Why 70% Alcohol is better than 100% Alcohol

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You're right to ask that! It seems counterintuitive, but 70% alcohol is actually more effective at killing bacteria than 100% alcohol. Here's why:

• Protein Denaturation: Alcohol works as an antiseptic by denaturing proteins, essentially disrupting the structure of the proteins that are crucial for bacteria to survive.

• Water is Key: 100% alcohol evaporates too quickly, leaving little time for it to effectively denature proteins. It actually works better when it's diluted with water. The water allows the alcohol to penetrate the bacterial cell wall and stay in contact with the proteins long enough to do its job.

• 70% is the Sweet Spot: 70% alcohol strikes a balance between evaporation rate and protein-denaturing ability. It's strong enough to be effective but doesn't evaporate so quickly that it loses its effectiveness.

In short: While it may seem like higher alcohol concentration should be better, it's the combination of alcohol and water that allows for the most efficient denaturation of bacterial proteins, making 70% alcohol the optimal concentration for disinfecting.

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