Recent Advances in Biodegradable and Biocompatible Synthetic Polymers Used in Skin Wound Healing

Abstract

The treatment of skin wounds caused by trauma and pathophysiological disorders has been a growing healthcare challenge, posing a great economic burden worldwide. The use of appropriate wound dressings can help to facilitate the repair and healing rate of defective skin. Natural polymer biomaterials such as collagen and hyaluronic acid with excellent biocompatibility have been shown to promote wound healing and the restoration of skin. However, the low mechanical properties and fast degradation rate have limited their applications. Skin wound dressings based on biodegradable and biocompatible synthetic polymers can not only overcome the shortcomings of natural polymer biomaterials but also possess favorable properties for applications in the treatment of skin wounds. Herein, we listed several biodegradable and biocompatible synthetic polymers used as wound dressing materials, such as PVA, PCL, PLA, PLGA, PU, and PEO/PEG, focusing on their composition, fabrication techniques, and functions promoting wound healing. Additionally, the future development prospects of synthetic biodegradable polymer-based wound dressings are put forward. Our review aims to provide new insights for the further development of wound dressings using synthetic biodegradable polymers.

Keywords: biocompatible; biodegradable; fabrication; skin wound healing; synthetic polymer.

Figure 1

Fabrication techniques for the construction of skin scaffolds.

Figure 2

The chemical structures of PVA, PCL, PLA, PLGA, PU, and PEO/PEG.

Figure 3

Combination of PVA and natural polymers as well as other add-ons for the construction of skin tissue engineering scaffolds. (A) PVA and SA were crosslinked by GA to establish a sponge that swells at the wound in response to hemostasis and prevents excessive blood absorption after thrombosis. Reprinted with permission from Ref. [73]. 2022, Elsevier. (B) PVA–CS sponge acts to promote hemostasis by attracting negatively charged blood cells and exerting pressure on bleeding vessels. Reprinted with permission from Ref. [74]. 2019, Royal society of chemistry. (C) Nanofiber mats containing PVA, CS, and SF were fabricated by electrospinning and applied to a rat full thickness wound model after inoculation of bone marrow MSCs which significantly promoted wound healing [75]. (D) Hybrid hydrogels composed of Ag-loaded nanoparticles and TA-modified CNF with PVA and SA were used to treat wounds in rat wound models by anti-infection. Reprinted with permission from Ref. [77]. 2021, Elsevier. Reproduced with permission [73,74,75,77]. Abbreviations: PVA—polyvinyl alcohol; SA—sodium alginate; GA—glutaraldehyde; RBC—red blood cell; CS—chitosan; SF—silk fiber; MSCs—mesenchymal stem cells; TA—tannic acid; CNF—cellulose nanofibrils.

Figure 4

Examples of polymeric constructs for skin tissue engineering scaffolds. (A) Double-layer scaffold for wound healing by solvent casting of PU and EEP as an outer dense membrane while electrospun PCL and gelatin nanofibres served as an inner membrane [102]. (B) A sandwich-structured wound dressing with Janus membrane property was fabricated by using hydrophilic zinc silicate bioceramics and hydrophobic PLA which showed exudate absorption property and promoted hair follicle regeneration and wound healing through the release of Zn²⁺ and SiO3²⁻ ions [103]. (C) The combination of a 3D printed outer membrane made of PLGA nanofibers and an inner membrane composed of dECM nanofibers was employed to inhibit the formation of scar tissues. Reprinted with permission from Ref. [104]. 2022, copyright owner’s name. (D) Reactive liquid molding of isocyanates and PTK diols produces PTK-UR foams with tunable properties and interconnected pores suitable for cell infiltration and the repair of skin wounds. Reprinted with permission from Ref. [105]. 2022, American association for the advancement of science. (E) Insoluble copolymer A mixed with water-soluble copolymer B self-assembles into micelles, forming an in situ thermogel with a percolated micelle network upon heating; the TPN-loaded polymer solution forms an in situ hydrogel for wound treatment. Reprinted with permission from Ref. [106]. 2019, Springer. Reproduced with permission [102,103,104,105,106]. Abbreviations: PU—polyurethanes; EEP—ethanolic extract of propolis; PCL—polycaprolactone; THF—tetrahydrofuran; DMF—dimethylformamide; Gel—gelatin; TFE—2,2,2-trifluoroethanol; dECM—decellularized extracellular matrix; BLM—bilayer membranous; PTK—polythioketal; UR—urethane; ROS—reactive oxygen species; EG—ethylene glycol; TPN—teicoplanin; PLGA—Poly(lactic-co-glycolic acid); PEG—polyethylene glycol.