles loaded with an efficient polymer to be used as dressing material. A composite containing polymeric phases of cellulose acetate (CA) blended with zinc sulfide (ZnS), silver oxide (Ag₂O), and graphene oxide (GO) was successfully synthesized. The prepared composite crystallinity was studied using the X-ray diffraction technique (XRD). Further, the functional groups and the elemental analysis were investigated using Fourier-transform infrared spectroscopy (FTIR) and energy-dispersive X-ray spectroscopy (EDX). Furthermore, the surface morphology was studied using scanning electron microscopy (SEM) to obtain the shape and size of particles. SEM showed that the particles were formed in wide distribution in the range of 18-915 nm with an average size of 235 nm for Ag₂O/ZnS/GO/CA. The particle size of Ag₂O in the CA film was in the range between 19 and 648 nm with an average size of 216 nm, while the particle size of ZnS in CA was in the range of 12-991 nm with an average age particle size of 158 mm. In addition, EDX, based on SEM investigation, detected high carbon and oxygen quantities at around 94.21% of the composite. The contact angle decreased and reached 26.28° ± 2.12° in Ag₂O/ZnS/CA. Furthermore, thermogravimetric analysis (TGA) was used to investigate the thermal stability, and the composition was thermally stable until 300 °C. Moreover, the cell viability of "normal lung cells" reached 102.66% in vitro at a concentration of 1250 µg/mL. The antibacterial activity of Ag₂O/ZnS/GO/CA was also detected against E. coli with a zone of inhibition reaching 17.7 ± 0.5 mm. Therefore, the composite can be used in biomedical applications due to its biocompatibility and antibacterial activity.

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.

Novel Features of Cellulose-Based Films as Sustainable Alternatives for Food Packaging

Packaging plays an important role in food quality and safety, especially regarding waste and spoilage reduction. The main drawback is that the packaging industry is among the ones that is highly dependent on plastic usage. New alternatives to conventional plastic packaging such as biopolymers-based type are mandatory. Examples are cellulose films and its derivatives. These are among the most used options in the food packaging due to their unique characteristics, such as biocompatibility, environmental sustainability, low price, mechanical properties, and biodegradability. Emerging concepts such as active and intelligent packaging provides new solutions for an extending shelf-life, and it fights some limitations of cellulose films and improves the properties of the packaging. This article reviews the available cellulose polymers and derivatives that are used as sustainable alternatives for food packaging regarding their properties, characteristics, and functionalization towards active properties enhancement. In this way, several types of films that are prepared with cellulose and their derivatives, incorporating antimicrobial and antioxidant compounds, are herein described, and discussed.

Highlighting the Compositional Changes of the Sm2O3/MgO-Containing Cellulose Acetate Films for Wound Dressings

The development of wound dressing materials with appropriate specifications is still a challenge to overcome the current limitations of conventional medical bandages. In this regard, simple and fast methods are highly recommended, such as film casting. In addition, deliverable nanoparticles that can act to accelerate wound integration, such as samarium oxide (Sm₂O₃) and magnesium oxide (MgO), might represent a potential design with a novel compositional combination. In the present research, the casted film of cellulose acetate (CA) was mixed with different ratios of metal oxides, such as samarium oxide (Sm₂O₃) and magnesium oxide (MgO). The tests used for the film examination were X-ray diffraction (XRD), Fourier-transform infrared spectroscopy (FTIR), and scanning electron microscopy (SEM). The SEM graphs of CA films represent the surface morphology of Sm₂O₃@CA, MgO@CA, and Sm₂O₃/MgO/GO@CA. It was found that the scaffolds' surface contained a high porosity ratio with diameters of 1.5-5 µm. On the other hand, the measurement of contact angle exhibits a variable trend starting from 27° to 29° for pristine CA and Sm₂O₃/MgO/GO@CA. The cell viability test exhibits a noticeable increase in cell growth with a decrease in the concentration. In addition, the IC₅₀ was determined at 6 mg/mL, while the concentration of scaffolds of 20 mg/mL caused cellular growth to be around 106%.

Thermally Treated Berberine-Loaded SA/PVA/PEO Electrospun Microfiber Membranes for Antibacterial Wound Dressings

This study aimed to develop a safe and advanced antibacterial material of electrospun microfiber membranes (MFMs) for wound dressings. Combinations of several materials were investigated; thermal treatment and electrospinning techniques were used to form the best quality of MFMs to suit its end applications. By comparing the fiber morphology, diameter changes, and fracture strength, the suitable ratio of raw materials and thermal treatment were obtained before and after adding Trition X-100 as a surfactant for MFMs of sodium alginate/polyvinyl alcohol/polyethylene oxide (SA/PVA/PEO). The electrospinning solution was mixed with berberine as an antibacterial substance; meanwhile, calcium chloride (CaCl₂) was used as the crosslinking agent. The antibacterial properties, water dissolution resistance, water content, and fracture strength were thoroughly investigated. The results showed that the antibacterial rates of MFMs with different mass fractions of berberine (0, 3, and 5 wt.%) to Escherichia coli (E. coli) were 14.7, 92.9, and 97.2%, respectively. The moisture content and fracture strength of MFMs containing 5 wt.% berberine were 72.0% and 7.8 MPa, respectively. In addition, the produced MFMs embodied great water dissolution resistance. Berberine-loaded SA/PVA/PEO MFMs could potentially serve as an antibacterial wound dressing substrate with low cost and small side effects.

Cationized silica ceria nanocomposites to target biofilms in chronic wounds

Altered wound healing is a major challenge faced by both developed and developing nations. Biofilm formation has been identified as one of the causative factors for the progression of chronic wounds. The spread of biofilm is controlled by inhibiting the biofilm formation or disrupting the mature biofilm. Functional nanomaterials/enzymes with antimicrobial effects, such as metal oxides, rare earth metals, and carbon nanoparticles have been investigated to treat biofilm and overcome the drawbacks associated with the antibiotic therapy. Cerium oxide nanoparticles (CNPs) have drawn significant attention as a promising antimicrobial agent owing to their antibacterial, enzyme-mimetic, and crystalline properties but they suffer from poor colloidal stability and dispersity in an aqueous environment and size-dependent function. In this work, we have developed a functionalized silica ceria nanocomposite (FSC), as an antibiotic-free system, to treat biofilms. The FSC possesses a high surface area of mesoporous silica nanoparticles (MSNs) combined with the intrinsic antibacterial activity of cerium oxide for biofilm inhibition. The nanocomposite was fabricated using silica and ceria precursors, and it exhibited a high surface area of 436 m²/g and an average particle size of around 450 nm. The physical and chemical properties of nanocomposite were characterized using FTIR, XRD, UV-Vis, BET, EDX, and XPS analysis. It exhibited a potent antioxidant activity (86%), positive haloperoxidase mimetic property, and broad-spectrum antibacterial activities. It showed 99.9% inhibition against S. aureus (Gram-positive) and 81% inhibition against E. coli (Gram-negative) within 12 and 24 h along with the significant inhibition of biofilm formation (80%) as well as the disruptive effect against the established biofilm (77%) of S. aureus. Cell viability assays indicated the proliferative nature of composite in normal basal conditions and increased cell viability (97%) in the presence of oxidative stress. Despite being a cationic nanomaterial, it showed a good hemocompatibility against human blood and caused complete wound closure in mouse fibroblast cell line within 24 h. The functionalized silica ceria nanocomposite developed has a strong potential in chronic wound healing applications.

Polymeric biomaterials for wound healing applications: a comprehensive review

Chronic wounds have been a global health threat over the past few decades, requiring urgent medical and research attention. The factors delaying the wound-healing process include obesity, stress, microbial infection, aging, edema, inadequate nutrition, poor oxygenation, diabetes, and implant complications. Biomaterials are being developed and fabricated to accelerate the healing of chronic wounds, including hydrogels, nanofibrous, composite, foam, spongy, bilayered, and trilayered scaffolds. Some recent advances in biomaterials development for healing both chronic and acute wounds are extensively compiled here. In addition, various properties of biomaterials for wound-healing applications and how they affect their performance are reviewed. Based on the recent literature, trilayered constructs appear to be a convincing candidate for the healing of chronic wounds and complete skin regeneration because they mimic the full thickness of skin: epidermis, dermis, and the hypodermis. This type of scaffold provides a dense superficial layer, a bioactive middle layer, and a porous lower layer to aid the wound-healing process. The hydrophilicity of scaffolds aids cell attachment, cell proliferation, and protein adhesion. Other scaffold characteristics such as porosity, biodegradability, mechanical properties, and gas permeability help with cell accommodation, proliferation, migration, differentiation, and the release of bioactive factors.

Arabinoxylan-Carboxymethylcellulose Composite Films for Antibiotic Delivery to Infected Wounds

Modern dressings should provide for local delivery of antibiotics and protect the wound from bacterial infection, dehydration and environmental factors to achieve optimal healing. The local delivery of antibiotics can reduce adverse effects and resistance challenges. In this study, we fabricated film dressings composed of arabinoxylan (AX) from Plantago ovata seed husks and carboxymethylcellulose (CMC) by a solvent cast method for the delivery of the antibiotic amikacin (AMK). To determine the suitability of the prepared AX-CMC composite films as wound dressings and drug delivery materials, their physical, chemical, mechanical, morphological, thermal, pharmaceutical, antimicrobial, cytocompatible, and drug delivery properties were investigated. The results demonstrated that the dressings were suitable for delivering the drug at the wound site in a sustained manner and keeping the environment moist for rapid healing. The AMK-loaded AX-CMC films exhibited controlled release of AMK, excellent antibacterial activity, and cytocompatibility. Thus, the AX-CMC composite films appear to be promising bioactive dressing materials for the prevention of wound infections.

The Use of Cerium Compounds as Antimicrobials for Biomedical Applications

Cerium and its derivatives have been used as remedies for wounds since the early 20th century. Cerium nitrate has attracted most attention in the treatment of deep burns, followed later by reports of its antimicrobial properties. Its ability to mimic and replace calcium is presumed to be a major mechanism of its beneficial action. However, despite some encouraging results, the overall data are somewhat confusing with seemingly the same compounds yielding opposing results. Despite this, cerium nitrate is currently used in wound treatment in combination with silver sulfadiazine as Flammacérium. Cerium oxide, especially in nanoparticle form (Nanoceria), has lately captured much interest due to its antibacterial properties mediated via oxidative stress, leading to an increase of published reports. The properties of Nanoceria depend on the synthesis method, their shape and size. Recently, the green synthesis route has gained a lot of interest as an alternative environmentally friendly method, resulting in production of effective antimicrobial and antifungal nanoparticles. Unfortunately, as is the case with antibiotics, emerging bacterial resistance against cerium-derived nanoparticles is a growing concern, especially in the case of bacterial biofilm. However, diverse strategies resulting from better understanding of the biology of cerium are promising. The aim of this paper is to present the progress to date in the use of cerium compounds as antimicrobials in clinical applications (in particular wound healing) and to provide an overview of the mechanisms of action of cerium at both the cellular and molecular level.

Polymer-Based Wound Dressing Materials Loaded with Bioactive Agents: Potential Materials for the Treatment of Diabetic Wounds

Diabetic wounds are severe injuries that are common in patients that suffer from diabetes. Most of the presently employed wound dressing scaffolds are inappropriate for treating diabetic wounds. Improper treatment of diabetic wounds usually results in amputations. The shortcomings that are related to the currently used wound dressings include poor antimicrobial properties, inability to provide moisture, weak mechanical features, poor biodegradability, and biocompatibility, etc. To overcome the poor mechanical properties, polymer-based wound dressings have been designed from the combination of biopolymers (natural polymers) (e.g., chitosan, alginate, cellulose, chitin, gelatin, etc.) and synthetic polymers (e.g., poly (vinyl alcohol), poly (lactic-co-glycolic acid), polylactide, poly-glycolic acid, polyurethanes, etc.) to produce effective hybrid scaffolds for wound management. The loading of bioactive agents or drugs into polymer-based wound dressings can result in improved therapeutic outcomes such as good antibacterial or antioxidant activity when used in the treatment of diabetic wounds. Based on the outstanding performance of polymer-based wound dressings on diabetic wounds in the pre-clinical experiments, the in vivo and in vitro therapeutic results of the wound dressing materials on the diabetic wound are hereby reviewed.

Bioactive Chitosan-Based Organometallic Scaffolds for Tissue Engineering and Regeneration

Captivating achievements in developing advanced hybrid biostructures through integrating natural biopolymers with inorganic materials (e.g., metals and metalloids) have paved the way towards the application of bioactive organometallic scaffolds (OMSs) in tissue engineering and regenerative medicine (TERM). Of various biopolymers, chitosan (CS) has been used widely for the development of bioactive OMSs, in large part due to its unique characteristics (e.g., biocompatibility, biodegradability, surface chemistry, and functionalization potential). In integration with inorganic elements, CS has been used to engineer advanced biomimetic matrices to accommodate both embedded cells and drug molecules and serve as scaffolds in TERM. The use of the CS-based OMSs is envisioned to provide a new pragmatic potential in TERM and even in precision medicine. In this review, we aim to elaborate on recent achievements in a variety of CS/metal, CS/metalloid hybrid scaffolds, and discuss their applications in TERM. We also provide comprehensive insights into the formulation, surface modification, characterization, biocompatibility, and cytotoxicity of different types of CS-based OMSs.

Electrospun Antibacterial Nanomaterials for Wound Dressings Applications

Chronic wounds are caused by bacterial infections and create major healthcare discomforts; to overcome this issue, wound dressings with antibacterial properties are to be utilized. The requirements of antibacterial wound dressings cannot be fulfilled by traditional wound dressing materials. Hence, to improve and accelerate the process of wound healing, an antibacterial wound dressing is to be designed. Electrospun nanofibers offer a promising solution to the management of wound healing, and numerous options are available to load antibacterial compounds onto the nanofiber webs. This review gives us an overview of some recent advances of electrospun antibacterial nanomaterials used in wound dressings. First, we provide a brief overview of the electrospinning process of nanofibers in wound healing and later discuss electrospun fibers that have incorporated various antimicrobial agents to be used in wound dressings. In addition, we highlight the latest research and patents related to electrospun nanofibers in wound dressing. This review also aims to concentrate on the importance of nanofibers for wound dressing applications and discuss functionalized antibacterial nanofibers in wound dressing.

Marine Polysaccharides for Wound Dressings Application: An Overview

Wound dressings have become a crucial treatment for wound healing due to their convenience, low cost, and prolonged wound management. As cutting-edge biomaterials, marine polysaccharides are divided from most marine organisms. It possesses various bioactivities, which allowing them to be processed into various forms of wound dressings. Therefore, a comprehensive understanding of the application of marine polysaccharides in wound dressings is particularly important for the studies of wound therapy. In this review, we first introduce the wound healing process and describe the characteristics of modern commonly used dressings. Then, the properties of various marine polysaccharides and their application in wound dressing development are outlined. Finally, strategies for developing and enhancing marine polysaccharide wound dressings are described, and an outlook of these dressings is given. The diverse bioactivities of marine polysaccharides including antibacterial, anti-inflammatory, haemostatic properties, etc., providing excellent wound management and accelerate wound healing. Meanwhile, these biomaterials have higher biocompatibility and biodegradability compared to synthetic ones. On the other hand, marine polysaccharides can be combined with copolymers and active substances to prepare various forms of dressings. Among them, emerging types of dressings such as nanofibers, smart hydrogels and injectable hydrogels are at the research frontier of their development. Therefore, marine polysaccharides are essential materials in wound dressings fabrication and have a promising future.

Engineering the Multi-Enzymatic Activity of Cerium Oxide Nanoparticle Coatings for the Antioxidant Protection of Implants

Imbalance of oxidants is a universal contributor to the failure of implanted devices and tissues. A sustained oxidative environment leads to cytotoxicity, prolonged inflammation, and ultimately host rejection of implanted devices/grafts. The incorporation of antioxidant materials can inhibit this redox/inflammatory cycle and enhance implant efficacy. Cerium oxide nanoparticles (CONP) is a highly promising agent that exhibits potent, ubiquitous, and self-renewable antioxidant properties. Integrating CONP as surface coatings provides ease in translating antioxidant properties to various implants/grafts. Herein, we describe the formation of CONP coatings, generated via the sequential deposition of CONP and alginate, and the impact of coating properties, pH, and polymer molecular weight, on their resulting redox profile. Investigation of CONP deposition, layer formation, and coating uniformity/thickness on their resulting oxidant scavenging activity identified key parameters for customizing global antioxidant properties. Results found lower molecular weight alginates and physiological pH shift CONP activity to a higher H2O2 to O2 --scavenging capability. The antioxidant properties measured for these various coatings translated to distinct antioxidant protection to the underlying encapsulated cells. Information gained from this work can be leveraged to tailor coatings towards specific oxidant-scavenging applications and prolong the function of medical devices and cellular implants.

Bacterial Cellulose-Based Nanocomposites Containing Ceria and Their Use in the Process of Stem Cell Proliferation

A technique for the fabrication of bacterial cellulose-based films with CeO₂ nanofiller has been developed. The structural and morphological characteristics of the materials have been studied, their thermal and mechanical properties in dry and swollen states having been determined. The preparation methodology makes it possible to obtain composites with a uniform distribution of nanoparticles. The catalytic effect of ceria, regarding the thermal oxidative destruction of cellulose, has been confirmed by TGA and DTA methods. An increase in CeO₂ content led to an increase in the elastic modulus (a 1.27-fold increase caused by the introduction of 5 wt.% of the nanofiller into the polymer) and strength of the films. This effect is explained by the formation of additional links between polymer macro-chains via the nanoparticles’ surface. The materials fabricated were characterized by a limited ability to swell in water. Swelling caused a 20- to 30-fold reduction in the stiffness of the material, the mechanical properties of the films in a swollen state remaining germane to their practical use. The application of the composite films in cell engineering as substrates for the stem cells’ proliferation has been studied. The increase in CeO₂ content in the films enhanced the proliferative activity of embryonic mouse stem cells. The cells cultured on the scaffold containing 5 wt.% of ceria demonstrated increased cell survival and migration activity. An analysis of gene expression confirmed improved cultivation conditions on CeO₂-containing scaffolds.

Biopolymer and Synthetic Polymer-Based Nanocomposites in Wound Dressing Applications: A Review

Biopolymers are materials obtained from a natural origin, such as plants, animals, microorganisms, or other living beings; they are flexible, elastic, or fibrous materials. Polysaccharides and proteins are some of the natural polymers that are widely used in wound dressing applications. In this review paper, we will provide an overview of biopolymers and synthetic polymer-based nanocomposites, which have promising applications in the biomedical research field, such as wound dressings, wound healing, tissue engineering, drug delivery, and medical implants. Since these polymers have intrinsic biocompatibility, low immunogenicity, non-toxicity, and biodegradable properties, they can be used for various clinical applications. The significant advancements in materials research, drug development, nanotechnology, and biotechnology have laid the foundation for changing the biopolymeric structural and functional properties. The properties of biopolymer and synthetic polymers were modified by blending them with nanoparticles, so that these materials can be used as a wound dressing application. Recent wound care issues, such as tissue repairs, scarless healing, and lost tissue integrity, can be treated with blended polymers. Currently, researchers are focusing on metal/metal oxide nanomaterials such as zinc oxide (ZnO), cerium oxide (CeO₂), silver (Ag), titanium oxide (TiO₂), iron oxide (Fe₂O₃), and other materials (graphene and carbon nanotubes (CNT)). These materials have good antimicrobial properties, as well as action as antibacterial agents. Due to the highly antimicrobial properties of the metal/metal oxide materials, they can be used for wound dressing applications.

Water sorption and diffusion in cellulose acetate: The effect of plasticisers

The conservation of cellulose acetate plastics in museum collections presents a significant challenge, due to the material's instability. Several studies have led to an understanding of the role of relative humidity (RH) and temperature in the decay process. It is well established that a major decay mechanism in cellulose acetate museum objects is the loss of plasticiser, and that the main decay mechanism of the polymer chain involves hydrolysis reactions. This leads to the loss of sidechain groups and the breakdown of the main polymer backbone. However, interactions between these decay mechanisms, specifically the way in which the loss of plasticiser can modify the interaction between cellulose acetate and water, has not yet been investigated. This research addresses the role of RH, studying the sorption and diffusion of water in cellulose acetate and how this interaction can be affected by plasticiser concentration using Dynamic Vapour Sorption (DVS).

CeO2 Nanoparticle-Containing Polymers for Biomedical Applications: A Review

The development of advanced composite biomaterials combining the versatility and biodegradability of polymers and the unique characteristics of metal oxide nanoparticles unveils new horizons in emerging biomedical applications, including tissue regeneration, drug delivery and gene therapy, theranostics and medical imaging. Nanocrystalline cerium(IV) oxide, or nanoceria, stands out from a crowd of other metal oxides as being a truly unique material, showing great potential in biomedicine due to its low systemic toxicity and numerous beneficial effects on living systems. The combination of nanoceria with new generations of biomedical polymers, such as PolyHEMA (poly(2-hydroxyethyl methacrylate)-based hydrogels, electrospun nanofibrous polycaprolactone or natural-based chitosan or cellulose, helps to expand the prospective area of applications by facilitating their bioavailability and averting potential negative effects. This review describes recent advances in biomedical polymeric material practices, highlights up-to-the-minute cerium oxide nanoparticle applications, as well as polymer-nanoceria composites, and aims to address the question: how can nanoceria enhance the biomedical potential of modern polymeric materials?

Understanding the Barrier and Mechanical Behavior of Different Nanofillers in Chitosan Films for Food Packaging

The continuous petroleum-based plastics manufacturing generates disposal issues, spreading the problem of plastic pollution and its rise in the environment. Recently, innovative techniques and scientific research promoted biopolymers as the primary alternative for traditional plastics, raising and expanding global bioplastic production. Due to its unmatched biological and functional attributes, chitosan (Ch) has been substantially explored and employed as a biopolymeric matrix. Nevertheless, the hydrophilicity and the weak mechanical properties associated with this biopolymer represent a significant intrinsic restriction to its implementation into some commercial applications, namely, in food packaging industries. Distinct methodologies have been utilized to upgrade the mechanical and barrier properties of Ch, such as using organic or inorganic nanofillers, crosslinkers, or blends with other polymers. This review intends to analyze the most recent works that combine the action of different nanoparticle types with Ch films to reinforce their mechanical and barrier properties.

Preparation and characterization of antibacterial nano cerium oxide/chitosan/hydroxyethylcellulose/polyethylene glycol composite films

Due to the rapidly increasing biological applications and antibacterial properties of versatile nano cerium oxide particles, the effects of these particles on chitosan-based films were investigated. Chitosan-based composite films with and without cerium oxide nanoparticles (NPs) were prepared by a casting method. Hydroxyethylcellulose (HEC) was used for the flexibility of films, and polyethylene glycol (PEG) was used as a plasticizer in the blending stage of film preparation. Characterizations of films were done by Fourier transform infrared spectroscopy (FTIR), thermogravimetric analyzer (TGA), and dynamic mechanical analyzer (DMA). Cerium oxide nanoparticle incorporation enhanced the antibacterial activity of chitosan-based films against Escherichia coli and Staphylococcus aureus. This composite film is proposed as packaging or coating material because of its flexibility, antibacterial efficacy, and good mechanical strength.