| AVS 63rd International Symposium & Exhibition | |
| Plasma Processing for Biomedical Applications Focus Topic | Monday Sessions |
| Session PB+BI+PS-MoA |
| Session: | Plasma Processing of Biomaterials |
| Presenter: | Uroš Cvelbar, Jozef Stefan Institute, Slovenia |
| Authors: | A. Nikiforov, Ghent University, Belgium I. Kuchakova, Ghent University, Belgium T. Coenye, Ghent University, Belgium C. Leys, Ghent University, Belgium N. Hojnik, Jozef Stefan Institute, Slovenia M. Modic, Jozef Stefan Institute, Slovenia U. Cvelbar, Jozef Stefan Institute, Slovenia |
| Correspondent: | Click to Email |
In this work, the antimicrobial non-woven fabrics were prepared with the use of atmospheric pressure plasma deposition.Atmospheric pressure DC jet operating in N2 at current density of 6 mA/cm2 and voltage of 15 kV is used as a source of non-thermal plasma for engineering of the antibacterial nano-composites on surface of polymeric polyethylene terephthalate (PET) meshes. Nano-particles of Ag, Cu and ZnO are tested as antimicrobial agents through incorporation in to the structure of the plasma deposited composite film. The deposition process is carried out in three steps process. The fabric is first pretreated by depositing a first layer (250 nm - 500 nm) of organosilicon thin film using an atmospheric pressure plasma system, then nano-particles are incorporated by a dipping-dry, and finally the nano-particles are covered by a second organosilicon layer of 10-50 nm thickness. Top layer in the composite coating of “sandwich-like structure” with variable thickness is used for precise control of metal ions release and so to tune antimicrobial efficiency of the material. The deposition process and surface chemistry of the coatings are studied by emission spectroscopy, and surface analysis techniques: XPS, AFM and SEM. The antimicrobial activity of the treated fabrics is also tested against Pseudomonas aeruginosa and Staphylococcus aureus. It is revealed that thickness of top (barrier) layer plays a key role in release of metal ions and negligible small antibacterial activity is observed if barrier thickness exceeds 50 nm. Tests with S. aureus show that the highest 98% bacterial reduction is achieved with Cu NPs whereas Ag NPs are much less effective and can provide only 79% reduction. In contrast, the fabric antibacterial efficiency against of Pseudomonas aeruginosa is very low for both Cu and ZnO nanoparticles in spite of the load and only Ag NPs are proved to be effective (2 orders reduction) against of P. Aeruginosa. The results clearly indicate that plasma of atmospheric pressure can be used as effective tool for immobilization of nano-particles in composite coatings. Control of antibacterial activity can be achieved through variation of deposition parameters and a type of incorporate nanoparticles. The approach might present a new route to preparation of effective antimicrobial materials against of certain class of bacteria.
This work is partially supported by the M.Era-Net project “PlasmaTex”.