Helena P Felgueiras
University of Minho, Portugal
Title: Mechanically resistant, biodegradable PVA/CA dressings functionalized with LL37 peptide reduce microbial burden
Biography
Biography: Helena P Felgueiras
Abstract
Statement of the Problem: Typically, acute wound healing is a well-organized process that evolves in a predictable amount of time. Chronic wounds (CW) result from gradual tissue degradation, and are characterized by defective cell matrix, high bacteria counts, prolonged inflammation and moisture imbalance. Antimicrobial dressings, that combine dressing and antibiotics, have been suggested as potential strategies to treat CW. However, the rising of antibiotic-resistant pathogens has turned these systems obsolete, revealing antimicrobial-peptides (AMPs), which display a broad spectrum of activity against pathogens and act rapidly at multiple sites within microbial cells, as viable alternatives.
Methodology: In this work, poly (vinyl alcohol) (PVA) and cellulose-acetate (CA) were prepared via casting/phase-inversion method in the form of films. Different PVA/CA ratios were tested. Their mechanical, thermal and biodegradation profiles were followed. The films capacity to absorb exudates was also determined. Films were functionalized with LL-37 peptide. This AMP is endowed with immunoregulatory abilities, with great potential for wound healing, and important antimicrobial features.
Findings: Results revealed the homogeneity of the fashioned dressings, their thermal stability and mechanical resistance above skin, namely tensile strength. As the content of CA increased, the films absorbancy decreased. Dressing’s degradation was more important at basic pHs (i.e. simulated body fluid at pH 9). LL-37 was more efficient against Gram positive bacteria (i.e. Staphylococcus epidermidis) than Gram negative. In vitro, clotting time was significantly accelerated by this AMP presence in the dressings. Overall, the PVA/CA functionalized films demonstrated their potential for applications in wound healing.