Advances in Functional Hydrogel Wound Dressings: A Review

From lab to wearables: Innovations in multifunctional hydrogel chemistry for next-generation bioelectronic devices

Functional hydrogels have emerged as foundational materials in diagnostics, therapy, and wearable devices, owing to their high stretchability, flexibility, sensing, and outstanding biocompatibility. Their significance stems from their resemblance to biological tissue and their exceptional versatility in electrical, mechanical, and biofunctional engineering, positioning themselves as a bridge between living organisms and electronic systems, paving the way for the development of highly compatible, efficient, and stable interfaces. These multifaceted capability revolutionizes the essence of hydrogel-based wearable devices, distinguishing them from conventional biomedical devices in real-world practical applications. In this comprehensive review, we first discuss the fundamental chemistry of hydrogels, elucidating their distinct properties and functionalities. Subsequently, we examine the applications of these bioelectronics within the human body, unveiling their transformative potential in diagnostics, therapy, and human-machine interfaces (HMI) in real wearable bioelectronics. This exploration serves as a scientific compass for researchers navigating the interdisciplinary landscape of chemistry, materials science, and bioelectronics.

Screening of Short-Chain Antimicrobial Peptide LKARI with Broad-Spectrum Bactericidal Properties and Its Application in Promoting Wound Healing

Due to the extensive use of antibiotics, many highly resistant bacteria and extensively resistant bacteria have been produced. In recent years, the increase of drug-resistant bacteria and the resulting proliferation of drug-resistant bacteria have increased the incidence of hospital-acquired infections and caused great harm to human health. Antimicrobial peptides (AMPs) are considered to be an innovative antibiotic and belong to the latest advances in this field. We designed a polypeptide and verified its low minimum inhibitory concentration and broad-spectrum activity against Gram-positive bacteria, Gram-negative bacteria, and fungi in microbiology and pharmacology. Several experiments have confirmed that the screened antimicrobial peptides have significant antidrug resistance and also show significant therapeutic properties in the treatment of systemic bacterial infections. In addition, through our experimental research, it was proved that the antibacterial hydrogel composed of poly(vinyl alcohol), sodium alginate, and antimicrobial peptides had excellent antibacterial properties and showed good wound healing ability.

Metal-ion-controlled hydrogel dressing with enhanced adhesive and antibacterial properties for accelerated wound healing

In order to improve the wound repair environment, this research has successfully developed a new multifunctional hydrogel dressing, which has strong adaptability and can accelerate wound healing. Pioneering the development of metal-ion-controlled hydrogel dressings, this research integrates dopamine and imidazole double crosslinked networks with metal-ion coordination. The resulting hydrogel dressing exhibits a notable antibacterial effect and exceptional mechanical properties, withstanding pressures of up to 12 kPa, tensions of 25 kPa, and maintaining skin adhesion at 6 kPa. Furthermore, the dressing can self-heal within only 7-8 s post-injection. Impressively, the hydrogel achieves complete biodegradation within a short timeframe (37 h). Notably, the use of various metal ions facilitates painless peeling during the degradation period, perfectly aligning with the requirements of an ideal wound dressing. This study has made significant progress in the fields of trauma repair and materials, providing strong solutions for dealing with harsh post-traumatic environments.

Dual network composite hydrogels with robust antibacterial and antifouling capabilities for efficient wound healing

Wound dressings play a critical role in the wound healing process; however, conventional dressings often address singular functions, lacking versatility in meeting diverse wound healing requirements. Herein, dual-network, multifunctional hydrogels (PSA/CS-GA) have been designed and synthesized through a one-pot approach. The in vitro and in vivo experiments demonstrate that the optimized hydrogels have exceptional antifouling properties, potent antibacterial effects and rapid hemostatic capabilities. Notably, in a full-thickness rat wound model, the hydrogel group displays a remarkable wound healing rate exceeding 95% on day 10, surpassing both the control group and the commercial 3M group. Furthermore, the hydrogels exert an anti-inflammatory effect by reducing inflammatory factors interleukin 6 (IL-6) and tumor necrosis factor-α (TNF-α), enhance the release of the vascular endothelial growth factor (VEGF) to promote blood vessel proliferation, and augment collagen deposition in the wound, thus effectively accelerating wound healing in vivo. These innovative hydrogels present a novel and highly effective approach to wound healing.

Innovative Acrylic Resin-Hydrogel Double-Layer Coating: Achieving Dual-Anchoring, Enhanced Adhesion, and Superior Anti-Biofouling Properties for Marine Applications

Traditional anti-corrosion and anti-fouling coatings struggle against the harsh marine environment. Our study tackled this by introducing a novel dual-layer hydrogel (A-H DL) coating system. This system combined a Cu2O-SiO2-acrylic resin primer for anchoring and controlled copper ion release with a dissipative double-network double-anchored hydrogel (DNDAH) boasting superior mechanical strength and anti-biofouling performance. An acrylamide monomer was copolymerized and cross-linked with a coupling agent to form the first irreversible network and first anchoring, providing the DNDAH coating with mechanical strength and structural stability. Alginate gel microspheres (AGMs) grafted with the same coupling agent formed the second reversible network and second anchoring, while coordinating with Cu2+ released from the primer to form a system buffering Cu2+ release, enabling long-term antibacterial protection and self-healing capabilities. FTIR, SEM, TEM, and elemental analyses confirmed the composition, morphology, and copper distribution within the A-H DL coating. A marine simulation experiment demonstrated exceptional stability and anti-fouling efficacy. This unique combination of features makes A-H DL a promising solution for diverse marine applications, from ship hulls to aquaculture equipment.

Innovative wound management: creating dynamic Alg-Mg/SF hydrogels for controlled Mg2+ release in wound healing

Antibacterial hydrogels have gained considerable attention for soft tissue repair, particularly in preventing infections associated with wound healing. However, developing an antibacterial hydrogel that simultaneously possesses excellent cell affinity and controlled release of metal ions remains challenging. This study introduces an antibacterial hydrogel based on alginate modified with bisphosphonate, forming a coordination complex with magnesium ions. The hydrogel, through an interpenetrating network with silk fibroin, effectively controls the release of magnesium ions and enhances strain resistance. The Alg-Mg/SF hydrogel not only demonstrates outstanding biocompatibility and broad-spectrum antibacterial properties but also stimulates macrophages to secrete anti-inflammatory factors. This advanced Alg-Mg/SF hydrogel provides a convenient therapeutic approach for chronic wound management, showcasing its potential applications in wound healing and other relevant biomedical fields.

Designing Composite Stimuli-Responsive Hydrogels for Wound Healing Applications: The State-of-the-Art and Recent Discoveries

Effective wound treatment has become one of the most important challenges for healthcare as it continues to be one of the leading causes of death worldwide. Therefore, wound care technologies significantly evolved in order to provide a holistic approach based on various designs of functional wound dressings. Among them, hydrogels have been widely used for wound treatment due to their biocompatibility and similarity to the extracellular matrix. The hydrogel formula offers the control of an optimal wound moisture level due to its ability to absorb excess fluid from the wound or release moisture as needed. Additionally, hydrogels can be successfully integrated with a plethora of biologically active components (e.g., nanoparticles, pharmaceuticals, natural extracts, peptides), thus enhancing the performance of resulting composite hydrogels in wound healing applications. In this review, the-state-of-the-art discoveries related to stimuli-responsive hydrogel-based dressings have been summarized, taking into account their antimicrobial, anti-inflammatory, antioxidant, and hemostatic properties, as well as other effects (e.g., re-epithelialization, vascularization, and restoration of the tissue) resulting from their use.

Recent advances in chitosan-based materials; The synthesis, modifications and biomedical applications

The attention to polymer-based biomaterials, for instance, chitosan and its derivatives, as well as the techniques for using them in numerous scientific domains, is continuously rising. Chitosan is a decomposable naturally occurring polymeric material that is mostly obtained from seafood waste. Because of its special ecofriendly, biocompatible, non- toxic nature as well as antimicrobial properties, chitosan-based materials have received a lot of interest in the field of biomedical applications. The reactivity of chitosan is mainly because of the amino and hydroxyl groups in its composition, which makes it further fascinating for various uses, including biosensing, textile finishing, antimicrobial wound dressing, tissue engineering, bioimaging, gene, DNA and drug delivery and as a coating material for medical implants. This study is an overview of the different types of chitosan-based materials which now a days have been fabricated by applying different techniques and modifications that include etherification, esterification, crosslinking, graft copolymerization and o-acetylation etc. for hydroxyl groups' processes and acetylation, quaternization, Schiff's base reaction, and grafting for amino groups' reactions. Furthermore, this overview summarizes the literature from recent years related to the important applications of chitosan-based materials (i.e., thin films, nanocomposites or nanoparticles, sponges and hydrogels) in different biomedical applications.

Functional Microneedle Patch for Wound Healing and Biological Diagnosis and Treatment

Wound healing, especially chronic wounds, has been one of the major challenges in the field of biomedicine. Drug therapy alone is not effective, so a variety of functional wound healing dressings have been developed. Microneedles have attracted more and more attentions in the field of wound healing dressings due to their penetration and high drug delivery efficiency. In this review, all the studies on the application of microneedles in wound healing in recent years are summarized, classify different microneedles according to their functions in the process of wound healing, discuss the current challenges in the transformation of microneedle technology toward clinical applications, and finally look forward to the future design and development directions of microneedles in this field.

Exploring the recent developments of alginate silk fibroin material for hydrogel wound dressing: A review

Hydrogels, a type of polymeric material capable of retaining water within a three-dimensional network, have demonstrated their potential in wound healing, surpassing traditional wound dressings. These hydrogels possess remarkable mechanical, chemical, and biological properties, making them suitable scaffolds for tissue regeneration. This article aims to emphasize the advantages of alginate, silk fibroin, and hydrogel-based wound dressings, specifically highlighting their crucial functions that accelerate the healing process of skin wounds. Noteworthy functions include self-healing ability, water solubility, anti-inflammatory properties, adhesion, antimicrobial properties, drug delivery, conductivity, and responsiveness to stimuli. Moreover, recent advancements in hydrogel technology have resulted in the development of wound dressings with enhanced features for monitoring wound progression, further augmenting their effectiveness. This review emphasizes the utilization of hydrogel membranes for treating excisional and incisional wounds, while exploring recent breakthroughs in hydrogel wound dressings, including nanoparticle composite hydrogels, stem cell hydrogel composites, and curcumin-hydrogel composites. Additionally, the review focuses on diverse synthesis procedures, designs, and potential applications of hydrogels in wound healing dressings.

Synergistic and Long-Lasting Wound Dressings Promote Multidrug-Resistant Staphylococcus Aureus-Infected Wound Healing

Background

Multidrug-resistant staphylococcus aureus infected wounds can lead to nonhealing, systemic infections, and even death. Although advanced dressings are effective in protecting, disinfecting, and maintaining moist microenvironments, they often have limitations such as single functionality, inadequate drug release, poor biosafety, or high rates of drug resistance.

Methods

Here, a novel wound dressing comprising glycyrrhizic acid (GA) and tryptophan-sorbitol carbon quantum dots (WS-CQDs) was developed, which exhibit synergistic and long-lasting antibacterial and anti-inflammatory effects. We investigated the characterization, mechanical properties, synergistic antibacterial effects, sustained-release properties, and cytotoxicity of GA/WS-CQDs hydrogels in vitro. Additionally, we performed transcriptome sequence analysis to elucidate the antibacterial mechanism. Furthermore, we evaluated the biosafety, anti-inflammatory effects, and wound healing ability of GA/WS-CQDs dressings using an in vivo mouse model of methicillin-resistant staphylococcus aureus (MRSA)-infected wounds.

Results

The prepared GA/WS-CQDs hydrogels demonstrated superior anti-MRSA effects compared to common antibiotics in vitro. Furthermore, the sustained release of WS-CQDs from GA/WS-CQDs hydrogels lasted for up to 60 h, with a cumulative release of exceeding 90%. The sustained-released WS-CQDs exhibited excellent anti-MRSA effects, with low drug resistance attributed to DNA damage and inhibition of bacterial biofilm formation. Notably, in vivo experiments showed that GA/WS-CQDs dressings reduced the expression of inflammatory factors (TNF-α, IL-1β, and IL-6) and significantly promoted the healing of MRSA-infected wounds with almost no systemic toxicity. Importantly, the dressings did not require replacement during the treatment process.

Conclusion

These findings emphasize the high suitability of GA/WS-CQDs dressings for MRSA-infected wound healing and their potential for clinical translation.

Poly(vinyl alcohol)/Pullulan Composite Hydrogels as a Potential Platform for Wound Dressing Applications

Hydrogels are 3D networks with an excellent ability to retain a high amount of water or biological fluids, representing suitable candidates for wound dressing applications. They can provide a protective barrier and a moist environment, facilitating wound treatment. The present paper focuses on physical hydrogels obtained from poly(vinyl alcohol) (PVA) and pullulan (PULL) mixtures in different weight ratios by using the freezing/thawing method. Hybrid hydrogels of similar polymer compositions were prepared in the presence of 0.5% Laponite^® RD. The influence of polysaccharide and clay addition on the properties of PVA hydrogels was investigated. Scanning electron microscopy showed evidence of the inner porous structure. The viscoelastic properties were investigated in different shear conditions and revealed the influence of the hydrogel composition on the network strength. The swelling behavior was followed in physiological saline solutions at 37 °C and pH = 7.4. For all samples, a quasi-Fickian diffusion mechanism was found. The delivery of neomycin sulfate was studied in similar conditions as for the swelling tests (0.15 M NaCl solutions; 37 °C; pH = 7.4) and different kinetic models were used to determine the release mechanism. The Peppas-Sahlin approach described very well the in vitro drug release mechanism from the polymeric hydrogels in the absence of clay. However, the hybrid polymer/clay hydrogels showed the best fit with the Korsmeyer-Peppas model. According to the present study, the porous membranes containing 40-60% PULL (in absence of clay) are suitable for the release of therapeutic agents at wound sites in physiological conditions.

Wound Gel with Antimicrobial Effects Based on Polyvinyl Alcohol and Functional Aryloxycyclotriphosphazene

A silver-containing gel based on polyvinyl alcohol and aryloxycyclotriphosphazene containing β-carboxyethenylphenoxy and p-formylphenoxy groups has been developed. Phosphazene was synthesized via the Doebner reaction from hexakis[(4-formyl)phenoxy]cyclotriphosphazene and malonic acid and characterized by ¹H, ¹³C, and ³¹P NMR spectroscopy and MALDI-TOF mass spectrometry. The study of the gel using scanning electron microscopy showed that the gel contains open pores and can absorb wound exudate. The maximum water absorption capacity of the gel was 272%, which was reached after 80 min of testing. The antimicrobial activity of the obtained silver-containing gel was evaluated using the diffusion method. The gel was found to inhibit the growth of the main microorganisms in contact with the skin: the bacteria S. aureus, P. aeruginosa, E. coli, B. subtilis, S. epidermidis, and C. stationis and the fungus C. albicans. The study of the wound-healing effect of the gel in vivo showed a decrease in the wound area of the rabbit hind limb by 91.43% (p < 0.05) on the 10th day of observation and a decrease in the content of C-reactive protein in the rabbit blood serum by 1.3 times (p < 0.05).