What Are Reactive Oxygen Species (ROS)?

ROS are molecules that contain oxygen and are extremely reactive. Common types include:

• Hydroxyl radicals (•OH)

• Superoxide anions (O₂⁻)

• Hydrogen peroxide (H₂O₂)

When nanobubbles collapse or release their gas, ROS are generated at very high local concentrations. These molecules attack key structures in microorganisms, damaging them beyond repair.

Which Microorganisms Are Affected?

Nanobubbles and ROS don’t just target E. coli. They can affect a wide range of microbes, including:

• Bacteria: E. coli, Salmonella, Listeria, Staphylococcus aureus

• Viruses: Influenza virus, SARS-CoV-2, norovirus

• Fungi: Candida albicans, molds, and other yeast

• Protozoa: Giardia, Cryptosporidium

How ROS Destroy Microorganisms

ROS attack microorganisms in several ways:

1. Damaging cell membranes
   ROS strip hydrogen atoms from fatty acids in microbial membranes, causing lipid peroxidation. This weakens the membrane, forms holes, and leaks vital cell contents.

2. Breaking down proteins
   ROS oxidize amino acids in proteins, making enzymes and structural proteins misfold or stop working.

3. Destroying genetic material
   Hydroxyl radicals can break DNA and RNA strands, preventing microorganisms from replicating.

4. Overwhelming natural defenses
   Microbes have antioxidants to fight ROS, but the concentrated oxidative stress from nanobubbles is too much for them to handle.

The Result: Microbial Death

With membranes breached, proteins damaged, and genetic material destroyed, microorganisms cannot survive. Nanobubbles deliver ROS directly where they’re needed, causing rapid and efficient microbial inactivation.