AquaROS: A Powerful New Disinfectant

Researchers at Stanford have developed a new water-based disinfectant with the potential to destroy a wide variety of pathogens and significantly improve healthcare settings. AquaROS, a novel and broad-spectrum disinfectant, is based on the formation of micron-sized water droplets that cause the spontaneous generation of highly reactive oxidant species (ROS). Access to safe and effective disinfecting solutions like AquaROS is more critical than ever – in the U.S. approximately the same number of people die from healthcare-associated infections (HAIs) as from AIDS, breast cancer and auto accidents combined. Inexpensively produced by atomizing water, the new disinfectant has been shown to outperform other commercial methods at inactivating Salmonella typhimurium and E. coli. Based on these and other promising results, the researchers anticipate AquaROS can kill bacteria, fungi, mycobacteria and bacterial spores on critical surfaces such as medical instruments.

Schematic of the generation of AquaROS from pure water with no chemicals added and no electricity applied. (Zare Lab)

Ongoing Research
The researchers are currently working on evaluating AquaROS for the inactivation of viruses with the goal of determining its effectiveness against SARS-CoV-2. They are further exploring the optimization of the disinfection by studying the effects of environmental parameters (i.e., humidity, temperature) on the effectiveness of the spray in killing pathogens. They are also working on modifying the spray design to eliminate the need for a nebulizing gas.

Stage of Development
AquaROS has been shown to be more efficient at destroying Salmonella typhimurium and E. coli compared to standard 3% hydrogen peroxide, a widely used commercial disinfectant. Preliminary results suggest that the droplets can eliminate bacteria by rupturing the cell membrane through oxidative stress and disruption by exposure to the droplets' magnetic field. The researchers' QRB Discovery paper [in press] describes the proof of principle of AquaROS for the disinfection of bacteria using two model bacteria, E. coli and S. typhimurium.