Introduction: Various lung disease including pneumonia, tuberculosis, lung Abscess, and bronchitis are caused by disinfection of pathogens, including contagious bacteria, viruses, fungi, and protozoa. We reported that water molecules are transformed into reactive oxygen species (ROS), including hydrogen peroxide (H2O2), superoxide (O2-), and hydroxyl radicals (OH·).1-4 These ROS have been shown to be effective in disinfecting pathogens and preventing the spreading of pathogens, especially antibiotic-resistant bacteria and viruses. Atomization of pure bulk water into micron or nanoscale droplets results in the spontaneous oxidation of water molecules in the microdroplets,3 creating electrochemically active water molecules. We demonstrate the effectiveness of the AquaROS for disinfecting bacteria by applying it to bacteria disinfection including E. coli and Salmonella cultured on surfaces.4 The addition of trace mount of surfactant increases the production of ROS and enhances the effectiveness of the microdroplet ROS for disinfection. We show that these ROS generated from water microdroplets are effect for the treatments of lung infection disease.
Materials and
Methods: We cultured E. coli and Salmonella bacteria on different surfaces including agar gel, stainless steel, plastic, and spinach leaf. ROS was generated by atomizing pure water (HPLC grade) into micro- or nanoscale droplets. The quantitative measurement of disinfecting power was conducted by two methods including dual staining with propidium iodide and SYTO9 as well as counting colony-forming units.
Results, Conclusions, and Discussions: The dual staining of AquaROS treated bacteria with propidium iodide and SYTO9 showed that it is capable of killing over 99.99% E. coli and Salmonella. Mass spectrometric and TEM analyses were carried out that the destruction of the bacterial membrane is the primary cause of bacterial inactivation by the microdroplet ROS. The ROS production was enhanced when a trace amount of metal or organic surfactants was used. Our studies conducted on different surfaces, including stainless steel, plastic surface, and spinach leaf show that AquaROS has the potential to be an effective disinfectant for hospital settings, medical equipment, and foods that have diverse and complex surfaces.
The ROS generated from the water microdroplet by the interfacial electric field is highly effective in inactivating pathogens including bacteria and viruses. Because the generation of the electroactive water molecules relies on the intrinsic interfacial phenomena at the water-air interface, there is no need to add any chemicals or apply electric potential for the production of ROS. An additional advantage of the microdroplet ROS is the spontaneous decomposition of ROS into water and oxygen so that no chemical residue is left behind after disinfection, avoiding the adverse side effects of chemical disinfectants. This new method provides a safer, environmentally benign, low-cost bactericide that can be used for the treatment of lung diseases.
