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The addition of silver nanoparticles (AgNPs) to biomedical textiles can be of great interest to protect the materials against microorganisms and prevent their spread. However, the human and environmental over‐exposure to AgNPs is leading to numerous concerns due to their toxicity. In this work, AgNPs were stabilized onto polyamide 6.6 fabrics (PA66) through atmospheric dielectric barrier discharge (DBD) plasma treatment and the use of chitosan (Ch) layers applied by spray. DBD plasma treatment revealed a crucial role in AgNPs adhesion (4.8 and 6.3 At%). A first layer of Ch decreased the AgNPs adhesion in both untreated and DBD plasma‐treated samples but treated samples show higher concentration (1.7 and 4.1 At%). The antibacterial activity was evaluated against Staphylococcus aureus and Escherichia coli after 2 and 24 h, showing a superior action in all samples with DBD plasma treatment after 24 h. The Ch in the first layers of the composites delayed the antimicrobial action of the samples but it also may enhance antimicrobial action. The obtained coatings will allow the development of novel and safe wound dressings with improved AgNPs deposition, controlled ions released and consequently, manage the antimicrobial performance and minimize the AgNPs side effects.

info:eu-repo/semantics/publishedVersion

Healthcare-associated infections (HCAI) are complications of healthcare that result in elevated patient morbidity and mortality. HCAI present a huge financial burden for patients, hospitals and insurers due to extended hospitalisation and associated care. According to the estimations, in the US alone, HCAI affects approximately 2 million patients annually, of whom approximately 90.000 patients die, with an estimated annual cost estimated to range from 28 billion to 45 billion US$. [1] European Union is facing the similar situation, the European Centre for Disease Prevention and control (ECDC) advice that approximately 4.1 million acute care patients acquire a HCAI annually, with 37.000 deaths directly attributed to HCAI. With increasing prevalence of HCAI across European countries and threatening development of antimicrobial resistance to widely used antibiotics, there is a recognised need for novel approach in battle against this healthcare burden [2]. One of the approaches involves a development and fabrication of materials with antimicrobial properties. Usually, these are coatings with integrated antibacterial agent that is responsible for the elimination of microorganisms that come into contact with active surface. There is a variety of different antibacterial compounds integrated in such coatings, such as different antibiotics, chemical compounds, peptides. Recently, metal nanoparticles (NPs) have been increasingly used in designing coatings with antibacterial properties due to their large surface-to-volume ration, physiochemical properties and biological multi-target mechanism of actions. Besides all beneficial properties of NPs their emergence of cytotoxicity is limiting their practical applications in human body. [3-4] To overcome this drawback it is important to design a new class of antibacterial coatings with firmly embedded NPs that allows controlled release of antimicrobial agent into the microenvironment. Atmospheric pressure plasma technology has shown a big promise as an alternative and cost-efficient method for deposition of coatings with antibacterial properties. This contribution explores the potential of plasma-assisted approach for fabrication of antibacterial coatings, containing different metal NPs on medical textiles. Plasma-assisted deposition of coatings was carried out with so-called ˝sandwich technique˝, where nanoparticles were embedded between two layers in order to tailor the desirable ion release and to prolong antibacterial effect of fabrics. Antibacterial effects of different nano-coatings were tested against G+ and G- bacterial species, Staphylococcus aureus and Escherichia coli, respectively. Besides antibacterial properties, potential cytotoxic effects were also studied. The study demonstrates that atmospheric pressure plasma can be an efficient technique for deposition of antibacterial coatings containing metal NPs. Medical textiles with plasma-assisted nano-coatings showed effective antibacterial properties. The choice of proper metal antimicrobial agent and optimal concentration of NPs should be considered in regards to potential cytotoxic effects when these materials would be used in medical environments., info:eu-repo/semantics/publishedVersion

Non-woven textile materials with antimicrobial properties are of high demands for applications ranging from medical dressing to everyday cleaning products. We proposed plasma assisted route to engineer polymer films and non-woven fabrics with antimicrobial nano-composite coatings. Atmospheric pressure plasma is used for deposition of nano-composites. Nano-particles Ag, Cu and ZnO are tested as antimicrobial agents with average nano-particles size of about 50 nm. Nanoparticles are incorporated in between two layers of organosilicon film with impregnation process or alternatively through aerosol injection step. Incorporation is made in “sandwich-like structure” where top layer coating (barrier) of 5 - 50 nm thickness is used for precise control of metal ions release and reservation layer of about 200 nm is used for NPs load. The effect of the barrier coating on surface concentration of nano-particles is determined with XPS method. It is shown that increase of the thickness of the barrier layer from 5 to 25 nm leads to decrease of Ag content from 0.24 to 0.08 at. %. Similar effect is found for nano-particles of Cu and ZnO. Antibacterial efficiency of the samples against P. aeruginosa ATCC 9027 and S. aureus M u50 bacteria shows that all treated samples exhibit higher antibacterial efficiency against S. aureus. The antibacterial efficiency of AgNPs and CuNPs is above 90% which is practically interested for medical application while ZnONPs shows lower antibacterial efficiency. Cytotoxicity of the coatings and materials is investigated for different deposition conditions and analyzed in terms of possible medical applications., M.Era-Net project “PlasmaTex”, info:eu-repo/semantics/publishedVersion