Science Memes

10322 readers

2365 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.

Research Committee

[email protected]

Other Mander Communities

Science and Research

Biology and Life Sciences

Physical Sciences

Humanities and Social Sciences

Practical and Applied Sciences

Memes

Miscellaneous

founded 2 years ago

MODERATORS

[email protected]

406

Wet Time (mander.xyz)

submitted 1 month ago by [email protected] to c/[email protected]

34 comments fedilink hide all child comments

you are viewing a single comment's thread
view the rest of the comments

[–] [email protected] 12 points 1 month ago (1 children)

Depends on what the concentration is, IIRC. 70% is better than 90%.

[–] [email protected] 7 points 1 month ago (3 children)

That seems counterintuitive, why?

[–] [email protected] 13 points 1 month ago

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.

[–] [email protected] 8 points 1 month ago (1 children)

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.

[–] [email protected] 11 points 1 month ago* (last edited 1 month ago)

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.

[–] [email protected] 4 points 1 month ago

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.