Bacterial Growth and Death on Cotton Fabrics Conformally Coated with ZnO Thin Films of Varying Thicknesses via Atomic Layer Deposition (ALD)

Abstract

Hospital fabrics are commonly exposed to multiple patients and contaminated surfaces between washing/sterilization cycles. Consequently, these textiles act as vectors for the spread of diseases, especially bacterial pathogens. Many modification schemes have been proposed to mitigate the growth and spread of bacteria on fabrics, including use of antimicrobial metal oxide nanoparticles. The aim of this study is to examine the effectiveness of conformal nanoscale ZnO coatings applied to cotton fabrics via atomic layer deposition to control bacterial spread. We find that, at low ZnO loading fractions, bacteria metabolize Zn2+ ions and reproduce more rapidly. However, as the ZnO loading is increased, the higher concentrations of Zn2+ overwhelm the bacteria and the nanocoatings become effective antibacterial treatments, killing all bacteria present. These results map out an important design space for implementing ZnO coatings as a potential antimicrobial treatment for textiles and other surfaces.