Polymeric Coatings Deposited from Propane–Butane Mixture in Atmospheric Pressure Surface DBD for Protection of Bacterial Colonization

Antibacterial coatings on biomedical instruments are highly valuable as they can prevent bacterial colonization on these devices. In this contribution, we deposited antibacterial polymeric thin coatings onto Teflon substrates using atmospheric pressure plasma polymerization from a propane–butane mixture. This process utilized surface dielectric barrier discharge in nitrogen at atmospheric pressure. We analyzed the chemical composition of the plasma polymerized propane–butane films using energy-dispersive X-ray spectroscopy (EDX) and Fourier-transform infrared spectroscopy (FTIR). The film surface properties were examined through scanning electron microscopy (SEM) and surface energy measurements. EDX analysis revealed that the films contained carbon, nitrogen, and oxygen from the surrounding air. FTIR analysis identified the presence of alkyl, nitrile, acetylene, imide, and amine groups. The films were hydrophilic, with water contact angles ranging from 13° to 23°. The thin film-coated samples demonstrated significant antibacterial activity against both S. aureus and E. coli strains. Furthermore, the films were cytocompatible, maintaining over 80% cell viability compared to reference polystyrene tissue. We also analyzed the deposition process in order to find the compounds responsible for antibacterial properties.