Distinct antimicrobial analysis to evaluate multi-component wound dressing performance

Abstract

Wound infection hinders adequate healing, being particularly grievous and prevalent in burn wounds and chronic wounds. Wound infection extends inflammation, preventing epithelialization and angiogenesis. Therefore, infection prolongs healing time, steeply increases treatment costs and degrades patients wellbeing. One successful strategy to control wound infection is to apply an active wound dressing, able to eliminate or significantly reduce the microbial population present at the infection site. Silver nanoparticles (AgNPs) are a multipurpose antimicrobial agent with a wide scope of applications which include wound dressings. Nevertheless, several studies denote AgNPs dose-dependent cytotoxicity, and their capability to bypass the blood-brain barrier and induce a neurotoxic effect. Hence, we propose to adopt two different strategies to attempt the simultaneously immobilize and increase the load of AgNPs within the wound dressing fabric. Thus, the envisaged objective is to prevent potential systemic cytotoxicity /through immobilization and to improve its antimicrobial capability due to the higher concentration of AgNPs. Two different approaches were used: i. AgNPs were suspended in an alginate (ALG) solution, ii. AgNPs were embedded in Mordenite (MOR) zeolite, followed by the addition of an ALG solution. Both suspensions were incorporated into polyester fabric assisted by its surface activation by dielectric barrier discharge (DBD) plasma treatment. The bactericidal and virucidal effectiveness of each composite was tested against bacteria species known to induce nosocomial infections and a bacteriophage that is a potential surrogate of severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2). Two distinct antimicrobial analyses were used to provide insights on the antimicrobial effectiveness of the obtained composites and to indirectly assess the release of AgNPs.