Inactivation of Hand Hygiene-Related Pathogens Using Engineered Water Nanostructures

Hand hygiene is a critical public health issue associated with disease transmission worldwide. Here, a nanotechnology-based approach has been employed to enhance hand hygiene using engineered water nanostructures (EWNS) synthesized by electrospray and ionization of antimicrobial aqueous solutions. The EWNS possess unique properties: have a tunable size in the nanoscale, are electrically charged, which results in a lifespan of hours in room conditions, and can carry both antimicrobial agents and reactive oxygen species (ROS) from ionization of water. More importantly, EWNS are highly mobile, can be directed toward a surface of interest utilizing their electric charge, and can inactivate pathogens by delivering active ingredients (AIs) and ROS. In this study, a variety of AIs commonly used for hand sanitization and food safety, such as hydrogen peroxide, citric acid, lysozyme, and nisin, were utilized to synthesize various EWNS-based nanosanitizers and inactivate hand hygiene-related pathogens. A 0.5 min exposure to various EWNS-based nanosanitizers reduced Escherichia coli, Staphylococcus aureus, and bacteriophage MS2 by similar to 3, 1, and 2 log, respectively. More importantly, such an aerosol-based nanocarrier platform, because of its targeted delivery manner, utilizes only nanograms of "nature-inspired" antimicrobials and leaves behind no chemical byproducts, making it an efficient approach for hand sanitization.