Bio-functional hydrogel membranes loaded with chitosan nanoparticles for accelerated wound healing

Traditional wound dressings often cannot treat wounds caused by bacterial infections or other wound types that are insensitive to these wound treatments. Therefore, a biodegradable, bioactive hydrogel wound dressing could be an effective alternative option. The purpose of this study was to develop a hydrogel membrane comprised of sodium alginate, polyvinyl alcohol, acrylic acid, and gallic acid for treating skin wounds. The newly developed membranes were analyzed using Fourier transform infrared spectroscopy (FTIR), thermogravimetric analysis (TGA), differential scanning calorimetry (DSC) and scanning electron microscopy (SEM), X-ray diffraction analysis (XRD), sol-gel fraction, porosity, mechanical strength, swelling, drug release and data modelling, polymeric network parameters, biodegradation, and antioxidation (DPPH and ABTS) and antimicrobial activity against Gram-positive and negative bacteria. The results revealed that hydrogel membranes were crosslinked successfully and had excellent thermal stability, high drug loading, greater mechanical strength, and exhibited excellent biodegradation. Additionally, the swelling ability and the porosity of the surface facilitated a controlled release of the encapsulated drug (gallic acid), with 70.34% release observed at pH 1.2, 70.10% at pH 5.5 (normal skin pH), and 86.24% at pH 7.4 (wounds pH) in 48 h. The gallic acid-loaded hydrogel membranes showed a greater area of inhibition against Pseudomonas aeruginosa, Staphylococcus aureus, and Escherichia coli bacteria as well as demonstrated excellent antioxidant properties. Based on Franz cell analyses, the permeation flux of the drug from optimized formulations through mice skin was 92 (pH 5.5) and 110 (pH 7.4) μg/cm2·h-1. Moreover, hydrogel membranes retained significant amounts of drug in the skin for 24 h, such as 2371 (pH 5.5) and 3300 µg/cm2 (pH 7.4). Acute dermal irritation tests in rats showed that hydrogel membranes were nonirritating. Hydrogel membranes containing gallic acid could be an effective option for improving wound healing and could result in faster wound healing.

In this work, hydrogel membranes were developed based on poly vinyl alcohol (PVA), starch (St), and chitosan (Cs) hydrogels with nano Zinc oxide (nZnO). PVA/St/Cs/nZnO hydrogel membranes were prepared by freezing-thawing cycles, and the aqueous PVA/St solutions were prepared by dissolving PVA in distilled water. After the dissolution of PVA, starch was mixed, and the mixture was stirred. Then, chitosan powder was added into acetic acid, and the mixture was stirred to form a chitosan solution. Subsequently, Cs, St and PVA solutions were blended together to form a homogeneous PVA/St/Cs ternary blend solution. Measurement of Equilibrium Swelling Ratio (ESR), Water Vapor Transmission Test (WVTR), mechanical properties, scanning electron microscopy (SEM), MTT [3-(4, 5-dimethylthiazol-2-yl)-2, 5-diphenyl tetrazolium bromide] assay, antibacterial studies, in vivo wound healing effect and histopathology of the hydrogel membranes were then performed. The examination revealed that the hydrogel membranes were more effective as a wound dressing in the early stages of wound healing and that the gel could be used in topic applications requiring a large spectrum of antibacterial activity; namely, as a bandage for wound dressing.

Bioinspired sodium alginate based thermosensitive hydrogel membranes for accelerated wound healing

Synthesis of AgO/CuO/PVA/starch hydrogel by casting method and characterizations to safely overcome skin infections: A possible application in wound healing as a dressing

Material barrier properties to microbes are an important issue in many pharmaceutical applications like wound dressings. A wide range of biomaterials has been used to manage the chronic inflamed wounds. Eight hydrogel membranes of poly vinyl alcohol (PVA) with κ-carrageenan (KC) and Lactobacillus bulgaricus extract (LAB) have been prepared by using freeze-thawing technique. To evaluate the membranes efficiency as wound dressing agents, various tests have been done like gel fraction, swelling behavior, mechanical properties, etc. The antibacterial activities of the prepared membranes were tested against the antibiotic-resistant bacterial isolates. In addition, the safety usage of the prepared hydrogel was checked on human dermal fibroblast cells. The anti-inflammatory properties of the prepared hydrogel on LPS-PBMC cell inflammatory model were quantified using enzyme-linked immunosorbent assay (ELISA) and real-time polymerase chain reaction (RT-qPCR). The analysis data of TGA, SEM, gel fraction, and swelling behavior showed changes in properties of prepared PVA\KC\LAB hydrogel membrane than pure PVA hydrogel membrane. The antibacterial activities of the prepared membranes augmented in LAB extract-prepared membranes. Out of the eight used hydrogel membranes, the PVAKC4 hydrogel membrane is the safest one on fibroblast cellular proliferation with a maximum proliferation percentage 97.3%. Also, all the used hydrogel membrane showed abilities to reduce the concentration of IL-2 and IL-8 compared with both negative and positive control. In addition, almost all the prepared hydrogel membrane showed variable abilities to downregulate the expression of TNF-α gene with superior effect of hydrogel membrane KC1. PVA/KC/LAB extract hydrogel membrane may be a promising material for wound dressing application and could accelerate the healing process of the chronic wound because of its antimicrobial and anti-inflammatory properties.

Infected wounds pose significant challenges in clinical settings due to the risk of complications and delayed healing of wounds. The most common wound dressings are cotton balls and gauze, and yet these traditional wound dressings have inherent shortcomings including low antibacterial properties, less oxygen permeation, mechanical properties, and moisture content essential for wound healing of infected wounds. Herein, we fabricate polyvinyl alcohol/chitosan/pectin (PVA/CH/PEC) hydrogel loaded with green-synthesized nanometals, and synthetic antibiotics for the treatment of infected wounds with enhanced mechanical properties, synergistic antibacterial properties, higher moisture, and oxygen permeation content. The silver nanoparticles (AgNPs), synthesized via sea buckthorn leaf extract, and ciprofloxacin were incorporated in the bio-nanocomposite hydrogels. The particle size of AgNPs was found to be in the range of 15 to 42 nm. The synthesized bio-nanocomposite hydrogels confirm its biocompatible nature because of reduction in the percentage hemolysis from 1.7% to 1.4% and cell viability exceeding 87% in PVA/CH/PEC and poly vinyl alcohol/chitosan/pectin–Silver/ ciprofloxacin (PVA/CH/PEC-Ag/cipro) hydrogel membranes, respectively. Microscopic observation of PVA/CH/PEC/Ag-Ciprofloxacin hydrogels demonstrated the last stages of regeneration and skin reformation towards normal skin as compared to hydrogel scaffold without ciprofloxacin. The hydrogel promoted advanced stages of regeneration and skin reformation, signifying its potential as a promising dressing material for infected wound healing applications.

Wound infection is the primary challenge in the wound care management. To facilitate patients, the health care sector is trying to use the modern technology in the field of wound management. Various cellular processes and biological environments are intertwined in the process of wound repair. The compulsion for the modern dressing is not only to cover the wound but also to facilitate the healing rate of wound. In this research, the hydrogel membranes were prepared by crosslinking poly vinyl alcohol (PVA) with starch by using glutaraldehyde. Turmeric was added as an anti-bacterial agent. 0.5 g of turmeric showed the highest anti-bacterial activity among different turmeric contents used. For physical and mechanical characterization, the hydrogel membrane without turmeric (neat hydrogel) and 0.5 g were selected. FTIR of both hydrogel membranes confirmed the presence of free hydroxyl groups. Moreover, hydrogel membrane containing turmeric resulted stronger hydrogen bond interaction. Mechanical analysis of hydrogel membrane revealed sufficient strength to be used as wound dressing. The SEM images evolved that both hydrogel membranes were dense in nature. The swelling behavior values were greater than 100% for both hydrogel membranes. The water vapor transmission rate for 0.5 g turmeric hydrogel membrane was 52.85 g/m2h.

Poly(vinyl alcohol)PVA is a hydrophilic polymer and water soluble . It is used in many biomedical and pharmaceutical applications, due to its advantages such as: non-toxic, non-carcinogenic, and biodegradable characteristics with the ease of processing. Physically cross-linked hydrogel membranes composed of different amounts of hyaluronic acid (HA) blend with (PVA) were prepared by freeze–thawing method. This freezing–thawing cycle was repeated for three consecutive cycles. Properties of (PVA–HA) hydrogel membrane such as gel fraction, swelling, mechanical properties(tensile strength, elongation to break),degradation and protein adsorption were investigated. With the increasing of HA content, the gel fraction, the maximum tensile strength and elongation at break(%) of (PVA-HA) hydrogel membranes were decreased. Furthermore, with the increase of HA content, the swelling, the protein adsorption and the hydrolytic degradation of PVA-HA hydrogel membrane were increased.After soaking of hydrogel membrane for three days in phosphate buffer saline (PBS), the maximum weight loss of PVA–HA hydrogel membranes ranged between 18% and 70% according to HA content, this indicates that they are biodegradable.

Triethyl orthoformate mediated a novel crosslinking method for the preparation of hydrogels for tissue engineering applications: characterization and in vitro cytocompatibility analysis.

Phytochemical screening of an essential oil-loaded PVA/GA hydrogel membrane for potential wound healing application

Wound healing is a delicate, complex and challenging medical process. Hydrogel is a material that possesses properties aligned with the ideal characteristics required for wound dressings. Its mechanical properties, derived from the interconnection of fibers, closely resemble those of soft tissues regarding moisture retention, secretion absorption, and oxygen permeability. Additionally, hydrogels can be tailored to perform various functions, such as crosslinking with other materials and loading drugs, bioactive compounds and growth factors. This review focuses on the fabrication of multifunctional hydrogel wound dressings using both natural and synthetic biological materials, including silk fibroin, chitosan, alginate, cellulose, hyaluronic acid, polyvinyl alcohol, polyethylene glycol and polyvinyl pyrrolidone, each exhibiting distinct properties that enhance their efficacy as wound dressings. Consequently, this review highlights significant advancements in developing more effective hydrogel wound dressings. HIGHLIGHTS Chronic wounds have a significant impact on patient well-being; thus, the use of hydrogel-based wound dressings can significantly influence the rate and quality of the wound healing process. The design of hydrogel should also reduce inflammation, eliminate infection, promote healing process, and exploit mechanical qualities to absorb exudates. By incorporating bioactive molecules such as growth factors and antibacterial agents into hydrogel scaffolds, wound healing process can be enhanced. Before clinical trials, novel hydrogels require biocompatibility, mechanical, moisture retention, and animal model studies to ensure efficacy and safety. By addressing the research gap and proposing the direction of future wound dressing development, it would improve the patient outcomes for chronic wound treatment. GRAPHICAL ABSTRACT

α-Mangostin encapsulated gellan gum membranes for enhanced antibacterial, anti-inflammatory, antioxidant and wound healing activity.

Bioactive and multifunctional keratin-pullulan based hydrogel membranes facilitate re-epithelization in diabetic model

Healthcare professionals face an ongoing challenge in managing both acute and chronic wounds, given the potential impact on patients' quality of life and the limited availability of expensive treatment options. Hydrogel wound dressings offer a promising solution for effective wound care due to their affordability, ease of use, and ability to incorporate bioactive substances that enhance the wound healing process. Our study aimed to develop and evaluate hybrid hydrogel membranes enriched with bioactive components such as collagen and hyaluronic acid. We utilized both natural and synthetic polymers and employed a scalable, non-toxic, and environmentally friendly production process. We conducted extensive testing, including an in vitro assessment of moisture content, moisture uptake, swelling rate, gel fraction, biodegradation, water vapor transmission rate, protein denaturation, and protein adsorption. We evaluated the biocompatibility of the hydrogel membranes through cellular assays and performed instrumental tests using scanning electron microscopy and rheological analysis. Our findings demonstrate that the biohybrid hydrogel membranes exhibit cumulative properties with a favorable swelling ratio, optimal permeation properties, and good biocompatibility, all achieved with minimal concentrations of bioactive agents.

Metal–phenolic network-based polydopamine@Cu within a polyvinyl alcohol hydrogel film for improved infected wound healing through antibacterial and pro-angiogenesis activity