Omniphobic ZIF‐8@Hydrogel Membrane by Microfluidic‐Emulsion‐Templating Method for Wound Healing

Abstract

Bacterial adhesion and colonization can result in chronic non‐healing wounds. Current hydrophilic wound dressings can release antibacterial agents into the wound exudate, but may result in overhydrated wounds, bacterial overgrowth, and even tissue maceration. Hydrophobic dressings are anti‐fouling, though ineffective to encapsulate and release bactericidal agents. Combining the advantages of hydrophilic and hydrophobic dressings seems difficult, until the development of superwettability surfaces offers an opportunity for omniphobic dressings from intrinsic hydrophilic polymers. Herein, omniphobic porous hydrogel wound dressings loaded with a zinc imidazolate framework 8 (ZIF‐8) are fabricated by a microfluidic‐emulsion‐templating method. The fabricated porous hydrogel membrane with its reentrant architecture is repellent to blood and body fluids, though intrinsically hydrophilic. This unique combination not only reduces the adhesion of harmful microbes, but also enables the encapsulation and release of antibacterial ingredients to wounded sites from hydrophilic polymer networks. As such, the omniphobic metal‐organic frameworks (MOFs)@hydrogel porous wound dressing can inhibit bacteria invasion and enable the controlled release of the bactericidal, anti‐inflammatory, and nontoxic zinc ions. Furthermore, in vivo study of infected full‐thickness skin defect models demonstrates that the dressing also accelerates wound closure by promoting angiogenesis and collagen deposition. Therefore, the omniphobic MOFs@hydrogel porous wound dressings are potentially useful for clinical application.

Surface Engineered Metal-Organic Frameworks (MOFs) Based Novel Hybrid Systems for Effective Wound Healing: A Review of Recent Developments

“…Wound dressings are preferred for protecting wounds from bacterial colonization and other environmental hazards. Distinct wound dressings were required to fight bacteria by embedding bactericidal ingredients like polymeric substances and metal ions (Yao et al, 2020). The dressings are also made from inherent hydrophilic fabrics, like cotton, polymers, and hydrogels, to promote the infiltration of released active ingredients into wounds (Dhivya et al, 2015).…”

“…Being intrinsically bactericidal, further surface modification of MOFs can synergistically improve their wound healing activity. Furthermore, they can also be loaded with therapeutic substances and release them in a programmable manner, thus leading to effective wound healing with higher safety (Xiao et al, 2017;Yao et al, 2020). Most recently, Yao et al reported the fabrication of omniphobic MOFs based hydrogel porous wound dressing for inhibition of bacteria invasion and acceleration of wound healing.…”

“…The novel MOFs based hydrogel showed a controlled release of the non-toxic zinc ions anti-inflammatory and bactericidal. Besides, the wound dressing relying on MOFs has speeded up the wound healing in an infected full-thickness skin defect model due to angiogenesis, synergistic antibacterial effects, reduced inflammation, the proliferation of fibroblasts and collagen deposition (Yao et al, 2020). In another most recent study, Han et al (2020) synthesized photosensitive wound dressing hydrogels using MOFs modified with double-bond modified chitosan, Prussian blue, and quaternary ammonium.…”

“…Being intrinsically bactericidal, further surface modification of MOFs can synergistically improve their wound healing activity. Furthermore, they can also be loaded with therapeutic substances and release them in a programmable manner, thus leading to effective wound healing with higher safety ( Xiao et al, 2017 ; Yao et al, 2020 ).…”

“…Furthermore, certain elements used as structural blocks of MOFs, for instance, zinc and copper, help in wound healing of infectious wounds of S. aureus and E. coli due to their natural bactericidal properties, thus leading to effective and rapid wound healing. Similarly, MOF-based wound dressing accelerates wound healing due to its bactericidal and anti-inflammatory properties through encouraging cell proliferation, angiogenesis, and collagen deposition ( Hinks et al, 2010 ; Rubin et al, 2018 ; Hou and Tang, 2019 ; Kargozar et al, 2019a ; Yao et al, 2020 ). Interestingly, MOFs have free functional groups decorated on their surfaces, thus they provide opportunities for their surface functionalization.…”