Alginate/polyvinyl alcohol films for wound healing: Advantages and challenges

Design and Characterization of Polyvinyl Alcohol/Kappa-Carrageenan Pickering Emulsion Biocomposite Films for Potential Wound Care Applications

This study aimed to develop polyvinyl alcohol (PVA) and kappa-carrageenan (κCA) biocomposite films using a Pickering emulsion technique for wound care applications. Juniper essential oil and modified sepiolite were incorporated to enhance functionality, with films prepared via solvent casting and characterized for structural, thermal, and mechanical properties. The PCOS-2 film exhibited the highest mechanical performance, with Young's modulus of 6.25 ± 1.3 MPa, tensile strength of 5.65 ± 1.7 MPa, and elongation at break of 608.96% ± 72.8%. Antibacterial assays showed inhibition zones of 9 and 10 mm against Staphylococcus aureus and Escherichia coli, respectively, for the PCOS-2 film, while antioxidant activity reached 63% DPPH radical scavenging after 12 h. Additionally, porosity and hydrophilicity were enhanced, as indicated by contact angles of 55° for the control film and 71.2° for PCOS-2. These results underscore the potential of PVA/κCA biocomposite films as sustainable and bioactive wound dressings, combining mechanical resilience, bioactivity, and environmental compatibility, with future efforts focused on optimizing antibacterial efficacy against gram-negative bacteria and clinical validation.

Silver Nanowire-Coated Porous Alginate Films for Wound Dressing Applications: Antibacterial Activity, Cell Proliferation, and Physical Characterization

In the present study, porous calcium alginate films have been developed by the addition of 0.02, 0.1, and 0.5% (w/v) PVA to sodium alginate film solutionss. Poly(vinyl) alcohol played the role of a pore-forming agent for calcium alginate films, and the controlled pore sizes of the films were investigated by scanning electron microscopy and Fourier transform infrared spectroscopy analyses. Human fibroblast cell attachment was performed on the porous calcium alginate films (0.5-Ca-Alg), and then the film was coated with 1 and 3 wt % silver nanowires. Cell proliferation was enhanced on films after the coating of the silver nanowires. The MTT assay was performed on the calcium alginate films and silver nanowire-coated films, and the films were found to be nontoxic to human foreskin fibroblast cells at the end of 72 h of exposure. The existence of silver nanowires on the porous calcium alginate film endowed the material with good antibacterial activity. The swelling ability of the porous and silver nanowire-coated film (0.5-Ca-Alg-1/AgNW) increased by ∼64% in simulated body fluid (pH = 7.4) and distilled water compared to a nonporous film (Ca-Alg). The water vapor transmission rate of Ca-Alg was ∼45% enhanced thanks to the porosity of films and the existence of AgNW. Hereby, it is demonstrated that the novel silver nanowire-doped porous alginate materials would be potential wound dressing agents with desired physical properties, antibacterial activity, and availability to cell proliferation.

Capsaicin/silica-infused polygalacturonic acid/polyvinyl alcohol nano-matrix for enhanced wound healing in skin injuries

Wound healing is a complex physiological process, demanding advanced strategies for efficient tissue regeneration. To address this, we developed a novel nanofibrous matrix composed of polygalacturonic acid (PGA), polyvinyl alcohol (PVA), capsaicin, and zinc-doped mesoporous silica (Zn/MCM-41). This copolymeric matrix offers enhanced mechanical stability, controlled drug release, and improved cellular adhesion and proliferation, leading to effective tissue regeneration. Infusing capsaicin/Zn-MCM-41 confers synergistic advantages, including accelerated wound closure, diminished inflammation, and enhanced tissue regeneration, culminating in superior wound healing outcomes. Comprehensive physicochemical characterization of the nanofiber was conducted, employing techniques such as EDS, EDX, XRD, FESEM, HRTEM, FTIR, BET, TGA, DSC and Zeta potential, confirming the successful synthesis of Zn/MCM-41 at the nanoscale, exhibiting uniform porosity, colloidal stability, and thermal resilience. In vivo quantitative assessment demonstrates a significant acceleration in wound healing facilitated by the composite nanofibers. Furthermore, the incorporation of capsaicin into Zn/MCM-41 augments the wound healing process, as corroborated by histological evaluations. In summary, our investigation introduces an advanced composite nanofiber formulation that promotes accelerated wound healing quantitatively through the synergistic amalgamation of PVA, PGA, capsaicin, and Zn/MCM-41. The demonstrated efficacy of the nanofibers underscores their potential in translational regenerative medicine and wound healing applications.

Preparation and characterization of Pistacia atlantica oleo-gum-resin-loaded electrospun nanofibers and evaluating its wound healing activity in two rat models of skin scar and burn wound

Background

A growing body of research is dedicated to developing new therapeutic agents for wound healing with fewer adverse effects. One of the proceedings being taken today in wound healing research is to identify promising biological materials that not only heal wounds but also vanish scarring. The effectiveness of nanofibers like polyvinyl alcohol (PVA), in improving wound healing can be related to their unique properties. Pistacia atlantica Desf. subsp. kurdica (Zohary) Rech. f. (PAK) [Anacardiaceae], also known as "Baneh" in traditional Iranian medicine, is one of the most effective herbal remedies for the treatment of different diseases like skin injuries due to its numerous pharmacological and biological properties, including anti-inflammatory, antioxidant, and anti-bacterial effects.

Purpose

Our study aimed to evaluate the wound-healing activity of nanofibers containing PVA/PAK oleo-gum-resin in two rat models of burn and excision wound repair.

Material and Methods

PVA/PKA nanofibers were prepared using the electrospinning method. Scanning electron microscope (SEM) images and mechanical properties of nanofibers were explored. Diffusion and releasing experiments of nanofibers were performed by the UV visible method at different time intervals and up to 72 h. The animal models were induced by excision and burn in Wistar rat's skin and the wound surface area was measured during the experiment for 10 and 21 days, respectively. On the last day, the wound tissue was removed for histological studies, and serum oxidative factors were measured to evaluate the antioxidant properties of the PVA/PKA. Data analysis was performed using ImageJ, Expert Design, and statistical analysis methods.

Results and discussion

PVA/PKA nanofibers were electrospun at different voltages (15, 18, and 20 kV). The most suitable fibers were obtained when the nozzle was positioned 15 cm away from the collector, with a working voltage of 15 kV, and an injection rate of 0.5 mm per hour, using the 30:70 w/v PKA gum. In the SEM images, it was found that the surface tension of the polymer solution decreased by adding the gum and yield thinner and longer fibers at a voltage of 15 kV with an average diameter of 96 ± 24 nm. The mechanical properties of PVA/PKA nanofibers showed that the presence of gum increased the tensile strength and decreased the tensile strength of the fibers simultaneously. In vivo results showed that PVA/PKA nanofibers led to a significant reduction in wound size and tissue damage (regeneration of the epidermal layer, higher density of dermal collagen fibers, and lower presence of inflammatory cells) compared to the positive (phenytoin and silver sulfadiazine) and negative control (untreated) groups. Wound contraction was higher in rats treated with PVA/PKA nanofibers. Additionally, antioxidative serum levels of catalase and glutathione were higher in the PVA/PKA nanofiber groups even in comparison to positive control groups.

Conclusion

Pistacia atlantica oleo-gum-resin-loaded electrospun nanofibers potentially improve excision and burn models of skin scars in rats through antioxidative and tissue regeneration mechanisms.

Development of Antioxidant-Active Sericin-Curcumin-Loaded Sodium Alginate/Polyvinyl Alcohol Films Crosslinked with Calcium Chloride as a Promising Wound Dressing Application

Silk sericin (SS) and curcumin (Cur) possess significant antioxidant properties, making them highly beneficial for wound healing applications. This study aimed to develop SS-Cur-loaded sodium alginate/polyvinyl alcohol (SA/PVA) films crosslinked with calcium chloride, creating a biomaterial with enhanced stability and antioxidant properties. Wound dressings containing SS-Cur were fabricated by mixing SA and PVA at different ratios of 1:1, 1:2, 1:4, and 1:6. The resulting films were then crosslinked with calcium chloride in an ethanol solution to enhance film integrity. These films were characterized using several techniques, revealing that the presence of ethanol in calcium chloride affected film properties, including the gel fraction, swelling, film thickness, and FTIR analysis. The presence of ethanol in calcium chloride revealed the highest drug content in the SA/PVA films. In vitro release studies demonstrated sustained release of SS-Cur from all formulations. Cytotoxicity and antioxidant activity tests showed that SS-Cur-loaded SA/PVA films with ethanol in calcium chloride increased cell viability and enhanced antioxidant effects in L929 cells. In conclusion, this study demonstrates that the presence of ethanol in the crosslinking solution improved the functionality of SS-Cur-loaded SA/PVA films, making them promising candidates for wound healing and soft tissue regeneration.

Troxerutin associated with Agaricus blazei Murill polysaccharides in films improves full-thickness wound healing

The present study aimed to associate troxerutin (TRX) with polysaccharides from Agaricus blazei Murill mushroom (PolyAb) in alginate/PVA films and evaluate their effect on wound healing. The physicochemical, mechanical, morphological, and water vapor barrier properties of the films were studied, and their biological potential was analyzed in vivo using the full-thickness wound healing model. The association between TRX and PolyAb present in the polymeric film contributed to increased thermal stability, mechanical resistance, and elasticity when compared to films without TRX, which indicated good miscibility of the excipients. In the in vivo tests, the TRX films promoted greater collagen deposition and repair of epidermis and dermis layers. The 0.25 % TRX film showed an increase in reduced glutathione levels, while the 1.0 % TRX film reduced lipid peroxidation and production of the pro-inflammatory cytokine IL-1β, demonstrating the anti-inflammatory and antioxidant effect of TRX films. Therefore, it is estimated that the film containing 1 % TRX can be used as biocurative for wound dressing applications.

Inula helenium extract and lidocaine-loaded electrospun wound dressings for managing skin wounds pain and their healing: An in vitro and in vivo study

The skin injuries pose a substantial public health challenge, not only due to their physical trauma but also the accompanying pain and complexities in wound healing. In the current research, Inula helenium extract and lidocaine were loaded into electrospun PVA/calcium alginate nanofibers to promote skin wounds healing and alleviate the resulting pain. Various in vitro experiments were utilized to characterize these dressings. Wound healing potential of these constructs and their analgesic effects were studied in a rat model of skin wounds. Our developed scaffolds released the loaded drugs in a slow manner and showed antioxidative and anti-inflammatory activities. Fiber size measurement showed that drug-loaded and drug-free scaffolds had around 418.025 ± 140.11 nm and 505.51 ± 93.29 nm mean fiber size, respectively. Bacterial penetration assay confirmed that drug-loaded scaffolds reduced bacterial infiltration through the matrices. Wound healing study showed that on day 14th, the dressings loaded with inula helenium extract and lidocaine could close the wounds up to 91.26 ± 5.93%. In addition, these scaffolds significantly reduced the animals pain sensitivity. ELISA assay results implied that these dressings modulated inflammation and reduced tissue's oxidative stress.

Phosphorus and nitrogen supramolecule for fabricating flame-retardant, transparent and robust polyvinyl alcohol film

Supramolecular flame retardants have attracted increasing attention recently due to their simple and eco-friendly preparation process. In this study, a novel flame retardant HEPFR was prepared using supramolecular self-assembly technology between piperazine and 1-hydroxy ethylidene-1,1-diphosphonic acid (HEDP). It was introduced into polyvinyl alcohol (PVA) matrix to form PVA/HEPFR composite film. Subsequently, the transparency, mechanical properties, thermal stability, and flame retardancy of PVA/HEPFR films were studied. Due to the hydrogen bonded cross-linked network structure between PVA and HEPFR, the mechanical properties of PVA/HEPFR films have been improved, while maintaining good transparency. With 10 wt% addition of HEPFR, PVA films can reach the VTM-0 level in UL-94 testing. And the limiting oxygen index can be increased from 18.5% of pure PVA to 26.5%. The peak heat release rate was reduced by 61.5%. The flame retardancy and thermal stability of PVA/HEPFR films have been greatly improved. This study provides a "one stone, three birds" strategy for preparing flame-retardant, transparent, and robust PVA film.

Bioactive material‑sodium alginate-polyvinyl alcohol composite film scaffold for bone tissue engineering application

Road accidents and infection-causing diseases during bone surgery are serious problems in orthopedics, and thus, addressing these pressing challenges is crucial. In the present study, the 70S30C calcium silicate bioactive material (BM) is synthesized by a sustainable approach employing a precipitation method using recycled rice husk and eggshells as a precursor of silica and calcium. Further, 70S30C BM is composited with sodium alginate (SA) and polyvinyl alcohol (PVA), and the films were prepared by solvent casting method. The composite films were prepared without the addition of acid, binder, and crosslinking agents. Further, the films were characterized by BET, XRD, ATR-FTIR, SEM, and EDS mapping. The in vitro bioactivity and biodegradation study is performed in the simulated body fluid (SBF). The in vitro haemolysis study is executed using human blood and the results demonstrate haemocompatibility of the composite films. The ex ovo CAM assay also exhibits good neovascularization. The in vitro and in vivo biocompatibility assay proves its non-toxic nature. Further, the in vivo study reveals that the engineered composite film demonstrates accelerated osteogenesis. This work broadens the orthopedic potential of the composite film and offers bioactivity, haemocompatibility, angiogenesis, non-toxicity, and in vivo osteogenesis which would serve as a potential candidate for bone tissue engineering application.

A hybrid structure based on silk fibroin/PVA nanofibers and alginate/gum tragacanth hydrogel embedded with cardamom extract

Hybrid structures made of natural-synthetic polymers have been interested due to high biological features combining promising physical-mechanical properties. In this research, a hybrid dressing consisting of a silk fibroin (SF)/polyvinyl alcohol (PVA) nanofibers and sodium alginate (SA)/gum tragacanth (GT) hydrogel incorporating cardamom extract as an antibacterial agent was prepared. Accordingly, SF was extracted from cocoons followed by electrospinning in blend form with PVA (SF/PVA ratio: 1:1) under the voltage of 18 kV and the distances of 15 cm. The SEM images confirmed the formation of uniform, bead free fibers with the average diameter of 199 ± 28 nm. FTIR and XRD results revealed the successful extraction of SF and preparation of mixed fibrous mats. Next, cardamom oil extract-loaded SA/GT hydrogel was prepared and the nanofibrous structure was placed on the surface of hydrogel. SEM analysis depicted the uniform morphology of hybrid structure with desirable matching between two layers. TGA analysis showed desired thermal stability. The swelling ratio was found to be 1251% after 24 h for the hybrid structure and the drug was released without any initial burst. MTT assay and cell attachment results showed favorable biocompatibility and cell proliferation on samples containing extract, and antibacterial activity values of 85.35% against S. aureus and 75% against E. coli were obtained as well. The results showed that the engineered hybrid nanofibrous-hydrogel film structure incorporating cardamom oil extract could be a promising candidate for wound healing applications and skin tissue engineering.

Resveratrol-Ampicillin Dual-Drug Loaded Polyvinylpyrrolidone/Polyvinyl Alcohol Biomimic Electrospun Nanofiber Enriched with Collagen for Efficient Burn Wound Repair

Background

The healing of burn wounds is a complicated physiological process that involves several stages, including haemostasis, inflammation, proliferation, and remodelling to rebuild the skin and subcutaneous tissue integrity. Recent advancements in nanomaterials, especially nanofibers, have opened a new way for efficient healing of wounds due to burning or other injuries.

Methods

This study aims to develop and characterize collagen-decorated, bilayered electrospun nanofibrous mats composed of PVP and PVA loaded with Resveratrol (RSV) and Ampicillin (AMP) to accelerate burn wound healing and tissue repair.

Results

Nanofibers with smooth surfaces and web-like structures with diameters ranging from 200 to 400 nm were successfully produced by electrospinning. These fibres exhibited excellent in vitro properties, including the ability to absorb wound exudates and undergo biodegradation over a two-week period. Additionally, these nanofibers demonstrated sustained and controlled release of encapsulated Resveratrol (RSV) and Ampicillin (AMP) through in vitro release studies. The zone of inhibition (ZOI) of PVP-PVA-RSV-AMP nanofibers against Staphylococcus aureus (S. aureus) and Escherichia coli (E. coli) was found 31±0.09 mm and 12±0.03, respectively, which was significantly higher as compared to positive control. Similarly, the biofilm study confirmed the significant reduction in the formation of biofilms in nanofiber-treated group against both S. aureus and E. coli. X-ray diffraction (XRD) and Fourier transform infrared spectroscopy (FTIR) analysis proved the encapsulation of RSV and AMP successfully into nanofibers and their compatibility. Haemolysis assay (%) showed no significant haemolysis (less than 5%) in nanofiber-treated groups, confirmed their cytocompatibility with red blood cells (RBCs). Cell viability assay and cell adhesion on HaCaT cells showed increased cell proliferation, indicating its biocompatibility as well as non-toxic properties. Results of the in-vivo experiments on a burn wound model demonstrated potential burn wound healing in rats confirmed by H&E-stained images and also improved the collagen synthesis in nanofibers-treated groups evidenced by Masson-trichrome staining. The ELISA assay clearly indicated the efficient downregulation of TNF-alpha and IL-6 inflammatory biomarkers after treatment with nanofibers on day 10.

Conclusion

The RSV and AMP-loaded nanofiber mats, developed in this study, expedite burn wound healing through their multifaceted approach.

Therapeutic Potential of Nanocarrier Mediated Delivery of Peptides for Wound Healing: Current Status, Challenges and Future Prospective

Wound healing presents a complex physiological process that involves a sequence of events orchestrated by various cellular and molecular mechanisms. In recent years, there has been growing interest in leveraging nanomaterials and peptides to enhance wound healing outcomes. Nanocarriers offer unique properties such as high surface area-to-volume ratio, tunable physicochemical characteristics, and the ability to deliver therapeutic agents in a controlled manner. Similarly, peptides, with their diverse biological activities and low immunogenicity, hold great promise as therapeutics in wound healing applications. In this review, authors explore the potential of peptides as bioactive components in wound healing formulations, focusing on their antimicrobial, anti-inflammatory, and pro-regenerative properties. Despite the significant progress made in this field, several challenges remain, including the need for standardized characterization methods, optimization of biocompatibility and safety profiles, and translation from bench to bedside. Furthermore, developing multifunctional nanomaterial-peptide hybrid systems represents promising avenues for future research. Overall, the integration of nanomaterials made up of natural or synthetic polymers with peptide-based formulations holds tremendous therapeutic potential in advancing the field of wound healing and improving clinical outcomes for patients with acute and chronic wounds.

Fabrication of yeast β-glucan/sodium alginate/γ-polyglutamic acid composite particles for hemostasis and wound healing

Particles with a porous structure can lead to quick hemostasis and provide a good matrix for cell proliferation during wound healing. Recently, many particle-based wound healing materials have been clinically applied. However, these products show good hemostatic ability but with poor wound healing ability. To solve this problem, this study fabricated APGG composite particles using yeast β-glucan (obtained from Saccharomyces cerevisiae), sodium alginate, and γ-polyglutamic acid as the starting materials. The structure of yeast β-glucan was modified with many carboxymethyl groups to obtain carboxymethylated β-glucan, which could coordinate with Ca2+ ions to form a crosslinked structure. A morphology study indicated that the APGG particles showed an irregular spheroidal structure with a low density (<0.1 g cm-3) and high porosity (>40%). An in vitro study revealed that the particles exhibited a low BCI value, low hemolysis ratio, and good cytocompatibility against L929 cells. The APGG particles could quickly stop bleeding in a mouse liver injury model and exhibited better hemostatic ability than the commercially available product Celox. Furthermore, the APGG particles could accelerate the healing of non-infected wounds, and the expression levels of CD31, α-SMA, and VEGF related to angiogenesis were significantly enhanced.

AI energized hydrogel design, optimization and application in biomedicine

Traditional hydrogel design and optimization methods usually rely on repeated experiments, which is time-consuming and expensive, resulting in a slow-moving of advanced hydrogel development. With the rapid development of artificial intelligence (AI) technology and increasing material data, AI-energized design and optimization of hydrogels for biomedical applications has emerged as a revolutionary breakthrough in materials science. This review begins by outlining the history of AI and the potential advantages of using AI in the design and optimization of hydrogels, such as prediction and optimization of properties, multi-attribute optimization, high-throughput screening, automated material discovery, optimizing experimental design, and etc. Then, we focus on the various applications of hydrogels supported by AI technology in biomedicine, including drug delivery, bio-inks for advanced manufacturing, tissue repair, and biosensors, so as to provide a clear and comprehensive understanding of researchers in this field. Finally, we discuss the future directions and prospects, and provide a new perspective for the research and development of novel hydrogel materials for biomedical applications.

Characterizations of Centrifugal Electrospun Polyvinyl Alcohol/Sodium Alginate/Tamanu Oil/Silver Nanoparticles Wound Dressing

Known for its water solubility, flexibility, strong adhesion, and eco-friendly nature, polyvinyl alcohol (PVA) is widely used in various industries. In the medical field, it is used for applications such as creating bandages and orthopaedic devices. Incorporating sodium alginate (SA) into PVA membranes enhances their structural integrity, breathability, and permeability, thereby minimising the risk of cellular damage in the wound zone. Moreover, the addition of tamanu oil (C alophyllum inophyllum L.) and silver nanoparticles, both of which are known for their antibacterial properties and benefits in traditional wound healing, further enhances the membranes' wound-healing effectiveness. Following production, the membranes undergo a series of tests designed to evaluate their physical properties as well as their antioxidant and antibacterial capabilities. Subsequently, in vitro testing is conducted using human skin cells; experiments on Wistar rats are then performed. Numerous experiments have consistently demonstrated that the performance of polyvinyl alcohol/sodium alginate/tamanu oil (PVA/SA/Oil) membrane is superior to that of polyvinyl alcohol/sodium alginate/tamanu oil/silver nanoparticles (PVA/SA/Oil/Ag NP) membrane. Specifically, the polyvinyl alcohol/sodium alginate (PVA/SA) combination exhibits an impressive wound-healing rate of 98.82% after 15 days, with cells maintaining a high viability of 92% in a nourishing environment. Moreover, these membranes exhibit exceptional resistance to the oxidation of free radicals, surpassing the 70% threshold, and they possess antibacterial activity against Staphylococcus aureus subsp. aureus in vitro. Based on the obtained results, the nanofiber membranes composed of polyvinyl alcohol/ alginate/ tamanu oil, with or without silver nanoparticles, have shown potential as wound dressings in the wound care discipline.

Chitosan-based films filled with nanoencapsulated essential oil: Physical-chemical characterization and enhanced wound healing activity

The economic burden of chronic wounds, the complexity of the process of tissue repair and the possibility of resistant bacterial infections, have triggered a significant research interest in the application of natural alternative therapies for wound healing. Biomolecules are intrinsically multi-active, as they affect multiple mechanisms involved in tissue repair phenomenon, including immunomodulatory, anti-inflammatory, cell proliferation, extra cellular matrix remodeling and angiogenesis. Chitosan features a unique combination of attributes, including intrinsic hemostatic, antimicrobial, and immunomodulatory properties, that make it an exceptional candidate for wound management, in the development of wound dressings and scaffolds. In this study, we produced nanoemulsions (NE) loaded with SFO, characterized them, and evaluated their tissue repairing properties. Dynamic light scattering (DLS) analysis confirmed the formation of a nanoemulsion with a droplet size of 21.12 ± 2.31 nm and a polydispersity index (PdI) of 0.159, indicating good stability for up to 90 days. To investigate the potential wound healing effects, SFO-loaded NE were applied on male C57BL/6 mice for seven consecutive days, producing a significantly higher wound closure efficiency (p < 0.05) for the group treated with SFO-loaded NE compared to the control group treated with the saline solution. This finding indicates that the SFO-loaded NE exhibits therapeutic properties that effectively promote wound healing in this experimental model. Then, SFO-loaded NE were incorporated into chitosan:polyvinyl alcohol (PVA)-based films. The inclusion of NE into the polymer matrix resulted in increased lipophilicity reflected by the contact angle results, while decreasing moisture absorption, water solubility, and crystallinity. Moreover, FTIR analysis confirmed the formation of new bonds between SFO-NE and the film matrix, which also impacted on porosity properties. Thermal analysis indicated a decrease in the glass transition temperature of the films due to the presence of SFO-NE, suggesting a plasticizing role of NE, confirmed by XRD results, that showed a decrease in the crystallinity of the blend films upon the addition of SFO-NE. AFM images showed no evidence of NE droplet aggregation in the Chitosan:PVA film matrix. Moisture absorption and water content decreased upon incorporation of SFO-loaded NE. Although the inclusion of NE increased hydrophobicity and water contact angle, the values remained within an acceptable range for wound healing applications. Overall, our results emphasize the significant tissue repairing properties of SFO-loaded NE and the potential of Chitosan:PVA films containing nanoencapsulated SFO as effective formulations for wound healing with notable tissue repairing properties.

Surface modification strategies for improved hemocompatibility of polymeric materials: a comprehensive review

Polymeric biomaterials are a widely used class of materials due to their versatile properties. However, as with all other types of materials used for biomaterials, polymers also have to interact with blood. When blood comes into contact with any foreign body, it initiates a cascade which leads to platelet activation and blood coagulation. The implant surface also has to encounter a thromboinflammatory response which makes the implant integrity vulnerable, this leads to blood coagulation on the implant and obstructs it from performing its function. Hence, the surface plays a pivotal role in the design and application of biomaterials. In particular, the surface properties of biomaterials are responsible for biocompatibility with biological systems and hemocompatibility. This review provides a report on recent advances in the field of surface modification approaches for improved hemocompatibility. We focus on the surface properties of polysaccharides, proteins, and synthetic polymers. The blood coagulation cascade has been discussed and blood - material surface interactions have also been explained. The interactions of blood proteins and cells with polymeric material surfaces have been discussed. Moreover, the benefits as well as drawbacks of blood coagulation on the implant surface for wound healing purposes have also been studied. Surface modifications implemented by other researchers to enhance as well as prevent blood coagulation have also been analyzed.

Nanoapatite-Loaded κ-Carrageenan/Poly(vinyl alcohol)-Based Injectable Cryogel for Hemostasis and Wound Healing

Immediate control of excessive bleeding and prevention of infections are of utmost importance in the management of wounds. Cryogels have emerged as promising materials for the rapid release of medication and achieving hemostasis. However, their quick release properties pose the challenge of exposing patients to high concentrations of drugs. In this study, hybrid nanocomposites were developed to address this issue by combining poly(vinyl alcohol) and κ-carrageenan with whitlockite nanoapatite (WNA) particles and ciprofloxacin, aiming to achieve rapid hemostasis and sustained antibacterial effects. A physically cross-linked cryogel was obtained by subjecting a blend of poly(vinyl alcohol) and κ-carrageenan to successive freezing-thawing cycles, followed by the addition of WNA. Furthermore, ciprofloxacin was introduced into the cryogel matrix for subsequent evaluation of its wound healing properties. The resulting gel system exhibited a 3D microporous structure and demonstrated excellent swelling, low cytotoxicity, and outstanding mechanical properties. These characteristics were evaluated through analytical and rheological experiments. The nanocomposite cryogel with 4% whitlockite showed extended drug release of 71.21 ± 3.5% over 21 days and antibacterial activity with a considerable growth inhibition zone (4.19 ± 3.55 cm). Experiments on a rat model demonstrated a rapid hemostasis property of cryogels within an average of 83 ± 4 s and accelerated the process of wound healing with 96.34% contraction compared to the standard, which exhibited only ∼78% after 14 days. The histopathological analysis revealed that the process of epidermal re-epithelialization took around 14 days following the skin incision. The cryogel loaded with WNAs and ciprofloxacin holds great potential for strategic utilization in wound management applications as an effective material for hemostasis and anti-infection purposes.

FTIR, 1H, and 13C NMR Characterization and Antibacterial Activity of the Combination of Euphorbia Honey and Potato Starch

AIM AND OBJECTIVE

In recent years, natural biopolymer (potato starch) hydrogels have been widely used in the field of wound dressing material. This study aimed to develop and characterize a novel antibacterial hydrogel made from potato starch and natural honey.

METHODS

The structure of the composite films was evaluated by Fourier transform infrared (FTIR) and 1H,13C nuclear magnetic resonance (NMR) spectroscopy, and the antibacterial activities were tested by agar diffusion method. FTIR analysis showed chemical interaction between the components of Euphorbia honey (EH) and potato starch hydrogel (PSH).

RESULTS

The 1H-13C NMR and FTIR analyses of EH/PSH confirmed their structure and showed the presence of glucose and hydrocarbon derivatives. After 24 h of incubation, the EH/PSH hydrogel showed good antibacterial activity against three bacterial strains (K.pneumonia, P.mirabilis, and P. aeruginosa) by producing clear inhibition zones of 12.33 ± 1.88 mm, 15.33 ± 0.94, and 10 ± 0 mm, respectively. In addition, K. pneumonia, P. mirabilis, and P. aeruginosa were sensitive to the EH/SPH with a minimum inhibitory concentration (MIC) of 1 %.

CONCLUSION

These results suggest that EH-PS has potential as an alternative candidate to conventional antibiotics.

Enhanced physical properties, antioxidant and antibacterial activity of bio-composite films composed from carboxymethyl cellulose and polyvinyl alcohol incorporated with broccoli sprout seed extract for butter packaging

This study investigated the development of biodegradable films made from a combination of carboxymethyl cellulose (CMC), Polyvinyl alcohol (PVA), and purified extract of broccoli sprout seed (BSSE). The films were characterized for their color, physical properties, surface morphology, crystallinity, mechanical properties, and thermal properties. The addition of BSSE up to 1.4 % to the film matrix imparted opaque color and increased opacity up to 3.652. The films also became less moisture-absorbent 8.21 %, soluble 19.16 %, and permeable to water vapor 1.531 (× 10-10 g.m-1 s-1 pa-1). By utilizing 0.7 % from BSSE inside films, the surface of the films became smoother but became rough with higher concentrations 2.1 % of BSSE. Fourier transform infrared (FT-IR) analysis showed that there was physical interaction between the BSSE extract and the PV/CM matrix. The films showed good thermal stability, and the incorporation of BSSE improved their ability to preserve the acidity, TBARS, peroxide value, and total color differences of butter during cold storage.

Sodium alginate hydrogel integrated with type III collagen and mesenchymal stem cell to promote endometrium regeneration and fertility restoration

A thinner endometrium has been linked to implantation failure, and various therapeutic strategies have been attempted to improve endometrial regeneration, including the use of mesenchymal stem cells (MSCs). However, low survival and retention rates of transplanted stem cells are main obstacles to efficient stem cell therapy in thin endometrium. Collagen type III is a key component of the extracellular matrix, plays a crucial role in promoting cell proliferation and differentiation, and has been identified as the major collagen expressed at the implantation site. Herein, composite alginate hydrogel containing recombinant type III collagen (rCo III) and umbilical cord mesenchymal stem cells are developed. rCo III serves as favorable bioactive molecule, displaying that rCo III administration promotes MSCs proliferation, stemness maintenance and migration. Moreover, rCo III administration enhances cell viability and migration of mouse endometrial stromal cells (ESCs). In a mouse model of thin endometrium, the Alg-rCo III hydrogel loaded with MSCs (MSC/Alg-rCo III) significantly induces endometrial regeneration and fertility enhancement in vivo. Further studies demonstrate that the MSC/Alg-rCo III hydrogel promoted endometrial function recovery partly by regulating mesenchymal-epithelial transition of ESCs. Taken together, the combination of Alg-rCo III hydrogel and MSCs has shown promising results in promoting endometrium regeneration and fertility restoration, and may provide new therapeutic options for endometrial disease.

In Situ Hydrogel Formulation for Advanced Wound Dressing: Influence of Co-Solvents and Functional Excipient on Tailored Alginate-Pectin-Chitosan Blend Gelation Kinetics, Adhesiveness, and Performance

Chronic skin wounds affect more than 40 million patients worldwide, representing a huge problem for healthcare systems. This study elucidates the optimization of an in situ gelling polymer blend powder for biomedical applications through the use of co-solvents and functional excipients, underlining the possibility of tailoring microparticulate powder properties to generate, in situ, hydrogels with advanced properties that are able to improve wound management and patient well-being. The blend was composed of alginate, pectin, and chitosan (APC). Various co-solvents (ethanol, isopropanol, and acetone), and salt excipients (sodium bicarbonate and ammonium carbonate) were used to modulate the gelation kinetics, rheology, adhesiveness, and water vapor transmission rate of the gels. The use of co-solvents significantly influenced particle size (mean diameter ranging from 2.91 to 5.05 µm), depending on the solvent removal rate. Hydrogels obtained using ethanol were able to absorb over 15 times their weight in simulated wound fluid within just 5 min, whereas when sodium bicarbonate was used, complete gelation was achieved in less than 30 s. Such improvement was related to the internal microporous network typical of the particle matrix obtained with the use of co-solvents, whereas sodium bicarbonate was able to promote the formation of allowed particles. Specific formulations demonstrated an optimal water vapor transmission rate, enhanced viscoelastic properties, gel stiffness, and adhesiveness (7.7 to 9.9 kPa), facilitating an atraumatic removal post-use with minimized risk of unintended removal. Microscopic analysis unveiled that porous inner structures were influencing fluid uptake, gel formation, and transpiration. In summary, this study provided valuable insights for optimizing tailored APC hydrogels as advanced wound dressings for chronic wounds, including vascular ulcers, pressure ulcers, and partial and full-thickness wounds, characterized by a high production of exudate.

Hydrogel loaded with exosomes from Whartons Jelly-derived mesenchymal stem cells enhances wound healing in mice

OBJECTIVES

To explore the effect of hydrogel loaded with exosomes from Wharton's Jelly-derived mesenchymal stem cell (WJMSC) on wound healing.

METHODS

Exosomes were extracted from WJMSC, and the morphology and size of WJMSC-derived exosomes (WEX) were analyzed by transmission electron microscopy and nanoparticle size analyzer, respectively. The surface markers CD9, CD81, and Calnexin of WEX were detected by Western blotting. Exosome-loaded alginate hydrogel (WEX-gel) was prepared; its morphology was studied by scanning electron microscope, and its rheological behavior was examined by a rheometer. The in vitro drug release performance of WEX-gel was investigated by BCA method. RAW264.7 cells were treated with alginate hydrogel, WEX and WEX-gel, respectively; and the expression of CD86 and CD206 in macrophages was detected by flow cytometry. A full-thickness skin wound model was established in mice; the model mice were randomly divided into blank control group, WEX control group and WEX-gel group, and PBS, WEX and WEX-gel were applied to the wound area of mice, respectively. On day 3, the skin tissue of mice was excised, and the antibacterial effect of WEX hydrogel was evaluated by plate counting. On day 15, the mice were euthanized and the percentage of residual wounds was calculated. The histological changes of the skin wound were observed after hematoxylin and eosin (HE) and Masson stainings. The expression of CD86, CD206, CD31 and vascular endothelial growth factor (VEGF) in the skin wound tissue was detected by immunohistochemistry.

RESULTS

Exosomes were successfully extracted from WJMSC. WEX-gel presented a regular three-dimensional network structure, good rheology and controlled drug release performance. WEX-gel promoted the polarization of RAW264.7 cells from the M1 phenotype to M2 phenotype in vitro. The residual wound percentage in blank control group, WEX control group and WEX-gel group were (27.5±3.4)%, (15.3±1.2)% and (7.6±1.1)%, respectively (P<0.05). The antibacterial property of WEX-gel is better than that of WEX (P<0.05). The dermis thickness, the number of new hair follicles, and the rate of collagen deposition in the WEX-gel group were significantly higher than those in the other two groups (all P<0.05). The expression of CD206, CD31 and VEGF in skin wound tissue was higher and the expression of CD86 was lower in WEX-gel group than those in other two groups (all P<0.05).

CONCLUSIONS

WEX-gel can significantly promote wound healing in mice by regulating the polarization of macrophages.

Optimization of the Green Extraction of Red Araçá (Psidium catteyanum Sabine) and Application in Alginate Membranes for Use as Dressings

In this research, the aim was to introduce innovation to the pharmaceutical field through the exploration of an underutilized plant matrix, the red araçá, along with the utilization of sodium alginate for the development of membranes designed for active topical dressings. Within this context, optimal extraction conditions were investigated using the central composite rotational statistical design (CCRD) to obtain a red araçá epicarp extract (RAEE) rich in bioactive compounds utilizing the maceration technique. The extract acquired under the optimized conditions (temperature of 66 °C and a hydroalcoholic solvent concentration of 32%) was incorporated into a sodium alginate matrix for the production of active membranes using a casting method. Characterization of the membranes revealed that the addition of the extract did not significantly alter its morphology. Furthermore, satisfactory results were observed regarding mechanical and barrier properties, as well as the controlled release of phenolic compounds in an environment simulating wound exudate. Based on these findings, the material produced from renewable matrices demonstrates the promising potential for application as a topical dressing within the pharmaceutical industry.

Effect of Polydopamine and Curcumin on Physicochemical and Mechanical Properties of Polymeric Blends

In this study, we prepared composites made from polyvinyl alcohol (PVA), sodium alginate (SA), curcumin (Cur), and polydopamine (PD). The film-forming properties of the composites were researched for potential wound-healing applications. The structures of the polymer blends and composites were studied by FTIR spectroscopy and microscopic observations (AFM and SEM). The mechanical properties were measured using a Zwick Roell testing machine. It was observed that the formation of a polymeric film based on the blend of polyvinyl alcohol and sodium alginate led to the generation of pores. The presence of curcumin in the composite resulted in the alteration of the blend properties. After solvent evaporation, the polymeric blend of PVA, SA, and curcumin formed a stable polymeric film, but the film showed poor mechanical properties. The addition of polydopamine led to an improvement in the mechanical strength of the film and an increase in its surface roughness. A polymeric film of sodium alginate presented the highest surface roughness value among all the studied specimens (66.6 nm), whereas polyvinyl alcohol showed the lowest value (1.60 nm). The roughness of the composites made of PVA/SA/Cur and PVA/SA/Cur/PD showed a value of about 25 nm. Sodium alginate showed the highest values of Young's modulus (4.10 GPa), stress (32.73 N), and tensile strength (98.48 MPa). The addition of PD to PVA/SA/Cur led to an improvement in the mechanical properties. Improved mechanical properties and appropriate surface roughness may suggest that prepared blends can be used for the preparation of wound-healing materials.

Integrating Chinese Herbs and Western Medicine for New Wound Dressings through Handheld Electrospinning

In this nanotechnology era, nanostructures play a crucial role in the investigation of novel functional nanomaterials. Complex nanostructures and their corresponding fabrication techniques provide powerful tools for the development of high-performance functional materials. In this study, advanced micro-nanomanufacturing technologies and composite micro-nanostructures were applied to the development of a new type of pharmaceutical formulation, aiming to achieve rapid hemostasis, pain relief, and antimicrobial properties. Briefly, an approach combining a electrohydrodynamic atomization (EHDA) technique and reversed-phase solvent was employed to fabricate a novel beaded nanofiber structure (BNS), consisting of micrometer-sized particles distributed on a nanoscale fiber matrix. Firstly, Zein-loaded Yunnan Baiyao (YB) particles were prepared using the solution electrospraying process. Subsequently, these particles were suspended in a co-solvent solution containing ciprofloxacin (CIP) and hydrophilic polymer polyvinylpyrrolidone (PVP) and electrospun into hybrid structural microfibers using a handheld electrospinning device, forming the EHDA product E3. The fiber-beaded composite morphology of E3 was confirmed through scanning electron microscopy (SEM) images. Fourier-transform infrared (FTIR) spectroscopy and X-ray diffraction (XRD) analysis revealed the amorphous state of CIP in the BNS membrane due to the good compatibility between CIP and PVP. The rapid dissolution experiment revealed that E3 exhibits fast disintegration properties and promotes the dissolution of CIP. Moreover, in vitro drug release study demonstrated the complete release of CIP within 1 min. Antibacterial assays showed a significant reduction in the number of adhered bacteria on the BNS, indicating excellent antibacterial performance. Compared with the traditional YB powders consisting of Chinese herbs, the BNS showed a series of advantages for potential wound dressing. These advantages include an improved antibacterial effect, a sustained release of active ingredients from YB, and a convenient wound covering application, which were resulted from the integration of Chinese herbs and Western medicine. This study provides valuable insights for the development of novel multiscale functional micro-/nano-composite materials and pioneers the developments of new types of medicines from the combination of herbal medicines and Western medicines.

Agaricus blazei Murill extract-loaded in alginate/poly(vinyl alcohol) films prepared by Ca2+ cross-linking for wound healing applications

This work aimed the development and evaluation of the wound healing activity of films based on sodium alginate, polyvinyl alcohol (PVA) and Ca²⁺ loaded with Agaricus blazei Murill hydroalcoholic extract (AbE). Firstly, AbE was prepared using a previously standardized methodology. The films were prepared by casting technique and cross-linked with Ca²⁺ using CaCl₂ as cross-linking agent. The physicochemical, morphological and water vapor barrier properties of the films were analyzed and the pre-clinical efficacy was investigated against the cutaneous wound model in mice. The films showed barrier properties to water vapor promising for wound healing. AbE showed physical and chemical interactions between both polymers, noticed by Fourier transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and thermal analysis. The delivery of AbE in alginate/PVA films enhanced the antioxidant and wound healing properties of these polymers. Consequently, a reduction of malondialdehyde levels was observed, as well as an increase of the epidermis/dermis thickness and enhancement in collagen I deposition. Thus, these formulations are promising biomaterials for wound care and tissue repairing.

Electrospun Materials Based on Polymer and Biopolymer Blends-A Review

This review covers recent developments and progress in polymer and biopolymer blending and material preparation by electrospinning. Electrospinning is a technique that is used to produce nanofibers to improve the quality of membranes. Electrospun nanofibers are highly applicable in biomedical sciences, supercapacitors, and in water treatment following metal ion adsorption. The key affecting factors of electrospinning have been checked in the literature to obtain optimal conditions of the electrospinning process. Future research directions and outlooks have been suggested to think about innovative ideas for research in this field.

Polysaccharides from South Tunisian Moringa alterniflora Leaves: Characterization, Cytotoxicity, Antioxidant Activity, and Laser Burn Wound Healing in Rats

Phytochemical properties have recently increased the popularity of plant polysaccharides as wound dressing materials. This work aims at studying the structural characteristics of polysaccharides extracted from Moringa leaves (Moringa Leaves Water Soluble Polysaccharide: MLWSP), and its antioxidant activities, cytotoxic effects, and laser burn wound healing effects in rats. This MLWSP was structurally characterized. Results showed 175.21 KDa and 18.6%, respectively, for the molecular weight and the yield of the novel extracted polysaccharide. It is a hetero-polysaccharide containing arabinose, rhamnose, and galactose. XRD suggested a semi-crystalline structure of the studied polymer and FT-IR results revealed a typical polysaccharide structure. It is composed of 50 to 500 µm rocky-shaped units with rough surfaces and it was found to inhibit the proliferation of the human colon (HCT-116) (IC50 = 36 ± 2.5 µg/mL), breast (MCF-7) (IC50 = 48 ± 3.2), and ovary cancers (IC50 = 24 ± 8.1). The MLWSP showed significant antioxidant effects compared to Trolox (CI50 = 0.001 mg/g). Moreover, promising wound healing results were displayed. The effect of MLWSP hydrogel application on laser burn injuries stimulated wound contraction, re-epithelization, and remodeling phases 8 days after treatment. The wound healing potential of MLWSP may be due to its significant antioxidant activity and/or the huge amount of monosaccharide molecules.

Recent Advancement of Functional Hydrogels toward Diabetic Wound Management

Wound healing is a dynamic, orchestrated process comprising partially overlapping phases of hemostasis, inflammation, proliferation, and remodeling. This programmed process, dysregulated in diabetic individuals, results in chronic diabetic wounds. The normal process of healing halts at the inflammatory stage, and this prolonged inflammatory phase is characteristic of diabetic wounds. There are a few U.S. Food & Drug Administration approved skin substitutes; dermal matrixes are commercially available to manage diabetic wounds. However, expensiveness and nonresponsiveness in a few instances are the major limitations of such modalities. To address the issues, several treatment strategies have been exploited to treat chronic wounds; among them hydrogel-based systems showed promise due to favorable properties such as excellent absorption capabilities, porous structure, tunable mechanical strength, and biocompatibility. In the past two decades, hydrogels have become one of the most acceptable systems in the field of wound dressing material, offering single functionality to multifunctionality. This review focuses on the advancement of functional hydrogels explored for diabetic wound management. The process of diabetic wound healing is discussed in the light of the normal healing process, and the role of macrophages in the process is explained. This review also discusses the different approaches to treat diabetic wounds using functional hydrogels, along with their future opportunities.