Atmospheric plasma immobilization of antimicrobial Zeolite loaded silver nanoparticles on medical textiles

Abstract

1. Introduction Nosocomial infections, in particular problematic chronic wounds, are a ubiquitous general concern. This apprehension was acuted by the prevalence of multidrug resistant bacteria and emergence of Pandemics. Therefore, the development of novel and highly effective antimicrobial wound dressing comprising marginal or absent cytotoxicity to the patient is crucial. Plasma plays a key role in improving the functionalization of surfaces, in particular of textiles [1]. Thus, in this work we used atmospheric double dielectric discharge (DBD) plasma activated woven polyester (PES) functionalized with silver nanoparticles (AgNPs), enzymes as antimicrobial agents, immobilized using mordenite (MOR) zeolites and polysaccharide-based matrixes to mitigate cytotoxicity.

2. Methodology and results MOR was used with the objective of improving the concentration, stability, and immobilization efficiency of AgNPs and enzymes in the functionalized fabric. Therefore, a solution combining the AgNPs, and/or antimicrobial enzymes was prepared. Afterwards, this solution was mixed with a polysaccharide matrix, consisting of alginate or chitosan. Woven PES surface was activated using DBD and was impregnated with the prepared formulation. The antimicrobial activity of the functionalized fabrics was characterized using bacteria commonly associated to nosocomial infections as well as a virus that is a potential surrogate of severe acute respiratory coronavirus 2 (SARS-COV-2). The antimicrobial tests performed comprised the evaluation of antimicrobial efficacy when in contact with the composites during 1 to 2 hours, by adapting the following standards: AATCC TM100-100 and ISO18184. The microorganisms used were S. aureus, E. coli, and bacteriophage MS2. The formulated composites containing alginate as matrix displayed a high antibacterial activity (higher than 99.999 %) which was stable for over than 15 days of storage. However, it did not exhibit any antiviral activity. The alginate composites also did not hinder the activity of protease, which may have an important antifouling activity. Whereas, the composites containing chitosan exhibited a highly effective antimicrobial activity against the bacteria and the virus (higher than 99.9999 %) when zeolite was present in the formulation.