Alcohol has been used as a disinfectant for centuries. The most common sterilizing products used today – rubbing alcohol and alcohol-based hand sanitizers – are both made from solutions of alcohol, most often isopropyl or ethyl alcohol. In Ancient Egypt, circa 3000 B.C,, palm wine was used both to clean wounds and embalm bodies. Alcohol is incredibly effective in the fight against single-celled microorganisms like bacteria, but commercials and other advertisements for household disinfectants don’t often explain the fascinating process of how alcohol kills bacteria.
Alcohol kills bacteria through a process known as denaturation. Alcohol molecules are amphiphile chemical compounds, which means that they have both water and fat-loving properties. Because bacterial cell membranes have a fat-based side as well as a water-based side, alcohol molecules are able to bond with and break down the protective membrane. When this occurs, the core components of the bacteria are exposed and dissolve, losing their structure and ceasing to function. With its organs essentially melting away, the bacteria dies quickly.
Properties of Alcohol
The rubbing alcohol and alcohol-based hand sanitizers most often used to kill bacteria are solutions of alcohol, either ethyl alcohol or isopropyl alcohol, both of which are amphiphile chemical compounds. This property allows them to bond with and break down water-based membranes and disrupt protein structures suspended in water. The molecules in the membranes and proteins easily bond with the alcohol molecules. Because single-celled microorganisms like bacteria and viruses are primarily composed of water, with fatty proteins suspended within them, alcohol’s amphiphile characteristics make it incredibly effective as a sanitizing agent. Cells exposed to it cannot survive in alcohol’s presence for more than a few minutes.