What is the primary action of alcohol-based hand sanitizers?

Alcohol-based hand sanitizers primarily function by denaturing proteins and disrupting the cell membranes of pathogens. This process effectively destroys a wide range of microbes, including bacteria and viruses, reducing their presence on the skin. The active ingredient in most alcohol-based sanitizers, usually ethanol or isopropyl alcohol, works by altering the structure of proteins, which is crucial for the pathogens' survival and function. When these proteins are denatured, the overall integrity of the microorganism is compromised, leading to its inactivation.

Additionally, the alcohol in hand sanitizers can penetrate the lipid membranes that surround many pathogens, particularly enveloped viruses, causing those membranes to break apart. This dual action—denaturing proteins and disrupting cell membranes—ensures a more comprehensive antimicrobial effect, making alcohol-based hand sanitizers effective for hand hygiene when soap and water are unavailable.

The other choices do not accurately reflect the primary action of alcohol-based hand sanitizers. For instance, creating a barrier against germs is more characteristic of physical barriers like gloves rather than a chemical action. The claim about bleaching and disinfecting surfaces pertains more to specific cleaning agents containing bleach, which is not the primary function of hand sanitizers. Finally, while some sanitizers can help in certain circumstances by