Centrifugally spun and ZnO-infiltrated PVA fibers with antibacterial activity for treatment of Acne vulgaris.

The increasing spread of Acne vulgaris makes antibacterial agents increasingly important, especially for patients, who cannot use systemic antibacterial therapeutics. Recently, polymeric nano- and submicron-fibers with have attracted increasing interest in cosmetic and dermatological applications. Combined with the Vapor Phase Infiltration (VPI) process, the fibers serve as containers for the growth of metal oxides for a later use. We address the use of antibacterial agents by developing active antibacterial polymer-inorganic composites without any ZnO nanoparticles on the surface that are loose and would potentially detach. We fabricate poly(vinyl alcohol) fibers by centrifugal spinning and then infiltrate them with ZnO by applying 1 to 128 VPI cycles in the fluidized bed Atomic Layer Deposition reactor. The fibers´ morphology and structure is investigated by Scanning and Transmission Electron Microscopies and X-ray diffractometry. The presence of Zn and its uniform distribution on the surface is confirmed by scanning TEM Energy Dispersive X-ray spectroscopy. The prepared materials are subsequently tested for their antibacterial activity against Cutibacterium acnes and Staphylococcus epidermidis, main acne-causing bacteria. The results of antibacterial activity show that PVA fibers infiltrated with ZnO nanocrystals by >32 VPI cycles effectively inhibit growth of the acne-causing bacteria. Moreover, the homogeneous distribution of ZnO nanocrystals infiltrated within the fibers ensures the immediate release of Zn2+ while preserving the fibrous structure, in contrast to fibers with nanoparticles prepared directly from the spinning solution. Therefore, the study suggests that the PVA fibers infiltrated with ZnO exhibit promising potential as a material for anti-acne face masks.