Development of a Device for Dynamic Simulation of the Breathing System to Evaluate a Functional Nonwoven Fabric Coated with Cu Film

One of the challenges to evaluate the performance of functional materials for face masks is to look for a dynamic interaction with biological samples. A device for dynamic simulation of breathing system is constructed and dynamic and static responses of a polypropylene (C₃H₆)_n nonwoven fabric coated with Cu film by magnetron-sputtering process, against Escherichia coli, are analyzed. The use of scanning electron microscopy, energy-dispersive spectroscopy, and the 3-4,5-dimethylthiazol-2-yl)-2,5-diphenyltetrazolium bromide (MTT) indirect method using the L929 mouse fibroblasts, and the procedure of Antibacterial Activity of Textile Materials: Parallel Streak (TM147) from American Association of Textile Chemists and Colorists (AATCC) using E. coli and Staphylococcus aureus strains, allows to evaluate the morphological, physicochemical, and biological static performance of the obtained composite. No leaching of the deposited Cu film in the substrate is observed after using the device for dynamic simulation of breathing system. The permeability coefficient of the nonwoven fabric is obtained, equivalent to 71.4 Pa cm⁻². By the dynamic response against E. coli bacteria, the best bactericidal activity is observed for S960 with the maximum Cu concentration, presenting a high potential for application as a functional layer in facial masks.