Bilayer Hydrogels for Wound Dressing and Tissue Engineering

Abstract

A large number of different skin diseases such as hits, acute, and chronic wounds dictate the search for alternative and effective treatment options. The wound healing process requires a complex approach, the key step of which is the choice of a dressing with controlled properties. Hydrogel-based scaffolds can serve as a unique class of wound dressings. Presented on the commercial market, hydrogel wound dressings are not found among proposals for specific cases and have a number of disadvantages—toxicity, allergenicity, and mechanical instability. Bilayer dressings are attracting great attention, which can be combined with multifunctional properties, high criteria for an ideal wound dressing (antimicrobial properties, adhesion and hemostasis, anti-inflammatory and antioxidant effects), drug delivery, self-healing, stimulus manifestation, and conductivity, depending on the preparation and purpose. In addition, advances in stem cell biology and biomaterials have enabled the design of hydrogel materials for skin tissue engineering. To improve the heterogeneity of the cell environment, it is possible to use two-layer functional gradient hydrogels. This review summarizes the methods and application advantages of bilayer dressings in wound treatment and skin tissue regeneration. Bilayered hydrogels based on natural as well as synthetic polymers are presented. The results of the in vitro and in vivo experiments and drug release are also discussed.

Functional drug-delivery hydrogels for oral and maxillofacial wound healing

“…In addition, the oral mucosa is in direct contact with the external environment and is prone to inflammation and oxidation, and prolonged inflammation that is difficult to suppress may lead to tissue necrosis and reduced function of the oral and maxillofacial area ( Senel, 2021 ; Ngeow et al, 2022 ). The anti-inflammatory and antioxidant properties of hydrogels help to alleviate oxidative stress and reduce the inflammatory response ( Luneva et al, 2022 ). Bacteria in the oral cavity can become pathogenic when the body is compromised or immunocompromised, causing slow wound healing.…”

Nanomaterials in the Wound Healing Process: New Insights and Advancements

“…The modern advantages of hydrogel-based dressings are their antibacterial, surface adhesion, hemostasis, anti-inflammatory, antioxidant, target delivery, self-healing, stimuli-responsive, and wound diagnostic features [ 120 ]. Bilayer hydrogels have shown tremendous applicability, especially in wound healing action [ 121 , 122 ]. In fact, a few compounds, such as hyaluronic acid, have demonstrated excellent flexibility in the pharmaceutical industry owing to their gel-based nature [ 123 ].…”

Fabrication and Performance Evaluation of Gelatin/Sodium Alginate Hydrogel-Based Macrophage and MSC Cell-Encapsulated Paracrine System with Potential Application in Wound Healing

“…Loading bFGF into hydrogels was proved to be another efficient approach for combating wound healing, in the aspect of enhanced dermis and granulation tissue growth and blood vessel formation [ 7 ]. Yet, this strategy displayed drawbacks of limited regulation capability of growth factor and denaturation of bioactive components [ 8 , 9 , 10 ]. Consequently, novel therapeutic systems were still on high demand.…”