Multifunctional Enzymatically Generated Hydrogels for Chronic Wound Application

Abstract

The healing of chronic wounds requires intensive medical intervention at huge healthcare costs. Dressing materials should consider the multifactorial nature of these wounds comprising deleterious proteolytic and oxidative enzymes and high bacterial load. In this work, multifunctional hydrogels for chronic wound application were produced by enzymatic cross-linking of thiolated chitosan and gallic acid. The hydrogels combine several beneficial to wound healing properties, controlling the matrix metalloproteinases (MMPs) and myeloperoxidase (MPO) activities, oxidative stress, and bacterial contamination. In vitro studies revealed above 90% antioxidant activity, and MPO and collagenase inhibition by up to 98 and 23%, respectively. Ex vivo studies with venous leg ulcer exudates confirmed the inhibitory capacity of the dressings against MPO and MMPs. Additionally, the hydrogels reduced the population of the most frequently encountered in nonhealing wounds bacterial strains. The stable at physiological conditions and resistant to lysozyme degradation hydrogels showed high biocompatibility with human skin fibroblasts.

Thiolation of Chitosan Loaded over Super-Magnetic Halloysite Nanotubes for Enhanced Laccase Immobilization

“…This led to a significant enhancement of laccase loading over the HNTs-Fe3O4-CTs-SH. A similar mechanism of the laccase immobilization over the (-SH) modified supports was reported earlier [19,7,33,34].…”

Achieving Controlled Biomolecule–Biomaterial Conjugation

“…Alternatively, the oxidizing enzyme laccase offers possibilities for peptide and protein conjugation in the absence of added peroxide, due to its ability to utilize atmospheric oxygen to undertake phenol oxidation, generating water as the only byproduct. 320 Finally, a large number of reagents able to mimic the activity of HRP have been developed, which avoid the potential limitations of enzyme instability and environmental sensitivity. Many such systems exploit metal complexes able to oxidize organic substrates in the presence of hydrogen peroxide.…”

The Role of Antioxidants on Wound Healing: A Review of the Current Evidence

“…Gallic acid belongs to a group of natural polyphenol compounds found in almost all plants, including fruits, leaves, and wildflowers. It has gained significant attention for its biological effects, such as its antioxidant, anti-inflammatory, and analgesic properties [26,27].…”