Polyacrylic acid/ polyvinylpyrrolidone hydrogel wound dressing containing zinc oxide nanoparticles promote wound healing in a rat model of excision injury

Core-shell nanofiber dressings with zinc oxide nanoparticles and cell-free fat extract: boosting fibroblast activity and antibacterial efficacy

BACKGROUND

This study presents the development and characterization of innovative core-shell nanofiber wound dressings incorporating zinc oxide nanoparticles (nZnO) and cell-free fat extract (CEFFE) to enhance fibroblast activity and antibacterial efficacy.

RESULTS

CEFFE was prepared and analyzed, revealing high concentrations of essential growth factors, particularly bFGF and TGF-β1, supporting its therapeutic potential in tissue regeneration. The fabricated nanofibers (PLCL, nZnO/PLCL, PLCL-CEFFE/HA, and nZnO/PLCL-CEFFE/HA) were examined using FE-SEM and TEM, demonstrating successful encapsulation and morphological variations due to nZnO incorporation. XRD analysis confirmed the structural integrity and effective loading of nZnO and CEFFE. Hydrophilicity assessment via water contact angle measurements showed that CEFFE/HA significantly enhanced the hydrophilicity of PLCL membranes, crucial for wound exudate management. Mechanical tests indicated that CEFFE/HA addition maintained the scaffold's mechanical robustness, while nZnO slightly reduced mechanical properties. In vitro release studies revealed a biphasic release pattern of Zn²⁺ ions and growth factors from nZnO/PLCL-CEFFE/HA nanofibers, ensuring prolonged antibacterial activity and sustained therapeutic effects. Antibacterial assays demonstrated significant efficacy against E. coli and S. aureus, attributed to nZnO. MTT assays and FE-SEM analysis confirmed enhanced NIH-3T3 cell proliferation and adhesion on PLCL-CEFFE/HA nanofibers due to the controlled release of growth factors. The scratch assay showed superior cell migration and wound healing potential for PLCL-CEFFE/HA formulations.

CONCLUSIONS

These findings underscore the potential of nZnO/PLCL-CEFFE/HA core-shell nanofibers as multifunctional wound dressings, combining antibacterial properties with enhanced tissue regeneration capabilities. However, further studies are needed to assess long-term stability and in vivo performance, which represent key challenges for future research.

Gallic Acid Nanocrystal Hydrogel: A Novel Strategy for Promoting Wound Healing and Inhibiting Scar Formation

Background

Slow healing of skin wounds is a major health problem affecting millions of people each year, and traditional dressings have limited effectiveness in treating them. Gallic acid has anti-inflammatory, antibacterial and antioxidant properties, and combined with nanotechnology can improve its solubility and provide new directions for wound treatment.

Methods

In this study, Gallic acid nanocrystals (GC-NCs) were prepared by a "top-down" method, and GC-NCs were combined with a polyacrylic acid matrix to form Gallic acid nanocrystal hydrogel (GC-NCs-Gel) by co-gelation. The micromorphology, mechanical properties, adhesion properties and bioactivity of GC-NCs-Gel were tested. Finally, the ability of GC-NCs-Gel to promote wound healing and inhibit scar formation was evaluated in a rat whole skin defect model.

Results

The average particle size of GC-NCs was 348.20 ± 1.42 nm, and GC-NCs-Gel had a honeycomb porous structure with excellent swelling properties (963%), water vapor transmission rate (2400 g/m2/h), tensile stress (28,000 Pa), and adhesive strength (9.6 kPa). GC-NCs-Gel also demonstrated a sustained and controlled drug release property after 48 h of release, the cumulative release was about 57%, and GC-NCs-Gel reached the highest cumulative permeability of 127.2 µg/cm2 within 6 h. In vitro experiments showed that the inhibition circle diameter of GC-NCs-Gel was 39.75 ± 0.61 mm for S. aureus and 21.52 ± 0.06 mm for E. coli. The free radical scavenging efficiency of GC-NCs-Gel reached 77.7% in the DPPH assay and up to 98.6% in ABTS. In vivo experiments showed that GC-NCs-Gel accelerated wound healing by promoting neovascularization, epidermal regeneration and collagen deposition.

Conclusion

In this study, a GC-NCs-Gel with anti-inflammatory, antibacterial as well as antioxidant and wound tissue adhesion was prepared. This multi-functional hydrogel has significant advantages in wound healing, and is expected to provide a new and effective means of wound treatment in the clinic.

Cellulose nanofibers/polyacrylic acid hydrogels integrated with a 3D printed strip: A platform for screening prostate cancer via sarcosine detection

Cellulose nanofiber/polyacrylic acid (CNF/PAA) hydrogel-based colorimetric sensor was fabricated for non-invasive screening of prostate cancer (PCa) via selective detection of sarcosine. The hydrogel was synthesized by photo-crosslinking of acrylic acid in the presence of CNF which acted as mechanical reinforcement and as color enhancer. The hydrogel exhibited a high aqueous absorption and high mechanical strength. A homogeneous distribution of CNF in the hydrogel was confirmed by TEM. A significant improvement in the compressive modulus and stress in the hydrogel were obtained after the incorporation of 0.25%wt CNF. The hydrogel sensor was integrated within a 3D printing strip on a diaper, and it offered a vivid color change from light yellow to blue for detecting sarcosine for PCa indication with a detection limit starting from 10 μM. The colorimetric results were semi-quantitatively evaluated by a spectrophotometer offering a linear range of 0-100 μM with R2 of 0.9901. Furthermore, the increase in CNF content significantly enhanced the sensor's sensitivity toward sarcosine. This sensor could open new avenues for non-invasive screening of prostate cancer in the future.

Advancements in Wound Dressing Materials: Highlighting Recent Progress in Hydrogels, Foams, and Antimicrobial Dressings

Recent advancements in wound dressing materials have significantly improved acute and chronic wound management by addressing challenges such as infection control, moisture balance, and enhanced healing. Important progress has been made, especially with hydrogels, foams, and antimicrobial materials for creating optimized dressings. Hydrogels are known for maintaining optimal moisture levels, while foam dressings are excellent exudate absorbents. Meanwhile, antimicrobial dressing incorporates various antimicrobial agents to reduce infection risks. These dressing options reduce wound healing time while focusing on customized patient needs. Therefore, this review highlights the newest research materials and prototypes for wound healing applications, emphasizing their particular benefits and clinical importance. Innovations such as stimuli-responsive hydrogels and hybrid bioengineered composites are discussed in relation to their enhanced properties, including responsiveness to pH, temperature, glucose, or enzymes and drug delivery precision. Moreover, ongoing clinical trials have been included, demonstrating the potential of emerging solutions to be soon translated from the laboratory to clinical settings. By discussing interdisciplinary approaches that integrate advanced materials, nanotechnology, and biological insights, this work provides a contemporary framework for patient-centric, efficient wound care strategies.

Rat model evaluation for healing-promoting effectiveness and antimicrobial activity of electron beam synthesized (polyvinyl alcohol-pectin)- silver doped zinc oxide hydrogel dressings enriched with lavender oil

Ag/ZnO NPs and lavender oil (LVO) were incorporated into (polyvinyl alcohol/pectin) (PVA/Pet) dressings using electron beam irradiation technology. The Ag/ZnO NPs were prepared using the precipitation method and characterized using XRD, FTIR, and EDX techniques. TEM micrograph shows their spherical appearance with an average size of around 27.4 nm. The increase in the (PVA: Pet) feed solution concentration up to 30% enhances the gel content to 92%. The swelling degree reaches 1674% using 80 wt% pectin content. Meanwhile, increasing the irradiation dose up to 45 kGy increases the gel fraction and negatively affects the swelling capabilities. Incorporating Ag/ZnO NPs and LVO slightly decreased the gel fraction, the swelling degree, and the dressing's porosity reached 87%. In pseudo extracellular fluids, dressings with 10% LVO demonstrate 419% swelling capacities, and their WVTR reaches 271.1 g/m2h. Dressings show biocompatibility, antimicrobial potential, and excellent wound healing capacity towards the excisional wound model in rats, as confirmed by the histological and biochemical results. LVO-(PVA/Pet)-Ag/ZnO dressings may accelerate tissue granulation and remodeling by replacing lost collagen and cause the wound to constrict by upregulating markers associated with wound healing so that it can be recommended as a wound healing candidate.

Janus Films Wound Dressing Comprising Electrospun Gelatin/PCL Nanofibers and Gelatin/Honey/Curcumin Thawed Layer

A promising approach for wound treatment is using multilayer wound dressings that offer multifunctional properties. In this study, a bilayered electrospun/hydrogel gelatin-based scaffold integrated with honey and curcumin was developed to treat wounds under an in vivo study. The first layer consisted of an enzymatic cross-linked gelatin hydrogel containing honey and curcumin, which gelatin/PCL nanofibers reinforced. The physicochemical, mechanical, and biological properties of both layers were evaluated. Then, the bilayered wound dressing was compared to a commercial wound dressing in an in vivo study. The results showed that this strategy provided the wound dressing with a strength of 40 MPa, 70% elongation, 800% swelling rate, and 8 g/h/m2 water vapor permeability. Furthermore, MTT and histopathological staining demonstrated that the bilayered wound dressing promoted wound closure accelerated collagen production and tissue granulation, and promoted immune system response and re-epithelialization compared to other groups. The presence of a nanofibrous layer on the surface of the wound dressing facilitated its use, and the inclusion of honey and gelatin in the hydrogel layer prevented adhesion to the wound tissue and allowed for easy replacement without damaging the wound bed. Overall, the bilayered dressing with multifunctional properties holds great potential for developing wound dressings.

Alleviative effects of green-fabricated zinc oxide nanoparticles on acrylamide-induced oxidative and inflammatory reactions in the rat stomach via modulating gastric neuroactive substances and the MiR-27a-5p/ROS/NF-κB axis

Little is known about the effects of acrylamide (AMD) on the stomach. So, this study evaluated the effect of oral AMD exposure (20 mg/kg b.wt) on oxidative status, apoptotic, and inflammatory reactions in rat's stomach for 60 days. To explore novel targets of AMD toxicity, a more detailed molecular and immune-expression study was performed. Besides, the possible protective effect of green synthesized zinc oxide nanoparticles (G-ZNP) (10 mg/kg b.wt) was explored. The results revealed that AMD significantly provoked oxidative and lipid peroxidative damage of the stomach in terms of increased ROS and MDA but reduced SOD, CAT, GSH, and GSH/GSSG. Additionally, the stomachs of AMD-exposed rats showed a significant increment of PGE2 but reduced NO. Histopathologically, AMD induced a significant increase in PAS stain and the immunoexpression of iNOS and NF-κB in the glandular stomach. A significant upregulation of CART, VACHT, EGFR, caspase-3, NOS-1, and miR-27a-5p was evident in the stomach of the AMD group. Yet, G-ZNP oral dosing significantly rescued the AMD-induced oxidative damage, apoptotic reaction, inflammatory effect, and altered miR-27a-5p and gene expressions in the stomach. Conclusively, these findings demonstrated the efficacy of G-ZNP in protecting against the harmful impacts of acrylamide on stomach tissues.

New Composite Materials Based on PVA, PVP, CS, and PDA

In this work, new materials based on the blends of polyvinyl alcohol (PVA), polyvinyl pyrrolidone (PVP), chitosan (CS), and polydopamine (PDA) have been prepared. Fourier Transform Infrared Spectra have been conducted to verify the presence of individual components in the composite materials. EDX elemental analysis showed a clear view of the element's presence in the composite materials, with the maximum values for carbon and oxygen. Atomic force microscopy (AFM) was used to observe the surface topography and measure the surface roughness. In the case of the individual polymers, CS presented the higher value of surface roughness (Rq = 3.92 nm and Ra = 3.02 nm), and surface roughness was found to be the lowest in the case of polyvinyl pyrrolidone (PVP), and it was with values (Rq = 2.34 nm and Ra = 0.95 nm). PVA films presented the surface roughness, which was with the value (Rq = 3.38 nm and Ra = 2.11 nm). In the case of composites, surface roughness was highest for the composite based on PVA, PVP, and CS, which presented the value (Rq = 11.91 nm and Ra = 8.71 nm). After the addition of polydopamine to the polymeric composite of PVA, PVP, and CS, a reduction in the surface roughness was observed (Rq = 7.49 nm and Ra = 5.15 nm). The surface roughness for composite materials was higher than that of the individual polymers. The addition of PDA to polymeric composite (PVA/PVP/CS) led to a decrease in Young's modulus. The elongation percentage of the polymeric films based on the PVA/PVP/CS/PDA blend was higher than that of the blend without PDA (9.80% vs. 5.68% for the polymeric composite PVA/PVP/CS). The surface of polymeric films was hydrophilic. The results from the MTT assay showed that all tested specimens are non-toxic, and it was manifested by a significant increase in the viability of L929 cells compared with control cells. However, additional studies are required to check the biocompatibility of tested samples.

Puerarin: a hepatoprotective drug from bench to bedside

Pueraria is a time-honored food and medicinal plant, which is widely used in China. Puerarin, the main component extracted from pueraria, has a variety of pharmacological characteristics. In recent years, puerarin has received increasing attention for its significant hepatoprotective effects, such as metabolic dysfunction-associated steatotic liver disease, alcohol-related liver disease, and hepatic carcinoma. This paper explores the pharmacological effects of puerarin on various liver diseases through multiple mechanisms, including inflammation factors, oxidative stress, lipid metabolism, apoptosis, and autophagy. Due to its restricted solubility, pharmacokinetic studies revealed that puerarin has a low bioavailability. However, combining puerarin with novel drug delivery systems can improve its bioavailability. Meanwhile, puerarin has very low toxicity and high safety, providing a solid foundation for its further. In addition, this paper discusses puerarin's clinical trials, highlighting its unique advantages. Given its excellent pharmacological effects, puerarin is expected to be a potential drug for the treatment of various liver diseases.

Fabrication of fiber-particle structures by electrospinning/electrospray combination as an intrinsic antioxidant and oxygen-releasing wound dressing

In this study, we employed a combination of electrospinning and electrospray techniques to fabricate wound dressings with a particle-fiber structure, providing dual characteristics of oxygen-releasing and intrinsic antioxidant properties, simultaneously. The electrospun part of the dressing was prepared from a blend of polycaprolactone/gallic acid-grafted-gelatin (GA-g-GE), enabling intrinsic ROS scavenging. To the best of our knowledge, this is the first time that PCL/GA-g-GE was fabricated by electrospinning. Furthermore, polyvinyl pyrrolidone (PVP) microparticles, containing calcium peroxide nanoparticles (CNPs), were considered as the oxygen production agent through the electrospray part. The CNP content was 1% and 3% w/w of PVP while biopolymer:PCL was 10% w/w. The fabricated structures were characterized in terms of fiber/particle morphology, elemental analysis, oxygen release behavior, ROS inhibition capacity, and water contact angle assessments. The covalent bonding of gallic acid to gelatin was confirmed by 1H-NMR, UV spectroscopy, and FTIR. According to the SEM results, the morphology of the prepared PCL/biopolymer fibers was bead-free and with a uniform average diameter. The analysis of released oxygen showed that by increasing the weight percentage of CNPs from 1 to 3 wt%, the amount of released oxygen increased from 120 mmHg to 195 mmHg in 24 h, which remained almost constant until 72 h. The obtained DPPH assay results revealed that the introduction of GA-g-GE into the fibrous structure could significantly improve the antioxidant properties of wound dressing compared to the control group without CNPs and modified gelatine. In vitro, the fabricated wound dressings were evaluated in terms of biocompatibility and the potential of the dressing to protect human dermal fibroblasts under oxidative stress and hypoxia conditions by an MTT assay. The presence of GA-g-GE led to remarkable protection of the cells against oxidative stress and hypoxia conditions. In vivo studies revealed that the incorporation of intrinsic ROS inhibition and oxygen-releasing properties could significantly accelerate the wound closure rate during the experimental period (7, 14, and 21 days). Additionally, histopathological investigations in terms of H&E and Masson's trichrome staining showed that the incorporation of the two mentioned capabilities remarkably facilitated the wound-healing process.

Bringing innovative wound care polymer materials to the market: Challenges, developments, and new trends

The development of innovative products for treating acute and chronic wounds has become a significant topic in healthcare, resulting in numerous products and innovations over time. The growing number of patients with comorbidities and chronic diseases, which may significantly alter, delay, or inhibit normal wound healing, has introduced considerable new challenges into the wound management scenario. Researchers in academia have quickly identified promising solutions, and many advanced wound healing materials have recently been designed; however, their successful translation to the market remains highly complex and unlikely without the contribution of industry experts. This review article condenses the main aspects of wound healing applications that will serve as a practical guide for researchers working in academia and industry devoted to designing, evaluating, validating, and translating polymer wound care materials to the market. The article highlights the current challenges in wound management, describes the state-of-the-art products already on the market and trending polymer materials, describes the regulation pathways for approval, discusses current wound healing models, and offers a perspective on new technologies that could soon reach consumers. We envision that this comprehensive review will significantly contribute to highlighting the importance of networking and exchanges between academia and healthcare companies. Only through the joint of these two actors, where innovation, manufacturing, regulatory insights, and financial resources act in harmony, can wound care products be developed efficiently to reach patients quickly and affordably.

Design and Self-Assembly of Peptide-Copolymer Conjugates into Nanoparticle Hydrogel for Wound Healing in Diabetes

Background

Delayed wound healing in skin injuries has become a significant problem in clinics, seriously affecting and even threatening life and health. Recently, research interest has increased in developing wound dressings containing bioactive compounds capable of improving outcomes for complex healing needs.

Methods

In this study, Puerarin-loaded nanoparticles (Pue-NPs) were prepared using the cell-penetrating peptide-poly (lactic-co-glycolic acid) (CPP-PLGA) as a drug carrier by the emulsified solvent evaporation method. Then, they were added into poly (acrylic acid) to obtain a self-assembled nanocomposite hydrogels (SANHs) drug delivery system using the co-polymerization method. The particle size, zeta potential, and micromorphology of Pue-NPs were measured; the appearance, mechanical properties, adhesive strength, and biological activity of SANHs were performed. Finally, the potential of SANHs for wound healing was further evaluated in streptozotocin-induced diabetic mice.

Results

Pue-NPs were regularly spherical, with an average particle size of 134.57 ± 1.42 nm and a zeta potential of 2.14 ± 0.78 mV. SANHs was colorless and transparent with a honeycomb-like porous structure and had an excellent swelling ratio (917%), water vapor transmission rate (3077 g·m-2·day-1), mechanical properties (Young's modulus of 18 kPa, elongation at break of 307%), and adhesive strength (15.5 kPa). SANHs exhibited sustained release of Pue over 48h, with a cumulative release of 55.60 ± 6.01%. In vitro tests revealed that the SANHs presented a 92.22% antibacterial rate against Escherichia coli after 4h, and a 61.91% scavenging rate of 1.1-diphenyl-2-trinitrophenylhydrazine (DPPH) radical. In vivo experiments showed that SANHs accelerated wound repair by reducing the inflammatory response at the wound site, promoting angiogenesis, and facilitating epidermal regeneration and collagen deposition.

Conclusion

In conclusion, we successfully prepared SANHs. Our results show that SANHs have excellent performance and improves wound healing in diabetic mice model, indicating that it can be used to develop an effective strategy for the treatment of diabetic wounds.

Pyolytics as a product of the physical–chemical repurposing of antiseptics and an alternative to larval therapy for chronic wounds

The traditional treatment of chronic wounds involves daily cleansing of the wound surface from purulent necrotic masses using mechanical and medicinal methods, accompanied by regular replacement of wound dressing. In this case, medicinal wound cleansing lasts 10–15 mins from the time of replacement of the old wound dressing with the new one. According to established practice, medicinal sanitation of infected and purulent wounds during dressing involves irrigation of the wound surface with cleansing solutions, antiseptics, and/or antibiotics. In severe cases, the above therapy is supplemented with live larvae of the necrophage fly, which are injected into purulent necrotic masses and left in them under wound dressing until wounds are completely cleansed from pus. Nevertheless, the generally accepted course of treatment of chronic wounds remains ineffective. The use of pyolytics and their supplementation with wound dressings in the form of warm wet compresses, which create a local greenhouse effect in wounds, was reported to accelerate the healing of chronic wounds. Pyolytics are a group of antiseptics developed in Russia. They are warm alkaline solutions of hydrogen peroxide; when they interact with purulent necrotic masses, these solutions dissolve very quickly and foam them. Because of the interaction with pyolytics, thick purulent masses immediately turn into fluffy oxygenated foam. Pyolytics have been developed because of the physicochemical repurposing of aqueous solutions of sodium hydrogen carbonate and hydrogen peroxide. To accelerate the healing of chronic wounds, a recommendation was to irrigate the surface of chronic wounds with 3% hydrogen peroxide and 2–10% sodium bicarbonate solutions, heated to 37–45°C, which have alkaline activity at pH 8.4–8.5 and are enriched with dissolved carbon dioxide or oxygen (due to excess pressure of 0.2 atm). This study presented the importance of treating chronic wounds using politics and treatment outcomes using pyolytics along with warm moist dressing compresses, demonstrating a wound-healing effect. Consequently, physical and chemical reprofiling of antiseptics may make them effective pyolytics, and the combination of pyolytics with warm wound dressings such as warm moist compresses, which create a local greenhouse effect on wounds, accelerates the healing of chronic wounds.

Hydrogels and Wound Healing: Current and Future Prospects

The care and rehabilitation of acute and chronic wounds have a significant social and economic impact on patients and global health. This burden is primarily due to the adverse effects of infections, prolonged recovery, and the associated treatment costs. Chronic wounds can be treated with a variety of approaches, which include surgery, negative pressure wound therapy, wound dressings, and hyperbaric oxygen therapy. However, each of these strategies has an array of limitations. The existing dry wound dressings lack functionality in promoting wound healing and exacerbating pain by adhering to the wound. Hydrogels, which are commonly polymer-based and swell in water, have been proposed as potential remedies due to their ability to provide a moist environment that facilitates wound healing. Their unique composition enables them to absorb wound exudates, exhibit shape adaptability, and be modified to incorporate active compounds such as growth factors and antibacterial compounds. This review provides an updated discussion of the leading natural and synthetic hydrogels utilized in wound healing, details the latest advancements in hydrogel technology, and explores alternate approaches in this field. Search engines Scopus, PubMed, Science Direct, and Web of Science were utilized to review the advances in hydrogel applications over the last fifteen years.