Multifunctional Antimicrobial Nanofiber Dressings Containing ε-Polylysine for the Eradication of Bacterial Bioburden and Promotion of Wound Healing in Critically Colonized Wounds

Abstract

Bacterial colonization of acute and chronic wounds is often associated with delayed wound healing and prolonged hospitalization. The rise of multi-drug resistant bacteria and the poor biocompatibility of topical antimicrobials warrant safe and effective antimicrobials. Antimicrobial agents that target microbial membranes without interfering with the mammalian cell proliferation and migration hold great promise in the treatment of traumatic wounds. This article reports the utility of superhydrophilic electrospun gelatin nanofiber dressings (NFDs) containing a broad-spectrum antimicrobial polymer, ε-polylysine (εPL), crosslinked by polydopamine (pDA) for treating second-degree burns. In a porcine model of partial thickness burns, NFDs promoted wound closure and reduced hypertrophic scarring compared to untreated burns. Analysis of NFDs in contact with the burns indicated that the dressings trap early colonizers and elicit bactericidal activity, thus creating a sterile wound bed for fibroblasts migration and re-epithelialization. In support of these observations, in porcine models of Pseudomonas aeruginosa and Staphylococcus aureus colonized partial thickness burns, NFDs decreased bacterial bioburden and promoted wound closure and re-epithelialization. NFDs displayed superior clinical outcome than standard-of-care silver dressings. The excellent biocompatibility and antimicrobial efficacy of the newly developed dressings in pre-clinical models demonstrate its potential for clinical use to manage infected wounds without compromising tissue regeneration.

Pearl Powder—An Emerging Material for Biomedical Applications: A Review

“…Some fibroblasts would differentiate to myofibroblasts and together they produce the collagen extracellular matrix (ECM) in the third maturation stage [ 10 , 41 ]. Wound healing can be affected by hypoxia, bacterial infection, poor local blood supply, age, and comorbidities such as diabetes [ 42 , 43 , 44 ]. Unfortunately, there are very few therapeutic agents available for stimulating wound healing.…”

“…The advancement of antimicrobial nanofibre dressings that provide protection to the injured tissues from commensal pathogens while promoting tissue regeneration at the same time would be significant in plastic and reconstructive surgery practices. Recently, Mayandi et al studied the effect of chondroitin sulphate on the physicochemical properties of polydopamine crosslinked electrospun gelatin nanofibres containing mineralized magnesium [ 44 ]. Composite dressings comprising polycaprolactone (PCL) and gelatin were also prepared to lengthen the durability of the dressings.…”

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“…In vivo imaging studies confirm that ePL-treated corneas appeared transparent and non-edematous compared to untreated infected corneas. Taken together these observations suggest that ePL can be potentially used as an antimicrobial agent for treating topical infections [21,39].…”

“…The wound closure was similar to standard of care silver dressings. In addition, the antibiotics-loaded dressings can be readily detached from wound sites thus displaying non-adherent nature [21]. This prototype wound dressings offers a potentially valuable approach for treating life-threatening burn injuries and burn-related infections.…”

“…This thesis addresses the utility of superhydrophilic electrospun gelatin nanofiber dressings (NFDs) containing a broad-spectrum antimicrobial polymer, εpolylysine (εPL), crosslinked by polydopamine (pDA) for treating second-degree burns [21]. The thesis is structured into 9 chapters as detailed below:…”