this post was submitted on 16 Aug 2024
405 points (97.4% liked)
Science Memes
10923 readers
2409 users here now
Welcome to c/science_memes @ Mander.xyz!
A place for majestic STEMLORD peacocking, as well as memes about the realities of working in a lab.
Rules
- Don't throw mud. Behave like an intellectual and remember the human.
- Keep it rooted (on topic).
- No spam.
- Infographics welcome, get schooled.
This is a science community. We use the Dawkins definition of meme.
Research Committee
Other Mander Communities
Science and Research
Biology and Life Sciences
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- !reptiles and [email protected]
Physical Sciences
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
- [email protected]
Humanities and Social Sciences
Practical and Applied Sciences
- !exercise-and [email protected]
- [email protected]
- !self [email protected]
- [email protected]
- [email protected]
- [email protected]
Memes
Miscellaneous
founded 2 years ago
MODERATORS
you are viewing a single comment's thread
view the rest of the comments
view the rest of the comments
Depends on what the concentration is, IIRC. 70% is better than 90%.
That seems counterintuitive, why?
ELI5 answer is 90% alcohol dries out the bacteria too fast and it converts into a bacterial spore with a hard shell that protects its insides.
70% alcohol gives it time to penetrate the cell wall and "dissolve" the insides of the bacteria, either killing it or rendering it non infective.
Iirc, the higher water content keeps the alcohol from evaporating off as fast, keeping it in contact with the surface for a longer period of time.
From what I understand, the water helps "penetrate" the cell walls of bacteria and deliver the lethal dose of alcohol. Take out more water and it's unable to penetrate and murder things as efficiently.
Alcohol and water are both polar and form hydrogen bonds, but of differing strength. You want those bonds to switch, which creates conformational changes and rips the structure of proteins apart. If you just replace all the bonds with alcohol you'll develop a new, although denatured, stable configuration which can keep the cell wall intact. Instead you want to keep developing new stresses on it until it breaks. Neither can really penetrate the phospholipid membrane of the cell because it's nonpolar, but those conformational changes create big holes where the surface proteins are.