Sterilizing Vials and Skin with Ethanol instead of Isopropyl Alcohol

[athlete.03]

I’m wondering about sterilizing the skin and tops of vials with a wipe of ethanol (e.g., Everclear) instead of the old standby isopropyl.

My logic is that isopropyl alcohol is toxic and, while I know it’s only miniscule doses, I’d just as soon avoid it.

Everclear is cheap, sterile and, at 90% ethanol, seems like it would do as good of a job (or better) than isopropyl.

Any thoughts from the wise men?

 

[Ox-Sandra-Loan]

It'll work just fine. Actualy 70% alcohol (ethanol or isopropanol) is better than 90%. (better disruption of bacterial cell walls). Most microbiology labs use 70% ethanol when they are doing sterile work.

 

[athlete.03]

It'll work just fine. Actualy 70% alcohol (ethanol or isopropanol) is better than 90%. (better disruption of bacterial cell walls). Most microbiology labs use 70% ethanol when they are doing sterile work.

I really appreciate that info.

I'd love to know ho the hell that works.

I would have assumed that since a bacterium's cell wall is composed of polysaccherides and peptides the more concentration of alcohol the merrier.

Counterintuitive and fascinating!

 

[Ox-Sandra-Loan]

I guess I should have stated better penetration of the bacterial cell walls, rather than 'disruption'
70% alcohol is a more effective antiseptic than 100% alcohol, because alcohol causes protein to denature on contact. A 90 or 95% solution coming into contact with a microorganism creates a hardened protein wall around the outside of the organism, rather than permeating into its interior. Because microorganisms can be very resilient, this protein shell can cause dormancy rather than death. This leaves the possibility of revival and a continuation the cycle of reproduction under the right circumstances. At a purity of 70%, however, the alcohol causes the denaturation to occur more gradually, and allows the alcohol to penetrate into the cell, where it can denature the intracellular proteins, killing the bacterial cell.