Deposition of thin metal layers on chitosan films

The presented work is focused on preparation of chitosan films which were modified by plasma treatment and sputtering of silver nanoparticles (AgNPs) which made silver layers. The films were doped with AgNPs for enhancement of antibacterial properties. The presence of AgNPs was studied by X-ray photoelectron spectroscopy. Wettability and surface morphology of the films were evaluated. Antibacterial activity of solid films with AgNPs was tested by drip test on two bacterial strains, Gram-positive Staphylococcus epidermidis and Gram-negative Escherichia coli. The films exhibited strong antibacterial activity against both bacterial strains. Solid films were dissolved and analyzed by transmission electron microscopy. Concentration of the AgNPs released into the solution during dissolution was studied by atomic absorption spectroscopy. The presence of AgNPs was confirmed both in the solid films and in the solutions by the above mentioned methods. Our research was aiming on use of these films in medicine as a new type of wound dressing with antibacterial properties.