Bioactive anti-oxidative polycaprolactone/gelatin electrospun nanofibers containing selenium nanoparticles/vitamin E for wound dressing applications

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

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

Recent advances in reactive oxygen species scavenging nanomaterials for wound healing

Reactive oxygen species play a crucial role in cell signaling pathways during wound healing phases. Treatment strategies to balance the redox level in the deep wound tissue are emerging for wound management. In recent years, reactive oxygen species scavenging agents including natural antioxidants, reactive oxygen species (ROS) scavenging nanozymes, and antioxidant delivery systems have been widely employed to inhibit oxidative stress and promote skin regeneration. Here, the importance of reactive oxygen species in different wound healing phases is critically analyzed. Various cutting-edge bioactive ROS nanoscavengers and antioxidant delivery platforms are discussed. This review also highlights the future directions for wound therapies via reactive oxygen species scavenging. This comprehensive review offers a map of the research on ROS scavengers with redox balancing mechanisms of action in the wound healing process, which benefits development and clinical applications of next-generation ROS scavenging-based nanomaterials in skin regeneration.

Synthesis of homogeneous spherical selenium nanoparticles through a chemical method for cancer therapy applications

Oxidative stress is associated with pathologies affecting various organs or metabolic pathways. Thus, targeting oxidative stress might represent a valid therapeutic option. Selenium nanoparticles (SeNPs) are reported to exert antioxidant effects by many mechanisms. Our purpose was to assess in vitro on normal (MRC-5) and cancer (PANC-1) cell lines the potential of SeNPs for inducing cytotoxicity and redox modulation. They were synthesized through a chemogenic method and characterized through advanced microscopy techniques. SeNPs were spherical, with 100 nm average diameters and low dimension variability. Cancer and normal cells were exposed for 24 h to different concentrations of SeNPs ranging from 1 to 25 μg/mL. According to the LDH and MTT assay results, SeNPs treatment caused a more pronounced decrease in cancer cell viability compared to normal cells, suggesting a possible therapeutic benefit on tumors, thus supporting the hypothesis of therapeutic use of SeNPs with the benefit of cell type selectivity. Neither an elevation nor an inhibition of intracellular ROS production was detected in MRC-5 cells exposed to concentrations between 1 and 25 μg/mL SeNPs. The results of this study suggest that SeNPs could represent potential candidate for treatment of cancer, especially pancreatic adenocarcinoma.

Electrospun zein nanofibers loaded with curcumin as a wound dressing: enhancing properties with PSS and PDADMAC layers

Development of wound dressings with enhanced therapeutic properties is of great interest in the modern healthcare. In this study, a zein-based nanofibrous wound dressing containing curcumin as a therapeutic agent was fabricated through electrospinning technique. In order to achieve desirable properties, such as antibacterial characteristics, reduced contact angle, and enhanced mechanical properties, the layer-by-layer technique was used for coating the surfaces of drug-loaded nanofibers by sequentially incorporating poly (sodium 4-styrene sulfonate) as a polyanion and poly (diallyldimethylammonium chloride) (PDADMAC) as a polycation. Various analyses, including scanning electron microscopy, Fourier transform infrared spectroscopy, drug release assessment., and mechanical tests were employed to assess the characteristics of the prepared wound dressings. Based on the results, coating with polyelectrolytes enhanced the Young's modulus and tensile strength of the electrospun mat from 1.34 MPa and 4.21 MPa to 1.88 MPa and 8.83 MPa, respectively. The coating also improved the controlled release of curcumin and antioxidant activity, while the outer layer, PDADMAC, exhibited antibacterial properties. The cell viability tests proved the appropriate biocompatibility of the prepared wound dressings. Moreover, our findings show that incorporation of the coating layers enhances cell migration and provides a favorable surface for cell attachment. According to the findings of this study, the fabricated nanofibrous wound dressing can be considered a promising and effective therapeutic intervention for wound management, facilitating the healing process.

Biobran-loaded core/shell nanofibrous scaffold: a promising wound dressing candidate

This research examined the effectiveness of Biobran as a bioactive substance that could potentially improve wound healing. It also looked at how Biobran affects the properties of a nanofibrous scaffold made through coaxial electrospinning. This is the first study exploring the use of Biobran in this context and its interaction with nanofibrous scaffolds. The scaffolds were composed of poly(ε-caprolactone) (PCL) in the shell and various concentrations of Biobran blended with polyvinyl alcohol (PVA) in the core. The properties of the scaffolds were characterized by SEM, TEM, FTIR, XRD, TGA, DSC, stress-strain test, WCA, release test, MTT cytotoxicity assay, wound scratching assay, and the dye exclusion method using trypan blue. The scaffolds loaded with Biobran exhibited a more compact and smooth morphology compared with the scaffold without Biobran. The physical interaction and crystallinity of the polymers in the scaffolds were also affected by Biobran in a concentration-dependent manner. This positively influenced their tensile strength, elongation at break, thermal stability, and hydrophilicity. The porosity, water uptake capacity, and WVTR of the nanofibrous scaffolds are within the optimal ranges for wound healing. The release rate of Biobran, which revealed a biphasic release pattern, decreased with increasing Biobran concentration, resulting in controlled and sustained delivery of Biobran from the nanofiber scaffolds. The cell viability assays showed a dose-dependent effect of Biobran on WISH cells, which might be attributed to the positive effect of Biobran on the physicochemical properties of the nanofibrous scaffolds. These findings suggest that Biobran-loaded core/shell nanofiber scaffolds have a potential application in wound healing as an ideal multifunctional wound dressing.

Selenium nanoparticles incorporated in nanofibers media eliminate H1N1 activity: a novel approach for virucidal antiviral and antibacterial respiratory mask

The consecutive viral infectious outbreaks impose severe complications on public health besides the economic burden which led to great interest in antiviral personal protective equipment (PPE). Nanofiber-based respiratory mask has been introduced as a significant barrier to eliminate the airborne transmission from aerosols toward reduction the viral infection spreading. Herein, selenium nanoparticles incorporated in polyamide 6 nanofibers coated on spunbond nonwoven were synthesized via electrospinning technique (PA6@SeNPs), with an average diameter of 180 ± 2 nm. The nanofiber-coated media were tested for 0.3 μm particulate filtration efficiency based on Standard NIOSH (42 CFR 84). PA6@SeNPs had a pressure drop of 45 ± 2 Pa and particulate filtration efficiency of more than 97.33 which is comparable to the N95 respiratory mask. The bacterial killing efficiency of these nanofibers was 91.25% and 16.67% against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli), respectively. Furthermore, the virucidal antiviral test for H1N1 infected Madin-Darby Canine Kidney cells (MDCK) exhibited TCID50 of 108.13, 105.88, and 105.5 for 2, 10, and 120 min of exposure times in comparison with 108.5, 107.5, and 106.5 in PA6 nanofibers as control sample. MTT assay indicated excellent biocompatibility of electrospun PA6@SeNP nanofibers on L292 cells. These results propose the PA6@SeNP nanofibers have a high potential to be used as an efficient layer in respiratory masks for protection against respiratory pathogens.

Fabrication and evaluation of vitamin doped Zno/AgNPs nanocomposite based wheat gluten films: a promising findings for burn wound treatment

Burn wound treatment remains a significant issue in wound care management especially when multidrug resistant bacterial infection and accumulation are present. Delayed wound healing is mostly due to ineffectiveness of commercially available wound dressings that protects the wound but less efficient in healing perspective. Therefore, nano-based wound dressing might be efficient solution for wound healing management. The present study reports the fabrication and evaluation of zinc oxide (ZnO) or silver nanoparticles (Ag NPs) capped with vitamin A or E nanocomposite that were incorporated in wheat gluten (WG) films. The chemical structure, phase purity, and morphological features confirmed the successful coating of NPs by vitamins A and E and their interaction with WG during film casting. The maximum swelling response was observed by NPs vitamin composite WG films than control films while slow release of vitamins and NPs from films was observed up to 24 h. WG films either carrying ZnO or Ag NPs, and vitamin A or E demonstrated significant antioxidant and antibacterial potential. The NPs-vitamin composite loaded WG films showed wound contraction within 14 days during in vivo burn wound healing experiments on mice model. The rates of wound healing, re-epithelialization, collagen deposition with fibroblast regeneration, adipocytes, and hair follicle development were observed through visual and histopathological examination. The study reveals that vitamin A or E doped ZnO or Ag NPs fabricated in WG can be efficiently used against burn wounds due to their physiochemical and biological properties. Furthermore the biocompatible nature and biodegradable potential make the films more prone to mankind maneuver for initial protection and healing remedy.

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.

Nanoparticles incorporated in nanofibers using electrospinning: A novel nano-in-nano delivery system

Nanofibers are cutting-edge drug delivery systems that are being utilised to treat a variety of ailments. Nanofibers are mostly woven by electrospinning techniques that are majorly used in drug delivery, wound dressing, tissue engineering, sensors, etc. They have several limitations that can be addressed by developing nano-in-nano delivery techniques. Nanoparticles are incorporated into nanofibers in these nano-in-nano systems. They offer a lot of benefits over other nanosystems, including the ability to shield drugs from physical deterioration, the ability to provide prolonged drug release, high surface area to volume ratio, increased drug loading capacity and the potential to be employed in critical conditions such as cancer. These nanoparticles can be encapsulated, entrapped, or adsorbed onto nanofibers in a variety of ways. To include nanosystems into nanofibers, a variety of materials and different kinds of nanoparticles can be used. The present review gives an insight to the applications of nano - in - nano drug delivery system for different diseases/disorders. The review also brings forward the current state of these novel delivery systems along with future perspectives.

Pullulan hydrogel-immobilized bacterial cellulose membranes with dual-release of vitamin C and E for wound dressing applications

Vitamin C&E (VtC&VtE)-loaded bilayer wound dressings were prepared using bacterial cellulose (BC) synthesized by Acetobacter species and pullulan (PUL). VtC-containing PUL hydrogels (100 μg/mL) were immobilized onto BC by crosslinking. BC/PUL-VtC was loaded with VtE (100 μM in ethanol) by immersion for 2 h. No delamination between the layers was observed via SEM. Despite the porous inner PUL side, the outer BC side exhibited nanofibrous morphology serving as barriers to prevent microorganism invasion. Equilibrium water content of BC/PUL was above 85 % due to the hydrogel characteristics of PUL side, suitable to absorb exudate in wound bed. PUL layer lost >90 % of its weight in simulated wound fluid and > 99 % in lysozyme solution within 14 days, mediating co-release of VtC&VtE. Thin BC side possessed adequate strength (⁓22 MPa) and strain (>30 %) to endure against tensile stress generated by bending on wound surface without rupture, whereas thick PUL side was flexible (>70 % strain) to fit into wound bed under compressive stress without causing harm. In vitro studies using L929 fibroblasts elucidated PUL side was anti-adhesive and removable. Synergistic effect of VtC&VtE on antioxidant activity, wound closure, and collagen synthesis was observed. Thus, BC/PUL-VtC/VtE hold promise as cheap and eco-friendly temporary wound dressing.

Progress in Gelatin as Biomaterial for Tissue Engineering

Tissue engineering has become a medical alternative in this society with an ever-increasing lifespan. Advances in the areas of technology and biomaterials have facilitated the use of engineered constructs for medical issues. This review discusses on-going concerns and the latest developments in a widely employed biomaterial in the field of tissue engineering: gelatin. Emerging techniques including 3D bioprinting and gelatin functionalization have demonstrated better mimicking of native tissue by reinforcing gelatin-based systems, among others. This breakthrough facilitates, on the one hand, the manufacturing process when it comes to practicality and cost-effectiveness, which plays a key role in the transition towards clinical application. On the other hand, it can be concluded that gelatin could be considered as one of the promising biomaterials in future trends, in which the focus might be on the detection and diagnosis of diseases rather than treatment.

Adjusting the accuracy of PEGDA-GelMA vascular network by dark pigments via digital light processing printing

Vascularization is one of the most important factors greatly influencing scaffold regeneration. In this study, a precise network of hollow vessels was printed by digital light processing (DLP) with poly(ethylene glycol) diacrylate (PEGDA)/gelatin-methacryloyl (GelMA), and dark pigmentation absorbers were added to ensure printing accuracy. First, the compound bio-inks of the PEGDA-GelMA hydrogel were prepared for direct vascular printing, and a high-precision DLP system was established. Second, the printing effects of three dark absorbers, namely, nigrosin, brilliant black, and brilliant blue, on the x-, y-, and z-axes were studied. By printing models with different densities, it was determined that 0.2% nigrosin, 0.1% brilliant black, and 0.3% brilliant blue had better effects on the x- and y-axes accuracy, and the absorbance of the absorbers played a decisive role in adjusting the accuracy. Additionally, to solve the problem of uneven curing on the upper and lower surfaces caused by the addition of an absorber with high absorbance, a model of the difference in curing width between the upper and lower surfaces of a unit-layer slice based on high-absorbance absorbers was established, and the reference value for the slice thickness was calculated. Third, the biological and mechanical properties of the bio-inks were verified with scanning electron microscopy and Fourier transform infrared, and by tensile, swelling, degradation, and cytotoxicity tests on different concentrations of PEGDA-GelMA hydrogel and absorbers. The results showed that 30% PEGDA-7% GelMA/0.1% brilliant black was the optimal preparation to print a hollow vascular network. The error of the printing tube wall and cavity was between 1% and 3%, which demonstrates the high precision of the method. Human umbilical vein endothelial cells were planted in the lumen, and the survival rate achieved 107% on the seventh day, demonstrating the good biocompatibility of the composite hydrogel.

Elemental Selenium Enriched Nanofiber Production

This study aimed to produce electrospun nanofibers from a polyvinyl butyral polymer (PVB) solution enriched with red and grey selenium nanoparticles. Scanning electron microscopic analysis was used to observe the samples, evaluate the fiber diameters, and reveal eventual artifacts in the nanofibrous structure. Average fiber diameter is determined by manually measuring the diameters of randomly selected fibers on scanning electron microscopic (SEM) images. The obtained nanofibers are amorphous with a diameter of approximately 500 nm, a specific surface area of approx. 8 m² g⁻¹, and 5093 km cm⁻³ length. If the red and grey selenium nanoparticles were produced in powder form and suspended to the ethanolic solution of PVB then they were located inside and outside the fiber. When selenium nanoparticles were synthesized in the PVB solution, then they were located only inside the fiber. These nanofiber sheets enriched with selenium nanoparticles could be a good candidate for high-efficiency filter materials and medical applications.